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Yeah, the DB engineers end up at Jumo and help to work out the issues the Jumo series had with their experience. Radial engines are also a major option sooner.Jumo 211 family can fit the needs decently; since the DB family of engines is not around more resources go to later derivatives, like -N, -P -R.
The Jumo 213 is earlier sorted out, too?
Yeah, the DB engineers end up at Jumo and help to work out the issues the Jumo series had with their experience. Radial engines are also a major option sooner.
The Jumo route is quite interesting, as it simplifies production quite a bit, though with a corresponding reduction in high burst performance that the DBs gave.
What are the circumstances of the DB loss though?
The same as those for the loss of the Merlin and the loss of the V-1710: it's being posited for the purpose of discussion.
What the man said. We are here to discuss, hopefuly in a friendly and constructive manner. If some find that tedious, guess that's entirely heri problem.The same as those for the loss of the Merlin and the loss of the V-1710: it's being posited for the purpose of discussion.
I wish the Allison had the DB supercharger.
To my knowledge, the 605AM and 605A used the same one. Difference was the water-methanol injection, hence the M. The AS engines used the DB 603 supercharger for better high altitude performance.Which DB supercharger?
The one on the DB 601A.
The one on the DB 601E/605A
The one on the DB 605 AM.
each is different.
I suppose they'd lose the war.
That depends on when Jumo 211 development hits a technical road block.
Decision to build Genshagen engine factory was made during 1935 so that's when DB601 program would need to be cancelled. Presumably DB603 program would never exist as it was derived from DB601 program.
Junkers would have 1935 to 1939 to get Jumo 211 engine program in order. However if there were no other V12 option I suspect RLM would demand results (i.e. promising prototypes) NLT 1937. When Junkers fails to meet the deadline there would be a crash program (no resources spared) to find an alternate V12 engine. Alternate V12 might simply be resurrection of the cancelled DB601 program. Just as RLM historically resurrected canceled DB603 program during 1940.
Mid war technical snag.
Let's pick 1941. 1,340hp Jumo 211F engine works but engine has little further development potential.
1,340hp is adequate until mid 1943 so Germany has some time.
Fw-190A and BMW801 engine might be the big winner. Production might be increased and it fills the entire single engine fighter aircraft requirement during the final two years of WWII.
A major upgrade was started in 1940 in order to better compete with the 601, following in its footsteps with a pressurized cooling system. The resulting 211E proved to be able to run at much higher power settings without overheating, so it was quickly followed by the 211F which included a strengthened crankshaft and a more efficient supercharger. Running at 2,600 RPM the 211F delivered 1,340 PS and the 211J (a 211F with intercooler) delivered 1,420 PS. Further improvements to this basic line led to the 1,450 PS 211N and 1,500 PS 211P in 1943, they were equivalent to the 211F/J but with slight boost increases and running at up to 2,700 rpm. Continued development of the 211 line evolved into the 213.
When the Jumo 211 entered production in the late 1930s it used an unpressurized liquid cooling system based on an "open cycle". Water was pumped through the engine to keep it cool, but the system as a whole operated only at ambient atmospheric pressure, or only slightly greater. Since the boiling point of water is affected by pressure, this meant that as the aircraft climbed the temperature of the cooling water had to be kept quite low to avoid boiling, which in turn meant that the water removed little heat from the engine before flowing into the radiator to cool it.
In contrast, the 1940 Daimler-Benz DB 601E used a pressurized system that ran at the same pressure at all altitudes, even raising the boiling point slightly to about 110°C. This allowed it to use considerably less water for the same amount of cooling power, and it retained this power at all altitudes. Although otherwise similar to the Jumo 210 in most respects, the 601 was smaller and lighter than the 211, and could be run at higher power settings at higher altitudes, making it popular in fighter designs. The 211 was relegated to "secondary" roles in bombers and transports.
Junkers was not happy with this state of affairs, and started their own efforts to produce a pressurized cooling system as early as 1938. Experiments on the 211 proved so successful that it became clear that not only could the engine be built smaller, but could be run at higher power settings without overheating. Additional changes to strengthen the crankshaft and add a fully shrouded supercharger for increased boost resulted in the Jumo 211F model, which delivered 1,340 PS (1,322 hp, 986 kW) at 2,600 RPM, up from 1000 PS at 2,200 RPM in the first version 211A.
But this was only the beginning. After redesigning the engine block to a smaller external size to suit the increased cooling power - while keeping the same 150 mm x 165 mm bore/stroke figures, maintaining the 35 liter displacement of the Jumo 211 series - and then further increasing boost settings on the supercharger, the resulting 213A model was able to deliver 1,750 PS (metric hp) at 3,250 RPM. This made it considerably more powerful than the corresponding DB 601E which provided 1,350 PS, and about the same power as the much larger DB 603. Junkers decided to go after the 603's market, and placed the 213's mounting points and fluid connections in the same locations as the 603, allowing it to be "dropped in" as a replacement, with the exception of the Jumo's standard starboard-side supercharger intake (Daimler-Benz inverted V12 engines always had the supercharger intakes on the port side).
Impossible awesome Nazi tech will always win.
Impossible awesome Nazi tech will always win.