Saab J 29A Tunnan - 29606 Side Profile View

Saab 29 Tunnan

Cold War, Sweden, , ,

sweden flag Sweden (1950)
Fighter Plane – 662 Built

The Saab 29 Tunnan was a single-seat, single-engine transonic aircraft and first-generation jet fighter. It was a small aircraft with a single central air intake placed at the nose, a bubble cockpit and  thin sweptback wings. It was the very first Western European design to have a swept wing layout of 25 degrees rearward, incorporating many of the latest technologies of the time. Saab obtained access to WWII German studies involving swept wings and their positive effects in regards to speed in Switzerland, and as a result, the J 29 Tunnan came to be similar to the German Luftwaffe’s Messerschmitt Me P1101 project.

Nazi P.1101 vs Saab Tunnan

The Tunnan acheived a top speed of 1035 km/h which made it one of the fastest aircraft in the world in 1950. The nickname: ‘Flying Barrel’ was coined due to the shape of the fuselage, which came to resemble the shape of a barrel due to the large cross section of the engine and the size of the engine itself with a tapered nose and aft section. The Tunnan’s ungainly and small appearance could be deceiving  however it was fast enough to set several world speed records and also had a very good agility. However, the aircraft proved challenging for inexperienced pilots. The 29 was comparable to its contemporaries: the US-made F-86 Sabre and the Soviet-made Mig-15.

The development aimed initially at producing a fighter-interceptor, but reconnaissance and ground attack versions were also developed and produced, however a training version was not produced due to time constraints of the production schedule. Sweden was developing a strong air defence system that enabled it to take advantage of innovations introduced in WWII. As a result, by late 1945 the development of the Tunnan began, with the Swedish Royal University of Technology and the National Aeronautical Research Institute taking part by providing wind tunnel testing that defined the general aerodynamics of the Tunnan. Just like the Saab J32 Lansen, a single Saab Safir was modified, fitting swept wings to its airframe in order to test the design of the wings alone.

Four prototypes were built during the development process, with the first two lacking any sort of weaponry carrying heavy testing equipment instead, and the third prototype carrying four 20mm Hispano Mark V cannons. These prototypes tested different aerodynamic features, such as the location of the airbrakes – either in the fuselage or on the wings, as well as the configuration of the ailerons and flaps. The prototypes also hinted that the Tunnan design would be able to reach and even exceed the maximum Mach they were designed for. Once in service the Tunnan broke many records. It set a world speed record on a 500 km closed circuit as it reached a speed of 977 km/h in 1954. The reconnaissance version set also a record of 900.6 km/h in a closed circuit of 1000 km.

In 1948, the J 29 Tunnan flew for the first time, in service with the Flygvapnet from 1951 until 1976, with 662 fighters built from 1950 to 1956 making the Tunnan the most numerous aircraft produced Saab, as well as the longest lived design in service. It also served with the Austrian Air Force with 30 units in service until 1973. A single J 29F still can be seen flying at airshows around Europe.

Design

The Tunnan is a thin 25 degrees swept back laminar-flow mid-wing fighter, having a single tail and a single engine, featuring the design similar to most of the first generation jet fighters: a single engine with a central straight-through airflow system that maximized thrust. Two tubular pitot sensors were located at the wing tips. For lateral stability during take-off and landing, automatic-locking leading edge slots were fitted in the wings and were also interconnected with the flaps. It was later on enhanced with the installation of an afterburner and of dog-tooth leading edge in the wings – which increased the Mach speed the Tunnan could attain. Trim tabs and dive brakes were also incorporated to the design, being initially placed on the wings and later re-located to the fuselage, directly forward of the main landing doors.

The Tunnan also featured a bubble shaped canopy with the cockpit located right above the engine air intake, and forward the wing’s leading edge. The canopy was opened by sliding backwards, allowing the pilot to access and exit. The design also took advantage of the already existing ejector seat developed in 1943 by Saab, complemented by an explosive jettison system to remove the canopy in case of ejection. The landing gear was of tricycle configuration, with the rear wheels retracting into the fuselage, which contributed in making the wings thin, and a single wheel gear at the nose. The vertical stabilizer had a tapered edge, being straight trailing edge with a blunt tip, with the tail section placed above and behind the engine exhaust nozzle. In turn, the horizontal stabilizer is mounted practically at the base of the tail. The Tunnan proved to be not only a very capable and agile fighter, but also proved very durable in sorties. During a UN mission in the Congo it received intensive ground fire without sustaining any noticeable damage.

The engine, along with its aerodynamic characteristics, made of the Tunnan a fast fighter. The powerplant consisted of a DeHavilland Ghost turbojet engine producing 5000 lbs of thrust. This engine was deemed suitable for the fuselage of the Tunnan, replacing the originally planned DeHavilland Goblin, and had the advantage of making maintenance easy with the engine cowling able to be removed as a single piece.

The armament of the Tunnan consisted of four 20mm Hispano Mark V cannons placed in pairs on both sides under the nose. The pylons were capable of carrying 75mm air-to-air rockets, 145mm anti-armour rockets, 150mm HE (High Explosive) rockets and/or 180mm HE anti-ship rockets. Later versions were capable of using Rb24/AIM-9 Sidewinder air-to-air missiles. Fuel air-drop tanks could be used as napalm bombs.

Swedish Resolve

Tunnan Banking Maneuver
Tunnan Banking Maneuver

The Tunnan is the product of Swedish concerns about its security during World War II, in the face of Germany’s rapid annexations of both Norway and Denmark and acknowledging the country was unable to resist such aggression. But there were also of concerns that Sweden was falling behind after the rapid development of technologies and innovations brought about during the war. Sweden’s isolation in this aspect was exacerbated by the degree of defense secrecy by both the Axis and Allied countries. As a result, an effort was made in order to strengthen defensive capabilities with the focus being placed on the development of modern aircraft to bolster air defence, exploiting the war-time innovations in power – namely the recently introduced jet propulsion technologies as well as other advances in aircraft design. The new technologies were exploited after Sweden obtained access to research after the war. The already existing Saab J 21R was utilized to make the transition between the piston and jet propelling engines and to provide a temporary solution, but it was deemed necessary to develop a much more modern aircraft in order to keep the air defences fit. The Tunnan became the solution, making the Swedish Air Force the 4th largest during the mid-century.

Peacemaker from the North

All the aircraft produced by Saab and in service with the Flygvapnet from 1948 to 1989 saw relatively little combat. The Tunnan constitutes the only exception, as it saw extensive use during conflict in Central Africa. As the crisis in the Congo unfolded in 1961, Sweden contributed five J29B Tunnans that were tasked with protecting UN’s air transport and providing fire support to cover UN ground troops when needed, constituting the F22 unit. In 1962, four additional J29Bs and two J29Cs were sent. The 11 Tunnans provided by Sweden to the UN mission comprised the only air component of the UN at the time. As the crisis evolved and the additional six Tunnan were required, air superiority was achieved along with ground attack missions that involved the utilization of the fighter’s 4 Hispano cannons and rockets. The missions mainly focused attacks on military trains and airfields at Katanga, as other aerial assets from Ethiopia – F 86 Sabres – and India – Canberra light bombers – withdrew. When the UN peacekeeping mission was over in 1963, four of the Tunnans returned to Sweden, while the remaining met an ignominious ending, destroyed at the base, as it was deemed prohibitively expensive to return them.

Variants

  • J 29 – Four prototypes built in 1948-1950, for the development process only.
  • J 29A – Fighter version. Armed with four 20mm Hispano Mark V cannons, and 12 75mm anti-armor rockets. Later series relocated the wing-mounted dive brakes into the fuselage. Remained in service until 1965. 224 delivered.
  • J/A 29B – Fighter/attacker version. It featured an increased 50% fuel capacity and wing hardpoints with provisions to carry bombs, rockets – 8 or 14 80mm or 145mm anti-armour; 8 or 14 150mm HE; 2 or 4 180mm anti-ship – and fuel drop-tanks that could be used as napalm bombs. Served until 1965. 332 delivered.
  • J 29C – Reconnaissance version for day and night operations. It carried between 5-6 cameras in a modified nose, being unarmed cameras replaced the 4 guns. It received the same wing enhancement of the J 29E. It also became the first jet-powered photographic-reconnaissance aircraft introduced by a non-aligned nation, as well as the first Swedish aircraft to be equipped with radar warning receivers. An antenna for backwards-looking radar was placed at the tail cone, being afterwards relocated  This version set a new speed record back in 1955, reaching speeds 900.6 km/h (559.6 mph) in a closed circuit of 1000 kms (621.4 miles). 76 delivered.
  • J 29D – A single unit to test the DeHavilland Ghost RM2 turbojet fitted with an afterburning thrust, later upgraded to J 29F.
  • J 29E – Fighter version, which incorporated an enhanced wing design by fitting leading edge dogtooth, aimed at increasing critical Mach number. It also increased load factor. Same armament configuration as the J 29B. Upgraded to the J 29F version. 29 delivered.
  • J 29F – Fighter version, which were modified J 29B and J 29E airframes. This version featured the enhanced wing design of the J 29E, and the DeHavilland Ghost engine equipped with an afterburner. This version was also optimized to carry two Saab Rb24 (AIM-9 Sidewinder) missiles in 1963, having the same armament payload of the J 29B. It also performed in the role of aggressors, and performed target towing. Most were retired by 1967. 308 converted aircraft.
  • SK 29 – Planned training version. It could have featured a two-seated cockpit, with seats placed side-by-side, no armament and limited fuel capacity. Cancelled.
  • J 29R – All-weather fighter version equipped with an air intercept radar. Cancelled.

Operators

  • Sweden – The Flygvapnet operated the Tunnan from 1951 to 1967, having 665 units operating, all of the J 29A, J/A 28B, J 29C, J 29E and J 29F versions. Some were kept for countermeasures trainers and target towing duties until 1976. 11 J 29Bs and J 29Cs took part in the United Nations Operation in the Congo (ONUC), being the only Tunnan, and actually the only aircraft during the Cold War of the Swedish Air Force to take part in combat operations abroad.
  • Austria – The Österreichische Luftstreitkräfte (Austrian Air Force) operated 15 restored J 29Fs by Saab in 1961, where they formed the first Jagdbomber Staffel. An additional 15 restored J 29Fs were sold to Austria, where the two guns on the port side could be replaced by three cameras, which were moveable during flight forming the second Jagdbomber Staffel in the Austrian Air Force. These remained in service until 1972.

 

J 29F Tunnan Specifications
Wingspan 11 m / 36 ft 1 in
Length 10.23 m / 33 ft 6.7 in
Height 3.75 m / 12 ft 3.6 in
Wing Area 24.15 m² / 260 ft²
Engine 1 DeHavilland Ghost 50 Turbojet (Svenska Flygmotor RM2B Turbojet)
Maximum Take-Off Weight 7,530 kg / 16,600 lb
Empty Weight 4,580 kg / 10,097 lb
Loaded Weight 13,529 kg / 35,273 lb
Maximum Speed 1,035 kmh / 643 mph (1,075 kmh / 668 mph in full afterburner)
Range 1,500 Km / 932 miles
Maximum Service Ceiling 13,700 m / 45,000 ft
Climb Rate 2,400 m/min (7,874 ft/min)
Crew 1 (pilot)
Armament
  • 4 X 20 mm Hispano Mark V located at the nose
  • 2 Saab Rb 24 (AIM-9 sidewinder) missiles
  • 75mm air-to-air rockets
  • 80mm or 145mm anti-armour rockets, 150mm HE rockets, and/or 180mm HE anti-ship rockets.
  • 4 X SKa 10 cameras, 1 X SKa 15 camera for mapping, and 1 X SKa 5.
  • 2 X fuel drop tanks that could be used as napalm bombs.

