Tag Archives: Concept

Official classification tag

Hütter Hü 136 Stubo

Weimar and Nazi Germany, WW2,

Nazi flag Nazi Germany (1938)
Armored Ground Attack Aircraft – 1 Replica Built

Stubo I Replica [aviationmuseum.eu]
The Hütter 136 was an interesting concept for a ground attack aircraft that employed numerous experimentations in its design. The cockpit was fully armored, the landing gear was replaced by a skid, and the entire propeller would be jettisoned off during landings. The aircraft came in two forms: the Stubo I, a short design with the ability to carry an external 500 kg bomb, and the Stubo II, a lengthened version that could carry two internal 500 kg bombs. The program never progressed as far as production and work stopped on the project shortly after the Henschel Hs 129 was ordered for production.

History

Artist’s Impression of the Stubo I [Heinz Rodes]
During the years leading up to the Second World War, Nazi Germany found itself needing a competent air force to rival those it would soon face. Restrictions set by the Treaty of Versailles severely hindered the German military both in size and equipment in order to ensure that German power would not threaten the continent again, as it did during the First World War. History notes that the Germans broke this treaty, at first covertly and then overtly, with the Allies showing no response or protestation to the blatant violations. Germany began amassing a massive military force in preparation for war. New programs and requirements were laid down in preparation for the inevitable war. These projects included many newly tested concepts, such as dive-bombing. The Junkers Ju-87 Stuka proved the effectiveness of dive bombing in the Spanish-Civil War, with a famous example being the Bombing of Guernica, but a newer attacker was eventually needed to complement it. An order in 1938 was put out by the Reichsluftfahrtministerium (Aviation Ministry, “RLM”) to develop a new armored ground-attacker. One of the companies that would participate in this requirement would be Hütter.

2-way and cutaway of the Stubo II

The designs of Ulrich and Wolfgang Hütter are relatively unheard of when it comes to aircraft. They began their aviation career designing glider aircraft in the 1930s, such as the popular Hü 17, some of which were used post-war. The Hütter brothers built a career in designing aircraft for the Luftwaffe (German Air Force) between 1938 and 1944 under the codename of Ostmark. The two began working on the project mentioned before for an RLM request for a new ground-attacker in 1938. The requirement laid down very specific guidelines to be followed. The new aircraft needed to have good flight performance and an armored airframe for extra protection, as well as enough speed to evade fighters. In preparation for the new designs, the RLM notified designated factories that would begin to produce these airframes upon adoption into service. The Hütter brother’s response would be the Hü 136. Other competitors included the Henschel Hs 129 and the Focke-Wulf Fw 189V-1b, an armored ground attack version of their reconnaissance plane. Not all projects for a new attacker were armored at this time. Other new designs included the Junkers Ju 187 and Henschel Hs P 87.

The Hütter Hü 136 was nicknamed the Stubo, a shortened version of the name Sturzbomber (Dive Bomber). The aircraft itself would be a single-engine design. Two versions of this aircraft existed. The first, Stubo I, was meant to fill the need for a heavily armored attacker and would be used in ground-attack and dive-bombing tactics. The second was the Stubo II, a two-seater which was essentially a longer version of the Stubo I and carried twice the bomb load internally. The flight performance of the Stubo II was estimated to be the same as that of the Stubo I although, given the design characteristics, that estimation is highly doubtful. The two designs did not meet the requirements for bomb load and range. To make the aircraft more efficient, the brothers took an interesting design change. Taking a note from their glider designs, they removed the conventional landing gear and replaced it with an extendable landing skid, which made the aircraft lighter and freed more space for fuel. This, however, posed serious designs problems. The Hü 136 now had to take off using a detachable landing gear dolly, similar to how the Messerschmitt Me 163B rocket plane would take off a couple years later. Due to this, the propeller would not have enough clearing and would hit the ground during landings. To fix this, the two brothers made the propeller detachable. During landings, the aircraft would eject the propeller, which would gently parachute to the ground above an airfield for recovery and reuse. To assist in landings, a new surface brake was also added to the aircraft.

