Gentlemen,
I am rather shocked by the responses to this thread! We seem to have forgotten some very basic theory here!
The thrust of a jet turbine is not produced by the jet efflux impinging on the air behind the exhaust nozzle. Thrust is purely a reaction to the acceleration of gas through the engine itself. Thus, all the magic has happened by the time the gas reaches the nozzle of the engine. The thrust vector originates at the engine itself.
Thrust vectoring is different, in that variable geometry nozzles are used to provide lateral forces by means of redirecting the jet efflux. The point from which the forward thrust acts remains unchanged.
The addition of long ducted exhaust nozzles to jet engines only serves to reduce net thrust due to losses in the ducts themselves. The issue of asymmetric thrust is almost entirely dependant of the position of the engines, and cannot be alleviated by the addition of "ducting". If there was mileage in the ducting idea, the men in white coats would have implemented them a long time ago!
unproductive comments deleted
Regards
Cuban_8
Last edited by john_tullamarine; 28th March 2004 at 01:01.