How soon could a DB-engined FW190 entered combat?

[DonL]

Mr DonL
With the knowledge that we have today , i believe we can agree that BMW 801 was a failure
Never bacame truly reliable
Never had a good power to weight ratio despite it used C3 fuel
Never had even decent altitude performance
Needed that cooling fan behind the propelller that was consuming valuable power
Very inefficient supercharger

The resources and the c3 fuel could had been used for much better projects like Jumo 211R , additionals and faster developed DB605s

Dear Jim,

that's one of the rare issues we have to disagree.
I can't see where the BMW 801 was a failure.
It was reliable in late 1942 and offers more Steig und Kampfleistung then any other german engine at 1942.
There are certain issues about BMW you have to consider.
BMW was with Bramo the two biggest radial engine producer at germany and both came from the civilian aviation line. Siemens didn't want to enlarge Bramo at the timeline 1934/1935, so Bramo was socialized from the RLM and sold to BMW. Both companys produced their civilian line BMW 132 (P&R 1630) and Bramo 323 (Bristol Jupiter), both heavy modified from both companys, but both had relative old production lines and tools.
The fusion of Bramo and BMW happened since 1937/38, BMW new engine factory was built not until 1938 (Junkers and DB factorys were built much earlier) and through the fusion, the civilian market and the failure of the BMW 139, BMW was very late in the military engine development with the BMW 801, which was developed out of the BMW 139 and Bramo 329.
The main issues for BMW/Bramo was the tooling of the new built engine factory at 1938, because it was this late, BMW had to fight with endless other companys about good around toolings to equip their engine factory. This fighting holded on till 1943 and BMW had not as much modern allround production tools as DB and Junkers.
Anyway from a rational viewpoint it was more then clear for the RLM to fund a a new military radial engine from this two fusioned engine companys (advertisement 1935), to get the human resources (engine engineers) and production lines to work for the military development.

BMW/Bramo was compare to DB and Junkers a very small company 50000 workmen at 1944 (half of this slave laboured) and was able to develop the BMW 801 and the BMW 003 and put both in mass production.
The BMW 801 is to my opinion absolutely comparable to the Wright 2600 and very equal in performance.
The most issues of BMW/Bramo was their late change to the military development of engines, so they had major issues with production tools, human resources (engine engineers) and not the reputation of Junkers and DB and were always number 3 at the RLM, also at the attention and treatment through the RLM.

I agree. However DB603 engine offered more bang for the buck.

DB603 prototype was running two years before BMW801 prototype and if properly funded I think Daimler-Benz would have maintained at least a two year development lead over BMW801. DB603 was also less expensive to produce, allowed a hub cannon, more reliable and smaller engine diameter made for better aerodynamics, especially in fighter aircraft. It's the engine Fw-190 should have been designed for from 1937 onward rather then betting on a radial engine which didn't even have a prototype running until Fw-190 design was well advanced.

Make BMW801 engine program a low development priority (i.e. similar to historical DB603 funding after 1940). If/when BMW801 engine starts looking promising then development funding gets increased. Otherwise the BMW801 program gets axed after a few years without entering mass production.

This is simply a dream and very far from realistic!
I have tried to explain this issue more the one time, so it is my last try.
The BMW 801 has simply nothing to do with the development and funding of the DB 603, weather from the timeline nor the human resources.
The Bomber B and Bomber A advertisement with the DB 604X and the DB 606 were the issues for the DB 603.

You should explain Dave how DB should have developed a DB 601A to the DB 601E/DB605, the DB 606/610,the DB 603 and the Db 604X?
It is impossible from human resources and the development capacity! And please don't tell us you could have sourced out something to BMW, because of the BMW VI, which was a WWI design and BMW had changed at the early 30er to radial engines. It is impossible to shift mainly development recources and production capacity between such developed engine companys and it doesn't make sense also from the viewpoint of competition.

One last time, the development of the BMW 801 had nothing to do with development of the DB 603.
If you want a DB 603 at 1942/43 earliest realistic introduction time, you can't have a Bomber B advertisemnet and only a "normal" Bomber A advetisement with 4 normal engines.

