Ad: This forum contains affiliate links to products on Amazon and eBay. More information in Terms and rules
Were they historically able to boost the BMW engine earlier than the did historically? If so why did they hold back?
The "C3 einspritzung" was used already in Summer of 1943 by the bomb-lugging Fw-190s.
FWIW, the power chart for the DB 603A, with added lines for the BMW 801D (red, Notleistung; pink is overboost roughly) and Jumo 213A (blue, Notleistung). The DB 603A really trumps the BMW, not only power-wise, but it cuts drag, allows for a big gun to be carried centrally, the intake will use the ram air in a convenient fashion so the aircraft's rated height will be at circa 7 km. Can use MW 50 for even more power, especially under 6 km (no ram), Notleistung can be used for 5 minutes instead of 3 min for the 801.
Problem with DB 603A is that it is not that reliable and available in 1943.
(open the pic separately for hi-res)
View attachment 287009
And let s forget that the 801D was using C3 fuel while db603 B4. And still the 801 was inferior!
I believe that after 1942 the 801 was a really BAD engine as fighter engine. It crippled the Fw190 during the most important war years. In my opinion the Fw190/Bmw801 combination enjoys today much more fame than historicaly deserves.
And let s forget that the 801D was using C3 fuel while db603 B4. And still the 801 was inferior!
I believe that after 1942 the 801 was a really BAD engine as fighter engine. It crippled the Fw190 during the most important war years. In my opinion the Fw190/Bmw801 combination enjoys today much more fame than historicaly deserves.
Don't think the 801 was a bad fighter engine in 1943. It was just fully rated in October 1942, and it's power was sufficient before late 1943. Where it came short was the air intake layout, it needed an external intake that is both not that draggy and not 'squashed', so the aircraft rated height is at about 7 km, instead at 6.3 km. Let's not forget that both RAF and USAF specified the Fw-190 as a target to equal or better (though the Bf-109F-4/G-2 were also tough things to beat). From Autumn of 1941 until 1943, the Fw 190 was very much an useful fighter, and in many of it's properties the best in the world.
Now for winter of 1943/44 and on, the Fw-190 certainly needed a better engine. Whether the DB 603, Jumo 213, or even the 2-stage BMW 801 if it can be pulled out.
That's not the end of the world as long as the aircraft has excellent roll.
Rolling fast wont do anything like that to your aircraft - unless rolling imparts heavy yaw forces on that type and you mush/spin out that way.
The Fw 190's high speed stalls would come from turning (pitch).
The advantage of the 801 I can see would be higher max continuous power than the 605, provided WM/50 is implemented. (same reason the 605+WM/50 was unattractive on the 190 -the high alt models still seem like they might have been worth the trade-offs though, potential gain in range/endurnace too, and mounting space for a motorkannone, but that's getting into a whole other topic with alternate Fw-190 variants)
And there you go into the topic of diverting engines to the 190 as well, granted with the more universally advantageous 603. (that airframe seemed to be one of the most sensible places to be puting 603s as well as 213s, and the 603 allowed for a centerline cannone mounting as well)
The DB-605 AS(M) still seems like a useful candidate too, though, especially in as far as matching/beating the Mustang above 20,000 ft. (compared to using the 801, not the 603 or 213)
So a universally good fit for the 190, except perhaps for fighter-bomber specific variants.The max continuous power of the engine will not be affected by MW 50. The fully rated DB-605A/AM was making 1080 PS at 5.5 km, vs. 1180 PS of the BMW 801D, however the BMW is more draggy, it is heavier, and it consumes more (both total and specific consumption). Installing a 20mm or even 30 mm to fire through the prop means less drag than having 2xMG 131s under cowling of the Fw 190.
The DB 605AM was making about as much power at 4-5 km as the the overboosted BMW 801D. The DB 605AS/ASM really trump the BMW 801D at altitude: more power, less weight, less drag.
Again, this seems a bit like the Hurricane production situation and only relevant if it was impossible to replace 109 volume production with other types. (albeit a much more limited argument due to the scarcity of ASM engines)As above - especially the 605ASM would be a very useful engine for hi-alt work - at 6.4 km (21000 ft) it makes 1500 PS, or same as the DB 603A, with less weight bulk. Problem with 605ASM is a crucial one for a tool of warfare - it is available too late to matter, and any engine produced is needed for the Bf-109 to keep them competitive at ETO/MTO. The 605
So a universally good fit for the 190, except perhaps for fighter-bomber specific variants.
You've got those DB-605's slated for Bf-109s and 110s, so politics aside, plans would have had to be in motion to shift production earlier. Expand Fw-190 production or risk having fewer engines avilable to 109s. (110s might be a significant loss too and retooling them to BMW-801s might or might not have worked -pushing those engines onto Ju-88s might have made more sense though ... and if the 110s were /actually/ needed, Jumo 211s might have been adequate and much easier to displace the 601s/605s with than 801s, including the issue of limited range/fuel capacity of the 110)
Relegating some 109s to be Jumo 211 powered might have been a reasonable trade-off (for sheer volume production if 190s couldn't totally supplant 109 volumes), but performance would be limited and no motor cannon support was provided. (go back to using wing cannons as standard?) The 801 would seem a bad fit for the 109. Heavy, draggy, and fuel hungry. Maybe use Jumo powered 109s on the Eastern front where altitude performance wasn't as critical? (maybe have more precedent for MW/50 systems being developed for the 211?) Somewhat like the Avia S-199 but less of a hack job with properly mated prop and reduction gearing, and preferably J/N/P models rather than F.
Plus, relegating more of those 'lesser' 109s to the Eastern front and diverting even more 190s to the ETO might have been a worthwhile trade-off. (especially with the potential potency of DB powered 190 variants)
Bombers/heavy/night fighters with more 801s, 190s with more 605s (and 603s), and supplemental 109s with 211s might have made some sense. (again, if 109s couldn't be phased out entirely)
There's also the He-100 to consider, which might have made an even better fit for the DB-605 (or 601) but was also a tighter/limited design. The 190 is bigger and heavier, but remarkably flexible in overall design, more space for expansion and weight gain, fuel, armament, and a variety of engines. (plus it was in development at the same time as the He-100, so unless the He-100 was actually easier to manufacture, ramping up/second sourcing 190 production would seem most useful)
Again, this seems a bit like the Hurricane production situation and only relevant if it was impossible to replace 109 volume production with other types. (albeit a much more limited argument due to the scarcity of ASM engines)
Keeping 109s competitive in the ETO/MTO is only a problem if there's no alternative to displace them entirely ... at least outside of the Eastern front.
I'd displace the Bf 109 with a jet. Simple 1-engined job, with 2 cannons.