Robertson X-1 STOL Airplane Project of 1958

[hesham]

From Aviation magazine 1958,

the Robertson Aircraft Corporation designed a STOL high wing monoplane Project,it powered by
two Lycoming 340 hp CSO480 engines,all details are here.

 

[walter]

Dear Hesham!
The X-1 was built and reportedly some tethered flight teste were carried out. Some sources claim there may have been a connection with the Fairchild company
and that the X-1 may have carried the Fairchild M-257 or M-258 designation (speculative!).
Please see attached photo and text.
2/4-seat experimental S/VTOL
two 340hp Lycoming GSO-480 piston engines
wingspan 24ft; length 33ft; height 6.917ft
DETAILS: The X-1 (M-257 or M-258) Aero-VTOL was an experimental S/VTOL aircraft developed by the Robertson Aircraft Corporation (formed in October 1956 as a division of Aero Design, Inc). The aircraft also appeared in 1956 and in its construction a modified Aero Commander 500 fuselage and many other parts and components were used. The X-1 used the so-called propeller slipstream deflection principle and underwent only very limited testing and reportedly made its first (tethered) flight on 8 January 1957. However, further development was soon halted. The aircraft may have been referred to as the X-1 (Roberton) or M-257/M-258 (Fairchild) and it had two 340hp Lycoming GSO-480 engines and the wings were equipped with large full-span t/e flaps providing the S/VTOL characteristics. The wingtip tanks also served as endplates.
Production: 1

 

[hesham]

Hi,

may the Robertson MR-3 was based on this design,the MR-3 was probably a VTOL concept ?.

 

[Barry Collman]

Dear Hesham!
The X-1 was built and reportedly some tethered flight teste were carried out. Some sources claim there may have been a connection with the Fairchild company
and that the X-1 may have carried the Fairchild M-257 or M-258 designation (speculative!).
Please see attached photo and text.
2/4-seat experimental S/VTOL
two 340hp Lycoming GSO-480 piston engines
wingspan 24ft; length 33ft; height 6.917ft
DETAILS: The X-1 (M-257 or M-258) Aero-VTOL was an experimental S/VTOL aircraft developed by the Robertson Aircraft Corporation (formed in October 1956 as a division of Aero Design, Inc). The aircraft also appeared in 1956 and in its construction a modified Aero Commander 500 fuselage and many other parts and components were used. The X-1 used the so-called propeller slipstream deflection principle and underwent only very limited testing and reportedly made its first (tethered) flight on 8 January 1957. However, further development was soon halted. The aircraft may have been referred to as the X-1 (Roberton) or M-257/M-258 (Fairchild) and it had two 340hp Lycoming GSO-480 engines and the wings were equipped with large full-span t/e flaps providing the S/VTOL characteristics. The wingtip tanks also served as endplates.
Production: 1

The STOL aircraft pictured is the Robertson M-287 "Rainbow", N7829B, msn 1 powered by two Lycoming GSO-480. I understand the FAA fie was destroyed many years ago, but will check that is indeed the case.

I understand Robertson were also working on a VTOL tilt-wing example based on an Aero Commander and seem to recall a photo of this, probably copied from a newspaper or magazine. Does anyone have any further info ?

 

[Stargazer]

and that the X-1 may have carried the Fairchild M-257 or M-258 designation (speculative!)

Nothing speculative here. M-257 was the designation applied by Fairchild to the Robertson X-1.
Be careful: M-258 was the designation for the Fairchild Friendship (license-built Fokker F.27)

The STOL aircraft pictured is the Robertson M-287 "Rainbow", N7829B, msn 1

Did you mean "M-257" here?

 

[Barry Collman]

Nothing speculative here. M-257 was the designation applied by Fairchild to the Robertson X-1.
Be careful: M-258 was the designation for the Fairchild Friendship (license-built Fokker F.27)

Did you mean "M-257" here?

No - I do mean M-287. Although there is no paperwork regarding the history of N7829B, the FAA's internal paperwork items are confirmed as showing it as a "Robertson M-287 Rainbow". And, I don't think Fairchild were involved at all in this project. It was also not a VTOL aircraft, but a STOL. There was a VTOL project, but I'm not certain that Robertson were involved. I seem to recall it was a modified Aero Commander 680, with a tilt-wing, but perhaps 'built' by students at some facility (In Dallas ?). The M-287 aircraft was photographed at the Aero Commander R&D facility at Norman (Westheimer Field), Oklahoma, as Aero Design acquired control of Robertson Aircraft Corp in December 1956. Evidently Robertson called it a "twin engine vectored slip-stream vehicle".
The Fairchild M-257 must be a completely different aircraft.