Report on La-5 by Hans-Werner Lerche, Erprobungsstelle Rechlin

[ZachariasX]

Hi guys

 

I just came across Hans-Werner Lerche's book "Testpilot auf Beuteflugzeugen" (ISBN 3-87943-495-6) and I think it's one of the rarer books. I'm affraid slightly less interessting than it could be, but still a good find.

 

In this book, the author (and testpilot of more than 100 different types of aircraft (German, English, Russian, American, Italian...) for the Erprobungsstelle Rechlin, included a memorandum assessing the flying qualities of the La-5. It is also the only detailed description of flight characteristics in the book and included as a tiny, semi legible reprint of the original memorandum:

 

 

 

 

 

In short (for non-german speakers), he is impressed by the planes performance below 3 km altitude, although he considers it slower than either 109 or 190 (he doesn't specify which types, calling them 8-109 and 8-190 in this report) at all altitudes, best climb at low altitudes between the 109 and the 190 and thus a very strong opponent for the 190 in climbing and turning. But he is not impressed by the endurance of only 40 mins.

 

In the book, he reacalls how rough the engine ran and that he used to stick cotton plugs in his ears, something he otherwhise never had to do to cancel the exessive noise a bit more.

 

He recommends fast, shallow dives and climbs to keep energy and distance, especially in case for the 190 and to avoid dogfights ("Kurbeleien"). He specifically mentiones the Thunderbolt and the way it is flown as a startegy to make best use of the 190 vs. the La-5.

 

 

This just to add some material. I never saw this nowhere. Hope you enjoy it.

 

 

Z

[SYN_Vorlander]

Thx for the info.

[Finkeren]

Doesn't sound too far from what we have in BoS. The speed seems less impressive than what the La-5 in BoS is capable of on the deck, but that could be attributed to him testing a captured aircraft propably in less than mint condition.

[6./ZG26_5tuka]

Doesn't sound too far from what we have in BoS. The speed seems less impressive than what the La-5 in BoS is capable of on the deck, but that could be attributed to him testing a captured aircraft propably in less than mint condition.

He wrote sth about it's condition, which was "good". It had "smooth surfaces" and the "slats fit in properly". According to him the machine was in tecnicly "flawless condition", although he couldn't tell how many work hours it got already (he only states it had been flown for a long time already).

 

Also interesting note: "The engine must not be driven at emergency power if supercharger is engaged" with "Emergency power" standing for 2500RPM / 1,605" power setting. That sure does not account to the early La-5 we have ingame though that can only be driven at what he reffers to as "Nominal Power" (2400RPM / 1,36" ).

[ZachariasX]

Doesn't sound too far from what we have in BoS. The speed seems less impressive than what the La-5 in BoS is capable of on the deck, but that could be attributed to him testing a captured aircraft propably in less than mint condition.

 

He just mentiones thet this aircraft was got in german hands in flight-ready ("flugklar") condition in Gross-Schimanen (Ostpreussen), probably due to a desoriented pilot that landed on the wrong airfield. They collected a fair number of aircraft that way on the eastern front. What it probably represented was an average La-5 in regular condition at the front.

 

He also states that in most cases russian planes were "used up" ("aufgebraucht") by the pilots flying along with the front units and they were left with not much to bring home to Rechlin. They also used to collect the fuel from prize aircraft to be able to put in the right juice. It is probably the case here. They mostly used original fuels and lubrication if avaliable, especially for the Merlin powered aircraft. Otherwise the rare high octane fuel of their own making was used especially for the British and American planes.

 

That pilots of the front units just hoped in prize aircraft was however not common on the western front. This because especially fighter planes in flyable condition were extremely rare and in the case of the first Thunderbolt (November 1943, in Caen; that guy actually landed there on the airfield) the "highly decorated fighter ace" that led author there was of course extremely keen to get a ride in it first. But at the sight of all these levers controlling the turbo etc, his heart sank and he gave it away directly.

 

The Yak 3 the author flew a bit later on he mentioned being in very good condition and he was impressed by the nice and clean plywood finishing of the wings. He really praised the aircrafts performance at low altitude. The same kind of fun he had with the Tempest V.