Gallery

Saab J 29A Tunnan - 29606 Side Profile View
Saab J 29A Tunnan – 29606
Saab J 29A Tunnan - 29670 Side Profile View
Saab J 29A Tunnan – 29670
Saab S 29C Tunnan - Congo Conflict of 1961 Side Profile View
Saab S 29C Tunnan – Congo Conflict of 1961
Tunnan Landing Gear
Tunnan Landing Gear
Tunnan Front View
Tunnan – Front View
Tunnan Afterburner
Tunnan Afterburner
Tunnan Banking Maneuver
Tunnan Banking Maneuver
Tunnan Taxiing
Saab J29 Tunnan – 29670
S 29C Tunnan in UN service in 1961
S 29C Tunnan in UN service in 1961
Nazi P.1101 vs Saab Tunnan
The P.1101 of Nazi Germany compared with Saab’s Tunnan a few years later



Sources

Ängelholms Flygmuseum (n.d.). Flygplan J29 Tunnan Historia., Aviastar.org (n.d.). Aircraft Profile #36. Saab J.29., DefenceViewpoints. (2015). Five generations of US jet fighters., Dorn, W. (2013). The UN’s First “Air Force”: Peacekeepers in Combat, Congo 1960 – 1964., Goebel, G. (2016). The SAAB 29 Tunnan & SAAB 32 Lansen. Air Vectors., Guttmann, J (1998). Defining the Jet. HistoryNet., Henriksson, L. (2010). J 29 – SAAB “Flygande Tunnan” (1951-1979)., Johnson, D. (2010). Messerschmitt Me P.1101. Luft46.com., Liander, P. (2002). För 50 år sedan… J 29 Tunnan gör entré. FlygvapenNytt, (2), 34-35, Saab. (2014). J-29 Tunnan in UN Service., Saab. (2015). J-29 Tunnan Fighter, Attack and Surveillance Aircraft., Saab. (n.d.). 1940’s., Wagner, P. J. (2009). Air Force Tac Recce Aircraft. Pittsburgh, Pennsylvania: RoseDog Books., Werner, B. (2011). J29 Tunnan, Saab., Saab 29 Tunnan. (2016, July 16). In Wikipedia, The Free Encyclopedia. Images: Tunnan-29670-1997 by Rob Schleiffert / CC BY-SA 2.0, Tunnan Underside + Tunnan Gear by Alan Wilson / CC BY-SA 2.0, Tunnan Taxiing by Anemone Nemorosa / CC BY 2.0, Tunnan Afterburner by SteveH1972 / CC BY-ND 2.0

 

Saab Lansen J32D - 32606 Side Profile View

Saab 32 Lansen

Cold War, Sweden, , ,

sweden flag Sweden (1952)
Fighter Plane – 452 Built

A tandem two-seat, single-engine transonic aircraft. Intended initially as an attack aircraft, it was later developed into fighter, reconnaissance, and ECM versions thanks to the aircraft’s size, which allowed the development of the aforementioned variants. The aircraft also had low swept back wings and similar elevators located on the tail. Developed in order to replace the WWII-era light bombers, attack and reconnaissance Saab B 18/S 18, the Saab J 21R/A 21R, and provide a ground-attack complement to the Saab J 29 Tunnan. It was also developed after Flygvapnet requested an aircraft capable of attacking anywhere along Swedish long coastline within one hour after taking off from a central location, and to be capable of operating in any weather conditions, and in both day and night.

Development of the Lansen

Saab J32D Lansen - 32606

Lansen development began by 1946 with the project P1150, where a configuration of two engines was at first considered but latter scrapped given many accidents with foreign aircraft having such display. A Saab 91 Safir, a piston/propeller engine training light aircraft was modified by incorporating the swept back wings intended for the Lansen, in order to test the design. Its first flight took place in 1952, being a very advanced concept in both design and configuration, as it was an aircraft with the best design and quality in comparison to any other European design of the times. In fact, it is among the first designs in incorporating a radar. Another interesting fact is that the Lansen was the first aircraft to be designed upon a mathematical coordinate system, instead of blue prints. It also broke the sound barrier in 1953, as it exceeded Mach 1 while performing a shallow dive. In 1956 it entered in service with the Flygvapnet. 452 aircraft were built between 1954 and 1960, remaining in service until 1997, although three Lansen with experimental, research and test and trial tasks were still operating as of 2012.

Design

Saab Lansen and Hawker Hunter in Formation
Saab Lansen and Hawker Hunter

The Lansen is designed as a swept back low-wing fighter, with a single tail and a single engine, a Volvo Svenska Flygmotor RM6A, enabling a maximum speed of 1123 km/h. The Lansen was among the first aircraft to be built specifically for attack missions. Its airframe was a sleek, streamlined and clean design, in which every line was calculated using a mathematical early computer-based design. It could sustain +12g and -8g. Its low wings had a 35° sweep and a composition of up to a 10° laminar profile, having hydraulically-boosted ailerons. One-section stall fences were installed on the wings, a pitot tube on the right wing and three hardpoints. The landing gear was of tricycle configuration.

The engine was originally intended to be the Swedish STAL Dovern RM4, but as it was not ready by the time the prototypes were completed. The Svenska Flygmotor RM6A, a Swedish version of the Rolls-Royce Avon, was the used in the Lansen. The afterburner was of Swedish design. The air intakes for the engine were located at both sides of the fuselage, forward of the wing root and cockpit.

Radar

The Lansen is among those first designs implementing onboard radar. The radar array was a PS-431/A based on the French design that worked in coordination with the anti-ship Rb04C missile, one of the first “fire and forget” missiles. As not all the squadrons were equipped with radar, and usually only one aircraft of the group would carry a navigator, the Lansen  equipped with both radar and a navigator would be the leader of the group guiding the other aircraft to the target. The radar would work in tandem with a Saab S6 computerized fire-control system, a Hughes AN/AAR-4 infrared search & trach (IRST) sensor, with the radar gunsight indicating to the pilot when there would be an optimal firing solution (these systems were mostly equipped in the J32B). The S32C was equipped with a radar warning receiver, and the J 32E was equipped with jamming devices instead of the radar in the nose. All aircraft were equipped with Saab ejection seats for the crew.

Weaponry

An RB-04 Anti Ship Missile equipped on an A32A
An RB-04 Anti Ship Missile equipped on an A32A

The Lansen would carry a varied array of weaponry depending on mission and version. The basic weapons were 4 X 20 mm Bofors (or Aden M/55 30 mm) guns located at the nose, 2 Saab 304/Rb 04 anti-ship missiles or 12 or 24 unguided rockets (60, 63, 75, 135, 145 and 180 mm), and up to 12 iron-bombs (15, 50, 80, 120, 250, 500, 600 kg). it could also carry 4 Rb 24 AIM Sidewinder missiles, ECM pods, target towing pods, jamming equipment, cameras, and chaff dispensers.

A Versatile Advanced Aircraft and Potential Nuclear Warrior

Saab J32E - 32512
Saab Lansen J32E – 32512

The Lansen was a large airframe providing a versatile platform to carry a variety of different arms depending up on mission.  Along with the Saab AJ 37 Viggen, the Lansen was a contender to carry nuclear weapons as a deterrent to protect the region, but ended up never being utilized in this role. It would have been interesting to see how a nuclear-armed version of the Lansen might have worked. But even if the Lansen in the end was not a nuclear warrior, it could boast of having a very advanced capability thanks to its design process, which was the first to be designed using a computer. Furthermore, it is among the first post-war designs to have incorporated its own radar, in addition to being among the first operational swept back wing designs.

Variants

  • A 32A – The ground attack and maritime strike version of the Lansen, and the basic one. Armed with four Bofors 20mm guns on the nose, with a special device to deflect the empty casing from entering the air intakes. The fuel tank nose was also protected with a neoprene cover to protect from the casings impact. The aircraft could also carry one of the first “fire and forget” missiles, the anti-ship Rb04/Saab 304 missile. It could also carry bombs and rockets of varied calibres and payload. This version was intended to carry the nuclear weapons developed by Sweden, should it nuclear programme was not cancelled by the 60’s. Remained in service until 1978. 287 delivered.
  • J 32B – All-weather fighter version, mainly used in adverse climate conditions and at night. Armed with four 30mm Aden cannons with the casing being retained, sparing the protective measure implemented on the J 32A. 4 Air to air Rb24/ AIM 9 Sidewinder missiles and 75 m/57 mm rockets were also part of this version’s armament, all being fired by radar sighting. There was a radar display for the pilot and not exclusively for the navigator, allowing targeting without visual thanks to the fitted IR sensor (AN/AAR-4) on the wing. Remained in service until 1973. 118 delivered.
  • S 32C – Maritime surveillance and photo reconnaissance version. Fitted with a PS-432/A radar with longer instrumented range, and four cameras (SKa 17 and SKa 18), latter, SKa 23, SKa 15 and Jugner FL S2 cameras were fitted. All the cameras were for low, high and night takes. Twelve additional British 75 kg photo flash bombs were also used, mainly on the wings. Chaff dispensers and RWR gear – to give visual and aerial warning – were installed. In service until 1978. 44-45 delivered.
  • J 32D – Target towing version modified from six J 32B airframes. Remained in service until 1997. 6 delivered.
  • J 32E – ECM version from modified 15 J 32B. Also tasked with ECM warfare and ECM training. The radar was replaced by a G24 radar-jamming device against ship and land-based radars, and two chaff dispenser were incorporated. It also carried 120kg dummy bombs.  Remained in service until 1997. 15 delivered.
  • J 32AD – A proposed daytime fighter version purposed to replace the J29 Tunnan. It would have been a single seat fighter with four 20 mm guns and a fifth 30 mm gun, all located on the nose. It would have been armed also with rockets and missile but lacking a radar. Never developed and instead 120 Hawker Hunters entered in service, filling the gap between the J 29 Tunnan and the J 35 Draken.
  • J 32U – Another proposed fighter version with enhanced performance than the J 32B, with a Rolls-Royce RA 19R engine, a supplementary rocket engine, a thinner wing with 40° of sweepback, and a flying tail. Political decisions and considerations of replacing the Lansen with other types of aircraft after 8 years of service prevented this development to see the light.

Operators

  • Sweden – The Flygvapnet was the only operator of the Lansen, having this aircraft in service from 1956 to 1997. 118 airframes where of the J 32A version; 118 airframes where of the J 32B version – 6 were modified to the J 32D and other 15 were modified to the J 32E versions – and 44-45 airframes where of the S 32C version. 452 J 32 Lansen served in total with the Flygvapnet until 1997. Three Lansen remained in service by 2012 with experimental and research purposes.

