Lockheed puts Pratt to work on hypersonic motor

Pratt & Whitney Co.'s rocket-motor division has been hired to work on a prototype for a combo jet turbine-ramjet propulsion system capable of moving a low-orbit military vehicle at hypersonic speeds.

Aerospace and defense giant Lockheed Martin Corp. signed a 10-month contract with Pratt & Whitney Rocketdyne for preliminary design of a high speed accelerator for a turbine-based combined-cycle propulsion system, which could support flight up to Mach 6 -- six times the speed of sound.

The value of the contract was not disclosed.

Pratt said such a vehicle could be used for strike and reconnaissance missions.

Based on its experience assembling and testing motors for the space shuttle and Atlas and Delta rockets, Rocketdyne said the aim of its contract is to create prototype designs for a dual-mode ramjet combustor with related control and fuel system components.

The turbojet engine, Pratt said, would launch the reusable vehicle at takeoff until speed reaches Mach 3, at which time the ramjet would kick in to propel the vehicle to Mach 6.

According to answers.com, a ramjet is a jet engine that propels aircraft by igniting fuel mixed with air taken and compressed by the engine in a fashion that produces greater exhaust than intake velocity.

Rocketdyne also has been asked to provide specifications for a facility to test the motor prototype

Rocketdyne program manager Cal DeFreese says Pratt was brought aboard because of its past success developing and ground testing its own combined-cycle engine technology.

Pratt's work will minimize the time and risks associated with developing Lockheed Martin's hypersonic engine, DeFreese said.

Pratt & Whitney Rocketdyne, based in West Palm Beach, Fla., is a unit of Hartford-based United Technologies Corp.