 

The only aircraft that really seemed to deeply impress him for their flying characteristics were the Me-262 (for obvious reasons, despite requiring a lot of "Gottvertrauen" due to it's poor accelleration at slow speeds, most notably during take-off) and the Mustang. He was thrilled what it could do "with a comparably weak engine" and praised the airframe. He also complimented the fact that could sit in it in a very comfortable way because it was roomy. Same for the Thundebolt. In the 109 he said he really had to croch down for not hitting the canopy with the head. The few Spitfires they souced were also extremely popular along with the Mustang among the German pilots who could fly them. Specifically among the "Beutezirkus Rosarius".

 

The Do-335 he flew (VG+PH, now on display at the smithonian) in a last ferry flight was unfortunately not commented on more than beeing the fastest prop plane and suffering two mechanical breakdowns on the flights from Rechlin to Oberpfaffenhofen. A fuel pump broke, then the landing gear malfuntioned requiring manual opreation.

[CBAPHOI]

He wrote sth about it's condition, which was "good". It had "smooth surfaces" and the "slats fit in properly". According to him the machine was in tecnicly "flawless condition", although he couldn't tell how many work hours it got already (he only states it had been flown for a long time already).

 

Also interesting note: "The engine must not be driven at emergency power if supercharger is engaged" with "Emergency power" standing for 2500RPM / 1,605" power setting. That sure does not account to the early La-5 we have ingame though that can only be driven at what he reffers to as "Nominal Power" (2400RPM / 1,36" ).

 

We have an article about this testing in Russian and it says there that it was LA-5FN, not LA-5.

http://www.airpages.ru/ru/la5fn_1.shtml

[ZachariasX]

We have an article about this testing in Russian and it says there that it was LA-5FN, not LA-5.

http://www.airpages.ru/ru/la5fn_1.shtml

 

Lerche says it being a La-5 with an M 82 FNW engine.

[MK_RED13]

Hehe... and now.. we want to see the documents used by the developers for BoS.. please    

[=362nd_FS=Hiromachi]

Umm, but they were posted in http://forum.il2sturmovik.com/topic/16752-il-2bos-user-manual-released-first-edition-english/

Scroll to page 52, then you will see that as a source for La-5 they used a certain flight manual. What are figures in it I dont know though. But same goes for LaGG-3, Il-2, Pe-2 and Yak-1. 

 

Maybe some forum members from Russia know where to find scans of those manuals. 

[SKG51_robtek]

Lerche says it being a La-5 with an M 82 FNW engine.

And that makes it a La-5 FN, doesn't it?

 

It's only about 500 ps difference to the La-5.

Edited June 16, 2015 by I./ZG15_robtek

[Sgt_Joch]

Lerche tested a La-5FN. The test is discussed in more detail here (pp. 66-67):

 

https://books.google.ca/books?id=X0L2axDnZCkC&pg=PA67&lpg=PA67&dq=lerche+la5fn+test&source=bl&ots=XrMfDUVgpm&sig=jOnTONnUzSFZA_otlFVW8mcqMTE&hl=en&sa=X&ved=0CC8Q6AEwAmoVChMIlt722ZeVxgIV7xqMCh1dLQBn#v=onepage&q&f=false

 

most likely a combat weary example with maybe a damaged engine as explained in the text.

 

According to my notes Soviet tests of the 1943 La-5 production model recorded a max airspeed of 518 kmh at sea level (without wep), 600 kmh at 6.5 km and a turn time of 19 seconds. It is listed as a 1943 model in the performance charts, but reached the frontline squadrons and flew combat missions beginning in november 1942 over Stalingrad.

 

The speeds matches what Celestiale recorded in his ingame tests.

[ZachariasX]

Lerche tested a La-5FN. The test is discussed in more detail here (pp. 66-67):

 

https://books.google.ca/books?id=X0L2axDnZCkC&pg=PA67&lpg=PA67&dq=lerche+la5fn+test&source=bl&ots=XrMfDUVgpm&sig=jOnTONnUzSFZA_otlFVW8mcqMTE&hl=en&sa=X&ved=0CC8Q6AEwAmoVChMIlt722ZeVxgIV7xqMCh1dLQBn#v=onepage&q&f=false

 

most likely a combat weary example with maybe a damaged engine as explained in the text.

 

According to my notes Soviet tests of the 1943 La-5 production model recorded a max airspeed of 518 kmh at sea level (without wep), 600 kmh at 6.5 km and a turn time of 19 seconds. It is listed as a 1943 model in the performance charts, but reached the frontline squadrons and flew combat missions beginning in november 1942 over Stalingrad.

 

The speeds matches what Celestiale recorded in his ingame tests.

