Allied-inspired Engines powering German strategic bombers

With the fall of France and events shortly thereafter, the Germans acquired the following:

*Douglas A-20 'Havoc' aircraft and their Wright Cyclone-18 engines from the United States making 1600-1700 HP each.

*British two-stage supercharged Merlin XX engines (making 1480 HP themselves).

*Farman F.220 airframes of French design, their engines producing only about 1100 HP each and capable of carrying 5190 kg of bombs over 1200 miles with those engines.

-He 177 designs use the ever-troublesome DB 610 design (as did the Ju 288 with the DB 606 'twinned' engine) while the Fw 191 used the rarely working Jumo 222 engines.

So...

1. Could the Germans have used the Cyclone-14 to create a working strategic bomber in early to mid 1941 or tied two together somehow to make a Cyclone 28 using two engines placed together or a native-designed, Allied-inspired engine?

2. Do British two-stage superchargers solve some of the German engines problems by themselves?

3. If the Germans succeed in creating a 2500+ HP engine before mid-1942, what would its impact be on the war? How about if it were placed in a fighter aircraft?
 
The French A-20 was known as the Douglas DB-7. Supply was limited to variants powered by the P&W R-1830. The French flew perhaps 70 sorties with them, lost 8, according to one source, and skedaddles back to Vichy Africa with the remainder. The Germans did have access and stocks of the same engine, which powered the Hawk 75, and sold some to Sweden to power the FFVS J-22.

The British would liked to have had some two-stage Merlins themselves, at the time.

The Germans made some use out of Gnome Rhone 14M&N engines, and told the French not to develop the 14R, which powered the Bloch 157, or the Hispano 12Z, and had no interest themselves.

The Wright Cyclone 14, the R-2600, was in the class of the BMW 801, a 14 cyl. There were projected plans to build an 18 cylinder and a doubled 28 cylinder 802 and 803, but such things take time, and the jets are coming, and are cheap and easy.
 
The Wright Cyclone 14, the R-2600, was in the class of the BMW 801, a 14 cyl. There were projected plans to build an 18 cylinder and a doubled 28 cylinder 802 and 803, but such things take time, and the jets are coming, and are cheap and easy.

The 801 started life as a twin row development of the single row P&W Hornet engine they were building under license during the '30s. It was the BMW 139, and powered the first prototype of the FW190, an 18 cylinder twin row engine. BMW had recently merged with Bramo, who had a 14 cylinder twin row engine that also had teething issues.

The two together resulted in the 801
 
The 801 started life as a twin row development of the single row P&W Hornet engine they were building under license during the '30s. It was the BMW 139, and powered the first prototype of the FW190, an 18 cylinder twin row engine. BMW had recently merged with Bramo, who had a 14 cylinder twin row engine that also had teething issues.

The two together resulted in the 801

In my own ethereal way, I have formulated a slightly different tale. The Bramo 323 was based on the Bristol Jupiter, and the two-row 329 wasn't going anywhere but the garbage, being longer in the tooth than the equivalent BMW version of the Hornet. Bramo contributed nothing but engineers to the new engine development. I'm thinking that rumors to the effect that the BMW139 being 18 cylinders are false, and that it was a 14 cyl, like the 801. The 801 was based on the Hornet, but completely different. The Hornet was obsolete and the BMW 801 decidedly was not.

Forgot to mention that the Hornet built under license became the BMW 132 in 1930, and underwent independent development at that time. One of the engineers involved, Rudolph Ammann, was paperclipped after the war. He was the one involved in the novel engine management system.
 
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The 801 started life as a twin row development of the single row P&W Hornet engine they were building under license during the '30s. It was the BMW 139, and powered the first prototype of the FW190, an 18 cylinder twin row engine. BMW had recently merged with Bramo, who had a 14 cylinder twin row engine that also had teething issues.

The two together resulted in the 801
AFAIK the 801 had nothing to do with the Bramo work, their engineers were just brought in to help once the decision was already made by BMW to reduce to 14 cylinders and use knowledge gained in testing to redesign their 139 design.

In my own ethereal way, I have formulated a slightly different tale. The Bramo 323 was based on the Bristol Jupiter, and the two-row 329 wasn't going anywhere but the garbage, being longer in the tooth than the equivalent BMW version of the Hornet. Bramo contributed nothing but engineers to the new engine development. I'm thinking that rumors to the effect that the BMW139 being 18 cylinders are false, and that it was a 14 cyl, like the 801. The 801 was based on the Hornet, but completely different. The Hornet was obsolete and the BMW 801 decidedly was not.
I've read that they used the work they did on the 139 was 18cyl, but the knowledge they gained from working on it led them to start over with fewer cylinders as an easier path, which led to a much shorter development period because they got it right from the beginning thanks to knowing what not to do from the 139.
 
