EXDOAK said:The Doak 20 and Doak 22 were design studies by Doak Aircraft in the late 50's - early 60's. Doak Aircraft went out of business in 1961 and sold their VTOL designs, drawings, data, etc. to Douglas Aircraft. A couple of Doak engineers also went to Douglas. Douglas submitted a proposal to the US Army for an updated Doak Model 16 (which was rejected) , and a proposal to the US Air Force/US Navy, in competition with Bell Aircraft, for a 4-duct transport similar to the Doak Model 22. Although the Doak submission was superior in most respects and Doak had actual flight test experience with a 2-Duct VTOL airplane, Bell received the contract for the X-22. (I was involved in the desigh of the Doak 16 and ran the flight test program.)
hesham said:the upper artist drawing is for Doak;
hesham said:My dear Skyblazer,
please see reply # 2.
Probably designed under the leadership of Bell, but still designated as Bell-Doak designs,
here are two other ducted fan designs, I found in an issue of Flugwelt from the '60s
(sorry, no more precise information about the source )
Very complex mechanism's, lots of moving parts. Safe? not much of a glide ratio if fans fail.Wonderful pictures! I'm afraid I do not have any information on the aircraft bu the Model 22 certainly resembles the Bell X-22A.
I have always wondered why the ducted fan VTOL capability never moved forward. It is safe, even gives VTOL aircraft a bit of stealthyness... enclosed rotors reduce aural and radar a bit. Would have worked wonders in urban environments.