IAR 80


The IAR 80 was a Romanian World War II low-wing monoplane, all-metal monocoque fighter and ground-attack aircraft. When it first flew, in 1939, it was comparable to contemporary designs being deployed by the airforces of the most advanced military powers such as the Hawker Hurricane and Bf 109E. Production problems and lack of available armament delayed entry of the IAR 80 into service until 1941. It remained in frontline use until the end of the war.

Development

In order to ensure that the Royal Romanian Air Force could continue to be supplied with aircraft in time of war, the government subsidized the creation of three major aircraft manufacturers in the 1920s and 1930s. The first was Societatea Pentru Exploatări Tehnice which was formed in Bucharest in 1923. Next came Industria Aeronautică Română which set up shop in Brașov in 1925. Finally there was Întreprinderea de Construcții Aeronautice Românești, which was founded in Bucharest in 1932.
In 1930 the Romanian government issued specifications for a new fighter. Although the government was not anticipating bids from its own aircraft industry, IAR produced several prototypes in response to the tender.
The contract was eventually won by the Polish PZL P.11. The ARR purchased 50 of a modified version called the P.11b, all of which were delivered in 1934. A second contest was also fought between the newer IAR 14 and PZL P.24 designs, and once again the PZL design won a contract for another 50 aircraft.
Although IAR's own designs had not entered production, they nevertheless won the contracts to build PZL fighters and Gnome-Rhône 14K engines under license. As a result of these and other licence contracts the company had enough money to fund a design studio even if its designs never went into production.
Despite losing to PZL, an IAR design team led by Ion Grosu continued work on fighter designs. He was convinced that the low-wing design of the IAR 24 represented a better design than the PZL gull-wing design, which was often referred to as the "Polish wing". Once again the team studied the new PZL fighter looking to incorporate its best features into a new aircraft, and the result was the IAR 80.

Design

  • Description: Low-wing monoplane fighter with conventional control surface layout.
  • Fuselage: The fuselage was circular in cross-section, turning to egg-shaped behind the cockpit where it incorporated a ridge-back. The rear fuselage layout, and the engine cowling were based on the Polish PZL P.24.
  • Wings: The wings were tapered with rounded tips, the trailing edge angled very slightly forwards. Small flaps ran from the fuselage to a point about 1/3 along the span, where the ailerons started and extended out to the rounded wingtips.
  • Other details: A bubble canopy was fitted, sliding to the rear to open, providing excellent visibility except over the nose due to its rearward position. A conventional tailwheel landing gear was used, with the main gear wide-set and retracting inward, with a non-retractable tail skid.
The semi-monocoque tail was copied directly from the PZL P.24. The fuselage from the engine back to the cockpit was new, consisting of a welded steel tube frame covered with duralumin sheeting. The wings were mounted low and were of the same design as those used on the early IAR 24, which had competed with the PZL P.24.
According to an urban legend, the wing profile was copied from the Italian Savoia-Marchetti SM.79 bomber, in service with the ARR at the time, as the design team lacked the time for wing section studies. As a result, the profile was less favorable for higher speeds, but gave the aircraft more maneuverability. This is false as the contract for the SM.79B licence was signed on October 1, 1938, roughly one year after the I.A.R. 80 prototype was completed.
The cockpit's interior, instruments, and gunsight were imported from foreign suppliers. This effort to aggregate a fighter from various sources was a result of the last-minute demands for a frontline fighter. The initial IAR 80s were fitted with iron sights. Starting with the 21st aircraft, these were replaced by Goerz GM2 reflector sights which were manufactured under license by Întreprinderea Optică Română as the "Telereflex" gunsights.
A Luftwaffe major who tested it in March 1941 had this to say about the IAR 80:

