XV-15 litho - NASA's History Office

Transcendental Model 2
The Transcendental Model 2
Convertiplane 62 (figures A-2 and A-3)
was a high-wing monoplane with a
helicopter-type rotor mounted at each
wing tip. It was configured with a conventional
airplane empennage and a
fixed-position tricycle landing gear. In
addition to vertical takeoff capability,
the Model 2 Convertiplane was
designed to perform rolling takeoffs
combining the lift from the rotors and
the wing at gross weights above the
maximum vertical takeoff weight.
In hovering and slow flight, control
was achieved by the use of conventional
helicopter rotor cyclic and collective
blade angle controls. At higher
airspeeds the conventional fixed-wing
airplane tail control surfaces and
ailerons provided the means for flight
path control.
A Lycoming O-435-23 opposed sixcylinder
reciprocating engine was
mounted vertically in the fuselage
behind the crew area. Power was
transmitted through a main transmission
located above the engine to drive
shafts which provide input to the outboard
gearboxes. The spanwise shafts
incorporated flexible couplings to
accommodate the angular misalignments
of the drive system. The outboard
gearboxes and the shafts that
drove the rotors could be tilted by the
pilot through the use of electrical actuators.
This permitted the rotors to be moved from a horizontal plane (for the
hover and low speed flight mode) to a vertical plane (for higher speed forward
flight) when sufficient airspeed was attained for the wings to support the aircraft.
62 Transcendental Model 2 information from Janes, All the World’s Aircraft, 1955-1956.
Figure A-2.
Transcendental Model
2 three-view drawing.
117