 

I don’t get the impression that Lerche flew a “used up” plane even though Dmitriy says so. And yes, it is for sure a La-5FN, it is just that in the reports, a La-5 is a La-5, and they may vary in the engine used, but they themselves didn’t care so much for the precise semantics of the plane names back then. But yes, it seems to be a La-5FN.

 

Lerche describes the plane being in good condition (“in einwandfreiem Zustand”), but the operating time was undocumented and they saw it was being flown for “a longer time”. The surface finish was good and the slots were operating well. The oxygen system was apparently never used and fell apart when he tried to use it. This says a lot about how the flying on that front was done, especially since this aircraft had some hours already. But they still could rate the power of the engine. So it couldn’t be all that broken.

 

He notes the engine running rough and really loud, requiring additional earplugs in order not to be semi-deaf after landing. But in the light of his description of the Yak 3 (which he praised for its performance), also there he remembered the rough and noisy run of the engine. This in contrast to his descriptions of the German engines, the Merlin engine, or most notably the Double Wasp of the Thunderbolt.

 

I find the text from Dmitriy Khazanov not giving a really accurate translation of Lerches report. I copied here the passage you mentioned:

 

The La-5FN represents significant progress in both performance and operational characteristics when compared to early Soviet fighters. Its performance at altitudes up to 3,000 m [9,840 ft] warrants special attention. However, its maximum speed at any altitude is less than that of German fighters. The fighter’s best rate of climb at low Ievel compares favorably with that achieved in the Fw 190A-8 and Bf 109G. The La-5FN's rate of climb and rate of trun at 3,000m [9,840 ft] is comparable with the Fw 190A. This is because the efficiency of the fighter’s ailerons is truly outstanding. At an air speed of 450 km/h [280 mph], a roll can be performed in less than four seconds. However, at 600 km/h [375 mph] pressure on the ailerons becomes excessive. At 1000 m [3,280 ft] a maximum rate 360-degree horizontal turn can be performed in 25 seconds using engine boost. In view of the merits of its engine, the La-5FN is more suited to low altitude combat. lts maximum speed at low Ievel is comparable with that of the F- 190A-8 and Bf-109G on boost. Acceleration characteristics are balanced. The La-5FN is bettered by the Bf 109G which MW 50 both in terms of its top speed and rate of climb at any altitude. The Russian fighter is superior to the Fw 190A-8 up to 3,000 m [9,840 ft]. You should dive in order to escape an attack from a La-5FN.

 

The author makes the assumption of the Fw-190 being an A-8 and the Bf-109 being a Gustav. Lerche mentiones “8-190” and “8-109” respectively.  It is a slightly “patched together” excerpt from the report. The Russian fighter is superior to the Fw 190A-8 up to 3,000 m [9,840 ft]. This I can’t find in Lerches report. He says that the La-5 climbs better, accelerates better and requires less time for a full circle than the 8-190 below 3000 meters. But there is no general sort of superiority described. He advises against dogfights, “because Russian pilots, used to inferior flight performances, wouldn’t be impressed with the described turn characteristics of the plane” (whatever Lerche meant with that). “You should dive in order to escape an attack from a La-SFN.”  I can’t find that. He says that one should pull away slightly with high speed because the 8-190 is superior is a slight dive and higher speeds (“in allen angedrückten Flugzuständen überlegen”). He also recommends a shallow climb to get away, as the best climb of the La-5 is at slower speeds with a steeper angle.

 

Well, all this just to illustrate that it is good to have more than secondary literature. There are some great documents shared here in these forums.  Just felt like adding what I found. Haven’t tried out yet BoM extensively… still stuck with RoF

 

Z

[Sgt_Joch]

I did not mean it as a criticism. Lerche's report is very valuable, as is any first hand documents on these planes. The big issue is that the performance figures is so much lower than what the Soviets found in their own tests so it is hard to know where the discrepancy comes from.

 

I do know all Soviet planes and equipment were designed with a very short lifetime in mind and wore out quickly, partly why the Lagg-3, La-5 and Yak-1 were made largely out of wood.

 

There is an interesting anecdote about the British Valentine tank. The Soviets received many through Lend Lease and used most for training, not because it was a bad tank, but because its engine was designed to last for 100,000 kms. The Soviets thought it was a waste to use it in combat where it would be destroyed in a few weeks and so used it in training schools where its long engine life would actually be useful.

