Farnborough Air Show

New JSF ejection seat designed for a perfect fit

 - November 15, 2006, 7:37 AM

It’s not only movie theater seats that are now designed with the fuller figure in mind. Martin-Baker (Hall 4 Stand D4) says its system development and demonstration (SDD) ejection seat, most recently selected by Lockheed Martin for its F-35 Joint Strike Fighter, contains features designed to accommodate larger aircrew.

The UK firm’s marketing manager, Richard Staines, said the SDD seat, known within the JSF community as the US16E, “provides an unprecedented balance of performance parameters, such as safe terrain clearance and physiological loading limits, pilot boarding mass and anthropomorphic accommodation ranges.”

The seat weighs less than 180 pounds and provides 30g of crash protection. Yet it is designed to fit a broader range of aircrew statures, ranging from smaller women to larger men–all in full flight gear. A seat-tilt capability of nearly six degrees about an attachment point on the cockpit floor ensures that it meets the full range of these physique criteria.

Actuator encoder feedback to the aircraft databus is provided to allow automatic adjustment, helmet-mounted display information and zone restriction. This ensures that pilots cannot put themselves in a potentially unsafe position by transgressing, for example, the forward ejection clearance line or their proximity to the canopy.

An auto-eject system has been introduced to counter the lift-fan failure condition for the F-35B STOVL (short takeoff vertical landing) aircraft.

SSD is a development of the Mk16 product line that has been successfully integrated in the Raytheon Texan II (JPATS), Eurofighter Typhoon, the NASA T-38N upgrade program and other aircraft platforms. “From an ejection standpoint, SDD has introduced challenging requirements from cost and technical performance perspectives,” explained Staines. “Some nine years away from full-rate production, the production seat price has already been fixed. The seat, like all other aircraft components, feeds into the aircraft cost model and will be meticulously tracked.”

For the helicopter community here at Farnborough, Martin-Baker is also displaying its nonarmored crashworthy crew seat. The seat is flying on Sikorsky’s S-92, currently in civil operation over both North Sea and Gulf of Mexico oil fields.

Mounted on two light alloy vertical rails and support structure, the helicopter crew seat allows the occupant to adjust seat height electrically. It features a five-point harness and automatic shoulder reel. A control enables the shoulder harness to be locked or unlocked for torso mobility. The light alloy support structure incorporates an impact attenuation system and floor attachments to the flight deck floor.

The attenuation system absorbs the seat’s energy by causing a tube to be flattened as it passes through rollers. These rollers minimize the effects of friction, providing a steady and predictable performance. The design also features an anti-rebound mechanism that controls occupant deceleration in both directions, and holds onto the lowered seat bucket in the event of an aircraft rollover.

The seat is designed to meet the crashworthy requirements of U.S. and European FAR/ JAR Part 29, the flammability resistance of FAR Part 25.853(b) and TSO 127 certification. It has also been fully tested to the environmental requirements of MIL-STD-810, which has involved subjecting it to vibration, sand and dust, shock, salt, fog, humidity, hot and cold temperatures and static loads.

The company reports that Martin-Baker seats have saved 7,154 lives, including 20 this year.