Overspeed?
Thread Starter
Joined: Aug 2016
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From: Ilmington, Warwickshire
Overspeed?
Please can someone explain whether overspeed is a pilot error or a result of weather conditions? i.e Could a flight deck just be unlucky and get caught out or is it result of negligence?
Joined: Feb 2001
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From: The Winchester
Wot TangoAlphad said...
Deliberately fly at "max" speed and then go a knot over max due turbulence...I suspect that might be called an error of judgement .
Fly at reasonable speed (e.g normal cruise speed), hit unforecast/unreported clear air "wave" and go above max speed...I'd say that was unlucky.
Did you have a specific scenario in mind?
Deliberately fly at "max" speed and then go a knot over max due turbulence...I suspect that might be called an error of judgement .
Fly at reasonable speed (e.g normal cruise speed), hit unforecast/unreported clear air "wave" and go above max speed...I'd say that was unlucky.
Did you have a specific scenario in mind?
Thread Starter
Joined: Aug 2016
Posts: 2
Likes: 0
From: Ilmington, Warwickshire
Wot TangoAlphad said...
Deliberately fly at "max" speed and then go a knot over max due turbulence...I suspect that might be called an error of judgement .
Fly at reasonable speed (e.g normal cruise speed), hit unforecast/unreported clear air "wave" and go above max speed...I'd say that was unlucky.
Did you have a specific scenario in mind?
Deliberately fly at "max" speed and then go a knot over max due turbulence...I suspect that might be called an error of judgement .
Fly at reasonable speed (e.g normal cruise speed), hit unforecast/unreported clear air "wave" and go above max speed...I'd say that was unlucky.
Did you have a specific scenario in mind?
Yes, the scenario was last week crossing a mountain range in Central Europe during very stormy weather. A mate was FO and said the warning suddenly went off on his 737. The day was actually the same one that an aircraft was seen on the news, having to abort a landing in Austria because of extreme crosswinds.
Joined: Jun 2001
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From: UK.
Could be caused by a rapid increase in headwind, reduction in tailwind, updraft (autopilot lowers nose to hold altitude) or, in the case of Mach limit, a rapid reduction in air temperature.
The 'Gotcha' is that, as you (or the autothrust) reduce thrust to contain the speed excursion, the cause may rapidly reverse, requiring increased thrust
The 'Gotcha' is that, as you (or the autothrust) reduce thrust to contain the speed excursion, the cause may rapidly reverse, requiring increased thrust
Joined: Mar 2001
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From: I wouldn't know.
Stormy weather and mountain range, a nice recipe for wave formation which will increase the likelyhood of speed envelope excursions quite a bit.
Depenind on cost index and the resulting cruise speed one can be very close to VMO anyway, add a mountain wave and you‘re set up for over speed.
Depenind on cost index and the resulting cruise speed one can be very close to VMO anyway, add a mountain wave and you‘re set up for over speed.