2-way and cutaway of the Stubo I

The far more conventional Henschel Hs 129 would be designated the winner of the competition. Subsequently, no construction was ever started on either the Stubo I or II. The Stubo proved to be an interesting but flawed concept. The limited visibility from the armored cockpit would negatively affect the aircraft in all operations. Dogfighting, bombing and even flying in general would be affected by the cockpit’s design. The change in landing gear design may have extended the range and lowered weight, but pilots now had to learn how to land using a skid. The fact the entire propellor evacuated the aircraft was a huge issue in itself. Once ejected, the landing could not be aborted, and if the landing attempt failed, there was no chance to loop around and try again.

This, however, would not be the last project designed by the Hütter brothers for the Luftwaffe. Wolfgang would begin working on a long-range reconnaissance version of the Heinkel He 219 called the Hütter Hü 211. Another project is the rather unknown Hütter Fernzerstörer (Far Destroyer), a long-range turboprop attacker meant to be used on the Eastern Front. With the war ending, no further Hütter aircraft were designed. One would think the story of the Stubo ends with its cancellation, but the story continued rather surprisingly recently. The Military Aviation Museum in Virginia Beach, VA, acquired a full-scale replica of the Stubo I in 2017 and it is currently on display in their German Experimentals section, along with full-scale replicas of other “Luft 46” designs.

Design

The Stubo I was a single-engine armored ground attacker. In the front, it mounted a detachable propeller and a Daimler-Benz DB 601 inline engine. In the fuselage, a large gap was present between the engine and cockpit. This was most likely the fuel tank where the fuel tank was placed. Beneath the aircraft, a single 1010 Ibs bomb (500 kg) was mounted on an external hardpoint. This hardpoint most likely would be in the way of the landing skid, implying the payload had to be dropped before making an attempt at landing. For takeoff, a dolly would have to be mounted beneath the aircraft. This would be jettisoned shortly after the Stubo would be airborne. For landing, the aircraft would use an extendable skid. The wings of the aircraft had slight dihedral, which meant the wings were angled upward from the body. The Stubo I had an armored steel cockpit that was completely enclosed. For visibility, a small sight in the front and two side portholes were given. Had the aircraft been produced, peripheral vision would have been nonexistent and dogfighting would have been near impossible if it needed to defend itself. Normal operations, such as navigation and landing would have also been hindered, while combat operations such as target acquisition and attack run planning would have been exceedingly difficult. A tailfin was mounted directly behind the cockpit and not in a conventional tail design. Sources also mention the Stubo I would have mounted machine-guns, but the plans do not show exactly where or of what type these would have been.

Artist’s Impression of the Stubo II [Heinz Rodes]
The Stubo II was virtually identical to the Stubo I, aside from its extended fuselage. This lengthened design would allow the Stubo II to carry two 1010 Ibs (500 kg) bombs in a bomb bay, compared to the single bomb carried on a hardpoint by the Stubo I. Among smaller differences, the Stubo II’s wings had no dihedral compared to the angled dihedral of the Stubo I. With the lengthened fuselage, the landing skid was also extended to accommodate the longer airframe. It most likely also carried over the machine guns used on the Stubo I. The Stubo II uses nearly identical sized wings to the Stubo I, which gives the Stubo II a rather odd design, having the body lengthened but the wing size remaining the same. This would have definitely affected performance and possibly would have made the aircraft more unstable in maneuvering with the extra weight.

Variants

 

  • Stubo I – Armored ground-attacker that would carry a single external 500 kg bomb. Sources also mention machine guns, but documents don’t show where exactly they would have been located.
  • Stubo II – A lengthened version of the Stubo I, the Stubo II had an internal bomb load of two 500 kg bombs.

 

Operators

 

  • Nazi Germany – If the Hütter 136 would have entered production, Nazi Germany would have been the main operator of the craft.

