The pilot and copilot documented D.B. Cooper’s jump time:
“At approximately 7:40 pm the 727 took off with only Cooper, pilot Scott, flight attendant Mucklow, copilot Rataczak, and flight engineer H.E. Anderson aboard.
“The crew soon noticed a subjective change of air pressure, indicating that the aft door was open.
“At approximately 8:13 pm, the aircraft’s tail section sustained a sudden upward movement, significant enough to require trimming to bring the plane back to level flight.”
http://en.wikipedia.org/wiki/D._B._Cooper
“At approximately 10:15 pm, Scott and Rataczak landed the 727, with the aft airstair still deployed, at Reno Airport. FBI agents, state troopers, sheriff’s deputies, and Reno police surrounded the jet, as it had not yet been determined with certainty that Cooper was no longer aboard; - but an armed search quickly confirmed that he was gone.”