Romania (1934)
Training and Reconnaissance Aircraft – None Built

The establishment of I.A.R. (Industria Aeronautică Română) at Brașov in 1925 was a huge step forward for Romanian industry, and more importantly, the A.R.R. (Aeronautica Regală Română) Romania’s Royal Air Force. However, with the turn of the decade and rapid development of military aircraft around the world, Romanian aircraft factories, which also included S.E.T. (Societatea pentru Exploatări Tehnice) and the new I.C.A.R. (Întreprinderea de Construcții Aeronautice Românești), were lagging behind in terms of equipment and production facilities. This led to a variety of issues which pushed IAR into bankruptcy. The IAR H.S.300 was IAR’s last attempt at creating an aircraft for the ARR before drastic changes were made, both in terms of the plant’s management and the air force’s requirements and needs.

Development

With the deteriorating stability in 1930s Europe, Romania’s M.A.N. (Ministerul Apărării Naționale, Eng: Ministry of Defense) decided that all of its future aircraft had to be of all-metal construction. This caused a lot of issues with the national aircraft manufacturers, which simply did not have the equipment and facilities to produce all-metal aircraft. Similar issues plagued all Romanian industries even during the Second World War.

Between 1930 and 1933, IAR developed several competent fighter aircraft designs, but none were accepted into service due to their construction, which was part metal, part wood. This would force IAR into bankruptcy. Only a small order of 20 IAR-14 fighters was placed in early 1933, under clandestine conditions, directly from the Romanian high command to the factory.

Things changed, however, in 1934, when the leadership at IAR requested an investigation from the Romanian Senate. They accused the MAN of not respecting the previously signed contract, ordering 100 aircraft and 150 engines per year, and buying foreign aircraft instead. In a meeting, a MAN representative responded to the allegations with the following:

“The majority of countries on the world stage have, starting from 1930, begun to equip their own air forces with planes built entirely out of metal, offering much better performance. This also being the policy of the Ministry of Equipment of the Romanian Air Force, taking into consideration the international situation, which is deteriorating swiftly, as long as the IAR factory will continue to only build aircraft from wood or mixed wood-metal, we are not interested, and will continue to rely on imports!”

During the same period, IAR developed a handful of new aircraft, one of them being a reconnaissance, observation, and training monoplane which was proposed directly to the S.S.A. (Subsecretariatul de Stat al Aerului). The blueprints and design specifications of the aircraft were discovered by Giorge Ciocoș at the Pitești archives.

The plane was directly based on the IAR-22 trainer according to the factory documents, but a close analysis shows that it borrows details from several IAR aircraft, such as the empennage, which is borrowed from the IAR-23. Several other dimensions are the same as the IAR-23, such as the tailplane. It is entirely possible that the IAR-23, which was developed in March of 1934, served as a basis or inspiration for the IAR-H.S.300, as it was developed only 4 months later, in July 1934. Curiously, the documents continue to claim that the project was based on the IAR-22, stating that the wings are from the IAR-22, while a simple comparison of drawings or photos clearly shows that they are from the IAR-23. Additionally, the wings are identical to the IAR-21, which had undergone static testing in August of 1932.

Design & Construction

In the IAR documents, the aircraft is never officially given a name, instead titled as “IAR plane for training of reconnaissance and observation equipped with Hispano Suiza 300 hp engine.” Hence, it was given the unofficial moniker IAR-H.S. 300, referencing the engine. There are 7 documents detailing the layout and construction of the aircraft, with an additional 5 schemes and drawings showing the dimensions and design.

The IAR-H.S.300 was a rather small monoplane, with a wingspan of 12 meters, and a total length of 8.45 meters. Empty, the plane would weigh 989 kg, and 1,420 kg fully equipped with radio and other onboard equipment.

The wing would be made entirely out of spruce, consisting of the central frame, with a length of 3 meters, and the wings themselves, at 4.5 meters each. The wings would be built upon two wooden spars, and the wing shape made from plywood. The longerons were attached to the rest of the aircraft frame via duralumin 90 degree braces. The leading edge and central portion were wrapped with plywood, while the trailing edge and flaps were covered with cloth. The horizontal stabilizers were also of wooden construction and wrapped with cloth.

In terms of the frame, it was made out of 4 spruce longerons, attached to each other via diagonal wooden supports. The attaching points were out of duralumin, and fastened with rivets. The fuselage that wrapped around the body was made out of sheet metal in the front and around the engine, plywood around the center and cloth on the tail. The elevator had a duralumin frame, but was covered with cloth, while the vertical stabilizer was made entirely out of duralumin construction and wrapped with cloth.

The landing gear was conventional, consisting of two wheels with brakes and shock absorbers. It was fixed and reinforced with a diagonal truss. Total weight of the landing gear would be 65 kg.

As for fuel reserves, the aircraft would’ve had two fuel tanks, one in each wing, with a capacity of 115 liters each (230 total) but there was the possibility to increase it up to 500 liters total. The oil tank had a capacity of 18 liters.

