The following was claimed on the aviation site:

In 1981, after years of development and testing, Columbia made its maiden voyage into orbit. Unexpectedly, on re-entry, the nose pitched up much higher than planned. Quick thinking and deployment of the airbrake beneath the rear fuselage (but not the vertical stabilizer "clamshells") prevented potential disaster.

It was later determined that the extreme heat of re-entry at 17,500 mph ionized the atmosphere underneath the nose of the Orbiter enough to torque it upwards more than even the pitch stabilizing influence of the delta wing could handle.

Quick googling for Columbia shuttle 1981 plasma lift comes up empty.

If it does and it's a true story, why would it nose up the Shuttle? The reentry videos I've watched from inside the orbiter, looking from the zenith windows, seem to suggest the plasma is more near the aft, so if it does create lift, wouldn't that be a nose down?

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    $\begingroup$ Plasma is created by the shock formed from the leading edges and flows around the craft $\endgroup$
    – user20636
    Commented Sep 30, 2019 at 22:07

1 Answer 1


This appears to be a garbled recounting of a problem that occurred during STS-1 entry due to a mis-match between predicted and actual hypersonic pitch trim.

enter image description here

Image Source

All that happened was that the body flap (see aft of Orbiter on diagram) extended 5 degrees more than predicted (which did cause the body flap to see higher heating than predicted as well). There was no "quick thinking" - the body flap was placed in automatic mode when the Orbiter entered the sensible atmosphere - and it was not an "air brake" - it was a pitch control device and a heat shield for the main engines.

At a dynamic pressure of about 0.5 lb/ft2, the body flap was positioned to automatic. Elevon body flap interaction was normal. The body flap automatically positioned itself to about 80 percent and appeared to remain there down to about Mach 15. The elevons were within their trim limits.

(p. 137, emphasis mine - note 80 percent on the gauge corresponds to ~15 degrees, see final diagram in answer)

The commander didn't start flying manually until Mach 4.8 (roll/yaw) and Mach 2.5 (pitch) (p. 138) and even that was temporary. He gave control back to the computers until the vehicle was subsonic and approaching the Heading Alignment Cylinder.

Source: STS-1 Orbiter Final Mission Report, Flight Test Problem Report #39

enter image description here

Note that body flap movement downwards is considered a positive deflection.

enter image description here

Image Source - Shuttle Crew Operations Manual - page 2.7-17

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    $\begingroup$ Superb, thank you! / Why would the extra deflection cause exceedance of pitch attitude? When the elevons are deflected down they result in pitching down, why not the same for the body flap, why was it a pitch up? $\endgroup$
    – ymb1
    Commented Sep 30, 2019 at 22:50
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    $\begingroup$ The automatic control system was working to put the pitch attitude where it should have been by moving the body flap. I doubt there was ever a pitch excursion, it's just that the body flap moved more than predicted to keep the pitch where it should have been. ISTR the sign on the body flap deflection was backwards from what we might expect. I'll research that and put it in the answer. $\endgroup$ Commented Sep 30, 2019 at 22:55
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    $\begingroup$ Yeah, body flap is positive down (sigh). Editing answer. $\endgroup$ Commented Sep 30, 2019 at 22:57
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    $\begingroup$ It's talking about the position of the body flap, not the orbiter. Orbiter pitch during entry was way more than 8 or 9 degrees, more like 45 degrees. $\endgroup$ Commented Sep 30, 2019 at 23:00
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    $\begingroup$ If only more Stack Exchange Q&A's were as carefully written as this Flight Test Problem Report! $\endgroup$ Commented Sep 1, 2020 at 17:12

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