This thread seems to throw up a few basic questions. The first is whether the DB 603 could have been a widely available and reliable engine in 1943. The second is related question is why the RLM did not make more effort to ensure that it was widely available and reliable. I think that the reason is that they expected the Jumo 213 to outperform it. Here are a few links to discussions of those issues on other fora:
DB 603 numbers
http://www.luftwaffe-experten.org/forums/index.php?showtopic=8971
DB 603 reliability in 1943
http://www.luftwaffe-experten.org/forums/index.php?showtopic=16941
DB 603 oil problems
http://www.pprune.org/archive/index.php/t-353495.html
DB 603 - Jumo 213 comparison
http://www.ww2aircraft.net/forum/aviation/db-603-vs-ju-213-a-34815.html
DB 603 handbook
http://www.ww2aircraft.net/forum/engines/handbook-db-603-a-27291.html
Incidentally, AFAIK the first use of indium in bearings was by Pratt & Whitney (see page 7 of
www.enginehistory.org/Frank%20WalkerWeb1.pdf)
The other question is why the Fw190 v13 performance did not make a stronger impression. The v13 has been made as a model and the little that we know is discussed in this review
http://hsfeatures.com/features04/fw190v13jh_1.htm
One problem seems to have been that even better performance might have been achieved using a turbocharger. However, Germany hardly managed to get a turbocharged BMW into production before the end of WW2. I conjectured that they might have lacked the necessary alloys. Alternatively the engineers and metallurgists needed to make one work were exactly those needed to make a jet work (a turbocharged piston engine is a jet with an unusually complex combustion chamber) and were thus unavailable. The other was that the RLM preferred the Jumo 213. However, until the firing order was changed, the 213 was totally unreliable.
Thanks for all of the info!
I couldn't access the second link though.
I thought the following was interesting:
http://www.ww2aircraft.net/forum/aviation/db-603-vs-ju-213-a-34815.html
11-22-2012 02:56 AM #21
tomo pauk
Well, with a full 1943 to work out the bugs out of 603A (during that time maybe banning the Notleistung, as in 601E/605A case?), the engine became reliable in late 1943/early 1944.
11-22-2012 09:47 AM #26
Siegfried
The DB603A was somewhat troublesome in its first 6 months of service but it soon enough broke through to 100 MTBO barrier in early 1944. The PW R-2800, BMW 801 were all roughing it at around 25 hours when they first went into service. The CW R-3350 was still problematic when the aircraft flew its first missions in June 1944, I believe the 5 upper rear cylinders needed replacement at 25 hours due to burned out valves and poor cooling flow there. Low MTBO doesn't preclude effective service though it does preclude large scale service due to the heavier than usual maintenance requirements.
The DB603 also saw service in two variants, the standard DB603A and the DB603AA which compromised takeoff power a little in return for considerable extra power at altitude. Before the end of 1944 another variant, the DB603E was entering production. It had about 5% more low altitude power than the DB603A and at about 1800hp also had about 5% more high altitude power than the DB603AA.
The DB603EM also would have allowed the Ta 152C to enter service in late 1944. It produced 2260hp and was essentially a DB603E with MW50 but unlike the the plain DB603E it needed C3 fuel to exploit its Water Methanol injection system.
The German production schedule for a massive increase in C3 fuel production was starting to ramp up in late 1943 as new plant and new technology came on line only to be disrupted by the bombing campaign and endless fighters now opperating from the continent after d-day. Hence the DB603LA, which had a two stage supercharger (without intercooler I believe) and DB603L (with two stage supercharger and intercooler) had to be subsituted as both could produce serious levels of power with MW50 but without the use of the temporarily dubious C3 fuel.
Hence the oil campaign seems to have derailed the Ta 152C production by several months by forcing the Luftwaffe to emphasise more fuel flexible engines meaning that the Jumo 213E powered Ta 152H entered production first. About 4 Ta 152C with DB603LA engines were delivered.
11-22-2012 10:26 AM #27
tomo pauk
If it looks like I'm bashing the DB-603, I don't. The LW would've been better off with it in Fw-190 airframe from late 1943.
I'm not posting all of the discussion, but it looked like the DB603 had problems relating to it being cancelled in 1937, restarted in 1940, and entering service production in 1942. It required some time to work out the bugs, very similar to the BMW 801 and other engines, including some allied ones.
So the engine functioned by didn't meet the 100 hours until overhaul. The BMW 801 didn't, as did several other aero-engines when they started combat service. By putting the engine into service with the FW190C it would have still functioned, but would have resulted in limited numbers. Basically it was the FW190C or the Me410, because of the competition for engines and their initial unreliability meant that those that were produced wore out earlier than usual. Part of the problem was that parts for it were destroyed when the Allies bombed the Ruhr in 1943, which caused critical damage to a parts subcontractor, which meant that production was delayed until those parts became available. Still more than 2000 were produced in 1943, so with at least 500 or so FW190s that works out just fine. By 1944 the reliability issue is resolved, so that isn't a problem any longer and production doubles, meaning many more FW190s can be produced.
It seems that the agreement in that thread is that the FW190C with the DB603 is the preferable option, because even with the problems of the early DB603As, they were needed and would have been functional until the engine reliability issues were worked out, which it seems they were by late 1943. So that means the early 1944 slaughters are then blunted because we have the FW190C in service now with reliable engines that have broken the 100 hour test comfortably. The airframe is proven and in production, while the engine is also in production while the changes to improve reliability are relatively non-disruptive to the production of new engines.
So while a 1943 start for the FW190C would have to mean limited numbers until late in the year because of the engine issues, which means no massive replacement program for the Me109 in 1943, they would still be in service and have their bugs worked out a few months before they are critically needed, which means that hundreds of them could be operational in time for the February deadline when Big Week starts. Then production ramps up, which then results in the ME109 being replaced increasingly and the FW190C contesting the skies on an equal footing to the P51B/C/D.