| XRJ47 | |
|---|---|
| Type | Ramjet |
| National origin | United States |
| Manufacturer | Wright Aeronautical |
The Wright XRJ47 was an American ramjet engine developed in the 1950s to help propel the rocket-launched SM-64 Navaho supersonic intercontinental cruise missile. Although the design flight Mach Number was 2.75, a peak flight speed of Mach 3.0, at altitudes up to about 77000 ft, was envisaged. This very large ramjet had a number of design problems, including some difficulty in light-up. Development of the Navaho missile was cancelled along with the ramjet engine in 1957.
The single cone supersonic intake supplied ram air to a long annular diffuser terminating at the aft-mounted cylindrical combustion chamber. The centreline of the intake system was gently curved, presumably to line up the intake face with the flow-field of the missile nose section.
The combustion chamber flame-holder consisted of a center-body pilot region, with three annular V-gutters interconnected by slanted radial V-gutters. Fuel jets were of variable area design.
A heat-shield, with multiple exit ports, provided cooling air for the jetpipe and the fixed area ratio convergent-divergent propelling nozzle. The exit diameter of the nozzle equaled that of the combustion chamber.
Data from Aircraft Engine Characteristics Summary: Ram-jet XRJ47-W-5,[1] Preliminary evaluation of flight-weight XRJ47-W-5 ram-jet engine at a Mach number of 2.75[2]