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Landing Flaps request

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Landing Flaps request

Old 19th Feb 2021, 16:14
  #41 (permalink)  
 
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Originally Posted by vilas View Post
I am sorry but I totally disagree with you.
When I read your message I think we agree more than you think. Read again, every word this time. You almost repeat my words but write them in a different way.

However I've also seen more than enough people lost in the sky following SOPs blindly. I think many of us have. That's what I mean with situational awareness. You need time to create the "picture", and you do that on your own. There are no SOPs for that. It is you looking at your instruments.

Last edited by BraceBrace; 19th Feb 2021 at 16:24.
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Old 20th Feb 2021, 04:21
  #42 (permalink)  
 
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Brace Brace Let's leave our credentials alone. because that or thickness of logbook alone does not necessarily ensure that somebody is correct. On the issue of SOP and individual practices I will give you an example. In airbus when you are given a heading or you want to turn you can set heading and pull to get in HDG mode or you can first pull to get in HDG mode(or check HDG on FMA) and and then set heading. I see people doing either way. But SOP wants you to pull first. Is it splitting hair?
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Old 20th Feb 2021, 05:15
  #43 (permalink)  
 
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Centaurs
After all you don't say "Speed checked" when the landing gear is selected up or down
What are the occassions when gear is lowered first or raised risking speed excursions? I can think of only one, in EMER DES with damage gear is lowered to increase descent or having lowered raise it after level off. It's strictly an emergency procedure not even once in a life time event. Most pilots continue to retire without having ever done an EMER DES in real life or if you happen to meet one then he perhaps didn't need to lower the gear. So your example is not appropriate. As against this routinely, daily flap is the first thing to be lowered and exceedences do occur. Second why should copilot even check silently isn't Capt more experienced and is supposed to check that speed is appropriate? In the air humans have limitations and they forget so speed checked call is a forced reminder. If everybody did what they are supposed then we won't be discussing it. People have forgotten gear for entire flight, have raised flaps instead of gear, landed without gear, have lowered flaps high speed, have exceeded speed after lowering causing auto retraction. The list is endless. No caution is enough. It's better to be more than less.
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Old 20th Feb 2021, 05:45
  #44 (permalink)  
 
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On some Boeings, the flap will trigger the GPWS Mode IV, and it won't be cancellable. As stated, depends if the flap is defined as a landing flap config.
As everyone is aware principally uncancellable warning should not cancelled unless it's false. In this case when under pressure one could be setting himself up for a gear up landing.
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Old 20th Feb 2021, 08:23
  #45 (permalink)  
 
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Originally Posted by vilas View Post
What are the occassions when gear is lowered first or raised risking speed excursions?
I've done this on numerous occasions at a certain airport where there is no coordination between center and approach. Busy airport (read freight with sudden peak times at night), you expect to be n° 5 or 6 center, 250kts already... but center suddenly gives you direct 10 miles final and makes you n°1. Below 10000ft, speedbrakes don't cut it, out comes the gear. Then approach decides otherwise again as it's not working, and you are number 5 again...

On your question of Airbus HDG. I refrain from any technical answer. But from a psychological point of view, if the flying pilot on AP likes to preset the heading while the readback is done as a mental backup, I don't see any problem as the SOP is correctly handled. It's just that the heading bug is already preset. But then again, I don't know any technical background that would post a limitation on this behaviour. Because that is what you seem to imply, the SOP is related to a limitation of the autoflight system somehow.
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Old 20th Feb 2021, 09:37
  #46 (permalink)  
 