 

Lansen Specifications
Wingspan 13 m / 42 ft 7 in
Length 14.94 m / 49 ft 0 in
Height 4.65 m / 15 ft 3 in
Wing Area 37 m² / 529,8 ft²
Engine 1 Svenska Flygmotor (Rolls-Royce Avon) turbofan RM6A
Maximum Take-Off Weight 13,600 Kg / 29,982 lb
Empty Weight 7,438 kg / 16,397 lb
Loaded Weight 13,529 kg / 35,273 lb
Maximum Speed 1,125 km/h / 699 mph
Range 3,200 Km / 1,988 miles
Maximum Service Ceiling 16,000 m /52,493 ft
Climb Rate 60 m/s (11,811 ft/min)
Crew 2 (pilot & navigator)
Armament
  • 4 X 20 mm Bofors or Aden0 M/55 30 mm guns located at the nose.
  • 2 Saab 304/Rb 04 anti-ship missiles.
  • 12 or 24 unguided rockets (60, 63, 75, 135, 145 and 180 mm).
  • Up to 12 iron-bombs (15, 50, 80, 120, 250, 500, 600 kg). It could have also carried nuclear bombs, in case Sweden would have continued its nuclear programme.
  • 4 Rb 24 AIM Sidewinder missiles.
  • ECM pods, target towing pods, jamming equipment, cameras, and chaff dispensers

Gallery

Saab J32E Lansen - 32620 - Side Profile View
Saab J32E Lansen – 32620
Saab J32E Lansen - 32512 - Side Profile View
Saab J32E Lansen – 32512
Saab J32E Lansen - 32507 Side Profile View
Saab J32E Lansen – 32507
Saab Lansen J32D - 32606 Side Profile View
Saab Lansen J32D – 32606
Saab J32 Banking Maneuver
Lansen Banking Maneuver
An RB-04 Anti Ship Missile equipped on an A32A
An RB-04 Anti Ship Missile equipped on an A32A
Saab J32D Lansen - 32606
One of many still airworthy Lansens enjoying retirement at an airshow.
Saab J32E Lansen equipped for ECM
Saab J32E Lansen
Saab Lansen and Hawker Hunter in Formation
Saab Lansen and Hawker Hunter
Saab J32E - 32512
Saab Lansen J32E – 32512


Sources

Aguilera, R. D. (2015). Saab 32 Lansen, Bergmans, W. (2011). J32 Lansen, Saab, Fortier, R (1997). Photo Essay Collection. Shield and Sword: Fighter Aircraft Development in the 1950s. Ottawa, Canada: National Aviation Museum., Globalsecurity.org (2012). Swedish Nuclear Weapons., Goebel, G (n.d.) The Saab 29 Tunnan & Saab 32 Lansen., Jackson, R. (2010). 101 Great Fighters. New York, NY: Rosen Publishing., Saab (2015). Saab 32 Lansen., Saab (n.d.) 1950’s.,  Sharpe, M (2001). Jets de Ataque y Defensa [Attack and Interceptor Jets, Macarena Rojo, trans.]. Madrid, Spain: Editorial LIBSA, WarbirdsUpdate (2013). The Swedish Air Force Historic Flight from Within the Cockpit. Warbirds News., Saab 32 Lansen. (2016, June 12). In Wikipedia, The Free Encyclopedia., X-Plane.org (2008). Dispersed Basing. X-Plane.org. Images: Saab Lansen 32606 by MrTMan / CC BY-SA 2.0, Saab Lansen 32512, Lansen & Hunter by Alan Wilson / CC BY-SA 2.0, Saab J32E Lansen by Leonid Kruzhkov / CC BY-ND 2.0,  RB-04 Anti-Ship Missile by AdurianJ / CC BY 2.0, Plane Profile Views by Ed Jackson

 

The Red Baron's Fokker Dr.1 475/17 - March 1917

Fokker Dr.I

German Empire, WW1

German Empire Flag German Empire (1917)
Fighter Plane – 320 Built

The Fokker Dr.I was a triplane built by Fokker-Flugzeugwerke during the First World War. The design, based off of Britain’s Sopwith Triplane, is well known thanks to the Red Baron, Manfred von Richthofen, for being the plane in which he scored his final kills.

A Borrowed Idea

In the early part of 1917 the Sopwith Triplane of the Allies began appearing on the battlefield, quickly trouncing German Albatros D.III fighters with its superior maneuverability and climbing ability. The Idfleig, the German bureau overseeing aircraft design immediately ordered development of a triplane, known as dreidecker (3 winged) in German.

Nearly all of the German aircraft manufacturers followed suit. Fokker set about to develop its own triplane by modifying an unfinished prototype biplane. This initial prototype, like Sopwith’s design, utilized a rotary engine and steel tube fuselage. However the initial prototype, the V.4 did not have external interwing bracing. The next prototype, the V.5 introduced bracing between the wings to minimize flexing on the upper wing. The prototypes were met with much excitement for their exceptional maneuverability and climb rate over anything else the Germans had previously produced. The Red Baron himself, Manfred von Richthofen was believed the Dr.I held much promise for the fortunes of German air power and demanded his superiors to commence production immediately, as well as promising his men that they would soon be able to “move like devils and climb like monkeys.”

Construction

Replica Dr.1 in a Black and White Striped Livery
Replica Dr.1 in a Black and White Striped Livery

The appearance of the Dr.1 is characterized by its three-wing design – therefore dubbed a ‘triplane.’ The design also featured small sustentation surface of an aerofoil shape mounted between the wheels of the landing gear. The tail was also completely mobile with unbalanced ailerons possessing more surface area than the ailerons of the upper wing. The wings had deep section hollow box-spars that provided lightweight strength to the wings. The lack of interplane struts on the initial prototype resulted in excessive wing vibration during flight, so interplane struts were added. The ribs were of plywood, as well as the leading-edges covers at the spar, with the leading-edges made of wire. The middle wings had some cut-outs to improve downward visibility of the pilot. The fuselage was constructed using welded steel-tubing bracing with diagonal wires to create the rigid box-shaped structure, being a fabric-covered with triangular plywood fillets, except the undercarriage and center-section, which were made of steel streamlined tubing.

The tail-plane had a triangular shape, being framed in steel tubing the same way as the balanced rudder and elevators. The wheels featured an elastic shock cord, while a steel-tipped tailskid was installed at the rear.

Evaluation

The first prototype Dr.1 flew in July of 1917. Production of the Dr.I commenced on August 11th of 1917. In preproduction the triplane carried the designation F.I. Two were made and issued to Richthofen and Leutenant Werner Voss. These two aces promptly used these planes on the battlefield, scoring kills within the first few days of flying in early September. Voss took to the skies on August 28th and by September 11th had scored 8 kills.

The result of this evaluation period led Voss and Richthofen to recommend the Dr.I for production as soon as possible, declaring it superior to the Sopwith Triplane. Orders were placed for 300 Dr.I’s.

On September 14th the commander of Jasta 11, OberLeutnant Kurt Wolff was shot down whilst flying Richthofen’s F.I by a new Sopwith Camel of Britain’s Naval 10 squadron. Voss, whilst flying on September 23rd, scored his 48th victory just before being shot down in an epic dogfight wherein he managed to damage all 7 of his opponent’s SE-5a’s in the skirmish.

The Fokker Dr.I in Use

Replica Dr.1 in Flight
Replica Dr.1 in Flight

The Dr.I, upon its arrival to the battlefield in October was well regarded for its climbing ability and light controls. The ailerons were not very effective, however the tailplane elevator and rudder controls were very yielding. Rapid turns to the right were very quick thanks to the directional instability afforded by the rotation of the rotary engine, a characteristic that was taken advantage of by pilots.

Although not a particularly fast plane, it balanced this shortcoming with great maneuverability thanks to its light weight, while also having good upward visibility. It also had a decent climb rate, characteristics that all seemingly made the Dr.I a formidable adversary to its Allied opponent, the Sopwith Camel. This made of the Dr.1 a good aircraft for dogfights, yet structural and construction problems in the wings would hamper the aircraft’s promising initial assessment.

The Dr.I was armed with twin 7.92 Spandau machine guns, which could fire simultaneously or independently in synchronization with the propeller.

The Dr.I, for all its improvements over previous German aircraft, had numerous  shortcomings. Among them was its tendency to ground looping upon landing. This occurs when the aircraft tilts on landing such that one wing makes contact with the ground. For this reason skids were attached to the wingtips of the lower wing on the production version. Also while the Dr.I had excellent climbing ability, its dive and level flight speed were less than desirable, leaving it vulnerable to faster Allied planes in many situations.

Wing Problems

Following the proper introduction of the production model Dr.I in October, by the end of the month two consecutive top wing failure accidents promptly caused all triplanes to be grounded. The wing structure of the Dr.I was thoroughly investigated and numerous problems were discovered, the first of which was weak attachment of wingtips, ailerons, and ribs. Further, the doping of the fabric and wood varnishing was found to be of poor and inconsistent quality, leading to water absorption and premature rot in crucial wing spars.

Fokker’s corrective action was to improve quality control on the production line, as well as modifying and repairing existing models. The problem was believed to have been solved, and the Dr.I continued to see use well into 1918, but later the wing failures returned.

Much later in 1929, research at NACA revealed that a triplane configuration like the Dr.I’s exerted as much as 2.5 times more lift coefficient on the upper wing. The extreme difference in this force no doubt contributed to many of the wing failures seen in the Dr.I over its operational lifespan. Examples such as this show the importance of research and competence in advanced aerodynamics during the design phase of an aircraft.

Legacy

As had been seen in September 1917, the Dr.I was inferior to the capabilities of the British Sopwith Camel by the time production had commenced. Despite this, German production went on for the initial 300 ordered.

Fokker D.VII would eventually replace the Dr.1 on the battlefield, with surviving dreideckers relegated to training and home defence units, re-powered with a Goebel Goe II 100 hp engine. By the time of the armistice was signed, the Dr.1 was tested by Allied pilots at fighter flying schools in Nivelles (Belgium) and Valenciennes (France), being deemed as an aircraft with impressive performance.

Variants

  • V.4 – The initial prototype
  • V.5 – First production prototype
  • V.6 – Enlarged prototype powered with a Mercedes D.II engine
  • V.7 – Prototype with Siemens-Halske Sh.III engine

Dr.1 Specifications
Top Wingspan 7.12 m / 23 ft 4 in
Mid Wingspan 6.23 m / 20 ft 5 in
Lower Wingspan 5.7 m / 18 ft 8 in
Length 5.77 m / 18 ft 11 in
Height 2.95 m / 9 ft 8 in
Wing Area 18.66 m² / 200.85 ft²
Engine 1  9-cylinder rotary Oberursel UR II engine (110 HP), or a LeRhône Type 9Ja (110 HP)
Maximum Take-Off Weight 586 Kg / 1,291 lb
Empty Weight 406 kg / 895 lb
Loaded Weight 586 kg / 1,291 lb
Climb Rate 5.7 m/s (1,122 ft/min) or 1000 meters in 2’45’’
Maximum Speed 185 km/h / 115 mph at sea level; 165 km/h / 102,5 mph at 4000 m
Range 300 Km / 186 miles
Maximum Service Ceiling 6100 m /20,000 ft
Crew 1 (pilot)
Armament 2 X 7.92 mm Spandau 08/15 with 500 rounds each

Gallery

The Red Baron's Fokker Dr.1 475/17 - March 1917
The Red Baron’s Fokker Dr.1 475/17 – March 1917
Fokker Dr.1 217/17 - March 1917
Fokker Dr.1 217/17 – March 1917
Fokker Dr.1 152/17 - March 1917
Fokker Dr.1 152/17 – March 1917
Replica Dr.1 in a Black and White Striped Livery
Replica Dr.1 in a Black and White Striped Livery
Replica Dr.1 Ready for Takeoff
Replica Dr.1 Ready for Takeoff
Closeup of Replica Dr.1's Cockpit
Closeup of Replica Dr.1’s Cockpit
Fokker Dr.1 9 Cylinder Rotary Engine
Fokker Dr.1 9 Cylinder Rotary Engine
Replica Dr.1 in Flight
Replica Dr.1 in Flight

Sources

Guttman, R. (2011). The Triplane Fighter Craze of 1917. HistoryNet., Berger, R (Ed.). Aviones [Flugzeuge, Vicenç Prat, trans.]. Colonia, Alemania: Naumann & Göbel Verlagsgessellschaft mbH., Donald. D. (2009). Aviones Militares, Guia Visual [Military Aircraft. Visual Guide, Seconsat, trans.]. Madrid, Spain: Editorial Libsa., Dwyer, L. (2013). Fokker Dr.I Triplane. The Aviation History Online Museum., Leivchentritt, L. (2013). Fokker Dr.I Specifications. Fokker Dr.I.com., Old Rhinebeck Aerodrome (2016). Fokker Dr.1 Triplane. Cole Palen’s Old Rhinebeck Aerodrome., The Aerodrome (2016). Fokker Dr.I. The Aerodrome., Fokker Dr.I. (2016, June 19). In Wikipedia, The Free Encyclopedia. [Images] Dr1 Black-White Livery by Neal Wellons / CC BY-NC-ND 2.0, Dr1 Dark Red by Geoff Collins / CC BY-NC-ND 2.0, Dr1 Cockpit by Phil Norton / CC BY-NC-ND 2.0, Dr1 Flight by Ian / CC BY 2.0, Dr1 Engine by Erik Wessel-Berg / CC BY-NC-ND 2.0, Plane Profile Views by Ed Jackson

Saab J35J Draken - 35556 - Side Profile View

Saab 35 Draken

Cold War, Sweden, , , ,

sweden flag Sweden (1960)
Fighter Plane – 651 Built

A single-seat, single-engine interceptor/fighter for all-weather conditions, with low double delta wings, the Saab 35 Draken was developed in order to replace the Saab J29 Tunnan and the Saab J32 Lansen. Its first flight took place in 1955, being amongst the most advanced and remarkable fighters of its time. In 1960 it entered in service with the Flygvapnet.

