Impressive Czech Messerschmitt Me 262 A1 Avia S-92

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In the summer of 2023, I visited the Czech Aviation Museum in Praha-Kleby for a second time. In this fascinating museum, there are a few nuggets that really interest me, such as the Avia S-199 (the Czech Messerschmitt Bf 109) and a beautiful Me 262 that I present in this article.

Messerschmitt Me 262s in the Protectorate of Bohemia-Moravia

Before and during the war, the Protectorate of Bohemia-Moravia had a very large industrial and technological fabric. The Germans benefited greatly from this, since armoured vehicles, such as the famous Hetzer, and cannons were assembled here, as were aircraft, since Junkers and BMW jet engines were manufactured here, as were complete aircraft such as the Messerschmitt Bf 109, Messerschmitt Me 262 ‘Schwalbe’ and Arado Ar 234.

1945. Me 262 A-1a of the EJ2 went into combat in the last months of the war.

There were many factories scattered around the country, some of them real factories, often car factories like Skoda's, others improvised, particularly from 1944 onwards. They could occupy a railway tunnel, a disused warehouse, and so on. It was a real jigsaw puzzle that had to be put together until the final assembly, but fortunately a railway line was often not far away.

By way of example, I was interested in the Dvůr Koroseky assembly plant. 

Dvůr Koroseky's Me 262 assembly plant 

Following the increasingly frequent massive bombardments of the protectorate and also of Germany, Albert Speer had decided to create several dozen factory-workshops scattered across what is now the Czech Republic, they had to be relatively far from the big cities to avoid their destruction. The Dvůr Koroseky factory was no exception to the rule, as it was located far from Praha. Construction of the buildings began in the spring of 1944 and was completed by the summer. The factory, designed for the final assembly of the aircraft (Einflug), covered an area of 2,000 square meters and employed no fewer than 120 workers.

The Cerny Dub railway line where parts for the Me 262 were unloaded at the Dvůr Koroseky assembly plant. In the background on the right, the station platform.

The small station at Cerny Dub where the Me 262 parts are unloaded.

In November 1944, an Me 262 landed at the Plana-Ceske Budejovice airfield. It was used to train future fitters, while other workers were also sent to the Regensburg factory in Germany.

The logistics put in place by Albert Speer's department to assemble the aircraft were impressive. The fuselages and engines were transported by train and stored in warehouses in Černý Dub, a small town just 900 metres from the factory. At night, the parts were transported to the factory where assembly of the aircraft could begin. Finally assembled, the Me 262s were loaded onto truck trailers and driven to the nearest airfield, Plana-Ceske Budejovice. After a few tests, the Messerschmitt flew off to join their future units, the JG 7, the KG(J)6 and finally the Jagverband 44.

Initial production was set at 150 Messerschmitt Me 262s per month, an optimistic rate that would never be reached. In reality, 3 Me 262s could be assembled daily, but the average was only 13 per month. A total of 40 Me 262s left the factory, a far cry from the Speer organisation's forecasts. 

The factory where the Messerschmitt Me 262s were assembled at Dvur Koroseky is now a pheasant and duck farm.

The first aircraft, Me 262 A-1a, did not leave the factory until January 1945, but production came to a sudden halt in March after a massive bombing raid on Ceske Budejovice. At that point, the supply chain was broken, and the aircraft lacked essential parts such as nuts and bolts. It was then a matter of assembling what could still be assembled from the remaining stock, and in mid-April 1945, the last Me 262 took off from the airfield.

The Germans left Ceske Budejovice on 4 May 1945 with the last aircraft fit to fly; the other aircraft (Fieseler, Bf 109, Fw 190) left at the edge of the runway were scuttled anyway, as the tanks had run dry.

Three days later, on 7 May, it was the turn of the staff at the Dvůr Koroseky factory to leave. They left behind 43 engines, 53 fuselages and 14 wings, as well as aircraft being assembled.

After the surrender, the inhabitants did not hesitate to come and help themselves in the factory, machines, drills, riveting machines disappeared.

In July 1945, the Red Army, or rather the NKVD, requisitioned the factory to the detriment of the Czechs and recovered most of the equipment, including the wooden shelves and, above all, the new engines still in the crate. Curiously, they left behind four unfinished Me 262s, which were soon to become Avia S-92s.

