Pegasus Countdown Timeline

Time Event
T-3:15:00 NASA Launch Team – Management on Station
T-2:20:00 Flight Crew enters L-1011 Aircraft
T-2:20:00 Prestart Checklist (L-1011)
T-2:18:00 Engine Start Poll
T-2:10:00 GO for Engine Start
T-2:10:00 Start Engine 2
T-2:10:00 Start Engines 1&3
T-2:10:00 Aircraft Hatch Closure
T-2:10:00 Aircraft Stairs Removal
T-1:45:00 Pre-Taxi Checklist complete
T-1:45:00 Flight Termination System Activation
T-1:45:00 Voice Checks completed
T-1:15:00 GO for Taxi
T-1:15:00 Taxi
T-1:03:00 Status Check
T-1:00:00 Ready for Takeoff Poll
T-1:00:00 GO for Takeoff
T-1:00:00 L-1011 Takeoff
T-1:00:00 Chase Plane Takeoff
T-0:30:00 Chase Plane Visual Inspection
T-0:30:00 Report on Turbulence, Winds, Clouds
T-0:15:00 Release Mechanism armed
T-0:12:00 Flight Termination System Verification
T-0:12:00 Avionics to internal Power
T-0:09:00 Weather Status Report
T-0:09:00 Weather GREEN for Launch
T-0:09:00 Peak Power has Passed
T-0:09:00 L-1011 on Course to Drop Point
T-0:07:00 Range Status Validation
T-0:07:00 Transient Power on
T-0:07:00 Verify Vehicle is safe
T-0:05:00 NASA Launch Manager – Final Status Check
T-0:05:00 Avionics on internal Power
T-0:00:45 Fin Battery Activation
T-0:00:20 Fin Status Check
T-0:00:20 Fin Heading Status Verification
T-0:00:10 Pilot confirms GO for Launch
T-0 Pegasus release
T+0:00:05.00 Pegasus Orion 50S IGNITION