As mentioned previously, the engine was a Hispano Suiza 8Fb, a 18,5 L V-8. It had between 312 to 320 horsepower at normal power, and a maximum of 337. Typical revolutions per minute were 1,800 rpm and max was 2,100 rpm. Total weight was 275 kg. First variants were developed in 1914 and would be one of the most used engines by the Entente Powers during the First World War, which Romania was a part of, but later variants remained widely used throughout the 1920s and 30s. This powerplant would theoretically allow the IAR to reach a top speed of 238 km/h at 2,000 meters. Max ground speed was 245 km/h. Landing speed was to be 92 km/h. Range was 750 km with the 230 liter configuration. Time to altitude of 3000 meters was 8 min and 30 seconds.

Crew and Equipment

As a typical observation and training aircraft, there were two seats in the plane, both equipped with steering controls. The pilot is seated directly above the wings, in an open cockpit. He sat low in the plane’s body, with only his head protruding, protected by a small windshield.

The second aviator sat right behind the wings, higher up than the pilot for better visibility. He sat in a rotating turret that had a machine gun equipped, what type is unspecified. Below him were three drums, with 100 rounds each (300 total). A standard A.T.R. 4 radio was also available. The photo camera was positioned behind the turret, but could be operated from within the turret. Although the turret allowed for enough space to maneuver comfortably, the crewmans parachute was placed in a shelf behind him, for more efficient mobility.

Faith

Ultimately, the S.S.A. rejected the IAR-H.S.300. While the Air Force did need new observation and training aircraft, its method of construction and materials used were not accepted by the MAN and MAM (Ministerul Aerului și Marinei). Despite this, the plane seemed to be adequate for its role and time, with modern radio and photography devices, a turret and a respectable engine. Had IAR been able to produce a prototype and offer improvements, such as a fully enclosed cockpit, it would have been a competitive aircraft in its role. Unfortunately, IAR was bankrupt and unable to promote its designs.

The salvation of IAR came in 1936, when Poland became the only supplier to grant Romania production licenses. M.A.N. purchased licenses for the production of the Polish PZL-11 and PZL-24 aircraft, which had full metal fuselages, and were decent aircraft for their time. This required vast investments into the IAR factory, for the tooling and production facilities, and also the personnel and design bureau.

However in 1938, with war knocking at Europe’s door, the M.A.N. equipped the Romanian Air Force with whatever the factories could produce, such as the IAR-37, IAR-38, and IAR-39, which likely wouldn’t have been produced if the IAR-H.S.300 had been pushed into service and upgraded, as they were also reconnaissance and light bomber aircraft. These aircraft did not prove to be a significant upgrade, and were also built out of a combination of metal and wood, but circumstances forced M.A.N. to buy them regardless.

Conclusion

The IAR-H.S.300 was a small reconnaissance and training aircraft developed as a last ditch attempt by IAR for the Romanian Air Force. However due to its construction consisting of part metal, part wood combined with the Romanian Ministry of Defence’s reluctance to accept such planes, the project died quickly. In the end, the Romanian Air Force was forced to purchase mixed construction wood-metal planes from IAR, due to the mounting hostilities of late 30s Europe.

Acronyms and Translations

• I.A.R. (Industria Aeronautică Română) Eng: Romanian Aeronautic Industry
• A.R.R. (Aeronautica Regală Română) Eng: Royal Romanian air force
• S.E.T. (Societatea pentru Exploatări Tehnice) Eng: Technical Exploitation Society
• I.C.A.R. (Întreprinderea de Construcții Aeronautice Românești) Eng: Romanian Aeronautics Construction Company
• M.A.N. (Ministerul Apărării Naționale, Eng: Ministry of Defence
• S.S.A. (Subsecretariatul de Stat al Aerului) Eng: State Subsecretary of Air
• MAM (Ministerul Aerului și Marinei) Eng: Ministry of Air and Navy

IAR H.S. 300 Specifications
Wingspans	12 m / 39 ft 4 in
Length	8.45 m / 27 ft 9 in
Wing Area	21.9 m² / 71.9 ft²
Engine	Hispano Suiza 8Fb V-8, 312 hp
Empty Weight	989 kg / 2,180 lb
Maximum Takeoff Weight	1,429 kg / 3,150 lb
Fuel Capacity	230 liters / 60.75 gal
Maximum Speed	238 kph / 147 mph
Time to Altitude	3,000 meters / 9,840 feet – 8 min 30 sec 4,000 meters / 13,120 feet – 13 min 0 sec 5,000 meters / 16,400 feet – 19 min 10 sec
Range	750 km / 466 miles
Crew	1 Pilot & 1 Radio Operator/Photographer
Armament	Single Machine Gun (Unspecified) 3x 100 Round Drum Magazines

Gallery

Credits

• Written by Pavel Alexe
• Edited by Henry H., Ed Jackson, & Stan Lucian
• Illustration by Godzilla
• Special thanks to Dan Antoniu and Eng. L. C. Tascau

Sources

• Dan Antoniu, Aviatia ilustrata, No.1 2018
• Pitesti Archives