WEB EXCLUSIVE: Next-Generation Ejection Seats to Include New Safety Features

The ACES 5 undergoing testing.

Photo: Collins Aerospace

The Air Force has tapped Collins Aerospace to provide more than 3,000 new ejection seats for its aircraft fleet. The equipment includes a number of safety improvements to prevent pilot injury, according to a company executive.

The Next-Generation Ejection Seat program will upgrade the existing systems on the F-15, F-16, F-22, B-1 and A-10. In October, the Air Force issued a pre-solicitation Justification and Approval notice for a sole-source contract to Collins Aerospace. Final negotiations and a contract have yet to be completed, a company spokesman told National Defense Nov. 12.

Collins Aerospace is offering its ACES 5 ejection seats to replace the legacy ACES II, a Collins Aerospace product which has been in service since the 1970s. The new equipment will be a significant step up, said Don Borchelt, the company’s director of ACES 5 business development.

The Air Force has new requirements that seat developers had to factor in, he said in an interview.

“The first requirement was to be able to accommodate the full anthropomorphic range,” to include pilots who weigh as little as 103 pounds all the way up to 245 pounds, he said.

“That's new, and it presents a significant design challenge for ejection seats specifically because a different weight occupant will shift that center of gravity significantly in the seat itself,” he noted.

A second new requirement is to increase the operational envelope of the system to 600 knots flying speed.

“The third thing … is the proliferation of helmet-mounted devices and helmet-mounted displays, which of course puts extra mass on the air crew's cranium, which is again another design challenge for engineers,” he said. “To accommodate that … we had to come up with some new design features.”

The system can automatically adjust the thrust that the air crew experiences during ejection based on the weight of the user. The technology is intended to reduce the risk of spinal injury.

“It just becomes a self-fulfilling chemical reaction to push a little harder for heavier weight occupants. Conversely, for lightweight occupants you don't want [thrusters] to push that hard,” he explained.

Additionally, right after the catapult fires, a passive head and neck protection system will spring into action.

“What tends to happen at high speeds is the pilot's cranium will roll off to the left or the right … which obviously can load up the neck and cause a neck injury that we don't want,” Borchelt said. “This will keep your head straight. This will keep your cranium from being hit by the wind … and keep the cranium from smacking back against the headrest.”

It also has passive arm and leg restraints to prevent flailing injuries.

“If you can't hold on to that ejection handle, the wind will tend to blow your arms back behind the seat, which could obviously injure your shoulders,” he noted. “That's not good if you're in bad guy land or in any situation, obviously — but particularly if you're in a combat situation and you're in hostile territory and you can't function as well because you can't get on the radio, you can't escape and evade.”

If an ejecting pilot can’t hold onto the seat’s handle, the ACES 5 will catch their limbs with webbing and prevent dangerous flailing, he said.

The seat also comes with a stability package that includes a gyro-stabilized pitch stabilization mechanism, which stabilizes the seat and the pitch axis. That capability is important for injury prevention throughout the ejection sequence, he said.

The system also comes with a new parachute, the GR7000. It is a “monumental leap” over legacy chutes, Borchelt said.

It's not a performance "chute like the Golden Knights [use] or something like that,” he said. “It's still a fairly a typical configuration round parachute, but it does have some forward drive, reduced oscillation solution and a little bit of steerability.”

Giving pilots better parachutes helps them avoid landing in trees, power lines or other hazards, he noted.

Additionally, it has "a lot of features in terms of the porosity of the fabric and the way the thing opens,” he said. “It's got a little softer opening to prevent that opening shock and injury to pilots at higher speeds.”

The parachute must meet the Air Force requirement to accommodate a suspended weight of 337 pounds, to include the air crew’s full survival kit plus all the gear they could be wearing. It must also enable a lower decent rate — 21 feet per second — to mitigate the risk of injury during landing, he noted.

“If the air crew has to eject, they need to be able to hit the ground in a condition where they can escape and evade, get on the radio, get rescue forces in there so that they can live to fly and fight another day,” Borchelt said.

A variant of the new ejection seat that meets requirements for the B-2 program was slated to be delivered before the end of this year. The Air Force has also selected the ACES 5 to be installed on the next-generation T-7A Red Hawk trainer aircraft, he said.

Borchelt anticipates international interest in the new system.

“We're working very closely with some foreign partners out there who are very closely watching the development of the seat with the [U.S.] Air Force,” he said. “The survivability enhancements to be able to hit the ground running, the injury reduction methods that we have demonstrated are absolutely interesting to a lot of folks worldwide.”

Topics: Air Power