Lavochkin La-7

Lavochkin La-7 tel que décrit sur Wikipedia de langue anglaise. Merci

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The [Vous devez être inscrit et connecté pour voir ce lien] La-7 ([Vous devez être inscrit et connecté pour voir ce lien]: Лавочкин Ла-7) was a [Vous devez être inscrit et connecté pour voir ce lien] developed during [Vous devez être inscrit et connecté pour voir ce lien].

It was a development and refinement of the [Vous devez être inscrit et connecté pour voir ce lien], and the last in a family of aircraft that had begun with the [Vous devez être inscrit et connecté pour voir ce lien] in 1938.

It saw service with the Soviet Union from September 1944, served with the Czech Air Force through 1950, and the [Vous devez être inscrit et connecté pour voir ce lien] until at least 1954 .


Design and development

By 1943, the La-5 had become a mainstay of the [Vous devez être inscrit et connecté pour voir ce lien], yet both its head designer, [Vous devez être inscrit et connecté pour voir ce lien], as well as the engineers at the [Vous devez être inscrit et connecté pour voir ce lien] ([Vous devez être inscrit et connecté pour voir ce lien]: TsAGI), felt that it could be improved upon.

TsAGI refined earlier studies of aerodynamic improvements to the La-5 airframe in mid-1943 and modified La-5FN c/n
39210206 to evaluate the changes.

These included complete sealing of the engine cowling, rearrangement of the wing center section to accommodate the oil cooler and the relocation of the engine air intake from the top of the cowling to the bottom to improve the pilot's view.

The aircraft was evaluated between December 1943 and February 1944 and proved to have exceptional performance.

Using the same engine as the standard La-5FN c/n 39210206 had a top speed of 684 kilometers per hour (425 mph) at a height of 6,150 metres (20,177 ft), some 64 kilometers per hour (40 mph) faster than the production La-5FN.

It took 5.2 minutes to climb to 5,000 meters (16,404 ft).

It was faster at low to medium altitudes than the La-5 that used the more powerful prototype [Vous devez être inscrit et connecté pour voir ce lien] engine.

Lavochkin had been monitoring TsAGI's improvements and began construction in January 1944 of an improved version of the La-5 that incorporated them as well as lighter, but stronger, metal wing [Vous devez être inscrit et connecté pour voir ce lien] to save weight.

The La-5, as well as its predecessors, had been built mostly of wood to conserve strategic materials such as aircraft alloys.

With Soviet strategists now confident that supplies of these alloys were unlikely to become a problem, Lavochkin was now able to replace some wooden parts with alloy components.

In addition Lavochkin made a number of other changes that differed from c/n 39210206.

The engine air intake was moved from the bottom of the engine cowling to the [Vous devez être inscrit et connecté pour voir ce lien], the wing/fuselage [Vous devez être inscrit et connecté pour voir ce lien]
were streamlined, each engine cylinder was provided with its own exhaust pipe, the engine cowling covers were reduced in number, a rollbar was added to the cockpit, longer shock struts were fitted for the main landing gear while that for the tail wheel was shortened, an improved PB-1B(V) gunsight was installed, and a new VISh-105V-4 propeller with a [Vous devez être inscrit et connecté pour voir ce lien]-resistant [Vous devez être inscrit et connecté pour voir ce lien] was fitted.

Three prototype 20 mm (0.79 in) [Vous devez être inscrit et connecté pour voir ce lien] armed the 1944 standard-setter ([Vous devez être inscrit et connecté pour voir ce lien]: etalon), as the modified aircraft was designated.


The etalon only made nine test-flights in February and March 1944 before testing had to be suspended after two engine failures, but quickly proved itself to be the near-equal of c/n 39210206.

It was 180 kilograms (397 lb) lighter than the earlier aircraft, which allowed the etalon to outclimb the other aircraft (4.45 minutes against 5.2 minutes climb to 5,000 meters).

However it was 33 kilometres per hour (20.5 mph) slower at sea-level, but only 4 kilometers per hour (2.5 mph) slower at 6,000 meters (19,685 ft).

The flight-tests validated Lavochkin's modifications and it was ordered into production under the designation of La-7, although the B-20 cannon were not yet ready for production and the production La-7 retained the two 20-mm [Vous devez être inscrit et connecté pour voir ce lien] armament of the La-5.

Five La-7s were built in March by Factory ([Vous devez être inscrit et connecté pour voir ce lien]: Zavod) [Vous devez être inscrit et connecté pour voir ce lien] in [Vous devez être inscrit et connecté pour voir ce lien] and three of these were accepted by the Air Force that same month.

The Moscow factory was the fastest to complete transition over to La-7 production and the last La-5FN was built there in May 1944.

Zavod Nr. 21 in [Vous devez être inscrit et connecté pour voir ce lien] was considerably slower to make the change as it did not exhaust its stock of wooden La-5 wings until October.

The quality of the early production aircraft was significantly less than the etalon due to issues with the engine, incomplete sealing of the cowling and fuselage, and defective propellers.