Development of the Draken

Draken development started in 1949, following a requirement by the Flygvapnet for a single-seat cost-efficient interceptor with supersonic capabilities and high climbing rates, able to operate in short airstrips – or even highways, roads and unprepared runways – and easy to operate with high adaptability. As a result of both the requirements and development process, the result was a double-delta winged fighter that became the first European supersonic fighter, and also a high performance air-defence asset for Sweden. And on a similar fashion as the JAS 39 Gripen and JAS 37 Viggen, it was required the Draken to be serviced, refuelled and armed up to ten minutes by untrained ground personnel. A brake parachute was incorporated to reduce landing distance. Interestingly, a prototype was built expressly to test the double-delta wing concept: such was the Saab 210 ‘LilDraken’.

J35J in Flight - Swedish Air Force
J35J in Flight – Swedish Air Force

The Draken is also a product of the needs from a neutral nation willing to keep its neutrality, and geographically placed between the two block. This reason explains the requirements, but especially its high climbing rate capabilities, so to be able to engage high-altitude bombers and fighters – namely Soviet Union bombers and fighters. It also explains the need for STOL capacities, as the Flygvapnet was implementing a system of dispersed bases, asking for highways and roads to be used as airstrips from where the aircraft could be operating, and also to reduce damage and increase survival in case of attack.

Its very unique and remarkable double-delta wing design is also explained by the technical abovementioned requirements, which gave the aircraft very good high and low speed performances. This design made the Draken capable of executing the “Cobra” manoeuvre, and also to stand well against more recent designs, as air exercises in Austria evidenced. During development it was able to unintendedly exceed Mach 1 on its first afterburner flight. It could also sustain a force of 10G turning force. And it also had a safety feature, with the introduction of a ram turbine, placed under the nose, to provide emergency power.

Despite being conceptualized as an interceptor, it performed well in dogfights and was able to undertake ground attack, training, and reconnaissance missions as well. And it proved to be a very tough and resistant design, as it is among the few jet fighter designs to be in service for 50 years. Austria, Denmark, Finland, Sweden and US National Test Pilot School were the operators of the Draken.

The design was so unique that, in fact, the Draken was studied for the design and development of the F16XL experimental prototype.

Between 600 and 650 Draken were built, serving with the Flygvapnet until 1998, with the Finnish air force until the year 2000, the Danish air force until 1993, and the Austrian air force until 2005. The Draken also flew with the Flygvapnet ‘Acro Delta’ acrobatic team.

Design

The Draken is designed as a tailless middle double-delta wing fighter, with a single tail and a single engine (A Volvo Svenska Flygmotor RM6C, bestowing a maximum speed of 2125 km/h / 1,317 mph). Its double-delta wings allow good high and low speed performances. It also provided good fuel and armament capacity. The engine air inlets are located mid-wing at each side of the cockpit, featuring a characteristic egg shape.

Considered an easy-to-fly platform, yet not suitable for untrained pilots given the high sensibility controls, and being prone to ‘superstalls’ as a very stable platform with good low flight.

Although the avionics were in principle basic, the radar was a very sophisticated one – A PS-02/A based on the French radar Thompson-CSF Cyrano – integrated with an Ericsson version of a radar Thompson-CSF Cyrano S6 fire control system. It also incorporated VHF/UHF radio, a radio altimeter, a transponder, an IFF (Identification Friend or Foe) system, and the Swedish version of the Lear-14 autopilot. The seat of the pilot was reclined 30 degrees, similarly like the Viggen, to allow the pilot to resist G-forces. And the cockpit was fitted with air-conditioning and pressurization.

J35J Green Camouflage
J35J Green Camouflage

The engine in combination with the design, made the Draken a very manoeuvrable and fast fighter jet, with the braking parachute assisting the aircraft in the landing, reducing the distance required to reach a full stop. Earlier version of the Draken had two 30 mm Aden M/55 cannons, with later versions having only one cannon. Also some export versions kept the two cannons configuration.

An Advanced Cold Warrior

The Draken can boast not only being a radical and new design thus making it a very advanced one by the first decades of the Cold War. It was among the first fighters in incorporating an on-board radar and the earlier version of the data-link system, whose enhanced version was incorporated in the J 37 Viggen and the JAS 39 Gripen. Indeed, the Draken incorporated the STRIL 60 ground-control network that enable Draken pilots a firing guidance through the on-board instruments, being the system also capable to resist electronic jamming. Aside the fact of being the first European supersonic jet fighter, the Draken was the first fighter to have STOL capacities, and it was an aircraft that gathered valuable intelligence by producing photographic material of many new Soviet aircraft during the 70’s and 80’s. It also had a superior service ceiling in comparison with fighters of its times. Being a very resisting and long-endurance fighter, many pilots of the Draken stated that it was able to take on much newer designs.

Variants

  • J 35A – The first version of the Draken. Capable of performing fighter tasks. A small retractable wheel was placed on the rear fuselage as the angle of the nose was required to be elevated during landings to stop the airplane. But the wheel was also placed as the fuselage was enlarged, as the EBK 66 afterburner was incorporated. This version had 2 Aden 30mm cannons, installed on each engine air take, 2 to 4 Rb 24 (Swedish version of the AIM-9B Sidewinder missile) and a central fuel tank or an additional Rb 24. The afterburner installation allowed the Draken 35A to carry Bofors 135mm rockets (up to 12) in rocket pods. This version had basic avionics, being upgraded with the SB6 fire-control system, which included an infrared search and track sensor (IRST). 90 aircraft produced.
  • J 35B – Interceptor and fighter version. Its development began in 1956, before the J 65A was developed. It initially performed training task until better engines and avionics were available. This model then incorporated the air-to-ground STRIL 60 system, and new radar and fire-control systems that enhanced collision course interceptions. It had an ejection seat that allowed the pilot to eject at zero altitude. This version was armed with two 75mm Bofors cannons, folded-fin air-to-air unguided rockets, and for ground-attacks, 135mm rockets. 73 produced.
  • Sk 35C – Trainer version. Two-seat aircraft build upon J 37A airframes, being exported to Denmark and Finland. The second section was raised for the instructor’s place – being located right behind the pilot/student – and fitted with a 3D stereoscopic periscope. Upgraded with afterburners and improved avionics. The tail section was shortened, and the aircraft could be easily re-modified to its J 35A version if necessary. 25 delivered.
  • J 35D – Fighter version, equipped with a better engine – a Svenska Flygmotor RM6C – that made this version the fastest (up to Mach 2), which allowed increased payload, but also meant increasing fuel capacity. Its avionics were also upgraded, receiving a Saab FH-5 autopilot, an Ericsson PS-03 radar coupled with a Saab S7A fire-control system and a new ejection seat, replaced latter with a seat that allowed ejection on zero/zero conditions. 120 delivered.
  • S 35E – Reconnaissance version. It was unarmed but equipped with ECM measures. Fitted with seven cameras: a vertical-looking camera; a forward-looking camera on the nose; a downward/vertical looking with wide-angle camera and two sideways-looking cameras; and two long focal length vertical cameras. A downward-looking periscope and a voice recorder were fitted to allow the pilot to aim the cameras and make comments on the imagery. Latter improved with afterburners, chaff dispensers and two radar alerts, and the ability to carry on the central pylon a night-time Vinten Blue Baron multisensory night photography device. 60 delivered.
  • J 35F – Fighter version. It had improved avionics and electronics, such as integrated radars, radios, aim, infrared target seekers, and missile systems. In fact, it had the STRIL 60 incorporated. It was the version with enhanced armament, such as two semi-active radar homing Rb 27 AAM missiles, and two Rb 28 or Rb 24 AAM missiles. As a result of the new avionics, the second 30 mm cannon was supressed. Used by 18 squadrons in the Flygvapnet. 208 delivered.
  • J 35F2 – A J 35F fitted with a Hughes Aircraft Company N71 infrared sensor.
  • J 35J – Fighter version that kept the Draken in the inventories of the Flygvapnet, co-operating with the J 37 Viggen. It has six pylons, which increased the payload. It incorporated enhanced fire-control systems, infrared sensors, radar, altitude warning systems, navigation systems, IFF and modernised cockpit electronics. It also had a slightly improved RM6C engine that provided more speed. 76 delivered.
  • 35H – Proposed export version for Switzerland. None built or delivered
  • 35XD – Export versions for Denmark. It comprised the F-35 strike aircraft, TF-35 two-seat trainer and the RF-35 reconnaissance jets. Overall the 35XD were the heaviest aircraft of the Draken family, as they were optimized for strike missions. 51 delivered.
  • 35XS – Export version for Finland, some of which were locally assembled by Valmet under license in Finland. The received/assembled aircraft were the interception, fighter-bomber and training versions. 48 delivered.
  • 35BS – Used J 35B bought by Finland
  • 35FS – Used J 35F bought by Finland
  • 35CS – Used Sk 35C bought by Finland.
  • 35Ö – Version for Austria. Used J 35Ds that were refurbished and modernised by Saab, with extra 1000 flying hours, radar warning receivers, the radar of the J 35D, and chaff dispensers. Like the earlier version of the Draken, it was armed with the two 30 mm Aden cannons. 24 delivered.

