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Edelweiss almost touches down again immediately after lift-off
Well, they had to, given other decisions that were made: make the pass at V-alpha-prot. That was never going to work with Alpha floor active.
So for me the real question is who's bright idea was to palan the pass at V-alpha-prot.
They could have decided to do the pass at VLS instead. Then:
- They wouldn't have needed to disable Alpha floor.
- They could have done the pass on autothrottle which would have avoided the inadvertent loss of speed below the target speed.
- They would have had more energy margin overall (for example, to pull up to avoid trees).
- The pass would have been just slightly less impressive, the difference was not worth the risk (yeah, I know, hindsight).
I think it was because it is inhibited below; 100ft you don't want the warning during the flare. Also at some point (too late) they firewalled the thrust lever which also inhibits the warning because you already took the corrective measure.
Maybe, but even with no Alpha Floor and no low energy warning, having a hard AoA protection is better than not having it, as this accident proved.
What does 3BS want to know?
Whose idea it was to not_watch the airspeed? I’m telling you, that crap is important, especially when you are close to the ground…Hui Theiu Lo, Ho Lee Phouc.
Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.
What does 3BS want to know? Whose idea it was to not_watch the airspeed?
Nobody's. That was not intended. Unlike the other crazy things they did which were intentional and hence somebody's idea.
--- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
--- Defend what you say with arguments, not by imposing your credentials ---
Well, some protections did not work at all in that accident.
I know that Alpha Floor was intentionally inhibited, but as Evan pointed out, it's automatically inhibited below 100ft. So I was puzzled concerning other ones I didn't know about.
Alpha Prot is always working and can't be disabled. During a normal landing, you definitely don't want Alpha Floor to kick in at e.g. 10ft due to a gust.
Most likely Airbus estimates that a hard landing at max AoA is less dangerous than the severe pitch up caused by the very low speed / max thrust combination and a likely tailstrike due to an 'automatic' unintentional go-around.
I know that Alpha Floor was intentionally inhibited, but as Evan pointed out, it's automatically inhibited below 100ft. So I was puzzled concerning other ones I didn't know about.
Alpha Prot is always working and can't be disabled. During a normal landing, you definitely don't want Alpha Floor to kick in at e.g. 10ft due to a gust.
Most likely Airbus estimates that a hard landing at max AoA is less dangerous than the severe pitch up caused by the very low speed / max thrust combination and a likely tailstrike due to an 'automatic' unintentional go-around.
Yes, but more to the point, Airbus estimates that any pilot who is granted a CTPL is reliably capable of getting down safely without Alpha Floor from 100ft (which assumes visual) in manual flight. Those protections are second line of defense intended for more stall-prone situations. It was not designed for level fly-by’s near Alpha Max below that threshold. It is not designed to be idiot-proof.
This accident flight came right to the edge of Flare mode, the 30ft threshold, where a nose down order is added by the computers, but fortunately remained just above it.
This accident flight came right to the edge of Flare mode, the 30ft threshold, where a nose down order is added by the computers, but fortunately remained just above it.
I am not sure if it would have not made a difference since the pilot was pulling fully back anyway. This nose down command (to simulate what happens in non-FBW plane when entering in ground effect, and to stimulate the pilot to pull up to flare) is jut a bias, not a "hard input" (i.e. not like alpha max) so it can be overridden with control inputs.
--- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
--- Defend what you say with arguments, not by imposing your credentials ---
Only partially. At 30ft the flare mode commands a pitch down rate to reach a pitch attitude of -2° within 8sec. This results in interesting different flare behaviour IRL.
If you are considerable faster the your target speed, the pitch down is almost not noticeable and need only minimal aft stick input.
If you are on the other hand below your target speed, the pitch down is pretty violent and you can just barely counter the nose down command with full aft stick.
Only partially. At 30ft the flare mode commands a pitch down rate to reach a pitch attitude of -2° within 8sec. This results in interesting different flare behaviour IRL.
If you are considerable faster the your target speed, the pitch down is almost not noticeable and need only minimal aft stick input.
If you are on the other hand below your target speed, the pitch down is pretty violent and you can just barely counter the nose down command with full aft stick.
This is not directed at Bert, but the entire conversation. That damn that “plane” is always monkeying with pilots inputs… whoops, I need some extra flare…I’m sorry, Bert, additional elevator input is not available when in flare mode C-14blo100frrdalt on Wednesdays between 1400 and 2400Z.
Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.
This is not directed at Bert, but the entire conversation. That damn that “plane” is always monkeying with pilots inputs… whoops, I need some extra flare…I’m sorry, Bert, additional elevator input is not available when in flare mode C-14blo100frrdalt on Wednesdays between 1400 and 2400Z.
And, for the record, there have been some notable incidents of pilots monkeying with the plane. Including some monkey see, monkey do. AIrbus did not include monkey-proofing in the design spec, regrettably.
Before I watch it.. Is it true os is it one of those conspiracy theories?
--- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
--- Defend what you say with arguments, not by imposing your credentials ---
Before I watch it.. Is it true os is it one of those conspiracy theories?
Did you forget the blue font Gabe?
Answer: it depends. If the film points out the fatal logic in continuing an unstable tailwind approach and touching down 2500ft past threshold at 170kts, then yes, it’s true. If the film deals in scarebus conspiracy, then what was I just saying about monkeys?
Airbus did get the film banned, for very good reason. Unfortunately we live in an age where certain enterprising charlatans seek opportunity in freedom of speech to profit from nonsense and paranoia. So it is now available again. If you enjoyed this, I would also recommend 9/11 was an inside job, flat earth society and RFK jr.
Hm, I don't know a single Airbus pilot who disagrees with this documentary. It's very well researched and even top Airbus staff admits that Airbus was a horrible, arrogant and high-handed company.
The Warsaw accident is a perfect example how Airbus was back in these days.
Hm, I don't know a single Airbus pilot who disagrees with this documentary. It's very well researched and even top Airbus staff admits that Airbus was a horrible, arrogant and high-handed company.
The Warsaw accident is a perfect example how Airbus was back in these days.
Evan, who is not_a pilot, thinks all pilots are stupid and that Airbus is perfect.
Ok, I exaggerated a little.
I watched the movie, and thought it made some interesting points. Sure, there’s a counter argument that it’s easier to criticize than it is design airplanes, and the counter counter argument that companies will spin things to make themselves look good.
There was an interesting MCAS-like story of pilots not_being told that an unlevel landing would make it totally impossible to deploy the spoilers, but Evan has spoken, and that was the stupid cowboy monkey pilots’ fault.
Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.
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