A little story

Remember that spare parts were unloaded at Cerny Dub. In 2011, in one of the fields bordering the village, a farmer accidentally uncovered an underground shelter dating back to the Second World War. After inspecting the site, he discovered wing and fuselage parts and, above all, three Me 262 engines ! 

Setting up the Avia S-92 project

As soon as the war was over in May 1945, the Czechoslovak air force, which was using Russian, American and British piston aircraft, wanted to add jet aircraft to its arsenal. To this end, the Czechs began negotiations with the United Kingdom to buy Gloster Meteors, but finances were tight and the deal could not be done.

For the Czechs, there was only one solution left: to take over the German technology abandoned on their territory.

In June 1945, they decided to make an inventory of the aircraft still in the country, to collect the parts needed for their assembly and maintenance and to gather all the available documentation. But the Red Army and the Americans were also on the hunt for this German technology, and the Czechs recovered only the crumbs of the spoils left on their territory. Of the 63 Me 262s fit to fly, the Czechs recovered only one, at Ruzyne, and even then it was not fully fit to fly - it was missing its engines!

Dvůr Koroseky's four unfinished models are loaded onto trucks and set off for Praha. The rest, 13 aircraft, came from the Zatec airfield where the JG 7 was based, aircraft immobilised because damaged. In the abandoned factories, 18 intact airframes were found, along with many spare parts. Engine plans were recovered from Junkers Flugzeug- und Motorenwerke Prag and the factories at Křivoklát, Loděnice and Zittwerke A.G. Betrieb Semil (Semily), which produced a large quantity of mechanical parts. This factory assembled the Jumo 004 jet engines, as well as the Jumo 205, 211 and 213. Production lines at Leichtbau GmbH and Flugzeugwerke Eger GmbH were completely dismantled and moved to the Avia-Letňany plant. 

At the end of the war, an Me 262 is found being assembled in the Dvůr Koroseky factory. The assembled Messerschmitt would become an Avia S-92.

 In autumn 1945, all the parts and incomplete aircraft were assembled at Avia: 17 Me 262s and one two-seater, the Me 262 B-1a. With the 18 airframes, the Czechs were able to assemble 31 Me 262s.

Assembly was then entrusted to the Avia-Letňany factory, which was already producing parts for the jet. The engines, fortunately quite numerous, were assembled at ČKD - Malešice. One problem remained, however: the Czechoslovak engineers were not really familiar with the Messerschmitt. 

German Me 262s become Czechoslovakian

At the end of December 1945, the first three aircraft were finally assembled and towed by lorry to Zatec airfield. The three Me 262s included one from Ruzine, another from Dvůr Koroseky and the two-seater Me 262B-1a. They were not yet ready to fly, as the Jumo 004 B1 engines, renamed M-04, were not yet ready. In March 1946, they were still being tested on the test benches at the Malešice factory.

Me 262 with the Czechoslovak flag

On 23 May, the engines were delivered to Zatec and immediately fitted to the airframes of the three Me 262s. At the same time, the technical staff were trained in maintenance, while twelve pilots were selected to fly the Messerschmitt, but before that they naturally had to be trained.

Factory pilot Bohuslav Lengál made the first ground runs of the Me 262.1 on the airfield runway. To help him in his task, he was advised by Oberleutnant Gustav Sturm, a German with 22 victories, including 5 with his Me 262 when he was with JG 7. Wounded in the final weeks of the war, the Czechs rescued him from a Red Army labour camp, so the ex-pilot's living conditions must have been more enviable. 

Oberleutnant Gustav Sturm

 The first flight of the Me 262.1 took place on 27 June 1946, one year after the start of the project. During this test flight, a landing gear problem occurred, and the hydraulic pump dependent on the left engine failed. The aircraft suffered some damage on landing, but after a few repairs, it was able to resume its test flights in July. Meanwhile, three other aircraft left the factory for validation tests.

On 5 September, factory pilot Antonin Kraus took off from Zatec, but the Me 262.1 suffered a left engine failure near Chomutov. Kraus had only one choice, to make an emergency landing in a field. The manoeuvre was tricky and failed, the aircraft was almost destroyed, but fortunately the central airframe survived and Kraus miraculously escaped.

With these landing gear problems, the engineers decided to fit a second hydraulic pump to the Me 262.