Operators

  • Sweden – The Flygvapnet had 544 Draken: 90 J 35A; 73 J 35B; 25 Sk 35C; 120 J 35D; 60 S 35E; 208 J 35F; and 76 J 35J. Many were upgraded or modified airframes, so the number is an approximation. Many were sold to other countries.
  • Austria – The last exporter of the Drakens. The Österreicher Luftstreitskräfte received 24 J 35Ö – ex-Swedish J 35D – to replace the J 29F Tunnan in 1987. Initially many Draken (5 Sk 35C) remained in Sweden for training purposes, being replaced later by a simulator. The Austrian Draken were originally armed with two 30mm Aden cannons, as AIM missiles were restricted by a treaty after WWII. But as the crisis escalated in former Yugoslavia by 1993, deeming that cannons were not enough to protect the airspace, Austria acquired AIM 9P3 and AIM 9P5 Sidewinder missiles from the US and equipped them on the Draken.
  • Finland – The second exporter of Drakens, receiving 12 all-weather J 35XS interceptors, 7 ex-Swedish J 35BS, 24 ex-Swedish J 35FS and 5 ex-Swedish Sk 35CS, all to serve with the Suomen Ilmavoimat. Most of the received aircraft were delivered in kit form and assembled by Valmet in Finland, and had also two Aden 30 mm cannons. Finland used the Draken as interceptors and fighter-bombers, and retired them in 2000.
  • Denmark – The first country in exporting the Draken, with units being received in 1970. As the original version was the least favoured during the competition for a new Danish fighter, Saab created a new version (J 35XD), based on the J 35F. the structure was strengthened in order to allow more payload – 9 reinforced pylons – with simultaneous use possible. The landing gear was reinforced with an added arrestor hook, and had two Aden 30 mm cannons, as well as extra fuel capacity. Being a European cost-effective platform, plus the improvements, made the Kongelige Danske Flyvevåben to choose the Draken. 20 A 35XD ground attack fighters (denominated F35), 30 S 35XD reconnaissance (denominated RF35), and six Sk 35XD training (denominated TF35) were purchased. 7 additional aircraft were purchased to be cannibalized. Danish training and reconnaissance versions were fitted with cannons and pylons to carry weapons, thus having secondary combat capabilities. 5 further Drakens (TF35) were purchased. Receiving upgrades in the following years, the Draken were retired from Danish service in 1993.
  • US National Test Pilot School – Operated 6 Drakens, formerly Danish Air Force jets training and reconnaissance versions.

Draken Specifications
Wingspan 9.42 m / 30 ft 10 in
Length 15.20 m / 49 ft 10 in
Height 3.8 m / 12 ft 7 in
Wing Area 49.22 m² / 529.8 ft²
Engine 1 Svenska Flygmotor Turbofan RM6B
Maximum Take-Off Weight 10,089 Kg / 22,200 lb
Empty Weight 6.590 kg / 14,500 lb
Loaded Weight 16,000 kg / 35,273 lb
Maximum Speed 1,900 km/h / 1,200 mph
Range 3,250 Km / 2,020 miles
Maximum Service Ceiling 18,000 m /59,100 ft
Climb Rate 200 m/s ( 12,000 m/min / 40,000 ft/min )
Crew 1 (pilot)
Armament • 1 Aden 30mm Cannon
• 6 hardpoints that could allow 1700 kg of payload. A pod for a 135mm Bofors M70 rockets; air-to-air Rb 24, Rb 27 or Rb 28; external fuel tank; iron bombs; cameras.

 

Gallery

Saab J35J Draken - 35556 - Side Profile View
Saab J35J Draken – 35556
Saab 35Ö Draken - 351408 - Side Profile View
Saab 35Ö Draken – Austrian Air Force
Austrian Air Force Saab J35Oe Draken 351421
Saab J35Ö Draken – Austrian Air Force

Sources

Ängelholms Flygmuseum (n.d.). Flygplan J65 Draken Operational History., Boyne, W (December 2011). Airpower Classic. J35 Draken. Air Force Magazine, 94 (12), 68., Cpt. Moore, V. (2005). A Dragon’s Farewell. Warbirds, 28 (8), 12-16., Guerras del Siglo XX (1994). Guerras del Siglo XX, Aviones. Madrid, Spain: Editorial Altaya., Liander, P. (1999). Draken pensionerad. FlygvapenNytt, (1), 24-27., Martin, G. (2012). The Draken: One of Sweden’s finest fighters. Aircraft Information., Piccirillo, A. C. (2014). Elegance in Flight. Washington, DC: National Aeronautics and Space Administration., Sharpe, M (2001). Jets de Ataque y Defensa [Attack and Interceptor Jets, Macarena Rojo, trans.]. Madrid, Spain: Editorial LIBSA (Original work published in 2001)., WarbirdsUpdate (2013). The Swedish Air Force Historic Flight from Within the Cockpit. Warbirds News., Saab 35 Draken. (2016, April 2). In Wikipedia, The Free Encyclopedia., Winchester, J. (2012). Jet Fighters: Inside & Out. New York, NY: Rosen Publishing., X-Plane.org (2008). Dispersed Basing. X-Plane.org., Images: Draken in Flight by Alan Wilson / CC BY-SA 2.0, J35J Draken Exhibit by Alan Wilson / CC BY-SA 2.0

 

Spandau LMG08/15 1918 - Side Profile View

Spandau LMG 08

German Empire, WW1, , , , , , ,

German Empire Flag German Empire (1915)
Machine Gun – 23,000 built

The Spandau LMG 08 was the air cooled aircraft version of the German Army’s MG 08 machine gun. The infantry version of the MG 08, like the Vickers Machine Gun, was water cooled and based on the design of Hiram Maxim’s famed Maxim Gun.

Design

After the success of the MG 08 in infantry use, Spandau set about lightening the weapon and adding large slots to the water jacket for aircraft use.  The first letter in lMG 08 is actually a lowercase L which stands for luftgekühlt meaning air cooled. From the beginning the lMG was designed to fire in a fixed position from an aircraft.

Early Spandau LMG 08 Triple Mount
Early “Overlightened” LMG 08

Early designs had so many cooling slots that the weapon was considered “over-lightened” and the rigidity of the cooling jacket was considered “fragile.” Various slot patterns were experimented with until the final design of the LMG 08/15, a refined version of the weapon with many improvements as well as a lighter weight. The final weight for the refined lMG 08/15 came out to 26 lbs compared with 57 lbs for the original iteration of the MG 08. The various versions of the lMG were all designed to be interchangeable so aircraft could be easily upgraded to newer versions. Like the Vickers, the closed bolt design lent itself to easy synchronization with the propellers, with most German fighters appearing with twin LMGs by late 1916 with the introduction of the Albatros D.I and D.II.

The ammunition belt of the lMG 08 utilized the design of the Parabellum MG14 for its light weight, rather than that of the infantry version of the MG 08. After a cartridge was fired the belt was fed into a side chute on the side of the breech block. The chute would guide the empty belt into a storage compartment to prevent the empty belts from interfering with any aircraft mechanisms.  Empty cartridge cases however were expended out of a round hole on the receiver just under the barrel on all version of the MG 08. In most aircraft the empty cases were guided out of the aircraft.

Use of the Spandau lMG 08

The lMG 08 was used on almost all German fighter aircraft of the WWI period. After its introduction in 1915, synchronization technology was rapidly being developed. On the Fokker E.I the introduction of the synchronizer system with a single mounted lMG 08 led to a period of German air superiority over the Western Front known as the Fokker Scourge. Later aircraft almost universally used a twin synchronized setup, including Germany’s most famous ace, Baron von Richthofen ‘The Red Baron.’

Twin Synchronized lMG 08s on a replica Fokker DR.I
Twin Synchronized lMG 08s on a replica Fokker DR.I

There were various styles of cocking handles in use, seemingly dependent upon pilot preference. Safety interlocks were also introduced to ensure the safety of the ground crew who at times could be in the line of fire. Another modification seen in aircraft use was a countdown style rounds counter.

Spandau lMG 08 Gun Specifications
Weight 12 kg / 27 lb
Length 1.45 m / 4 ft 9 in
Barrel Length 720 mm / 28 in
Cartridge 7.92mm x 57
Action recoil with gas boost
Rate of Fire 400 to 500 rounds/min
Muzzle Velocity  860 m/s  /  2,821 ft/s
Effective Firing Range 2,000 m / 2,200 yd
Maximum Firing Range 3.500 m / 3,800 yd (indirect fire)
Feed System 250 round fabric belt

Gallery

Spandau LMG08/15 1918 - Side Profile View
Spandau lMG 08/15 – 1918

Sources

Fokker E.I. (2016, April 21). In Wikipedia, The Free Encyclopedia., Synchronization gear. (2016, May 15). In Wikipedia, The Free Encyclopedia., MG 08. (2016, March 22). In Wikipedia, The Free Encyclopedia., The Vintage Aviator (n.d.), The Spandau LMG 08/15, Images: Fokker DR.I Spandau Guns – 2013 by Julian Herzog / CC BY 4.0

Saab Viggen - Takeoff

Saab S37 Viggen

Cold War, Sweden, , , , ,

sweden flag Sweden (1971)
Multirole Fighter Plane – 329 Built
The Saab Viggen is a single-seat, single-engine fighter with a low double delta wing and with two canards equipped with flaps, intended to replace the Saab J35 Draken. Its first flight took place in 1967. When it entered service in 1971 with the Flygvapnet, the Swedish Air Force, it was the most advanced fighter jet in Europe until the introduction of the Panavia Tornado (1981). It was also the first canard-designed aircraft to be produced in a large quantity.

Development of the Viggen

Development for the Viggen began in 1952, with the development period of 1958 to 1961 being crucial for the airplane, as it was decided to integrate the System 37 as standard arms control. This system would end integrating radar, air-defence screens (Stril 60), and computers, and the Viggen were intended to be the platform for such system. This system made the aircraft extremely advanced in comparison to other designs. Along with the Draken it was the precursor to the advanced datalink system the Gripen would later incorporate. Like most of Swedish designs, it also had short taking-off landing (STOL) capabilities (500 meters), thanks to canards, a thrust reverser – that allowed the aircraft to reverse on the ground, and an afterburner to facilitate short take offs. The engine and the remarkable HUD capability also assisted in landing operations.

Interestingly, it can withstand a force of 12G, but operational limit is 7G. It is also a multirole aircraft. However the multirole ability resides more in a basic airframe giving way to different versions: fighter-bomber, attack, tactical reconnaissance, sea reconnaissance, training, and fighter. Given the specific defence conditions of Sweden, the aircraft was required to be easily maintained and serviced by airmen with little training, within a time of 10 minutes.

329 Viggens were built, and served in the Flygvapnet until 2005. Noteworthy to mention that the Swedish Air Force was the main and only user of the Viggen. Agreements with the United States provided technology enough to increase the performance of an already advanced fighter, making it one of the most advanced during most of its service life.

Design

Saab Viggen - BankingThe Viggen is designed as a low double delta wing fighter, with a single tail and a single engine (A Volvo Turbofan Flygmotor RM8B, the most powerful installed in a jet fighter upon its introduction, achieving a maximum speed of Mach 2. It has canards with flaps that provide lift for both flight and taking-off and landing. Assessed as a very stable platform with good low flight, the canards and the combination of the engine, the thrust reverser, the HUD, and the afterburner allows for STOL capabilities (Taking off: 400 mts/ 1310 ft; landing: 450-500 mts/1640 ft).

The wings were provided with dogtooth at the attack border, in order to improve stability at high incidence angles. The structure was built with aluminium with a honeycomb structure, with the rear being totally of aluminium, allowing the Viggen to withstand the stress of no-flare landings, while the vertical stabilizer, or tail, was made tall given the requirements the large anti-ship missiles existing back then imposed on the design. It has a “hump” on the dorsal area to reduce drag. An interesting feature of the tail is that it can be folded, so to enhance the storage in underground and/or smaller hangars. Earlier version of the Viggen did not have an internal cannon, as it was considered by the days a close-range combat was not necessary, an approach that also affected other designs, such as the American Phantom F4. Further variants incorporated an internal cannon. The pilot seat was angled by 19 degress so to allow the pilot to resist better G forces.

A Cold Warrior with Digital Features

Saab Viggen - CockpitThe Viggen was intended to be a single pilot fighter, making the introduction of advanced avionics a requirement as there would be no navigator. As a result, the Viggen incorporated the CK 37 (Centralkalkylator) computer, the first airborne computer with integrated circuits, and that even remained in service with the Flygvapnet fleet of Viggens until the early years of the 21st century. During the development of the Viggen’s electronic components, operational aspects like vibration, exposure to strong forces and even crashes were considered, resulting in a very strong computer with a strong hardware capable of resisting crashes while keeping valuable information of the aircraft. It was also a very valuable computer for the Viggen, as it was able for assisting the pilot and aircraft missions and control of the aircraft.