 

[davebender]

I'd call that an excellent tradeoff. No DB604 engine. Full speed ahead with DB603 engine development and mass production.

 

[DonL]

I'd call that an excellent tradeoff. No DB604 engine. Full speed ahead with DB603 engine development and mass production.

No the advertisement of the Bomber B was a 2000 PS engine. So no DB 604X no Bomber B advertisement. There is no tradeoff between a DB 604X and the DB 603.
And even then DB had to develop three different engines, DB 601A to DB 601E/Db605; coupled engines 606/610 and the Db 603, you can't develop the DB 603 full speed.

As you look at every other big engine factory in the World, which could develop three engines at the same time?
Even Jumkers and Rolls Royce didn't want to develop more then two engines.
A fast developed DB 603 mass production ready 1942 suspend also the coupled engines with all it's problems and massive development time and resources
Also you should think about the issue that all major development steps came from the DB 601 till the DB 605 (pressurised water cooling, sleeve bearings, more boost etc.), all this must be developed first to the DB 601/DB 605 (because highest priority at this timeline) and later would be introduced to the DB 603, so no mass production for the DB 603 before 1942.
It is impossible and also no advertidement of the Bomber B and the Bomber A with coupled engines.

 

[davebender]

I'm under the impression DB606 engine coupling was developed by someone other then Daimler-Benz.

 

[DonL]

This is a wrong impression, all DB engines were developed from DB at Untertürkheim (development center).
Junkers helped to solve major issues of the DB 606 and DB 610 at 1943, but had nothing to do with the development.

 

[altsym]

DonL,

A little off subject but didn't III./JG 27 use the 1.98ata (2000ps) DB 605's in trials around December 1944?

 

[davebender]

Daimler-Benz developed DB601 and DB605 engines but I think someone else built the coupling which created DB606 and DB610 engines.

 

[DonL]

Dave the engine was developed from DB with all it's issues, mainly the cooling issue and the maintance issue. Also the coupling was developed to my knowledge from DB, if some sub supplyer produced the coupling or was involved in the development, I don't know. But the coupling wasn't the issue of this engine, because the whole engine must function inclusive cooling and all other issues and it was a DB engine called DB 606 and DB 610.

@ altsym

from the timeline it could happened but realy I don't know it.

 

[Milosh]

DonL,

A little off subject but didn't III./JG 27 use the 1.98ata (2000ps) DB 605's in trials around December 1944?

No it was a unit of JG11***. III./JG27 was one of the 4 units 'cleared' for use of 1.98ata, iirc March 22 1945.

*** there is some confusion on whether it was II./JG11 or 11./JG11. There was 11 1.98ata Bf109Ks in JG11 at the end of Dec 1944. Flugzeugbestand und Bewegungsmeldungen, II./JG11

 

[altsym]

Yes you are correct. Thank you for the additional information. I found the document the talks of II./JG 11 for December 1944:

 

[jim]

Dear Jim,

that's one of the rare issues we have to disagree.
I can't see where the BMW 801 was a failure.
It was reliable in late 1942 and offers more Steig und Kampfleistung then any other german engine at 1942.
There are certain issues about BMW you have to consider.
BMW was with Bramo the two biggest radial engine producer at germany and both came from the civilian aviation line. Siemens didn't want to enlarge Bramo at the timeline 1934/1935, so Bramo was socialized from the RLM and sold to BMW. Both companys produced their civilian line BMW 132 (P&R 1630) and Bramo 323 (Bristol Jupiter), both heavy modified from both companys, but both had relative old production lines and tools.
The fusion of Bramo and BMW happened since 1937/38, BMW new engine factory was built not until 1938 (Junkers and DB factorys were built much earlier) and through the fusion, the civilian market and the failure of the BMW 139, BMW was very late in the military engine development with the BMW 801, which was developed out of the BMW 139 and Bramo 329.
The main issues for BMW/Bramo was the tooling of the new built engine factory at 1938, because it was this late, BMW had to fight with endless other companys about good around toolings to equip their engine factory. This fighting holded on till 1943 and BMW had not as much modern allround production tools as DB and Junkers.
Anyway from a rational viewpoint it was more then clear for the RLM to fund a a new military radial engine from this two fusioned engine companys (advertisement 1935), to get the human resources (engine engineers) and production lines to work for the military development.

