181–186 of 186 posts
Earlier quoted context omitted.
All modern Boeings (>= B777) are FBW (fly by wire) and have flight envelope protection. A 787 will absolutely not go over-speed: it will automatically throttle back.
Will throttling back help? The plane is pitched down 18 degrees and mach 0.9 KIAS.
Earlier quoted context omitted.
The outside of the airplane has a forward-pointing tube called a pitot tube. As the airplane travels forward, air is compressed into this tube. By measuring the pressure, you can derive the airspeed. However the higher you go, the lower the ambient air pressure is and so the "indicated airspeed" is not at all accurate. However indicated airspeed is still very useful as it measures the air resistance the aircraft is e…
On the subject of indicated airspeed, does the mach number have the same meaning? That is, if the aircraft had reached an indicated airspeed of Mach 1, would they break the sound barrier and experience a sonic boom?
They were truly at 0.9 mach, had they increased speed by 11% they would have broken the sound barrier, well before the indicated air speed would have read a >mach 1 number.
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The N/Kg conversion might be off by a factor of what, 1% in extreme cases (Denver)? Whereas IAS can easily be a factor of two or more different from the plain English sense of "airspeed".
My point is that airspeed is a vector measured relative to something . In this case, it's set to a specific situation (25C/101.3kPa/0% humidity) and then measured relative to the stagnation pressure at that point because then no matter those variables, the plane reacts more or less the same way for the pilot, who is the one who needs to understand what's happening. Your 'plain English' sense of 'airspeed' is pretty i…
I know the pilot needs a measure that behaves like IAS. I just think it's misleading to call the thing we measure "airspeed" when it can be so radically different from, well, airspeed.
> You have markers on runways, wind socks, etc. to all get a feel for what your IAS translates to on the ground and thus how much speed you're going to have when you hit the runway. That seems far more useful to me than having some kPa display on the dash.
I don't understand this argument. Surely if you were flying in a plane that displayed kPa those same markers etc. would give you exactly the same sense for how a given kPa reading translates into speed on the ground. All that would change would be that the conversion factor would be slightly different. Is "110 knots" any more intuitive (to a non-pilot) as a measure of everyday speed on the ground than "20 pascals"?
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The article states there was 198 souls on board
The article is confusingly worded, mentioning 25 passengers and 7 crew in another part... Which are also described as 25% of occupants, but that's not 25% of 198.
"“Up to 24% of the aircraft occupants were rendered temporarily unfit for duties following the incident,” the report adds, referring to 25 passengers and seven crew members."
I read that as 'up to 24% of the 25 passengers and seven crew members'. I completely missed the quote at the bottom (beneath the image) that refers to the 198 people. And you're right, the figures don't add up anyway.
What exactly did this 'automatic high-speed protection system ' do?
"As the aircraft pitched down, the aircraft’s captain – who was alone in the cockpit – attempted to disengage the autopilot and pull back on his sidestick"
Surly the autopilot would have disengaged when the pilot moved his seat forward and pushed the sidestick forward at the same time?
"With dual inputs being delivered, the A330’s flight protection system was automatically engaged"
I thought the 'flight protection system' was already engaged. Why would dual imputs trigger the ' flight protection system'
“The initial recovery from the dive was the result of the aircraft’s own protection measures, and not the product of pilot inputs.”
What exactly did the computer do to initiate 'initial recovery'?
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> The link I posted is the only good technical summary Agreed, except for... > Its automatic high-speed protection system was triggered 3s later, with a maximum indicated air speed of 358kt (662km/h), or Mach 0.9, recorded.
There is another thread on exactly what you've perceived as an error, because that statement is, in fact, accurate, counterintuitive to a physics education.