Air-Launched Weapons

USAF tests engine for Gray Wolf low-cost cruise missile

20 March 2020

The Air Force Research Laboratory working with Northrop Grumman and Technical Directions Inc. (TDI) recently tested a new turbojet engine under the low-cost cruise missile programme known as Gray Wolf. Source: AFRL

The US Air Force (USAF) has tested a new low-cost turbojet engine to power air-launched cruise missiles being developed under the Gray Wolf programme.

The Air Force Research Laboratory (AFRL) announced on 19 March that, along with Northrop Grumman and Technical Directions Inc. (TDI), it had for the first time flight-tested the TDI-J85 engine. This test, the AFRL said, involved multiple inflight engine starts, as well as operation at high altitude.

“The engine met performance expectations for thrust and surpassed fuel efficiency expectations. The engines tested accumulated sufficient inflight operating time, building confidence in the design durability,” the AFRL said.

As noted by the AFRL, the engine design focuses on affordability and ease of manufacture. “It is the first engine in its class and price point to successfully operate at altitude. With the success of this test, AFRL is [a] significant step closer to launching a low-cost cruise missile,” the laboratory said.

The Gray Wolf is an Office of Secretary of Defense (OSD)-directed prototype production and demonstration of a low-cost cruise missile. “These low-cost cruise missiles will offer a stand-off solution with a variable payload capability, meaning the missiles are designed to cruise for distances greater than 250 n miles and can accommodate multiple mission profiles. Additionally, the programme [will] explore using multiple Gray Wolf missiles in a networked swarm to meet an evolving warfighter mission requirement,” according to the AFRL.

In order to meet its ambitious timeline and cost requirements, the AFRL is developing the cruise missile and its engine as a whole. This has been challenging, according to the director for the AFRL Colonel Garry Haase.

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