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All over the world below 10000ft you have to 250kt. So what's the problem lowering gear? You don't need to check. About the Airbus heading, there's no system limitation but not following SOP of pulling HDG first and then setting has resulted in a fatal accident of AirBlue in Pakistan. Out of many things wrong they did dialling in NAV mode was the last straw. In a circling approach Capt was in panick in low clouds and rain. Trying to turn base on AP he dialed 90° left, seeing ac not turning dialled some more to go past 180° from present. Then realising he was in NAV mode (shouldn't have been to start with) letting go some expletives pulled to HDG mode. The aircraft turned shorter way to right to crash into a hill. Killing all 150 people on board. All of his 20000hrs thick logbook didn't save him. SOPs are not optional. Human propensity to err is virtually unlimited. Cockpit is hardly the place to be creative. QZ8501 trying to engineer a procedure at 35000ft all the zeros over 3 vanished 3.5mts and 130 people went to watery grave. Just Fly the way manufacturer wants you to fly unless there's no procedure. It happened in AB erroneous triggering of protection and air craft could not be prevented from a descent. Now crew was forced to do something and they put the aircraft in alternate law to disengage the protection. My hats off to them. There was one odd case of this but when they made it a possible procedure for such scenario there were dozen cases of wrong application when problem was something else. Doesn't help trying to be extra smart.

Last edited by vilas; 20th Feb 2021 at 09:50.
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Old 20th Feb 2021, 10:44
  #47 (permalink)  
 
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Originally Posted by vilas View Post
.........In airbus when you are given a heading or you want to turn you can set heading and pull to get in HDG mode or you can first pull to get in HDG mode............I see people doing either way. But SOP wants you to pull first. Is it splitting hair?
You have answered your own question in a later post, but as you know; on Airbus FBW if you select more than a 180° change and then pull HDG, the aircraft might turn the wrong way - it calculates shortest turn to the new HDG. Therefore the SOP is to pull HDG knob first before changing the heading, to ensure the aircraft turns in the direction you want.

Did they change this software in later models?

On the OP question; there are rare occasions when ATC cut you in closer than you expected or asked you to keep the speed up, when I might ask: "Flap x as soon as you can", and we both understand that means when the speed has dropped suitably below Vfe next.
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Old 20th Feb 2021, 11:36
  #48 (permalink)  
 
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THe call out for Pull HDG hasn't changed. I was trying to say it may appear there are two ways of doing a thing but only the one recommended by SOP must be followed. Below 10000ft gear can be lowered without much caution. I think B737 gear lowering speed is 270kt. If tighter vectoring You can always use speed brake, below VLO gear, below VFE first flap then put speed brake in, continue configuring all the way. There's still time to say speed checked. Actually more so because this is the time you may drop your guard.
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Old 20th Feb 2021, 12:02
  #49 (permalink)  
 
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Originally Posted by Uplinker View Post
On the OP question; there are rare occasions when ATC cut you in closer than you expected or asked you to keep the speed up, when I might ask: "Flap x as soon as you can", and we both understand that means when the speed has dropped suitably below Vfe next.
By doing so, you are eliminating the cross-check as a safety layer, and allowing another hole in the swiss cheese model to line up.

PF should check whether the conditions allow for configuration change, call for it, PM should check the same conditions, then action the change. Callouts or not.
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Old 20th Feb 2021, 13:18
  #50 (permalink)  
 
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Yes, absolutely. In those (rare) situations* I still monitored the speed and PM. It was when I was close to or rapidly approaching Vfe next, and I knew there was about to be a radio call so I would have had to speak over ATC or PM's reply, so I got my config request in just ahead of that. Not something we routinely had to do.

*At our home base; owing to airspace below and traffic, the ILS intercept could be close in and busy, and if you didn't act quick enough, you then had to intercept the glide from above.

Last edited by Uplinker; 20th Feb 2021 at 13:28.
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Old 20th Feb 2021, 17:47
  #51 (permalink)  
 
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vilas

Again, you haven't read my post so what is the point of this discussion?

The gear limit always has to be checked before lowering/raising the gear every single time. If you train people to the standard "you don't need to check", I close my books and leave this discussion. If you read my post, it explains raising the gear after having descended with 250kts. There is a speed limit.