Another important avionics element of the Viggen, working in tandem with the integrated computers, was the radar, an Ericsson PS-37 X radar. This radar was able to perform air-to-ground and air-to-air telemetry, search, track, terrain avoidance and cartography tasks. The further versions of the Viggen received enhanced avionics and electronic/digital components, enhancing their capabilities and mission performance.

Guardian of Neutrality

The Viggen is a pure product of the times it was designed and the context in which Sweden was a neutral country forced to increase its military power in order to safeguard its neutrality during the heated days of the Cold War. As Sweden was a close neighbor to the Soviet Union, many incidents between the two nations took place. Those incidents prompted Sweden to have an alert service, with round-the-clock radar surveillance, fighters and attackers on high readiness for combat, among other measures. The design therefore was intended to meet the defence needs of Sweden and the missions of the Flygvapnet.

Saab Viggen - TakeoffA first requirement was for the Viggen to have STOL capabilities, so to be able to operate from damaged runways – or runways and highways – and also from secondary airfields. The aim of such operational conditions was to increase the survival of air assets and to difficult the destruction, blocking or dispersion of such assets by an aggressor. A second requirement was the Viggen to be serviced, refuelled and rearmed in less than ten minutes by untrained personnel. This, considering that Sweden’s particular defence conditions required small and dispersed air and field bases, having little personnel and facilities. In fact, and thanks to this system, the Viggen was able to execute up to 11 sorties within a period of 24 hours. In addition, the Viggen became the main asset of Swedish air defence, intercepting, patrolling, and monitoring Soviet and Western activities and flights. This explains the multi-role capacities of the Viggen, or at least to have served as a basis for different versions using the same airframe. It also allowed Sweden to demonstrate its readiness. During the S-137 Soviet submarine incident, the submarine ran aground on the Swedish archipelago and Soviet surface vessels closed in on the Swedish coast to attempt a rescue, armed Viggens were put into the air so to ward-off the Soviets. Also, with the routine of the American SR 71 Blackbird path known, the Viggen was able to get radar-lock on the SR71 despite the jamming measures of the reconnaissance plane and thanks to coordination with ground-based radars. It is the only aircraft that managed to lock onto the SR 71.

Variants

  • AJ 37 – An all-weather attack aircraft with air-to-air secondary capacity. Considered outdated, it lacked a gun, but had increased bombing precision thank to its HUD and Weapons Aiming Computer System. Armed with rockets and iron bombs for strike missions, and Saab 305/Rb 05 or Sidewinders and 30mm cannon pods for air-to-air. It also had anti-ship capabilities thanks to the Saab 304 anti-ship missile. 108 delivered.
  • Sk 37 – Training version, with a second cockpit and the avionics and fuel removed, also lacking a radar array. It had instead of the internal fuel tank, a permanent fuel tank under the belly. It also had a shorter range. The second cockpit has two periscopes to provide forward view. It was tasked with providing pilots conversion and supersonic training. It also had secondary combat capacities. 10 were converted to electronic warfare trainers (SK 37E). 17 delivered.
  • SF 37 – All-weather reconnaissance version and intended to substitute the S35E. The nose had a peculiar form thanks to the fact that the recce equipment was placed there, with seven cameras. On the hardpoints further reconnaissance equipment was placed. One camera can take infrared pictures, two vertical cameras can take shots for high-altitude, and four cameras for low-altitude shots. It had the same armament as of the JA 37 interceptor version yet lacking of radar. 28 delivered.
  • SH 37 – Single seat version fitted for sea surveillance and attack/anti-ship roles, armed usually with the Saab 305 anti-ship missile and other ground-attack weaponry. It could also carry Sidewinder missiles for self-defence. 28 delivered.
  • JA 37 Jaktviggen – All-weather interceptor version of the Viggen, powered with a Flygmotor RM8B. Incorporated an internal 30 mm Oerlikon cannon, and could operate AMRAAM, Sidewinder or Rb71 Sky Flash missiles. Armed also with radar and infrared homing missiles. It also had upgraded avionics, such as a long-range Ericsson UAP-1023 pulse Doppler radar, enhancing target acquisition, and new computers that enhanced as well the aircraft performance. In fact, there is a coupling of radar gunsighting with the autopilot, presenting a lock information to the pilot’s HUD while increasing the cannon lock thus reducing the workload for the pilot. It also had an inertial navigation system. Furthermore, it provides tracking for land, air and sea-borne targets while resisting to ECM attacks. Some were upgraded with airframes, avionics and software modified for international duties (JA 37C, JA37D, and JA37DI) 149 delivered.
  • Saab 37 Eurofighter – Proposed replacement for NATO F-104 Starfighter. None built.
  • Saab 37 X – Proposed version to be exported to Norway. None built.

Operators

  • Sweden – The Flygvapnet has 329 Viggens, 108 of which are AJ 37, 17 were Sk 37, 28 were SF 39, 28 were SH 37, and 149 were JA 37.

Viggen Specifications
Wingspan 10.6 m / 34 ft 9 in
Length 16.40 m / 53 ft 9 in
Height 5.6 m / 18 ft 4 in
Wing Area 46 m² / 500 ft²
Engine 1 Volvo Flygmotor Turbofan RM8
Maximum Take-Off Weight 20,500 Kg / 45,194 lb
Empty Weight 11,800 kg / 26,014 lb
Loaded Weight 16,000 kg / 35,273 lb
Maximum Speed 2,125 km/h / 1,320 mph
Range 2000 Km / 1,242 miles
Maximum Service Ceiling 18,000 m /59,100 ft
Climb Rate 203 m/s ( 12,000 m/min / 40,026 ft/min )
Crew 1 (pilot)
Armament • 1 Oerlikon KCA 30mm cannon (JA 37)
• 7 hardpoints that could allow 6000 kg of payload. A pod for Aden 30 mm cannon; 135mm Bofors M70 rockets in pods for six rockets; air-to-air Saab 305/Rb 05, Rb71 Sky Flash, AMRAAM or Sidewinder missiles; air-to-surface or Maverick missiles; Anti-ship Saab 304; 120 kg iron bombs.

Fighter Pilots and Fighter Jets

Fighter pilots play an important role in the military. Fighter pilots do more than fly the world’s most advanced fighter jets like Saab S37 Viggen. They work with tactical aircraft to destroy enemy targets. Fighter pilots have a wide range of responsibilities in their respective military Department of Defense. An excellent fighter pilot might be awarded honors, such as challenge coins, aviator badges, etc. If you are interested in plane encyclopedias, or if you are looking for interesting things related to the Air Force, pilots, and fighter jets, you can try customizing Air Force Challenge Coins on GS-JJ, which would be excellent military-related gifts and souvenirs.
challenge coin

Sources

Anrig, C. F (2005). Flygvapnet, The Swedish Airforce in an Era of Transition. Air Power Revue, (4) 36-44., Ängelholms Flygmuseum (n.d.). Flygplan J37 Viggen., Berger, R (Ed.). Aviones [Flugzeuge, Vicenç Prat, trans.]. Colonia, Alemania: Naumann & Göbel Verlagsgessellschaft mbH., Boyne, A (July 2014). Airpower Classic. JA37 Viggen. Air Force Magazine, 97 (7), 76., Lemoin, J (2002). Fighter Planes. 1960-2002., Groebel, G (2016). The SAAB 37 Viggen., Jiewetz, B (n.d.). Central Computer for aircraft Saab 37, Viggen. DATASSABs Vänner., SAAB (n.d.). Saab 37 Viggen. Brochure., Sharpe, M (2001). Jets de Ataque y Defensa [Attack and Interceptor Jets, Macarena Rojo, trans.]. Madrid, Spain: Editorial LIBSA (Original work published in 2001)., WarbirdsUpdate (2013). The Swedish Air Force Historic Flight from Within the Cockpit. Warbirds News., Saab 37 Viggen. (2016, May 1). In Wikipedia, The Free Encyclopedia., Gunston, Bill and Mike Spick. Modern Air Combat: The Aircraft, Tactics and Weapons Employed in Aerial Warfare Today. New York: Crescent Books, 1983. Images: Saab Viggen Banking by Alan Wilson / CC BY-SA 2.0, Saab Viggen Intake by Houser Wolf / CC BY-ND 2.0, Saab Viggen Gear by Alan Wilson / CC BY-SA, Saab Viggen Takeoff by Alan Wilson / CC BY-SA, Saab Viggen Cockpit by Per80 / CC BY-SA 3.0, Saab Viggen Engine Inspection by Rune Rydh / Flygvapenmuseum / CC BY 4.0

Gallery

Vickers-Gun - Aircraft Version 1

Vickers Machine Gun

Great Britain, WW1, , , , ,

british flag Great Britain  (1912)
Machine Gun
The Vickers Gun or Vickers Machine Gun as it is often called was one of the first armaments fitted to an airplane for combat in the early 1910s. The weapon, originally water cooled and based on the successful Maxim gun, was designed and manufactured by Vickers Limited of Britain and fitted to many early British and French fighter planes.

Origins

The origins of the Vickers gun can be traced back to Hiram S. Maxim’s original ‘Maxim Gun’ that came to prominence in the 1880s as a deadly armament of the British Empire. This machine gun was extremely efficient due to its novel recoil based feed operation, which utilized the recoil of the weapon to eject the spent cartridge and insert another one. The weapon was also water-cooled for maximum efficiency and due to this could be fired for long durations.

The Vickers Machine Gun Design

Vickers-Gun - Aircraft Version 1
The Vickers Aircraft Machine Gun – Fires British .303 (7.7 mm) rounds

Vickers improved on this design by lightening the overall weight of the weapon as well as simplifying and strengthening the parts of the internal mechanisms. Another significant improvement was the addition of a muzzle booster, which restricts the escaping high pressure gases from the barrel, forcing more energy to the backwards motion of the barrel without increasing recoil force.

The Vickers attained a solid reputation upon its introduction in 1912. Despite its bulk and weight of around 30 lbs (15 kg), not including water and ammunition, it was praised by crews for its dependability. Thanks to its water cooling it could be fired practically continuously, requiring only a barrel change for roughly every hour of operation.

Use in Aircraft

Vickers Gun - mounted on a Bristol ScoutThe first use of the Vickers Gun on an aircraft was on Vickers’ own experimental E.F.B.1 biplane prototype, the first British aircraft ever to be designed for military purposes. The gun recieved a few modifications for aircraft use. The water cooling system was deemed unnecessary due to the more than adequate flow of cool, fast-moving air over the barrel in flight. However the water jacket assembly had to be retained due to the barrel action mechanism, but several rows of aircooling slots were added.

Vickers Gun - RAF RE8An enclosure was added to cover the belt feed to prevent wind from kinking the incoming ammunition belt. The belt links were a disintegrating type which meant each belt link was ejected along with each spent cartridge as the weapon fired.

The closed bolt design of the Vickers Gun lent itself to forward firing use in aircraft due to its ease of integration with a synchronizer system. In a closed bolt type of firing mechanism there is virtually no delay between the trigger being pulled and the firing of the weapon, unlike the open bolt design utilized by the Lewis Gun. The introduction of the synchronizer gear system allowed for forward firing through a propeller’s field of rotation.

Colt was licensed to manufacture Vickers Machine Guns in the U.S. and had a large order for the guns from Russia in 1916. After the Russian revolution kicked off in early 1917, the Russian orders were cancelled. The thousands of guns that had been produced sat in storage until a need arose in Europe for a machine gun that could fire larger caliber incendiary rounds to destroy German hydrogen filled balloons. It was decided to use the 11 mm French gras round. All of the previously Russian sized 7.62s were altered to accept the 11mm round. Additionally they were modified for aircraft use, with the appropriate cooling slats cut into the water jacket assembly. These 11mm Vickers became known as “Balloon Busters.”

