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That Time a Boeing 717 Went Inverted During Testing

Cool as a cucumber even as the jet hurtled towards the ground.

Yes, this is a real video!

During stall testing of the 717 program (formerly the MD-95), the aircraft departed controlled flight.  That’s a nice way to say that the jet stalled, rolled, and went inverted. The test pilots on board masterfully recovered the jet and survived to live another day.  Here’s the video proof:

With every new aircraft type, test pilots are tasked to test the limits of aircraft. With great preparation, they meticulous plan every maneuver. The flight testing typically confirms computer analysis and helps ensure that the normal flight envelope is safe. The test pilots also test maneuvers outside of the normal envelope.

The test pilots recovered the aircraft and lived to fly another day.

This video is both fascinating and yet pretty disturbing too. We did some research and put together some details that shed some light on the highly unusual flight.

According to a comment on a similar video posted on Vimeo, the 717 was on a test flight in warning area W-291 over the Pacific off the coast of California.  The particular 717 was the first off the line.  The aircraft had previously experienced some unusual stall characteristics.  This test was an attempt to determine why so that engineers could solve the issue.

In the video above, you can see that the pilots initiated a powered approach to stall in a climbing right bank. As the angle of attack increases, the jet appears to stall, then rapidly rolls left, and snaps inverted over a span of about 1 1/2 seconds.  The test pilots were prepared. They pulled the power to idle as the speed rapidly climbed (you can probably hear Bitchin’ Betty scream “overspeed”).  The crew then accepts the unusual attitude, and works to reduce the roll (most likely using a combination of rudder and the control tabs). They then pulled on the yoke to recover from the unusual attitude.  After congratulating each other that they saved the jet, they gingerly returned the jet to normal flight, returned to base, and then most changed to a fresh pair of underwear.

The test pilots did many things right.  While the aircraft most likely exceeded the +2.5G load limit, they limited any asymmetric forces on the jet by not attempting to ‘pull’ on the yoke while the wings were not level. Once they leveled the wings, they had to pull to return to level flight and arrest the very steep descent. They avoided the temptation to pull aggressively in order to minimize altitude loss. An aggressive pull  could’ve over-G’d the aircraft further and led to a secondary stall and/or spin.

The flying days for this particular test aircraft were limited. This test aircraft was later retired and broken up. Of the 156 717s built, 155 remain flying today.  The last Boeing 717 was produced in 2006.

If you are a MadDog or 717 pilot, we’d love to hear your perspective on this incident.  Post your thoughts in the comments below.

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Written by Avgeekery

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