Me 262-1 becomes Avia S-92

A second aircraft, the Me 262.2, made its maiden flight on 24 October 1946. It again suffered an engine problem in flight and had to make an emergency landing on the runway, this time with no damage apart from the brakes on fire.

The Me 262/Avia S-92 PL 01, ‘PL’ designates the 6th fighter squadron. It was the second aircraft assembled, and in the early 1950s it was transferred to the Olomouc anti-aircraft school.

 From the eighth model onwards, the Me 262.8, the aircraft were delivered with their weapons, four MK-108 guns from the Vsetin weapons factory. Four aircraft were used for combat training, but on 28 November 1946 one of them crashed and the pilot was killed.

In January 1947, the last six Me 262s were completed. This brought total production to 17 single-seater aircraft. The first examples, which were used for training, were armed so that they could join a fighter squadron, while the two-seater versions were reserved for pilot training.

A new order was placed by the Czechoslovak government; this time production was to produce twenty new aircraft, including two-seater versions, but the order was only partially met.

In April, fighter squadrons 5 and 6 had ten and nine Me 262s respectively.

In June 1947, the Me 262 took the official name of Avia S-92 and CS-92 for the two-seater version.

Production of the Czech Me 262s came to a definitive halt with the delivery of four CS-92s in January 1948. But Avia did not stand still, and its engineers sought to modernise the aircraft, in particular by making the engines more reliable with new injectors and semi-automatic controls.

In the spring of 1948, the engineers attempted an unlikely graft, installing BMW 003 engines in the airframes of the S-92 and CS-92. The Czechs were well acquainted with BMW engines, since during the war they had been assembled in Brno by Klöckner-Deutz, as well as at Nachod and Svitavy. These engines were used in the much lighter Heinkel He 162 ‘Spatz’, among others. The results were bitter: the engines were singularly lacking in power and the attempt was quickly abandoned.

On 1 January 1949, fighter squadrons 5 and 6 were disbanded. The aircraft's armament was dismantled and the S-92s were used only to train pilots in jet flight. In October 1950, the first S-92s were withdrawn from service. The last of them made their final farewell flights during a military parade in Prague on 6 May 1951.

In the summer of 1951, the CS-92 two-seaters also retired, thus ending the history of the Messerschmitt Me 262 produced by the Czechs.

The Avia S-92 in the museum

Entrance to the Prague-Kleby Aviation Museum

The Avia S-92 V-34 was the fourth aircraft produced. It left the Avia workshops in 1946. In 1951, the Avia S-92 V-34 was donated to the regional technical museum. In 1979, it was transferred to the Prague Aviation Museum and, despite being in fairly good condition, was restored in 1987. It was painted in the colours of the Czechoslovak army, i.e. RLM-02 green with Czechoslovak cockades, and the inside of the engines was red. 

In 2003, the exhibition of Me 262/S-92 at the museum simply did not live up to its rarity.

I had the pleasure of seeing it in the early 2000s. Compared to its historical value, there are only 11 Me 262 left in the world, and the aircraft was badly displayed, making it difficult to take good photos. In 2009, it was moved to another hall where it could finally ‘breathe’. The photos below were taken in 2023.

The aircraft is made up of parts found in the Czech Republic, mainly from the Dvůr Koroseky factory.

From this angle, with its aerodynamic lines, the Me 262 looks like a shark.

The letter ‘V’ indicates that the aircraft was in a training squadron.

The aircraft, which was previously armed with its 4 MK-108 cannons, was decommissioned at the end of its career when it was only used for pilot training. The holes are therefore blocked by these small oval plates.

Unlike the Avia S-199, the canopy of the Czech Me 262 is identical to the German version, since all the parts are original. Note the 90mm armour plating on the front window.

Behind the canopy, we can see the small FuG 25a circular antenna.

The landing gear caused a few problems during the first test flights.

For safety reasons, the landing gear hydraulic system has two hydraulic pumps, compared with just one on the German Me 262. Note the undercarriage fairings when retracted.

Detail of the nosewheel on the cast landing gear

The undercarriage is large enough to operate on sketchy runways, as was the case at the end of the war.

The hole for the camera

A Jumo 004 renamed M-04 is on display next to the Avia S-92.

The Jumo 004 engine from another angle. As the war drew to a close and iron was in short supply, the quality of the components was inferior to that of British jet engines.

