Aircraft occupant protection system

A crash attenuation system for an aircraft, the system comprising:

• an airbag assembly carried by the aircraft and inflatable generally adjacent an exterior of the aircraft, the airbag assembly comprising:
• first and second inflatable airbags;
• and
• a vent system, the vent system comprising first and second vent passages supported by the aircraft, the first and second vent passages each having a respective one of first and second continuously adjustable vent areas through which gas can escape from within the first airbag;
• a gas source system in fluid communication with an interior of at least one of the first and second airbags for inflating at least one of the first and second airbags with gas provided by a gas source;
• a sensor system for detecting selected crash conditions;
• and
• a control system for receiving data from the sensor system, the control system being configured to activate and adjust the first vent system and the second vent system at least prior to impact, based upon flight conditions, the first vent system and the second vent system being independently controlled of one another based on the detected crash conditions;
• wherein the first vent passage extends between a first opening in the first vent passage and a second opening in the first vent passage;
• and
• wherein the first opening is in fluid communication with the interior of the first airbag, and the second opening is positioned beyond an outermost extent of the first airbag when the first airbag is inflated.