the interior of the airbag application_number US 67956310 A description the present invention provides for an inflatable crash attenuation system for aircraft the system comprises an airbag that is inflated prior to impact and controllably vented during impact so as to prevent aircraft pitch over the present invention may be used on all models of aircraft for example helicopter fixed wing aircraft and other aircraft and in particular those that are rotorcraft the system of the invention improves on the prior art by providing automatic control of the venting valves based on sensed crash conditions thereby effectively shifting the center of impact pressure and preventing aircraft pitch over fig2 shows a helicopter 100 incorporating the crash attenuation system according to the present invention helicopter 100 comprises a fuselage 102 and a tail boom 104 a rotor 106 provides lift and propulsive forces for flight of helicopter 100 a pilot sits in a cockpit 108 in a forward portion of fuselage 102 and a landing skid 110 extends from a lower portion of fuselage 102 for supporting helicopter 100 on a rigid surface such as the ground a problem with rotor 106 or the drive system for rotor 106 may necessitate a descent from altitude at a higher rate of speed than is desirable if the rate is an excessively high value at impact with the ground or water the occupants of helicopter 100 may be injured and helicopter 100 may be severely damaged by the decelerative forces exerted on helicopter 100 to reduce.