Details of the left flap mechanism, note also the screws along the wing.

In this photo we can clearly see the Staurohr positioned on a single wing and the position light.

The letter ‘V’ indicates that the aircraft was in a training squadron.

The Me 262s in the USSR

Earlier in the article I mentioned the Soviet raid on Me 262 documents and parts recovered from factories and airfields in Moravia and Germany. Let me now turn to the subject of the Soviet Me 262s.

When the Red Army penetrated the borders of the Reich, the Soviets began to get their hands on incomplete or damaged Jumo-004 engines. The Me 262 engines were crated and shipped to the Central Aircraft Engine Institute (TsIAM) for study in early March 1945.

Me 262 of l'Oberfeldwebel Helmut Lennartz JG 7

Also in March 1945, Oberbeldwebel Helmut Lennartz of III/JG 7, at the controls of his Me 262 WrN 110 426, had to make an emergency landing after the left engine failed. To add to the pilot's misfortune, the landing gear refused to extend, probably because of a hydraulic failure caused by the problem with the left engine. The Oberfeldwebel landed on its belly, but in territory occupied by the Soviets, who were delighted to get their hands on an aircraft of this type for the first time. Despite its engines being slightly damaged during the landing, the aircraft was quickly dismantled and transported to the Air Force Research Institute at Chkalovskaya, near Moscow, where it arrived on 30 March. After the surrender, the Soviets seized around twenty Me 262s, but only three were damaged and headed for Moscow.

It was the end of the war, the surrender. German engineers were taken prisoner and during their interrogations, the Soviets realised that the technical documents were kept in the Wiener Neustadt, Bergkristall and, as we read earlier, Ceske Budejovice factories. This explains the raid on all the equipment at the Dvůr Koroseky factory to the detriment of the Czechs.

In the summer of 1945, the Soviet engineers had everything they needed to work: one aeroplane in flying condition, three others incomplete. Engines, technical documents, machine tools and German technicians....

JG 7's ex-Me 262 was used for flight testing, while a wooden model was built and tested in the wind tunnel to study the aircraft's aerodynamics.

In August 1946, a second aircraft was finally ready to fly, while a third was transformed into a two-seater version at factory N°481 in Syzran. The fourth, an Me 262C, was only used for resistance tests and to test the Jumo 004 and BMW 003E1 engines.

End of the Me 262 of JG 7

On 15 August 1946, test pilot Kotchetkov took the controls of the 110 426 for the first time. The pilot noted that the aircraft was faster than any piston aircraft, whether Soviet or Western. Both its range and rate of climb were satisfactory. Overall, the aircraft is easy to control. The only problem was take-off thrust: the Me 262 required a 3-kilometers runway if it was not equipped with boosters !

On 17 September 1946, one of the 110 426's engines failed during take-off and the plane crashed, killing the pilot.

the Me 262 project is over

To speed up the development of the aircraft, the Soviets decided to manufacture other aircraft in factories n°381 in Moscow and n°292 in Saratov. These were mass-produced aircraft from A to Z, improved by the engineers and, above all, lightened by 580 kg. Later, it was planned to fit RD-10 engines (Jumo made in the USSR). But this remained a project, and despite Stalin's injunctions, the Soviet Me 262 never saw the light of day. Thanks to the German engineers who arrived in the Soviet Union in October 1946 (just over 2,000 in all), aeronautical technology took a quantum leap forward with the Lavochkine, Mig 15 and Yak 23.

The Yak 17

A Yak 17 is on display in the Kleby museum. The special feature of this aircraft is that it is powered by a Jumo 004 engine, the same as the Me 262 and Avia S-92.

The Soviets had got their hands on the engines, but they needed German engineers to reproduce them at Factory 26 in Ufa under the name RD-10A. The Jumo/RD 10A was first fitted to the Yak 15, which made its maiden flight on 24 April 1946. 

The Yak 17 launched in 1947 was the result of Soviet research into the Me 262.

The Yak 17 is powered by an RD-10 engine that is nothing less than a Soviet-made Jumo-004.

 

Links 

 

BMW 801 engine of Fw 190

Avia Cs 199/ Messerschmitt Bf 09, the czech airplane

Avia S199 Vs Messeschmitt Bf 109

Heinkel He 162A2