Hütter 136 “Stubo I” Specifications
Wingspan 21 ft 4 in / 6.5 m
Length 23 ft 7 in / 7.2 m
Height (estimate) 5 ft 3 in / 1.6 m
Engine 1x 1,200 hp (894 kW) DB 601 Inline Engine
Loaded Weight 8,160 lbs / 3,700 kg
Maximum Speed 348 mph / 560 km/h
Range 1,240 mi / 2,000 km
Maximum Service Ceiling 31,170 ft / 9,500 m
Crew 1 pilot
Armament
  • 1x 1010 lbs (500 kg) bomb
  • At least 2 machine guns of unknown type (Most likely MG 15 or MG 17)

Gallery

Illustrations by Haryo Panji https://www.deviantart.com/haryopanji

Stubo I Side View [Haryo Panji]
Stubo II Side View [Haryo Panji]

Sources

Martin-Baker Tankbuster

UK, WW2, ,

UK Union Jack United Kingdom (1942)
Anti-Tank Aircraft Design – None Built

3D artist impression of the Tankbuster in flight [candymountain.jp]
The Martin-Baker Tankbuster was a concept British anti-tank aircraft that was designed according to an order in 1942 for a specialized ground attacker. The aircraft had a twin-boom, pusher design and was only armed with a 6-pounder (57mm) cannon, most likely a Molins M-Class Gun. Compared to its competitors, the Tankbuster was strictly limited to exactly what it was named for; busting tanks, and would find itself having trouble against other ground targets or even defending itself. With the program being canceled in early 1943 and Martin-Baker working on more important projects, all work stopped on developing the Tankbuster any further.

History

Drawing of the Martin-Baker Tankbuster [British Secret Projects]
In early 1942, the Royal Air Force began seeking a new ground-attack aircraft that would replace the 40mm-armed Hawker Hurricane Mk.IID. An order was officially placed on March 7th for a specialized ground attacker that would be used against a multitude of targets including ground units, enemy aircraft, transports/shipping, and a main focus on destroying tanks. To accomplish the destruction of the aforementioned targets, the aircraft was meant to use more heavier guns than the Hurricane Mk.IID. Alternative weapon arrangements included: three 40mm Vickers S cannons, four 20mm Hispano Mk.V cannons, a combination of two 20mm with two 40mm cannons, six unguided rocket (RP) racks with two 20mm cannons or one 47mm Vickers gun with two 20mm cannons. Two 500Ibs bombs could also be added. The expected speed for the design had to reach at least 280mph (450 km/h) at 3,000ft (900 m). Visibility was also a necessity and forward view had to be unobstructed and clear. Full production was to be expected by 1944. The programs would be overseen by the Air Staff.

Over 10 different designs by several aircraft companies were subsequently created for this program. A majority of them were of unorthodox design. Armstrong-Whitworth (AW.49) and Boulton-Paul (P.99) both created twin boom designs. Boulton-Paul also submitted a canard design labelled P.100 and a biplane design labelled P.101, the latter being seen as a safe alternative to the radical canard and twin boom designs prevalent through the program. Perhaps the most interesting of the designs was the submission by Martin-Baker.

3D artist impression of the Tankbuster [candymountain.jp]
At the time of its submission, Martin Baker had been working steadily on their MB.5 project, which would eventually become one of the best performing piston aircraft built by Britain, but this wouldn’t be completed until 1944. Their design for the ground attacker was submitted several months after the order was given by the Air Staff and was only named the “Tankbuster”. Martin Baker’s concept was for a twin boom design that deviated extensively from the given requirements. The aircraft was armed with a single 6-pounder (57mm) cannon, and the aircraft would be completely encased in 1/2-inch armor. The armor itself weighed 4,900Ibs (2,200kg).

The project wasn’t very impressive nor reasonable in the eyes of the Air Staff, especially compared to the other designs in the program. Its single large-caliber gun extremely limited its target range and it would only have been able to attack one of six predicted target types the program requested. The aircraft lacked any other offensive or defensive armament and would rely on its armor alone to protect itself, a gambit that other designs in the program resolved by following the armaments listed by the Air Staff. Attempts to add more ordnance such as additional guns, rockets or bombs to the wings would have added too much stress on the airframe. The main feature of the aircraft was the root of its problems, its gun. The gun itself couldn’t be removed from the airframe and an aircraft going into battle with a single weapon would be inefficient for resources. The Tankbuster didn’t meet the armament expectations and fell under the expected speed by 10mph (16 km a h). On April 15th, 1943, Air Marshall F J Linnell (who was a good friend of James Martin, a founder of the company) advised Martin-Baker to drop development of the Tankbuster in favor of continuing work on the more successful MB.5 project going on at the same time.