Vickers Gun - Colt Balloon Buster
The Vickers Machine Gun – 11mm “Balloon Buster” made under license in the U.S. by Colt

Legacy

The aircraft version of the Vickers Gun was by far the most used weapon on British and French fighter aircraft of World War I and the interwar period with some still in use towards the end of World War II. Most of the fighter planes developed in early WWI utilized a single .303 British (7.7mm) Vickers Gun such as the Sopwith Triplane. Later fighters like the Sopwith Camel were able to double their firepower with twin synchronized guns. Advances in aircraft design that took place through the 1930s saw the fixed armaments on aircraft shift towards the wings, allowing for larger, more powerful, and faster firing Browning 1919 machine guns to be fitted, thus signaling the end of the Vickers machine gun’s use in aircraft. The conventional infantry version of the weapon would continue to see service with British ground forces until 1968.

Vickers Machine Gun Specifications
Weight  15 kg / 33 lb
Length  1.12 m / 3 ft 8 in
Barrel Length  720 mm / 28 in
Cartridge  .303 British / 7.7 mm
Action  recoil with gas boost
Rate of Fire  450 to 500 rounds/min
Muzzle Velocity  744 m/s  /  2440 ft/s
Effective Firing Range  2,000 m / 2,187 yd
Maximum Firing Range  4,100 m / 4,500 yd (indirect fire)
Feed System  250 round canvas belt

Gallery

Sources

Vickers machine gun. (2016, April 20). In Wikipedia, The Free Encyclopedia., Segel R. (n.d.). THE U.S. COLT VICKERS MODEL OF 1915  WATER-COOLED MACHINE GUN, Small Arms Review.,  MG34. (2012, September 3). My 1918 US Colt/Australian/Turkish Vickers Mk.1 Medium Machine Gun. War Relics Forum.

 

Albatros D.III

German Empire, WW1, , , , ,

German Empire Flag German Empire (1916)
Fighter Plane – 1,866 Built
The Albatros D.III was a bi-plane fighter manufactured by Albatros Flugzeugwerke Company in the Aldershof district of Berlin, Germany. The plane helped secure German air superiority and several top German aces flew the D.III, including Manfred von Richthofen – The Red Baron.  It was armed with 2 7.92mm LMG 08/16 machine guns which were an air cooled and synchronized version of Germany’s MG08.

Design of the D.III

Designed by Robert Thelen, the D.III was based off of the D.I and D.II that preceded it, utilizing the same basic fuselage.   This fuselage design was semi-monocoque, meaning that the skin of the aircraft, which was plywood, could bear some weight and add structural rigidity.

Albatros D.III - The Red BaronAfter seeing the success of the French Nieuport 11 and 17, the Idflieg which was the bureau overseeing German aviation development at the time requested that the new D.III adopt a sesquiplane layout similar to the Nieuports. A sesquiplane configuration consists of a modified biplane design with shorter and and narrower lower wings with the advantage being less drag at speed. As a result, the top wing was lengthened, and the lower wing’s chord was shortened, meaning the wing measured less from leading edge to trailing edge. The bracing, between the top and bottom wings was reconfigured to a “V” shape leading owing to the single spar used in the lower wings. Because of this the British coined their own nickname for the D.III: “The V-strutter.”

Water Cooled Mercedes Power

The D.III utilized a water-cooled Mercedes inline 6 cylinder 4 stroke engine appropriately designated as the D.IIIa. The water cooling and overhead camshaft yielded more horsepower than the radial engines that were more common, with the D.IIIa pumping out 170 hp. In the interest of weight savings the crankcase was aluminum, whilst the separate cylinders were steel and bolted onto the crankcase. Unlike previous designs each cylinder had a separate water jacket.

Flaws Emerge

Several problems were discovered during the D.III’s introduction. The first of which was the placement of the aerofoil shaped radiator above the cockpit. Although it was well placed to avoid battle damage, it tended to scald the pilot if there was a leak or puncture in the radiator for any reason. The design was changed to relocate the radiator right of the cockpit.

Albatros D.III - Wrecked at FlandersAnother issue had to do with several lower wing failures. Even The Red Baron himself, Manfred von Richthofen experienced this with a crack appearing on his new D.III and was forced to make an emergency landing.  Initially this puzzled engineers and was attributed to poor workmanship during manufacturing, but in reality the lower wing was experiencing excessive flexing under aerodynamic load. The eventual cause was determined to be the wing’s spar which was located too far aft. As a result of the changeover to the sesquiplane layout, only a single spar was used in the lower wing. Modifications were made to the design and existing aircraft to strengthen the wing. In spite of the modification pilots were advised to avoid steep or prolonged dive maneuvers.

Performance

The D.III was well regarded among pilots from its introduction despite having heavier controls. It offered improved stability, maneuverability, and climbing ability over the preceding D.II. Downward visibility was also much improved thanks to the narrower lower wing.

Bloody April

Albatros DIII - Climbing

The Albatros D.III was the most dominant fighter in the air during April 1917. The British forces attacking at Arras, France pushed for strong air support in the battle, but were their pilots were not nearly as well trained as the German pilots. To make matter worse, the British planes in use such as the Sopwith Pup, Nieuport 17, and Airco DH.2 were vastly inferior to the D series aircraft in use by the Germans. The British would go on to lose 275 aircraft. By contrast the Germans only lost 66 aircraft during the conflict.

Albatros D.III Specifications
Wingspan  9 m / 29 ft 6 in
Length  7.33 m / 24 ft 1 in
Height  2.9 m / 9 ft 6 in
Wing Area 23.6 m² / 254 ft²
Engine 1 water cooled inline Mercedes D.IIIa engine
Maximum Take-Off Weight 886 kg / 1,949 lb
Empty Weight 659 kg / 1,532 lb
Maximum Speed 175 km/h / 109 mph
Range 480 km / 300 mi
Maximum Service Ceiling 5,500 m / 18,000 ft
Crew 1 (pilot)
Armament 2 x 7.92 mm LMG 08/15 machine guns

Gallery

Sources

Albatros D.III. (2016, March 1). In Wikipedia, The Free Encyclopedia., Avistar.org (n.d.) Albatros D.III Images: Albatros D.III – Flying by DeciBit, Albatros D.III – Side View by Serge Desmet / CC BY-SA 1.0

Sopwith Camel B3889 - Side Profile View

Sopwith Camel

Great Britain, WW1, , , , , ,

british flag Great Britain (1917)
Fighter Plane – 5,490 Built
The legendary Sopwith Camel was the successor to the earlier Pup. The Camel utilized a biplane design and twin synchronized Vickers machine guns. It first flew in late 1916 as the British continued to develop faster and more powerful fighters to keep pace with  German advances in aeroplane design. The Camel was deemed far more difficult to fly than the preceding Pup and Triplane, but despite this would go on to shoot down more German aircraft than any other Allied plane.

Development

After combat losses, it became apparent that the Pup and Triplane were no longer competitive against the German Albatross D.III.  Sopwith Chief Designer Harry Smith recognized the need for a new fighter to be developed. While being designed, the Camel was referred to as the F.1 or the “Big Pup.”

Sopwith Camel - Front ViewAs was standard at the time, the airframe was a wood boxlike structure, with aluminum cowlings around the nose and engine area. Metal wire rigging was used throughout the construction to enhance fuselage and flight surface rigidity. A conventional fabric covered body and plywood cockpit area ensured weight savings were maximized. The nickname of “Camel” came from a “hump” shaped metal fairing that covered the machine guns in order to prevent freezing at altitude. The F.1 was also sometimes referred to as the “Sop,” short for Sopwith. The lower wings featured a dihedral of 3 degrees, meaning the wings are angled upwards and are not perpendicular to the fuselage. However to simplify construction the top wing was flat, giving the plane a unique “tapered gap” between the upper and lower wings. Also the top wing features a cutout section above the cockpit for pilot visibility.

The Camel

After its introduction in June 1917, the Camel became notorious for being difficult to fly. Rookie pilots crashed many times upon takeoff. Part of the reason was the fact that the center of gravity of the plane was very close to the nose owing to the plane’s sizeable powerplant relative to the size of the airframe.  However the fact that 90% of the weight of the aircraft was in the front third of the aircraft gave it great maneuverability, with the weight of the engine, pilot, and armaments centered within the wing root section of the fuselage.

Sopwith Camel Replica - ParkedThe Camel lacked the variable incidence tailplane and trimming that had enabled the Triplane to fly “hands off” at altitude. This meant that a pilot would have to constantly apply pressure to the control stick to maintain level flight at low altitude or speed. Great physical strength and endurance was required to fly the Camel at length.

The Camel had a rotary engine, not to be confused with a radial engine or a rotary wankel. With a rotary engine, the entire engine and crankcase spins relative to the fuselage, with the propeller directly connected to the crankcase. Thus engine speeds in RPM exactly the match the RPM of the propeller. The torque of the relatively powerful rotary engine combined with the weight distribution of the aircraft led to a constant “pull” to the right, a phenomenon common to rotary engines.  Although not necessarily a desired feature, pilots used this to their advantage for turning in dogfights. However, in the event of a stall the Camel would go into a dangerous spin.

The difficulty of flying the aircraft is obvious from the fact that about half of all Camels lost during the Great War were due to non-combat related incidents.  Early on there were many pilot casualties on their first solo fights after training, so a two-seat, dual control version was developed to mitigate the dangers of training on the aircraft.

The Numbers

A staggering 5,490 Camels were produced. Most were deployed to the Western Front. After the war they did not see much use in service. Remarkably only 7 are known to exist as of 2016, however there are many flying replicas of the aircraft.

The Camel is credited with downing 1,294 German aircraft, more than any other Allied plane. Among the plane’s kills is the famed German ace Rittmeister Manfred von Richthofen also known as the “Red Baron.”

Power

The Camel was powered by a variety of rotary engines and by design was able to be fitted with engines from other manufacturers such as Bentley. The primary engine used was the 130 HP Clerget 9B, a French design produced in France and Great Britain which also saw service in the Pup and Triplane.

The most powerful engine available was the Bentley BR1 which produced 150 HP thanks to its aluminum cylinders and pistons as well as a dual spark ignition. It was also significantly cheaper than the Clerget.