Edited June 17, 2015 by Sgt_Joch

[ZachariasX]

I did not mean it as a criticism. Lerche's report is very valuable, as is any first hand documents on these planes. The big issue is that the performance figures is so much lower than what the Soviets found in their own tests so it is hard to know where the discrepancy comes from.

 

I do know all Soviet planes and equipment were designed with a very short lifetime in mind and wore out quickly, partly why the Lagg-3, La-5 and Yak-1 were made largely out of wood.

 

There is an interesting anecdote about the British Valentine tank. The Soviets received many through Lend Lease and used most for training, not because it was a bad tank, but because its engine was designed to last for 100,000 kms. The Soviets thought it was a waste to use it in combat where it would be destroyed in a few weeks and so used it in training schools where its long engine life would actually be useful.

 

I didn't take it as critisism, I was just surprised by Dimitrys tone in the abstract of Lerches report. Apart from actual or real values/specs, I found it interessting to compare this first hand report with secondary literature that went through at least 2 rounds of translation. I really like these forums because people like you have all these sources at hand to point out. Sometimes, with having all these reports at hand one can see how certain "wisdom" about planes emerged.

 

Personally I think the planes of all makes had some variation in speed and performance, especially the Soviet ones. I've read somewhere that sometimes not even the wings of similar types of Yak planes were interchangable, "because they wouldn't fit". This may or may not be true, but I doubt that a company making a plane wouldnd't rate types that weren't built to perfection. On the other hand at the front, you probably have the whole mix of planes, some performing as if they were made for the ministery of propaganda and some, well, less. And "using up planes": even the Germans firewalled the throttle making their engine short lived because the pilots didn't want to be more short lived than necessary. The British or Amercans seemed to be more careful with their eqauipment...

 

What I really like to find in literature or reports is when advice is given on how to fly the aircraft vs. another specific type. I find this more valuable info than sheer speed or climb. But it is iteressting how much use you can make of it. for instance according to the specs, the Me-210 is not a bad plane. But you have to sit in it you'll think otherwise.

Edited June 17, 2015 by ZachariasX

[Freycinet]

Beuteflugzeugen is a very nice book, have it on my shelf, read it many years ago.

[SR-F_Winger]

All this wont have any effect on the BOS FMs anyways. So why do you even try?

[ZachariasX]

All this wont have any effect on the BOS FMs anyways. So why do you even try?

 

I was only sharing the document. This is the ONLY purpose of this thread. At least of my OP. I like original documents. Just that. 777 do what they do.

[71st_AH_Mastiff]

thanks for sharing.

[Blooddawn1942]

Yes. Interesting read. Thanks! First hand accounts are way more interesting then datasheeds. At least to me.

[Bogun]

I spent some time researching history of this La-5FN Hans-Werner Lerche tested in Rechlin in 1945.

He ferried this plane ("airworthy example", which is often incorrectly translated to Russian as in "perfect condition") from Gross-Schimanen airfield (East Prussia) to Rechlin September 15, 1944, and tested it until the mid of April, 1945 (!).

 

There are few inconsistencies about this plane:

1. Engine named as "M 82 FNW". That was a real name of the engine (М-82ФНВ) in the first part of 1943, then it was changed to M-82FN (М-82ФН), and later (April, 1944) to ASh-82FN (АШ-82ФН). Attached a plate from different Russian engine - VK-105PF (from Yak-9), but M-82FNV plate would look similar. 
2. Broken landing gear covers. I actually cannot find any other picture "airworthy" La-5FN with broken landing gear covers.
3. While flying La-5-FN Lerche got carbon-dioxide poisoning, so he made sure to fly the plane wearing oxygen mask. Well, it is well known that Russians almost never had oxygen tanks filled, I saw no pictures of Russian pilots flying wearing oxygen mask, reading Russian pilots memories I can count times when they needed those masks probably on one hand.
   This BTW, points to the damaged firewall partition between engine and pilot's compartments, or damaged pipes for filling gas tanks with cooled engine exhaust gases.

All - damaged firewall, pipes, missing landing gear covers kinda hint botched crash landing restoration. Funny, but in the Lerche's book another example of botched installation of landing gear covers on P-39 Aircobra almost killed him.

 

Russians traced 3 possible La-5FNs, one of which could be plane tested by Lerche, but all 3 crash landed sometime mid-1943, nowhere near Gross-Schimanen. So, what was happening to those planes from mid-1943 to September of 1944 when it got into Lerche's hands? 

Edited December 7, 2019 by Bogun