Originally posted by WHATTHEHELL
Read about the test flight of the DO-335 from Capt Brown.
the Do-335 had two engines, one pusher, other puller. The after propeller was known to have a quite low efficiency. However, you can afford losing some of the efficiency of the after engine if the configuration allows for a good deal of efficiency in other departments.
The Do-335 did allow for that efficiency, was a two-engined aircraft with much less roll inertia that any other twin engined plane, and allowed for a two-engine configuration with much less drag than the others (to the point that the reduction of drag more than compensated for the loss of eficiency of the aft propeller). Not to mention the engines rotation pretty much gave the plane no torque effects at all.
The vibration problems required some tweaking but after 2 years of testing of prototypes they were quite solved. The Shinden never had that development time.
In short:there were a lot of benefits from the configuration, one of them making good the loss of eficciency of the after propeller. It was a SOUND configuration.
The shinden was an one-engined plane, which wasted a lot of engine power, had vibration problems that could be solved with enough development time (time the model never had because it was rushed into production before time), and in short, had more drawbacks than benefits.
While the Do-335 pusher-puller configuration was a sound one, the Shinden one wasn't. At least from my point of view and from what I know at this point... I repeat that there may be something I don't know about this configuration that makes it worthy. That's why I asked about those possible benefits in the first place
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