1. Chris Valeski Ryan Wagner
Ejection Systems
Chris Valeski
Ryan Wagner

3. Ejection Seat Components
Catapult - moves seat up a set of rails
Rocket - propels seat away from aircraft
Restraints - holds passenger in seat
Parachute - allows passenger to descend at safe speed
*it is possible that catapult and rocket be the same component
Survival Provisions

4. Current Generation of Ejection Systems
parachute is deployed immediately
Pilot-seat separation not required
Seat senses airspeed and altitude of the aircraft and selects an appropriate time delay for ejection
Seat and parachute are deployed in an optimal manner

5. Timing an Ejection - 0 Seconds
Pilot pulls cord
canopy is jettisoned or shattered
catapult initiates
sends seat up rails

6. Timing an Ejection - 0.15 Seconds
Seat Clears the ejection rails at approximately 50 ft/s.
Rocket catapult ignites
Yaw motor fires
Burn time of motors last approximately 0.10 seconds

7. Timing an Ejection - 0.50 Seconds
Seat has cleared the aircraft by 100 to 200 feet
Seat-man-seperator motor fires and catapults crewmember from seat along with equipment
Drogue gun fires parachute

8. Timing an Ejection - 4 Seconds
Main parachute is fully deployed

9. Ejection Forces on Human Body
Typical ejection consists of forces between 12 G’s and 20 G’s
A 180 lb. crewmember would feel a 3600 lb force at a 20 G force ejection.

10. Ejection Movie http://www.aviationexplorer.com/su27_airshow_video.htm

11. Future of Ejection Systems
“Smart” seat – Combines digital technology and highly controllable propulsion systems
On-board digital computer would instantly calculate an optimum ejection trajectory, which would then be executed by a more controllable rocket motor
Increased ability to eject in high altitude and high speed cases.
New propellants

12. Factors Impacting Future Ejection Systems
Cost
Weight
Rapid decrease in number of ejections

13. Sources
Horn, Henry. Evolution of an In-Flight Escape System. AIAA Paper No : 1981.
Sadler, Robert. Propulsion’s Contribution to the Success of Aircrew Emergency. 39th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit: July 2003.