Expert: D. Norkus - 3/8/2007

Question
Hi Dottie, is it possible for a commercial airplane such as the Boeing 747 to execute a complete barrel roll? Would such stress on the airframe cause it break up or would it hold? Is it even possible? What are the dangers involved?
Thanks.

Answer
Yes, it is possible to roll a 747, though such an aerobatic maneuver isn't something one would do in a transport category aircraft. A 1G roll would not stress the airframe at all, nor would it cause it to break up. (Moderate turbulence would "stress" it more. Those jets are built to handle quite a load. As an example, see this video about Boeing wing stress tests-
http://www.clipstr.com/videos/Boeing777WingTest/   

In 1955 Boeing test pilot "Tex" Johnston did actually roll a predecessor of the 747, their first four engine jet the 707.
He did what was called a "barrel-roll" although but some consider it an "aileron roll" as the plane rotates on its longitudinal axis at a constant altitude, rather than describing a "barrel loop" where the nose is pulled up and the aircraft makes a vertical circle with an altitude change.

You can see more on that event at these links:

http://www.youtube.com/watch?v=rILk6-4SMJQ
http://www.historylink.org/essays/output.cfm?file_id=390

Dottie