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Old 8th May 2009, 16:08
  #435 (permalink)  
Dave_Jackson
 
Join Date: Apr 2003
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Mart,
But let me back peddle >-------> less induced velocity.
Sorry, but I do not understand.


Also pusher prop is effectively just revectoring streamtubes, ....... .
I respectfully disagree. This subject is considered here; DESIGN: UniCopter ~ Pusher Prop - General - Tractor vs. Pusher
__________________


As an aside; Re your mentioning of retreating blade (reverse velocity airflow).

There is an ongoing PPRuNe thread on the V-22 Osprey. The discussion basically relates to the effectiveness of the Tiltrotor configuration, and its Achilles’ heel, which is the difficulty of its blades to serve the requirements of both a propeller and a rotor.

The ABC configuration has it's own Achilles's heel, that being the extremely high drag/lift ratio from its retreating blades.

Eventually, there may be an interesting 'showdown' between the Tiltrotor and the ABC for 'Best in Breed', where the breed is 'VTOL+speed'.


Dave
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