Near the later days of April 1943, the Air Staff brought the program the Tankbuster was designed for to an end. They concluded that, at the time, developing and producing an entirely new ground attack aircraft would impede the current war programs and that the submissions were too specialized in design compared to modifying aircraft already being produced for ground attack duties. One such aircraft they pointed to was the Hawker Hurricane Mk IV, a ground attacker version of the famous fighter which was performing successfully in the role and had started production in March of 1943. Later additions to the ground attack role would be the Hawker Typhoon, which became a scourge to German ground troops. Even if the program had continued towards production, it was significantly unlikely the Tankbuster would have been chosen for the role. The aircraft was way too specialized and disliked by the Air Staff, and Martin Baker was working on an aircraft that would yield much better results. Although the Tankbuster may have been the runt of a doomed program, it still proves to be an interesting, albeit flawed solution in the name of destroying enemy armor.

Design

The Martin-Baker Tankbuster was a twin-boom single-engine design. The aircraft would have been constructed entirely of metal. The airframe itself would be covered in an additional 1/2-inch (12.7mm) armor. This armor would weigh 4,900Ibs (2,223kg) on its own. The armor covered the entire body and also the engine cowling. What’s interesting to note is that the aircraft had two engine intakes, one facing forward and one facing the rear. The radiator and oil tank were mounted in the frontal fuselage. The radiator itself was armored by offset plates that would prevent bullets from ricocheting inside. The cockpit area had clear forward visibility, and would seat a single pilot. The canopy would most likely have had bulletproof glass to complement the rest of the armored body. For it’s engine, the Tankbuster would have mounted a Griffon II engine in pusher configuration. This is relevant to Martin-Baker’s other project, the MB.5, as this aircraft also used the Griffon. The reason the aircraft utilized a pusher configuration was it gave the pilot clear visibility in the front and the gun could be placed directly forward. The pusher configuration isn’t common because of the fact that it leaves the engine open to enemies that are chasing the aircraft. This would have been especially deadly for the Tankbuster, given it has no defensive armament. The tail section and wings would also be constructed of metal. The wings were wide to improve low level flight. There was an attempt to diversify the targets by adding additional weapons to the wings, but this would only overload them. The Tankbuster had a fixed tricycle landing gear. This decision was made to conserve interior space but would have slowed the aircraft considerably. The only armament the aircraft would have been armed with would be a 6-pounder cannon (57mm) that would be frontally mounted, supplied with 30 rounds of ammunition. The aircraft would only be allowed to target heavily armored targets. To assist in aiming, the gun was placed towards on horizontal axis. This would prevent the aircraft from pitching when the gun was fired.

Role

The Tankbuster’s design might seem odd by conventional aircraft standards, but every single feature the aircraft had was to assist in it’s role of attacking enemy armor. Long, flat wings would give the aircraft an edge in low-level flight. The pusher engine would give the aircraft a clear view and nothing to obstruct the cannon. The entire airframe being heavily armored would protect against AA fire and enemy aircraft. Going into battle, the Tankbuster would need escort fighters to protect against opposing interceptors. Once in the combat zone, the Tankbuster would begin its assault on enemy tanks. The De Havilland Mosquito also mounted the 6-pounder Molins gun and was also used in the ground-attack role, but only for a short time before switching to an anti-shipping role. It is likely the Tankbuster would have also undergone this change had it entered production.

Variants

  • Martin-Baker “Tankbuster” – The only version of the Tankbuster drawn was the original design with a single cannon.

Operators

  • United Kingdom – This aircraft would have been operated by the Royal Air Force had it been produced.

Martin-Baker Tankbuster Specifications
Wingspan 47 ft 10.8 in / 14.6 m
Length 41 ft / 12.5 m
Wing Area 471.5 ft² / 43.8 m²
Engine 1x 1,730 hp ( 1,290 kW ) Griffon II Inline-Engine
Weights 12,000 Ibs / 5,440 kg
Climb Rate 2,250 feet/min / 686 meters/min
Maximum Speed 270 mph / 434 km/h
Minimum Speed 75 mph / 122 km/h
Crew 1 pilot
Armament
  • 1x 6-pounder (57mm) Molins M-Class cannon

Gallery

Illustration by Haryo Panji https://www.deviantart.com/haryopanji

Scale model of the Tankbuster [modelingmadness.com]