I've read that they used the work they did on the 139 was 18cyl, but the knowledge they gained from working on it led them to start over with fewer cylinders as an easier path, which led to a much shorter development period because they got it right from the beginning thanks to knowing what not to do from the 139.

I'm just trying to balance out a mountain of conflicting information against what are presumed to be facts, as a BMW 18 cyl 139 would be 55.4 liters with only 1550 hp, weighing less than the 14 cyl 801 of 41.8 liters. A 43 liter 14 cyl 139 makes more sense, given the then current state of tune for the BMW 132.
 
In my own ethereal way, I have formulated a slightly different tale. The Bramo 323 was based on the Bristol Jupiter, and the two-row 329 wasn't going anywhere but the garbage, being longer in the tooth than the equivalent BMW version of the Hornet. Bramo contributed nothing but engineers to the new engine development. I'm thinking that rumors to the effect that the BMW139 being 18 cylinders are false, and that it was a 14 cyl, like the 801. The 801 was based on the Hornet, but completely different. The Hornet was obsolete and the BMW 801 decidedly was not.

Not rumor.
http://www.thisdayinaviation.com/tag/bmw-139/
If you dig around for pics, you can count 9 in the first row.

The 801 used derivative/improved Hornet jugs on an light alloy crankcase designed for fan cooling, since both engines were having cooling issues on the 2nd row.

'Obsolete' much in the same way that the early marks of the Wright R-3550, an 18 cylinder of very similar displacement (129 was 3380) in that the cylinders needed to be redone for more cooling area in additional fin area.

They went with the 14 for a smaller diameter, and less drag, plus fan cooling

The biggest thing Bramo supplied was engine controls, the throttle controlled adjusting the mixture and other settings automatically

US engines were all manual, with many individual controls, so much more pilot effort in twirling knows and sliding levers for the same effect.

The USA should have went with auto controls and the fan for cooling, and BMW should have kept developing the 139 into a 'modern' 3380 cubic inch radial

That's what the Luftwaffe really needed, esp. for bombers.
 
I'm just trying to balance out a mountain of conflicting information against what are presumed to be facts, as a BMW 18 cyl 139 would be 55.4 liters with only 1550 hp, weighing less than the 14 cyl 801 of 41.8 liters. A 43 liter 14 cyl 139 makes more sense, given the then current state of tune for the BMW 132.

Look at pictures of the FW-190 V1

But yes, there is conflicting info, but how do you turn the BMW 132, a single row 9, into as two row 14 as part of making a fast upgrade of a two row Hornet?

The original 1937 R-3350 was around 2000 hp. and with the formulation of US fuel, US designs almost always had more HP/c.i. than the German of similar size.

It even had worse cooling problems at that power level, the first XB-29 needed 17 engine changes to log 100 hours of flight. It had been more reliable in the Consolidated XP4Y Corregidor flying boat at lower power settings
 
bmw 139

“Flugmotoren und Strahltriebwerke,by von Gersdorff, Grasmann and Schubert” says the BMW 139 was a 14 cylinder two row radial. The BMW 140 was the projected 18 cylinder engine and started development in spring 1937 but was cancelled.
 
“Flugmotoren und Strahltriebwerke,by von Gersdorff, Grasmann and Schubert” says the BMW 139 was a 14 cylinder two row radial. The BMW 140 was the projected 18 cylinder engine and started development in spring 1937 but was cancelled.

Interesting, nothing really googles up on the 140 in English, a little bit in German.

Looks like the two were confused in most sources. Would explain the differences.

That said, I think they should have stuck with the 140 for a 2000 HP class bomber motor
 
That said, I think they should have stuck with the 140 for a 2000 HP class bomber motor

When Wright built the 14-cyl. R-2600, they developed and patented a dynamic balancer. When Pratt built the R-2800, they didn't use a balancer, and spent a year developing one, eventually using the Wright patent. The Bristol Centaurus didn't use a balancer but did have some active motor mounts to dampen the vibes. This worked until the Brabazon, where it didn't. Would the BMW 140 require a solution to torsional vibration? More power creates new problems, requiring solutions. Sometimes, they are found, and sometimes not. Sometimes, it's just a matter of time, and effort.
 
The allied engines are good but getting the High-octane aviation fuel will do great wonders, fuel efficiency and increase performance for the German aircraft....
 
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