One such aircraft was tested, after these problems had been fixed, by the Flight Research Institute ([Vous devez être inscrit et connecté pour voir ce lien]: Lyotno-Issledovatel'skiy Institut) and proved to be only 6 kilometers per hour (3.7 mph) slower than the etalon at altitude.

Aircraft from both factories were evaluated in September by the Air Force Scientific Test Institute ([Vous devez être inscrit et connecté pour voir ce lien]: NII VVS)
and the problems persisted as the aircraft could only reach 658 kilometers per hour (409 mph) at a height of 5,900 meters (19,357 ft) and had a time to altitude of 5.1 minutes to 5,000 meters.

Combat trials began in mid-September 1944 and were generally very positive.

However four aircraft were lost to engine failures and the engines suffered from numerous lesser problems, despite its satisfactory service in the La-5FN.

One cause was the lower position of the engine air intakes in the wing roots of the La-7 which caused the engine to
ingest sand and dust.

One batch of flawed wings was built and caused six accidents, four of them fatal, in October which caused the fighter to
be grounded until the cause was determined to be a defect in the wing spar.

Production of the first aircraft fitted with three B-20 cannon began in January 1945 when 74 were delivered.

These aircraft were 65 kilograms (140 lb) heavier than those aircraft with the two ShVAK guns, but the level speed was slightly improved over the original aircraft.

However, the time to climb to 5000 meters increased by two-tenths of a second over the older model.

More than 2000 aircraft were delivered before the war's end, most by Zavod Nr. 21.

A total of 5753 aircraft had been built by Zavod Nr. 21, Nr. 381, and Nr. 99 in [Vous devez être inscrit et connecté pour voir ce lien], when production ended in early 1946.

Operational history


The 63rd Guard Fighter Aviation Corps began combat trials of the La-7 in mid-September 1944 in support of the [Vous devez être inscrit et connecté pour voir ce lien].

Thirty aircraft were provided for the trials, which lasted one month. During this time the new fighters made 462 individual [Vous devez être inscrit et connecté pour voir ce lien] and claimed 55 aerial victories while losing four aircraft in combat.

Four other La-7s were lost to non-combat causes, mostly related to engine problems.

A total of three pilots were killed during the trials to all causes.

One regimental commander, Colonel Ye. Gorbatyuk, a [Vous devez être inscrit et connecté pour voir ce lien], commented:

" The La-7 exhibited unquestionable advantages over German aircraft in multiple air combats. In addition to fighter tasks, photo reconnaissance and bombing were undertaken with success.

The aircraft surpasses the La-5FN in speed, manoeuverability, and, especially, in the landing characteristics.

It requires changes in its armament, and urgent fixing of its engine."


The twin ShVAK armament inherited from the La-5 was no longer powerful enough to bring down later, more heavily armored German fighters, especially the [Vous devez être inscrit et connecté pour voir ce lien], in a single burst, even when Soviet pilots opened fire at ranges of only 50–100 meters (160–330 ft).

The 156th Fighter Air Corps of the [Vous devez être inscrit et connecté pour voir ce lien] was the next unit to receive the La-7 in October 1944.

At one point during the month, they had fourteen aircraft simultaneously unserviceable with engine failures.

By 1 January 1945 there were 398 La-7s in front-line service of which 107 were unserviceable.

By 9 May 1945 this had increased to 967 aircraft, of which only 169 were unserviceable. For the [Vous devez être inscrit et connecté pour voir ce lien] 313 La-7s were assigned and only 28 of these were unserviceable on 9 August 1945.

The La-7 was flown by the top Soviet ace of the war, [Vous devez être inscrit et connecté pour voir ce lien].

The Ukrainian-born Kozhedub, nicknamed "Ivan the Terrible", a three-time [Vous devez être inscrit et connecté pour voir ce lien], scored his last 17 air victories in 1945 in the La-7 numbered 27, which is now preserved in the [Vous devez être inscrit et connecté pour voir ce lien] at [Vous devez être inscrit et connecté pour voir ce lien] on the outskirts of Moscow.

The last German aircraft that he shot down was the [Vous devez être inscrit et connecté pour voir ce lien], of Sergeant ([Vous devez être inscrit et connecté pour voir ce lien]: Unteroffizier) Kurt Lange from 1./KG(J)54, over [Vous devez être inscrit et connecté pour voir ce lien] on 15 February 1945.

One fighter regiment of the 1st Czech Composite Aviation Division was equipped with the La-7 and participated in the [Vous devez être inscrit et connecté pour voir ce lien] of August–October 1944.

It remained in service with the Czechs until 1950 and was designated postwar by them as the S-97.

One of these aircraft survives in the [Vous devez être inscrit et connecté pour voir ce lien].

Two La-7s from the [Vous devez être inscrit et connecté pour voir ce lien] on 23 July 1954.

Production of the La-7 amounted to 5,753 aircraft, plus 584 La-7UTI [Vous devez être inscrit et connecté pour voir ce lien].

Those aircraft still in service after the end of the war were given the [Vous devez être inscrit et connecté pour voir ce lien] Fin.

The follow-up model, the [Vous devez être inscrit et connecté pour voir ce lien], despite its outward similarity, was a completely new design.[Vous devez être inscrit et connecté pour voir ce lien]