Sources

Gloster CXP-1001

Cold War, Republic of China, , ,

Taiwan flag UK Union Jack Republic of China / United Kingdom (1947)
Jet Fighter – 1 Mockup Built

A modern interpretation of the Gloster CXP-1001 Blueprint (theblueprints.com)

The Gloster CXP-1001 jet fighter was the result of a joint Anglo-Chinese design venture initially conducted in 1946 to provide the Republic of China with a modern and efficient jet fighter. Based on the Gloster E.1/44, the CXP-1001 would have been the first jet aircraft to enter service in China. Plagued by slow development and lack of funding, the CXP-1001 was never fully completed, although a mockup was produced. Despite the fact that the Gloster CXP-1001 was one of the most important milestones of Chinese aviation, it is relatively unknown to both the Eastern and Western world due to its obscurity.

History

With the conclusion of the Second World War, both the Communist Chinese forces under Mao Zedong and Chinese Nationalist forces under Chiang Kai-Shek were preparing themselves for the inevitable continuation of the Chinese Civil War, a conflict between the two factions that had been going on since 1927. The American Lend-Lease programme greatly assisted the modernization of the Nationalist forces during the Second World War, equipping them with contemporary weapons and vehicles. The Communist forces, on the other hand, relied on mostly obsolete weapons from the Qing-era (pre-1912). Despite this, the Nationalists expected fierce resistance from the Communists, and the fact that members from the former Imperial Japanese Army Air Service and Manchukuo Imperial Air Force were helping the Communists build up an air force alarmed the Nationalist ranks. In order to gain an upper hand on the Communists, Chiang authorized a technical mission to the United Kingdom in early 1946 to investigate the possibility of a joint Anglo-Chinese program for a fighter, a bomber and a jet fighter. After extensive negotiating, the Gloster Aircraft Company agreed to initiate a collaborative jet fighter design with China. Following an agreement on July 18th of 1946, thirty Chinese designers and engineers were to be given facilities at the Design and Drawing Offices at Hucclecote, Gloucestershire for twelve months. A team of thirty-three British designers was to reside with the Chinese in order to mentor them on improving the Chinese aircraft industry. The Chinese team arrived sometime in September of the same year and they were brought to a section of the Brockworth factory where workshops and offices were set aside for the Chinese to study the British aircraft industry. Interestingly enough, each member of the Chinese delegation was gifted an Austin 8 car for the duration of their stay. Another term of the aforementioned agreement was that, after six months, the Nationalist government could send a list of specifications to Gloster and they would design and produce three jet prototypes for them within thirty months. The prototypes would then be shipped to mainland China, where the Nationalists could decide whether or not to acquire a manufacturing licence.

During the initial days, the Chinese designers were rarely allowed to see anything of value, as the Air Ministry had, quite expectedly, declared most of the projects that were being worked on as secret. Technology such as the Gloster Meteor fighter, the Rolls-Royce Nene Mk.2 and E.1/44 fighter were all hidden from the Chinese. Despite this, the Chinese were able to negotiate a Rolls Royce Nene Mk.1 jet engine manufacturing licence, but the British Ministry of Air secretly ordered Rolls-Royce to delay the contract as much as possible.

With the worsening situation back in China, the Chinese delegate in Britain reached out to Gloster and asked them to prepare a contract for the design of a single-seat fighter aircraft powered by either the Rolls-Royce Nene or de Havilland Ghost turbojet with assistance from the Chinese engineers. As such, Gloster representatives consulted the Ministry of Air for permission to adapt the Gloster E.1/44 jet fighter to the specifications set by the Chinese, but refrain from production. This request was granted and the new aircraft proposal was assigned the designation of “CXP-102” (Chinese Experimental Pursuit) on May 14th of 1947. During development, it was noted that the situation in China worsened every day for the Nationalists and a stable aircraft industry back home would take a considerable amount of time to set up. Colonel Wu, part of the military attache and negotiator with Gloster decided to once again contact the Gloster firm with the hopes of securing a more advanced design which could be immediately exported to China for use. This time, the Ministry of Air stepped in and voiced their objections to providing a foreign air force with a jet fighter whose performance would match or even surpass the latest British fighters fielded. To make matters worse for the Chinese, more and more Gloster staff were being reassigned to work on the Gloster F.43 and F.44/46 projects, as there was a limited design capacity in the United Kingdom at the time. The Foreign Office was also hesitant on supplying a future prototype to China due to the civil war China was facing. However, they did approve of a manufacturing license as they predicted that the design was still two or three years away from completion, and that the Civil War would be over by then.