Your crash story: I don't understand your reasoning. Yes you have to adhere to the SOP. But you do realise the "no crash, no problem" idea?The underlying training issue here is still there: no APFD behaviour monitoring for whatever reason, not monitoring of the actual outcome. Any crash comes with SOP changes AND training. The SOP in itself is not the full cause, a change in SOP not the full cure and not the full protection. SOPs are a tool with different goals (crm is part of it yes), Autopilots are a tool, Flight Director is a tool, and all those tools help to reach a safe goal. But if you notice that goal is not being achieved, you act. SOPs are not bulletproof.

The supplementary procedure on a Boeing, where HDG SEL shows the exact same behaviour as on the Airbus, is to rotate the heading bug, then select HDG SEL. But it also says "VERIFY FMA". And then you verify the AP action. And it does not do what you want it to do? You disconnect and turn in manual flight. All Boeing procedure written down in the manuals. There is not a single SOP violation in this full paragraph for a system that functions identical.

Anyway, I'm out.

Last edited by BraceBrace; 21st Feb 2021 at 08:48.
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Old 21st Feb 2021, 13:25
  #52 (permalink)  
 
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Originally Posted by Uplinker View Post

On the OP question; there are rare occasions when ATC cut you in closer than you expected or asked you to keep the speed up, when I might ask: "Flap x as soon as you can", and we both understand that means when the speed has dropped suitably below Vfe next.
I can’t see a reason in a normal situation for a conditional request for a configuration change. I may have missed it, but I haven’t read anywhere where that is even a thing considered.
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Old 22nd Feb 2021, 05:42
  #53 (permalink)  
 
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On the OP question; there are rare occasions when ATC cut you in closer than you expected or asked you to keep the speed up, when I might ask: "Flap x as soon as you can", and we both understand that means when the speed has dropped suitably below Vfe next.
I cannot imagine such urgency in normal flight that the PF doesn't have even the few seconds to glance at the speed and utter "Flap X". Just because PM is supposed to call speed checked doesn't mean PF can order flap at any speed. It's a double check. Airbus even shows you Vfe next. This all non-standard and unjustifiable. ATC will tell you no speed restrictions you have to go managed speed it may take time for speed to reduce. You cannot write a blank cheque. Look! There's only so much distance within which you can do things properly. Anything more tight you must refuse the speed restriction or try your luck and go around. There are only standard call outs, no non-standard call outs.
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Old 22nd Feb 2021, 13:34
  #54 (permalink)  
 
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Check post #50?

You are misrepresenting what actually happened and maybe I haven't explained it very well, but I have a garage to paint, so I am not going into the whole thing now - you would have to have been there. My base manager was in the other seat and was perfectly happy with the situation.

As I've said, (twice); it was not normal

Last edited by Uplinker; 22nd Feb 2021 at 13:45.
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Old 21st Mar 2021, 00:00
  #55 (permalink)  
 
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Saying things like "speed checked" or avoiding actuating multiple hydraulic devices simultaneously, should be based on the company's SOP regardless of whether we find it superfluous. (Happily for me, neither is a part of my airline.)

But if a certain sequence of actions sets off a gear horn, then IMO airmanship requires we don't do that. At best, it's very annoying, and at worst, it conditions our brains to ignore it as a meaningless sound that falls to the background in normal ops, and therefore makes it likelier to ignore if we get a real gear horn with the gear up. (The cries wolf effect.)

Also, generally, the PF shouldn't call for actions before they can be done. It sets up the PM to forget by the time 10 or 20 seconds have rolled around and the conditions are met, and other distractions have gotten in the way. It's the PF being out of the loop, and unfairly burdening the PM. The PF should stay in the loop and call for the thing when he actually wants it. Don't have any more balls in the air than necessary.

Thirdly, it is very possible that for a combination of circumstances to render the strict following of SOP to be inappropriate, as it's impractical to write a manual that can consider every single possibility - and judgment should therefore be used. And the preface to my SOP chapter, says exactly this. However, all too often I see this used as cheap justification for being lazy, instead of actual good judgment.
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