Sopwith Camel Specifications
Wingspan  8.5 m / 28 ft 11 in
Length  5.7 m / 19 ft 8 in
Height  2.6 m / 9 ft 6 in
Wing Area 21.5 m² / 231.42 ft²
Engine 1 air-cooled Clerget 9B 110 HP or 130 HP
Maximum Take-Off Weight 659 Kg / 1.453 lb
Empty Weight 422 kg / 930 lb
Maximum Speed 185 km/h / 115 mph
Range 350km / 217 mi
Maximum Service Ceiling 5,790 m / 19,000 ft
Crew 1 (pilot)
Armament 2 synchronized 7.7mm Vickers machine guns
4 20lb Cooper bombs

Gallery

Sopwith Camel B6313 - March 1918
Sopwith Camel B6313 – March 1918
Sopwith Camel B6313 - 6-1918 '3 Stripe' - Side Profile View
Sopwith Camel B6313 – June 1918 – ‘3 Stripe’
Sopwith Camel B6299 - B Flight, 10 Naval Squadron RNAS
Sopwith Camel B6299 – B Flight, 10 Naval Squadron RNAS
Sopwith Camel B6390 'Black Maria' - Raymond Collishaw
Sopwith Camel B6390 ‘Black Maria’ – Raymond Collishaw
Sopwith Camel B6313 - October 1918 - '6-Stripe'
Sopwith Camel B6313 – October 1918 – ‘6-Stripe’
Sopwith Camel B6313 - Oct 1917 Side Profile View
Sopwith Camel B6313 – October 1917
Sopwith Camel B3889 - Side Profile View
Sopwith Camel B3889 – July 1917
Sopwith Camel F6034 - Side Profile View
Sopwith Camel F6034 – September 1918
Sopwith Camel B6344 - October 1917
Sopwith Camel B6344 – October 1917

Sources

Sopwith Camel. (2016, April 1). In Wikipedia, The Free Encyclopedia, Avistar.org (n.d.) Sopwith Camel 1917, Sherman, S. (2012). Sopwith Camel, Franks, N. (2001). American aces of World War I. Oxford: Osprey Aviation. Images: Sopwith Camel – Front View Lineart by Voytek S / CC BY-SA 1.0, Sopwith Camel – Replica in Flight by D. Miller / CC BY 2.0, Sopwith Camel – Replica Structure by TSRL / CC BY-SA 3.0

SAAB Gripen Armed In Flight

Saab J39 Gripen

Modern Aviation, Sweden Modern, , , , , , , ,

sweden flag Sweden (1997)
Multirole Fighter Plane – 247 Built
A light single-engine multirole fighter, with a delta mid-wing and canard configuration. This aircraft has a fly-by-wire flight controls. Purposed with replacing the Saab 35 Draken and Saab J 37 Viggen AJ, SH, SF and JA versions in service with the Flygvapnet (the Swedish Air Force), and in service since 1995. Its development began in the late 70’s, with the aircraft intended to perform the same missions of the models it was replacing. As a result, the Gripen is capable of executing missions as fighter, attacker, and reconnaissance, being also a cheap yet well-powered and highly manoeuvrable jet, capable of integrating well with the Flygvapnet communication and infrastructure systems. It is also a platform with good upgrading capacities. Another special feature of this model is the short take-off and landing (STOL), alongside its agility and responsiveness at subsonic speeds, low induced drag and good supersonic performance. A product of Swedish innovation and defence needs, allowing Sweden to maintain its neutrality during the Cold War, the aircraft’s STOL characteristic came as a result of the policy of using highways and roads as airstrips, in order to reduce the potential damage to Flygvapnet air assets in case of attack, and to maintain air defence capacity. It was also intended to be an easy maintenance airplane, with conscripts having basic technical knowledge being able to do maintenance works. This increases the aircraft’s service life.

Design

The Gripen is designed as a mid-delta wing fighter, with a single tail and a single Volvo Flygmotor RM 12 engine. It has canard winglets that also serve as complement for the two aerodynamic brakes located at the sides of the rear fuselage. The combination of the canards and the delta wing design allows the Gripen to fly at 70-80 degrees of attack angle, allowing also STOL capabilities (800 mts/2600 ft airstrip). Its purposed aerodynamic instability is compensated with a fly-by-wire technology that bestows the Gripen with considerable fly characteristics. The engine also plays its part in shaping the Gripen characteristics, along with some additional features. The double digital control and double ignition allows the pilot and the aircraft to be safe in case of emergency. The engine itself is reinforced to withstand the impact of birds or foreign objects. The radar – an Ericsson pulse-Doppler – allows the Gripen to have powerful and sharp ‘eyes’, as it allows multiple target track and beyond visual range (BVR) for air-to-air; mapping ground and surface target indication and tracking for air-to-ground; and sea surface search and tracking.

The Digital Era

SAAB Gripen Parked

The JAS 39 has a Tactical Information Data Link System (TIDLS) digital network which provides the Gripen with a tactical advantage: to distribute and share radar and sensors information with up to 4 aircraft within a radio of 480 kms (300 miles), enabling tactical combat information and situation awareness. It also provides any pilot information about the position, speed, missile load, heading and fuel state of other Gripens. This provides also concealment to any pilot opening fire against a selected target, without revealing its position, while the launched missile – a medium-range air-to-air-missile (AMRAAM) – will be guided not only by the aircraft it was fired from, but also by the other aircraft, whose guidance can improve the missile’s accuracy. TIDLS technology however, is not a product enjoyed only by the Gripen’s development, but it is an enhanced version, as the JAS 35 Draken and JAS 37 Viggen had a similar and early datalink systems. As it is a multirole aircraft, this means it can change its mission while flying, as the pilot change the avionics and sensors in flight. Although the small size of the plane limits these capacities and payload, forcing missions to be considered before sorties, it also allows the aircraft to reduce detection by radar.

The Gripen goes to Battle 

SAAB Gripen Armed In Flight

The high adaptability and capacity of the aircraft to be easily upgraded allowed the Gripen to be modified in order to fit NATO standards, and to increase its export options. Alongside the British BAE, Saab improved and modified the Gripen so to be able to operate with NATO missiles, opening the open for the aircraft to carry more powerful missiles, and having also enhanced air-to-ground capabilities. Those modifications allowed the Gripen to support NATO intervention in Libya (Operation Unified Protector) with tactical air reconnaissance, enforcement of the no-fly zone, the arms embargo, and support for civilian protection. It was also able to receive updates and information from NATO E-3 AWACS airplanes. The Gripen performance was optimal during the operation, as it flew 570 missions, around 1770 flight hours, and delivered 2770 reports.

A Coveted Fighter

Saab Gripen Taxiing

Given its characteristics and its good relation cost/operation, the Saab JAS 39 Gripen has received the attention of many countries that expressed their interest in the fighter. Countries like Argentina, Austria, Belgium, Botswana, Bulgaria, Colombia, Croatia, Ecuador, Estonia, Finland, India, Indonesia, Kenya, Latvia, Lithuania, Malaysia, Mexico, Namibia, Peru, The Philippines, Portugal, Serbia, Slovakia, Slovenia, Uruguay, and Vietnam, all could become potential operators of the Gripen.

Variants

  • JAS 39A – The basic and first version entering in service with the Flygvapnet, later upgraded to the C version.
  • JAS 39B – The two-seated variant of the JAS39A, purposed for training, specialised missions and flight conversion, with the cannon and the internal fuel tank removed to allow the second crew member and life support systems.
  • JAS 39C – A NATO-compatible version with overall enhanced capabilities, as well as in-flight refuel.
  • JAS 39D – The two-seat version of the JAS 39C.
  • JAS NG – An improved version of the Gripen, having a new engine (The General Electric F414-400), a new radar (RAVEN ES-05 AESA), and increased payload and fuel capacity. Its development was undertaken through a partnership with Switzerland. A product of the changes brought by the end of the Cold War, as airbases were closed with fighter units being reduced, as well as the closure of the road base system for take offs and landings. But it is also a product of the new assessed threat Sweden could be facing, which required a new fighter with extended range, increased weapons, enhanced electronics, fighter communications (with satellite) and Electronic Warfare (EW) capability.
  • JAS 39E– Single seat version derived from the JAS NG.
  • JAS 39F – Two-seat version derived from the JAS 39E.
  • Sea Gripen – Proposed carrier version of the NG.
  • Gripen UCAV – Proposed unmanned combat version of the JAS 39E.
  • Gripen EW – Proposed electronic warfare version derived from the JAS 39F.

Operators

  • Brazil – 28 Gripen JAS 39E and 8 Gripen JAS 39F on order, with options of assembling some locally, while the Brazilian Navy is interested in the Sea Gripen for use on its single aircraft carrier. Brazil could export Gripen into the regional market. There is a provision for joint development with Sweden.
  • Czech Republic – 14 Gripens on lease (12 JAS 39C and two JAS 39D) until 2027 and to replace the existing Mig 21 fleet. given the current tensions between the West and Russia, Czech Republic government considered leasing 6 more Gripens. Gripen have had a good use by the Czech Air Force, with membership of the NATO Tiger Association, awarding the Tiger Meet Silver Tiger Award as ‘Best Squadron’. Gripen from Czech Republic also take part in NATO Baltic Air Policing, while performing homeland defence duties at the same time.
  • Hungary – 12 Gripens on a lease-and-buy basis (11 JAS 39 C and one JAS 39D) until 2022. Two Gripens lost in crashes. Hungarian Gripens have been taking part of NATO Baltic Air Policing since 2015.
  • South Africa – 26 Gripens are in service with the South African Air Force (17 JAS 39C and 9 JAS 39D), facing restricted operation given lack of qualified pilots and financial resources. However, South African Gripens enjoyed a local EW development – in cooperation with Israel – and datalink, as well as radar weather mode. The Gripens saw action when securing South African airspace during the FIFA 2010 World Cup, supporting South African troops in the Democratic Republic of Congo in 2013, and taking part in Nelson’s Mandela funeral.
  • Sweden – The Flygvapnet has 156 Gripen, 50 of which are JAS 39A, 13 are JAS 39B, 60 are JAS 39C and 11 are JAS 39D. Two (a JAS 39C and a JAS 39D) were lost in accidents.
  • Thailand – 12 Gripens (8 JAS 39C and 4 JAS 39D) serve with the Thai Air Force, where eventually 6 more Gripen would be bought. As these Gripen operate over the Andaman Sea and Gulf of Thailand, they have anti-ship capacities.
  • United Kingdom – Operated by the Empire Test Pilots’ School, with 3 JAS 39B, with training and testing purposes.

Gripen Specifications
Wingspan  8.4 m / 27 ft 7 in
Length  14.10 m / 46 ft 3 in
Height  4.7 m / 14 ft 9 in
Wing Area 30 m² / 323 ft²
Engine 1 Volvo Flygmotor turbofan RM12
Maximum Take-Off Weight 14000 Kg / 30,900 lb
Empty Weight 6800 kg / 15,000 lb
Loaded Weight 8500 kg / 18,700 lb
Maximum Speed 2450 km/h / 1522 mph
Range 3250 KM / 1,983 miles (with external drop fuel tanks)
Maximum Service Ceiling 16000 m /52,500 ft
Climb Rate 100 s from brake release to 10 km altitude / 180 s approx to 14 km
Crew 1 or 2
Armament • 1 Mauser BK 27 27mm cannon
• 6 hardpoints that could allow 6 air-to-air missiles, 4 air-to-radar missiles, 4 air-to-surface missiles, 5 smart bombs, 2 anti-ship missiles, 5 bombs, 2 stand-off weapons, 2 ECM Pods, 2 recce Pods, 1 FLIR/LDP Pod, 2 AACMI Pods, and 3 fuel tanks

Gallery

J39C Gripen of the Flygvapnet – Swedish Air Force armed with wingtip IRIS-T Missiles
J39C Gripen of the South African Air Force equipped with a wing drop tank and IRIS-T missiles

Sources

Berger, R (Ed.). Aviones [Flugzeuge, Vicenç Prat, trans.]. Colonia, Alemania: Naumann & Göbel Verlagsgessellschaft mbH. , Hellenius, B (March 2014). Griffin Takes Wing. Air Forces Monthly, (312), 50-65. , SAAB (March 2016). Gripen brochure. , SAAB (n.d.). Gripen-Advanced Weapons Flexibility. , SAAB (n.d.). Gripen dimensions. , Singh, V (May-June 2014). The Gripen forges ahead – in ‘Super’ mode. VAYU Aerospace & Defence Review, (3) 61-65.  , Sharpe, M (2001). Jets de Ataque y Defensa [Attack and Interceptor Jets, Macarena Rojo, trans.]. Madrid, Spain: Editorial LIBSA (Original work published in 2001). , Wikipedia:Saab JAS 39 Gripen Images: SAAB Gripen Taxiing by Airwolfhound / CC BY-SA 2.0 ,  SAAB Gripen Parked by Milan Nykodym / CC BY-SA 2.0 , SAAB Gripen Armed in Flight by AereiMilitari.org / CC BY-NC 2.0