With the proposal for an already completed design rejected, Gloster and the Chinese staff began to redesign the CXP-102 to meet higher standards. This new design would be based on the E.1/44 once again, but also incorporated many parts used on the Gloster Meteor (such as the landing gear) for simplicity and quicker design. Although considered to be a clean and efficient design by the designers, the CXP-1001 was unfortunately plagued with slow development and lack of funding. By early 1949, the design was almost completed and a preliminary plan for two prototypes was made. Only a mockup and a couple of components were made before Colonel Lin (another Chinese military attache member) contacted Gloster on February 3rd to halt all work on the CXP-1001 due to the string of defeats suffered by the Nationalists. Gloster received the confirmation to halt work on February 28th but agreed to complete all unfinished blueprints and ship them to Formosa (Taiwan) along with a scale model and the mockup of the CXP-1001. The Nationalists planned to finish the work by themselves, but this would never happen as on June 12st of 1949, the British freighter Anchises was inadvertently bombed by Nationalist aircraft whilst in Shanghai. The incident soured relations between the two countries, and the British decided to freeze the blueprint and mockup shipment in October of 1950. After two years in limbo, the CXP-1001 would finally meet its fate as on November 25th of 1952, the Gloster Aircraft Company decided to dispose of all the materials on the CXP-1001 without informing the Nationalist Chinese. The Ministry of Supply (MoS) commented on this saying that disposing of the materials was justified as this was an outdated design, but also stated that they were not responsible for the actions of Gloster.

No photos of the CXP-1001 mockup or scale model are known to exist to this day but the Jet Age Museum in Staverton, Gloucestershire appears to possess official sketches of the CXP-1001 which can be seen in Tony Butler’s book British Secret Projects: Jet Fighters Since 1950. Though ultimately not making it past the mockup stage, the CXP-1001 remains one of the most important milestones of Chinese aviation history, being the first jet fighter design in which Chinese engineers were involved and would have been the first jet to enter service with the Chinese.

Misconception – Meteor or E.1/44 Variant?

One of the biggest controversies that surrounds the CXP-1001 is the debate of whether it is a Gloster Meteor variant or E.1/44 variant. Most contemporary internet sources (such as the BAE Systems Website) states that the CXP-1001 is a Meteor variant, but does not cite any sources to substantiate their claims. As mentioned earlier, most of the British technology were kept secret to the Chinese and the British refused to supply a foreign air force with an aircraft comparable or superior to the ones fielded by the Royal Air Force. This adds on to the argument that the CXP-1001 was based on the E.1/44, as stated by many credible authors with a long history of published books on aircraft (ie. Tony Butler & Derek N. James). When the CXP-1001’s blueprints are examined, it is also quite obvious that the design resembles the E.1/44 more than it does the Meteor.

Design

The CXP-1001’s design was heavily influenced by the Gloster E.1/44, essentially being a redesigned and improved variant of it. The CXP-1001 was an all-metal stressed skin jet fighter powered by a single Rolls-Royce RB.41 Nene Mk.1 engine producing 5,000 lbs / 22.2 kN of thrust and armed with four 20x110mm Hispano Mk.V cannons. The cannons would have been mounted in pairs above and below the nose intake. Each cannon would have been fed with 180 rounds, making a total of 720 rounds. The CXP-1001 would also have been able to carry two 200 gal / 757 L Drop Tanks to extend their range. Due to a lack of information, the details of the CXP-1001’s design is quite unknown and may never be found.

Variants

  • CXP-102 – Initial design concept based on the Gloster E.1/44 with estimated higher performance. The CXP-102 was redesigned into the CXP-1001.
  • CXP-1001 – Improved design based on the CXP-102 / E.1/44 which featured parts from the Gloster Meteor. Armed with four 20x110mm Hispano Mk.V cannons and powered by a single Rolls-Royce RB.41 turbojet, the CXP-1001 would have been the first jet fighter to enter service with the Chinese if it were to see production.

