A hasty go-around. Easy to be wise after the event
https://www.skybrary.aero/index.php/...no_Italy,_2008
Sometimes a hasty decision works out OK. Other times it doesn't. This is one occasion when a hasty decision (startle effect is the new buzzword) was wrong. Being wise after the event is another way of looking at it. |
Present level of flight safety to some extent is the result of being wise after events so there absolutely nothing wrong with that. If pilots were to learn everything from their own experience they may not live that long. By all accounts the decision to go around at less than 136ft because of birds was without any thought process involved. Call it startle or whatever it goes without saying was inappropriate, even if it would have worked. A slight delay in hitting TOGA would have brought them flare height. It was like reject takeoff after V1. It
can happen lucky to get away. So below certain height if stabilized there has to be a predetermination to land without thinking. |
Originally Posted by vilas
(Post 10563047)
Present level of flight safety to some extent is the result of being wise after events so there absolutely nothing wrong with that. If pilots were to learn everything from their own experience they may not live that long. By all accounts the decision to go around at less than 136ft because of birds was without any thought process involved. Call it startle or whatever it goes without saying was inappropriate, even if it would have worked. A slight delay in hitting TOGA would have brought them flare height. It was like reject takeoff after V1. It
can happen lucky to get away. So below certain height if stabilized there has to be a predetermination to land without thinking. |
Originally Posted by semmern
(Post 10563062)
Really? What about a CAT III a/p failure in the flare? |
A slight delay in hitting TOGA would have brought them flare height. It was like reject takeoff after V1. The guidance mentioned in the report "Birdstrike Threat Awareness" says, "VII.2 At Landing • On short final, do not go around, if birds are encountered, but fly through the bird flock and land. Try to maintain a low thrust setting. • The use of reverse thrust on landing after a birdstrike should be avoided. It may increase engine damage, especially when engine vibration or high EGT are indicated." Pity - that crew hadn't read it. |
Bear in mind this was from 2008 and there have been many advances in the technical and HP&L arenas since then.
There you are on short finals as captain and PM and you see a massive (>1,000 according to the report) flock of birds. After you’ve made the decision to avoid them, communicated it to the PF (who hasn’t seen them), the PF has overcome his startle reaction and commenced a GA, you fly into it. Shortly after, both engines suffer severe damage making a descent and landing the only option. This is an unpleasant situation to be in, not least because of the multiple reversals of intent over a short timescale: first landing, then GA, then forced landing. Coordinating something like that is a tricky CRM problem which doesn’t get practiced much, if at all, so it is no surprise that it went a bit pear shaped. That said, the aircraft got a bit bent but everyone inside lived, which for a double engine failure could be said to be a good result. Yes, you could argue that there might have been a better result if the captain (or FO, had he been PM in a similar situation) had immediately taken control and gone around, then informed the other pilot why but guidance on bird encounters only came out *after* this event. The accident was severe enough to trigger thorough investigation from all angles, leading to improved/new procedures and training but not so severe as to seriously injure or kill anyone. One might actually call that progress. Pity - that crew hadn't read it. |
Interesting read. How signifiant is it that they had switched off A/T, AP and FD? Would an Airbus 'alpha floor' type of protection have prevented the stall and flop and resulted in a more controlled return to earth after the odd decision to attempt a go around with engines full of dead birds ?
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Alpha floor is an auto thrust function (but does not require AT to be active). If you fly through a bunch of birds and the engines flame out, alpha floor will do nothing for you. |
Hi FullWings,
but guidance on bird encounters only came out *after* this event. https://skybrary.aero/bookshelf/books/181.pdf |
Yes but they were in a 737...
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Originally Posted by AerocatS2A
(Post 10563178)
Alpha floor is an auto thrust function (but does not require AT to be active). If you fly through a bunch of birds and the engines flame out, alpha floor will do nothing for you. |
Originally Posted by vilas
(Post 10563047)
Present level of flight safety to some extent is the result of being wise after events so there absolutely nothing wrong with that. If pilots were to learn everything from their own experience they may not live that long. By all accounts the decision to go around at less than 136ft because of birds was without any thought process involved. Call it startle or whatever it goes without saying was inappropriate, even if it would have worked. A slight delay in hitting TOGA would have brought them flare height. It was like reject takeoff after V1. It
can happen lucky to get away. So below certain height if stabilized there has to be a predetermination to land without thinking. |
Originally Posted by double_barrel
(Post 10563189)
Ah. I had misunderstood, thought it gave you full power but also limited AoA to give steepest possible climb.
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Originally Posted by Goldenrivett
(Post 10563144)
I disagree. It's nothing like rejecting take off after V1 - it is a recognised procedure called "Balked Landing".
The guidance mentioned in the report "Birdstrike Threat Awareness" says, "VII.2 At Landing • On short final, do not go around, if birds are encountered, but fly through the bird flock and land. Try to maintain a low thrust setting. • The use of reverse thrust on landing after a birdstrike should be avoided. It may increase engine damage, especially when engine vibration or high EGT are indicated." Pity - that crew hadn't read it. |
Originally Posted by ironbutt57
(Post 10563237)
it does, but cannot do so IF THE ENGINES ARE FLAMED OUT
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Angle of attack protections are different from alpha floor. Airbus type flight protections will go some way toward ensuring that the crash is controlled rather than fully stalled. |
See AF276 at Habsheim...
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Originally Posted by AerocatS2A
(Post 10563273)
Angle of attack protections are different from alpha floor. Airbus type flight protections will go some way toward ensuring that the crash is controlled rather than fully stalled. |
Originally Posted by vilas
(Post 10563299)
With engines flamed out in alternate law there is no alpha floor or AoA protection if you pull up you will be in full stall.
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Originally Posted by vilas
(Post 10563092)
Isn't your question superfluous? Just because you would go around in CAT3 with Flare mode failure you would like to go around in visual with a flock of birds at 100ft? I can only hope I am not among passengers.
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