Dornier 217 hypothetical

[J.A.W.]

A couple of points for consideration re Do 217;
1, A fast ship - say compared to a B-25 or even B-26, on the straight level, cant`ve been too 'under-powered' -maybe Brown didn`t like twins per se?
2, A faster ship, going downhill, being built stress-capable of dive-bombing meant the Do 217 had pretty good G-factor limits, including V-ne ratings, which gave some tactical options the B-25/B-26 could not match, or for maybe even evading an NF Beaufighter during Baedeker, `43..

 

[davebender]

Depends on what you are comparing. I suspect Eric Brown was thinking in terms of Me-410, Mosquito and Ju-88G light bombers. Larger Do-217 won't have the same power to weight ratio using similiar engines.

If you want Do-217 to perform like a Ju-88G then it needs Jumo 222 engines. Then it would have the power to fly with one engine shot out.

 

[Shortround6]

In a single engine plane if you loose the engine the plane is going down.

In a twin engine plane it depends a lot on the power loading. Some twins will fly rather nicely on one engine ( once trimmed out), others even when trimmed and balanced have a negative rate of climb on one engine= plane looses altitude even with the engine at full power and flying straight and level. Any maneuver, even a gentile turn, causes a lost of lift and an increase in drag.

Speed does not equal "high power", it equals low drag. Allison powered Mustangs were very fast but had a poor power to weight ratio and didn't climb well. P-40s gained speed over the P-36 but gained little power and a lot of weight. They went faster but didn't climb as well.

Twin engine bombers often had 4-7 man crews. Loosing and engine on take-off in an under powered twin could result in the loss of both the aircraft and crew. A plane with a bit more power may give the pilot enough time to trim the plane out and do a circuit to get it back on the ground. Plane probably isn't high enough for the crew to bail out.

The British made their share (and more?) of under powered twins.

 

[J.A.W.]

Didn`t Robin Olds say something like " I sometimes got home from Germany on 1 engine - flying the P38 , but I always got back on 1 engine, flying the P-51.."

Some twins were tricky on one mill, even a fairly high powered job, like the Mosquito, being critical in engine failure V 1 rotate situations, due to assymetric aero issues.
Speed is still a factor of power/drag, maybe the DH designers really got it right with deletion of defensive armament on their Mosquito.

I recall reading about a canny veteran Do 217 skipper who lightened his machine as much as possible, inc losing guns [ gunner] - since he reckoned that a determined fighter pilot will invariably press in hard, no matter what you throw back at him, evading attacks by using a performance edge was a better bet..

 

[johnbr]

 

[vikingBerserker]

Nice!

 

[Old Wizard]

 

[J.A.W.]

Sadly, although there is no intact Do 217 to see, the USA has a ex- Do 217 BMW 801 'power-egg' on display,
interestingly, the BMW 'kommandogerat' unified control system was also used on the bomber mills..

That must've helped in flying the machine if A2A combat was in prospect, & was in advance of most US fighters..