The Stairs Go Down
Robert Rynerson. CC BY 2.5. Picture source
Alone in the back of the plane, he lowers the rear stairs into the freezing dark, and a little after 8 pm he jumps.
November 24, 1971, about 7:45 to 8:13 pm, over southwest Washington
The story
A few minutes after takeoff, he sends Tina Mucklow to the cockpit and tells her to close the curtain behind her. As she turns, she sees him in the aisle, tying something around his waist. It is the last time anyone is known to see him.
In this story, he works quickly. He has cut cord from one front parachute to lash the money down. He straps on one of the plain military back parachutes, the kind that cannot be steered but opens hard and fast. Perhaps the paper bag he carried all day holds boots and gloves. Nobody ever found out what was in it.
Around 8 pm a light in the cockpit shows the rear stairs are down. The pilots ask on the intercom if he needs help. He says no. Outside, the air is below freezing, and there is sleet in the dark.
At about 8:13 pm, the tail of the plane jerks upward. The pilots trim it level again. In this story, that bump is a man stepping off the bottom stair into the night, with a parachute on his back and about 21 pounds of money tied to his body.
What the record says
It was minus seven degrees Celsius outside the plane, it was dark, and there was sleet and hail.
HistoryLink.org Essay 1997
However, somewhere between Seattle and Reno, Nevada, a little after 8 p.m., Cooper jumped out the back of the plane with the parachute and ransom money, disappearing forever.
FBI, Artifact of the Month caption for the Cooper plane ticket (2016)
That moment was the last time another human being knowingly had visual contact with Dan Cooper.
HistoryLink.org Essay 1997
Mucklow told the FBI she last saw him standing in the aisle with a cord tied around his waist, about four minutes after takeoff. The aft-stair warning light came on around 8 pm, and at about 8:13 pm the crew felt the tail pitch upward; in a later FBI test, pushing a weight of about 200 pounds off the stairs of the same jet caused the same motion. First Officer Rataczak told the FBI this happened near Portland's northern suburbs. The crew's last intercom message, 'Sir, we are going to land now, please put up the stairs,' got no answer. The contents of the paper bag were never known; the FBI only wondered whether it held a jump suit and boots.