MIL-S-58095 Seat System: Crash Resistant, Non-Ejection, Aircrew, General Specification For

Pages 1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10

MIL-S-58095A (AV)

3.3 First article. When specified in the contract or purchase order a sample

shall be subjected to first article inspection (see 4.5).

3.4 Design. The seat shall position the pilot to permit comfortable operation

of the aircraft. Occupant survival in aircraft accidents shall be a primary

consideration in seat design. The seat shall be adjustable and provide a means

of crash load attenuation. The occupant restraint system, attaching hardware to

the aircraft, seat cushions, headrest and mountings for ancillary equipment are

a part of the seat.

3.5 Materials. Materials shall be as specified herein. When specifications

and standards are not specifically designated, selection of materials and

processes shall be in accordance with MIL-STD-143.

3.5.1 Critical Members. All structural members shall be fabricated from

ductile materials whose elongation is in excess of 10 percent. Critical

tensile and bending members, which, because of other design considerations,

cannot be allowed to appreciably deform plastically, may be designed of higher

strength materials having elongations as low as 4 percent for thin (less than

0.030 inch (0.8mm) thick) sheet materials. In all cases, the system shall be

designed to avoid brittle failure.

3.5.2 Flammability. Materials in their finished condition shall satisfy FAR

Part 25.853.

3.5.3 Megnesium. Magnesium alloys shall not be used.

3.6 Construction. All exposed portions of the seat shall be free from

projections and sharp edges that could catch or damage the occupant, crew

members or their clothing and equipment. Exposed edeges shall be rounded to

.04 inch (1.0mm) minimum radius and exposed corners to .5 inch (13MM) minimum

radius.

3.6.1 Interchangeability. The seat and its subassembly components which are

appropriate for replacement shall be functionally and dimensionally interchange-

able through tolerancing or manufacturing tooling.

3.6.2 Dissimilar Metals. Unless components are suitably protected against

electrolytic corrosion, contact between dissimilar metals shall not be used.

Dissimilar metals are defined in MIL-STD-889.

3.6.3 Joining and fastening. Riveting and welding may be used for assembling

the component parts which are suitable for this type of assembly. Safety

margins-for shear and tensile bolts shall be at least 5 and 10 percent,

respectively. Bolts less than 0.25 inch (6.Omm) in diameter shall not be used

in any single bolted connection. Nuts shall be of a self-locking type or be

safetied. Riveted joints shall be designed in accordance with MIL-HDBK-5.

Welded joints shall be in accordance with MIL-W-8604, MIL-W-45205, MIL-W-8611,

and MIL-STD-22.