Prototypes

Work began on the IAR 80 prototype in late 1937, originally with an open cockpit and the IAR K14 IIIc32 engine which was a licensed Gnome-Rhône 14K II Mistral Major. The prototype was completed slowly, and first took to the air in April 1939. Test flights of the prototype were impressive; the aircraft could reach at, service ceiling of with the ability to climb to in 6 minutes, which was respectable at the time, though not up to the contemporary Supermarine Spitfire or Messerschmitt Bf 109 fighters. In comparison the PZL P.24E was almost 450 kg lighter, yet over 80 km/h slower with the same engine. The IAR 80 also proved to be enjoyable to fly and was maneuverable.
A number of minor problems turned up during the prototype phase, and were dealt with over the next year. To improve power the design was updated to mount the newer IAR K14 IIIc36. However this engine was slightly heavier than the IIIc32, which required the rear fuselage to be stretched to move the center of gravity back into the proper position. The extra space in the fuselage allowed the fuel tanks to be increased in volume to. The wing was also enlarged and the tail was revised to eliminate the bracing struts.
A side effect of this extreme rearward position was that the pilot had even worse forward visibility while taxiing than most other taildraggers. To address this somewhat, the pilot's seat was raised slightly and a bubble canopy was added.
The updated prototype was tested competitively against the Heinkel He 112, which had arrived in Romania as the start of a potentially large order. Although the He 112 was more heavily armed with two machine guns and two 20 mm cannon, the IAR 80 proved to be a better design and the ARR ordered 100 IAR 80s in December 1939 while only 30 He 112s were accepted. The government in Bucharest ordered another 100 IAR 80s in August 1940. Further orders for batches of 50 IAR 80s followed on 5 September 1941 and 11 April 1942, then another 100 on 28 May 1942, to be followed by 35 of the IAR 81C development in February 1943, with a further 15 in January 1944.

IAR 80

Production of the IAR 80 started immediately, although the armament proved to be a serious problem. The prototype had mounted only two Belgian-made Fabrique Nationale 7.92 mm machine guns, a licensed modification of the Browning.30 cal. This armament was not heavy enough against modern aircraft, and the production model was expected to mount six. The German invasion of Belgium in 1940 suspended the supply from FN, and there was no suitable replacement. The first aircraft began production in January 1940, and by 10 July the first IAR 80 took flight, followed by the 2nd on 19 July. The first five aircraft were ready to be delivered in November, with the first batch of 20 being delivered by the middle of February 1941. By April, all 50 initially ordered IAR 80s were delivered. The armament supply remained inadequate so production models only carried four guns.
The initial batch of fighters was well received by the Romanian pilots, but they found the aircraft underpowered and lacking firepower. In order to address this, the aircraft mounted the IAR K14 IVc32 engine in the 21st through 50th examples, but the firepower concern could not be resolved at the time.

IAR 80A

By April 1941 Romania was firmly in the German sphere of influence, and as a result the Germans released more FN guns for its use. These were quickly installed, and the resulting 80A model finally mounted the original complement of six guns. Armored glass in the windscreen, seat-back armor, and a new gun sight were also added at the same time, along with the newer IAR K14 IVc32 1000A engine. The extra engine power proved to be more than the fuselage structure was designed to handle, and it had to be reinforced with a duralumin "belt" just behind the cockpit in the first 95 A series aircraft built before the fuselage could be modified.
Although the IAR 80A had a more powerful engine, the added weight of the guns, ammunition and armor plating reduced the top speed slightly to. Nevertheless the new model was clearly an advancement, and the A model replaced the earlier one on the assembly line starting with the 51st airframe. Eight of these had been completed in time for the invasion of the Soviet Union on 22 June 1941.
FN guns remained in short supply, so throughout late 1941 and early 1942, guns were stripped from PZLs and observation aircraft for use in the IAR 80s.

IAR 80B

Combat over the Soviet Union proved that even six of the FN guns still lacked punch, and once again firepower was increased, with 13.2 mm FN machine guns taken from Romanian SM.79s were installed in the IAR 80 in a new lengthened wing. The result was the IAR 80B, which also introduced new radios, an area where the aircraft had previously been weak.
A total of 55 of the new design were completed, including 20 airframes which were originally intended to be IAR 81As. These last 20 were thus able to carry a bomb or a drop tank under each wing. The entire series were delivered between June and September 1942.

IAR 81A

As the fighter model was converting from the A to B series with the addition of the 13.2 mm guns, likewise the 81 model was upgraded in the same fashion, creating the IAR 81A. The only distinguishing feature between the 80B and the 81A was the 81's centerline bomb rack, and both were built on the same assembly line. The first order for 81As was cancelled and the airframes were instead delivered to fighter units as 80Bs. Efforts to obtain the Ju 87 dragged on, so a second batch of IAR 81As was ordered in May 1943 to replace losses. Once again fate intervened, and the Germans released the Ju 87 for delivery before the batch could be completed. Like the first batch, these 10 airframes were delivered as fighters.