Operators

  • Republic of China – The CXP-1001 was designed with the assistance of the Chinese, and would have been operated solely by the Republic of China Air Force in a military capacity.
  • United Kingdom – The Gloster Aircraft Company was the main designer of the CXP-1001, and would have operated it in a testing capacity before shipping the prototype to mainland China.

Gloster CXP-1001*

* – Data taken from British Secret Projects: Jet Fighters Since 1950 by Tony Butler and Gloster Aircraft since 1917 by Derek N. James
Wingspan 38 ft 0 in / 11.6 m
Length 41 ft 9 in / 12.8 m
Height 14 ft 10 in / 4.29 m
Wing Area 360 ft² / 33.5 m²
Thickness to Chord Ratio 0.011
Wings Sweepback 20 °
Engine 1x Rolls-Royce RB.41 Nene Mk.1 turbojet (5,000 lb / 22.2 kN of thrust)
Internal Fuel Load 470 gal / 1780 L
Empty Weight 8,960 lb / 4,060 kg
Normal Weight 13,900 lb / 6,305 kg
Maximum Overload Weight 18,700 lb / 5,700 kg
Climb Rate 6,000 ft/min / 1,830 m/min at Sea Level
Service Ceiling 40,000 ft / 12,200 m
Maximum Range 410 mi / 600 km – Standard

1,000 mi / 1,600 km – With Drop Tanks
Maximum Speed 600 mph / 965 kmh at 10,000 ft / 3,050 m
Crew 1x Pilot
Armament 4x 20x110mm Hispano Mk.V cannon (180 rpg)
External Load 2x 200 gal / 760 L Drop Tanks

Gallery

Illustrations by Haryo Panji https://www.deviantart.com/haryopanji

Artist conception of the CXP-1001 in a late 1950s ROCAF livery. (Illustration by Haryo Panji)
Artist conception of the CXP-1001 in a late 1940s ROCAF livery. (Illustration by Haryo Panji)

Sources

Mitsubishi G7M “Taizan”

Empire of Japan, WW2, , , ,

 Empire of Japan (1941)
Strategic Bomber- 1 Scale Mockup Built

The Mitsubishi G7M “Taizan” (泰山/Great Mountain) was a planned long range strategic bomber for Imperial Japan’s Army Air Service. Developed out of the need for a bomber capable of striking the continental United States, the Taizan would face a series of developmental problems, ultimately leading to the cancellation of the project.

History

Prior to the start of World War II, Japan had foreseen that in a potential future conflict with the United States, it would require a long range bomber capable of striking the US mainland. In order to fulfill this requirement, a review was conducted in 1941 of all the Imperial Japanese Navy’s bomber aircraft in service. It was revealed that the entirety of the Japanese bomber arsenal was incapable of striking targets in the United States from the Japanese airfields. The Mitsubishi G4M “Betty” was one of Japan’s newest aircraft being pushed into service. Despite its superior range of 3,749 mi (6,043 km) compared to previous IJN bombers, it still was not sufficient enough to strike the US mainland or targets deep in the Soviet Union. As a result of this, the Naval Kōkū Hombu (Aviation Bureau) issued the 16-shi specification in 1941 for a long range bomber. The 16-shi specification would call for a bomber capable of flying at least 361 mph (580 km/h) with a maximum range of 4,598 mi (7,340 km).

Interested in this specification, Mitsubishi’s staff began work on a design that would meet the criteria set by the Kōkū Hombu. Mitsubishi engineer Kiro Honjo (the designer of the G3M and G4M) proposed a four engine design, but this was promptly rejected by the Kōkū Hombu. As a result, another Mitsubishi engineer by the name of Kijiro Takahashi submitted his own design. Upon inspection by the Kōkū Hombu, Honjo’s design was approved and given the green light to proceed. Within Mitsubishi, the 16-shi design was known as the “M-60”. Takahashi’s design was to be powered by two “Nu” engines. The Nu was a 24 cylinder liquid cooled engine which was able to provide 2,200 hp at 16,404 ft (5,000 m) but, due to the start of Operation Barbarossa, Germany was unable to export machinery and tools needed to manufacture the Nu engine. Unfortunately for Takahashi, this turn of events would prevent his design from being completed. As a result of this, Takahashi fell out with the Kōkū Hombu and Kiro Honjo would take over the M-60 project. This time, Honjo followed the Kōkū Hombu’s suggestion and used two engines instead of his idea of four. Under Honjo’s lead, the Taizan’s power plant was changed to two 18 cylinder Mitsubishi Ha-42-11 engines capable of generating 2,000 hp each. It was also seen that Honjo’s design was less aerodynamic than Takahashi’s due to the weaker engines and heavier armament.

