![Robert H. Edwards's Blog: Great 20th century mysteries - D. B. Cooper: incident at Cinebar - March 20, 2022 04:08 Robert H. Edwards's Blog: Great 20th century mysteries - D. B. Cooper: incident at Cinebar - March 20, 2022 04:08](https://i.gr-assets.com/images/S/compressed.photo.goodreads.com/hostedimages/1648067952i/32722514._SX540_.jpg)
Robert H. Edwards's Blog: Great 20th century mysteries - D. B. Cooper: incident at Cinebar - March 20, 2022 04:08
Aircraft Maintenance Engineers - What does this do? This is a photo of a airstairs on a Boeing 727. Many other rear engine aircraft have (or had) rear airstairs, including; DC-9 ,
![aircraft design - Was the 727 the last airliner whose doors could be opened in flight? - Aviation Stack Exchange aircraft design - Was the 727 the last airliner whose doors could be opened in flight? - Aviation Stack Exchange](https://i.stack.imgur.com/9koSW.gif)
aircraft design - Was the 727 the last airliner whose doors could be opened in flight? - Aviation Stack Exchange
![Robert H. Edwards's Blog: Great 20th century mysteries - D. B. Cooper: the Boeing test flights - June 08, 2022 07:47 Robert H. Edwards's Blog: Great 20th century mysteries - D. B. Cooper: the Boeing test flights - June 08, 2022 07:47](https://i.gr-assets.com/images/S/compressed.photo.goodreads.com/hostedimages/1655054479i/33048048.jpg)
Robert H. Edwards's Blog: Great 20th century mysteries - D. B. Cooper: the Boeing test flights - June 08, 2022 07:47
![PJ de Jong (PJ) on Twitter: "The Boeing 727 airstair at the rear of the aircraft. Convenient! http://t.co/5WVh7fv0Qw" / Twitter PJ de Jong (PJ) on Twitter: "The Boeing 727 airstair at the rear of the aircraft. Convenient! http://t.co/5WVh7fv0Qw" / Twitter](https://pbs.twimg.com/media/B15xgVQIEAA-c9n.jpg)