Telescoping arm restraint system

An ejection seat 200 with a seat frame 204 having a seat back 208 and a seat pan 206 adapted to support an occupant, a propulsion system and a backstop (250 and 252) designed to deploy laterally outward from the seat back to form a forward-facing structure; the backstop includes lower 212 and upper 218 support arms which telescope in response to ejection of the seat is defined. An ejection seat comprising a plurality of shrouds 202 connected to the lower and upper support arms and designed to form the forward-facing surface when the seat is ejected is also defined. The lower and upper support arms may comprise lower (370,fig3C) and upper (371,fig3C) base members connected to a seat frame respectively, via ratcheting hinges (214 and 220). The lower support arm may comprise a first lower telescope member (372,fig3C) slidably engaged with the lower base member and a second lower telescoping member (374,fig3C) slidably engaged with the first lower telescoping member. The upper support arm may comprise a first upper telescope member (373,fig3C) slidably engaged with the upper base member and a second upper telescoping member (375,fig3C) slidably engaged with the first upper telescoping member.