On October 31st of 1942, an evaluation was conducted on the work done so far, and a performance estimation gave the Taizan a range of 3,454 mi (5,559 km) and a speed of 332 mph (518 km/h) at 16,404 mi (5,000 m). Falling short of the original 16-shi specification, Mitsubishi scrambled to make adjustments but further revised estimates stated that the design didn’t see any improvements, and actually saw some deterioration. By the time the Taizan’s design was completed in late 1942 and ready for construction of a wooden mockup, a new 17-shi specification was released calling for a new bomber design. Kawanishi took up the design and created the K-100 bomber project. Seeing promise and a better alternative to the Taizan, the Kōkū Hombu ordered all work on the Taizan to be halted until the K-100 could be completed and evaluated. Kawanishi completed initial work on the K-100 and a comparison was made between K-100 and Taizan in the summer of 1943. The Taizan’s range differed significantly from the proposed normal range from 2,302 mi (3,705 km) to 1,726 mi (2,778 km). Due to the significant range reduction, the Kōkū Hombu stopped supporting the Taizan. With no more interest and reason to develop the Taizan, Mitsubishi would finally shelve the project and stop all work on it.

Design

From an exterior aesthetic point of view, the Taizan bears a striking resemblance to the German Heinkel He 177. The nose of the Taizan was rounded and glazed over, a new design not in use by any Japanese bombers at the time. The wings of the Taizan were mounted mid fuselage, and were to be constructed out of metal. Fabrics, however, were to be used for the cover of the Taizan’s ailerons and rudder.

Ordinance wise, the Taizan was to carry a maximum bomb load of 1,764 lbs (800 kg). The defensive armament underwent several changes. Takahashi’s Taizan design was to be armed with two 20mm Type 99 Mk.2 cannons and two 7.7mm Type 97 machine guns. Honjo’s initial design would carry two 20mm Type 99 Mk.2 cannons, two 13mm Type 2 machine guns and two 7.92mm Type 1 machine guns. Later on, the armament finalized at two 20mm Type 99 Mk.2 cannons and six 13mm Type 2 machine guns. There would have been one Type 99 Mk.2 in the nose and one in the tail. There would have been two Type 2 machine guns in the forward upper fuselage turret, two in the rear fuselage turret and two in ventral position, firing rearwards.

Operators

  • Empire of Japan – The Taizan would have been operated by the Imperial Japanese Navy Air Service.

 

Mitsubishi G7M1 “Taizan” *

*Estimated performance of Mitsubishi’s G7M1 proposal
Wingspan 82 ft / 25 m
Length 65 ft 6 in / 20 m
Height 20 ft / 6.09 m
Engine 2x Mitsubishi Ha-42-11 (2,000 hp)
Power Loading 8.8 lbs/hp / 3.99 kg/hp
Empty Weight 23,368 lbs / 10,600 kg
Usual Weight 35,273 lbs / 16,000 kg
Fuel Capacity 4,497 L / 1,188 US Gallon
Climb Rate 32,808 ft / 10,000 m in 10 minutes
Maximum Speed 344 mph / 544 kmh @ 26246 ft / 5,000 m
Typical Range 1,739 mi / 2,799 km
Maximum Range 4,598 mi / 7,400 km
Crew 7
Defensive Armament 6x 13x64mm Type 2 machine guns

2x 20×101mm Type 99 Mk.2 cannons
Ordnance / Bomb Load 1,764 lb / 800 kg – Maximum

Gallery

 

Artist’s conception of the operational G7M Taizan

Sources

Dyer, E. M. (2013). Japanese secret projects: experimental aircraft of the IJA and IJN 1939-1945. Burgess Hill: Classic., Aircrafts of Imperial Japanese Navy. (n.d.). Retrieved February 06, 2018, from http://zenibo-no-milimania.world.coocan.jp/epljn.html, Images: Side Profile Views by Ed Jackson – Artbyedo.com