BMW/Bramo was compare to DB and Junkers a very small company 50000 workmen at 1944 (half of this slave laboured) and was able to develop the BMW 801 and the BMW 003 and put both in mass production.
The BMW 801 is to my opinion absolutely comparable to the Wright 2600 and very equal in performance.
The most issues of BMW/Bramo was their late change to the military development of engines, so they had major issues with production tools, human resources (engine engineers) and not the reputation of Junkers and DB and were always number 3 at the RLM, also at the attention and treatment through the RLM.

Mr DonL
Thank you for your very informative rensponse. Very interesting informations about BMW
However , i am afraid that i can not change my mind about the BMW801. It may have been a good engine CONSIDERING the difficulties that BMW was facing, but in absolute terms was mediocre, and thats was was important for the german pilots.
In 1942 was providing more Steig und Kampfleistung than any other german engine , but was heavier and draggier
Its power to weight ratio was always very mediocre, even using C4 fuel . In bombers installations was even worse. Thats a mortal shortcoming for a fighter engine
Could not use MW50 untill 1945, and its altitude performance was terrible until the last day of the war
While Bmw 801 is widely considered reliable after mid 1942 , i meet losses reports because of engine malfuctions in Fw190 units during the entire war
No matter the reasons , its development was very slow . In early 44 was totaly outclassed even at low altitudes (Of courseDB 605A was outclassed as well at that time frame)
Overall i consider it a good engine in 42, average (at best) in 43, outclassed in 44 and terrible in 45
According to Mr Crumpp, even BMW801F with 2400PS (c4 fuel/MW50) would give little ,if any, speed advantage over the Jumo 213A/MW50 (B4 fuel/MW50 2100ps), at SL because BMW was more than 9% draggier
Even if it was equal to the wright 2600 , is that a compliment?

 

[davebender]

R-2600 Case History

R-2600-3 series engine failed its 150-hour type test (July 1939), largely because of the PD carburetor

Most important point here has nothing to do with the carburetor.

1,600hp R2600 engine was conducting 150 hour test during July 1939. About three years before BMW801 engine could pass a similar test. Probably about the same time 1,600hp DB603 engine would have attempted a similar test if program funding hadn't been cancelled during 1937.

 

[wiking85]

R-2600 Case History

Most important point here has nothing to do with the carburetor.

1,600hp R2600 engine was conducting 150 hour test during July 1939. About three years before BMW801 engine could pass a similar test. Probably about the same time 1,600hp DB603 engine would have attempted a similar test if program funding hadn't been cancelled during 1937.

Considering that Germany was not allowed to develop military aviation engines from the 1920s-early 1930s BMW made fantastic progress on their radial engines given that they started so late. IIRC their first foray into developing a large hp engine was first based on a US design and then their own research from early 1930, unlike the US, which had been developing radials non-stop since WW1.

 

[davebender]

R2600 engine development began during 1935. DB603 engine development began during 1936 (before it was cancelled during 1937).

If RLM desires BMW to development a large radial engine they should fund development NLT 1936. By 1939 it's too late. Germany was staring war in the face so they must manufacture engines which are production ready or close to it.

 

[wiking85]

R2600 engine development began during 1935. DB603 engine development began during 1936 (before it was cancelled during 1937).

If RLM desires BMW to development a large radial engine they should fund development NLT 1936. By 1939 it's too late. Germany was staring war in the face so they must manufacture engines which are production ready or close to it.

The R2600 was based on previous experience from 1918 on of building radial engines, the BMW 801 was't.

In the 1930s, BMW took out a license to build the Pratt Whitney Hornet engines. By the mid-30s they had introduced an improved version, the BMW 132. The BMW 132 was widely used, most notably on the Junkers Ju 52, which it powered for much of that design's lifetime.

In 1935 the RLM funded prototypes of two much larger radial designs, one from Bramo, the Bramo 329, and another from BMW, the BMW 139. BMW bought Bramo soon after the projects started; unsurprisingly BMW folded the Bramo engineers into the BMW project, cancelling the Bramo design. The resulting proposal was essentially a two-row version of the BMW 132, the 1,550 PS (1,529 hp, 1,140 kW) BMW 139.

Radial engines were rare in European designs as they were considered to have too large an area for good streamlining and would not be suitable for high speed aircraft (the US Army agreed, see hyper engine). However, radials were often used in American and Japanese fighters at the end of the 1930s, and improvements in the cowlings for radial engines were reducing the concerns about drag.

So the BMW801 was started from the BMW 132 and the failed 139, which, within two years, turned into the 801. The Germans were not used to using them for high speed, high powered aircraft either, yet made remarkable progress in that direction by 1942. I agree with you about the DB603, but as far as the BMW 801 goes, I think it was a worthwhile project and the Germans did the best they could given their starting situation in radial development (they messed up in so many other places though, including the DB603).

 

[davebender]

If it's worthwhile then why wait until 1939 to begin development?

BMW132 was in production by 1934. That's when development of next generation radial engine should have begun.

 

[wiking85]

If it's worthwhile then why wait until 1939 to begin development?

BMW132 was in production by 1934. That's when development of next generation radial engine should have begun.

The design needed to be refined until it was possible to upgrade it, just like when the BMW 801 come online they didn't immediately jump to the next design.
They waited until 1938 because until then they were working on the BMW 139 (since 1935), which was replaced by the 801 when the 139 proved to be problematic.

The main concern was providing cooling air over the cylinder heads, which generally required a very large opening at the front of the aircraft. Tank's solution for the BMW 139 was to use an engine-driven fan behind an oversized prop-spinner, blowing air past the engine cylinders, with some of it being drawn through S-shaped ducts over a radiator for oil cooling. However this system proved almost impossible to operate properly with the BMW 139; early prototypes of the Fw 190 demonstrated terrible cooling problems. Although the problems appeared to be fixable, since the engine was already fairly dated in terms of design, in 1938 BMW proposed an entirely new engine designed specifically for fan-cooling that could be brought to production quickly.

The BMW 801 would eventually be fitted with a magnesium alloy cooling fan that rotated at 1.72 times the crankshaft speed (3.17 times the propeller speed).[2] This provided effective cooling although at the cost of about 70 PS (69 hp, 51.5 kW) required to drive the fan when the aircraft was at low speed. Above 170 miles per hour (270 km/h), the fan absorbed little power directly.[2]

 

[davebender]

Jumo210 entered production during 1935. Junkers began working on larger Jumo211 the same year.

DB600 engine factory was constructed during 1936. Daimler-Benz began working on larger DB603 engine the same year.

Why did BMW require a lengthy vacation before beginning work on next generation air cooled radial?

 

[Civettone]

Focke Wulf tested 3 prototypes to assess performance of Fw 190 with DB 603. Fw 190 V-13, V-15 and V-16. The last one flew in August 1942. There were no major problems with the installation and in a few months production could have been started. I have created a graph comparing Fw 190 A and C performance.

This seems misleading. A Fw 190C with a DB 603 with 2000 hp would not be available until 1945. Even the DB 603E was stuck at 1,800 hp. I still have my doubts if DB 603s with methanol injection ever reached operational status.
The Fw 190C as appeared in 1942/1943, without annular radiator, had a top speed of around 685 km/h.

The DB 603 had serious relaibility issues until late 1943. Nevertheless, given the production figures available, it should have been possible to have the Fw 190C operational in time for Big Week.

Kris

 

[Shortround6]

If it's worthwhile then why wait until 1939 to begin development?

BMW132 was in production by 1934. That's when development of next generation radial engine should have begun.

Why did BMW require a lengthy vacation before beginning work on next generation air cooled radial?

You have walk before you can run.

You also need a market for your product. If the German Military says they want liquid cooled engines trying to sell them air cooled radials is going to be hard. Getting them to pay for R&D might be even harder.

P W, Wright, Bristol, and Gnome-Rhone pretty much had the world export markets sewn up. P W and Wright also had a much larger domestic commercial market to sell new/improved engines to and they were NOT dependent on military orders for either survival or new product development.