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744 Eng Fail and Vmcg

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744 Eng Fail and Vmcg

Old 6th Jan 2021, 23:58
  #41 (permalink)  

Only half a speed-brake
 
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Yes, that is what tends to happen..Thank you for correcting.

Also now the stars align proper once again. Close call!
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Old 7th Jan 2021, 00:03
  #42 (permalink)  
 
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Heels should be on the floor for take off and on landing until initiating manual braking
I completely agree.

If (and it’s a really big if!) that means you go off the side of the runway on a low speed abort at 30 or 40 knots, that’s totally survivable. On the other hand, inadvertent (differential?) braking at higher speed is a very different scenario. Where do the greater adverse consequences lie?

Does any manufacturer recommend ‘feet up’ for take off? I’ve flown five different jet liners from three major manufacturers and I can’t recall it? Or is this just a ‘bright idea’?
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Old 7th Jan 2021, 00:03
  #43 (permalink)  

Only half a speed-brake
 
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Originally Posted by stilton View Post
Heels should be on the floor for take off and on landing until initiating manual braking
No such general rule. What do the test pilots do when measuring the ASD performance?

Airbus has a clear opinion of it. Proper modern pedals can be designed for a safe feet up takeoffs.
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Old 7th Jan 2021, 03:37
  #44 (permalink)  
 
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Originally Posted by stilton View Post
This again,

Are there any operators out there who encourage this dubious practice ?

Heels should be on the floor for take off and on landing until initiating manual braking
You are neither an operator nor a manufacturer so kindly quote a manufacturer recommendation to support your views.
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Old 7th Jan 2021, 05:24
  #45 (permalink)  
 
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Does any manufacturer recommend Ďfeet upí for take off? Iíve flown five different jet liners from three major manufacturers and I canít recall it? Or is this just a Ďbright ideaí?
4468 and stilton
I have also flown five airliners and three of them wide bodies including 747 but that doesn't mean anything. Everyone has his comfort blanket. FAA document Pilot Guide to Take off Safety in para 3.2.6.5 says the following:
"The pilotís foot position relative to the rudder pedal can also have an effect on the achievement off full brake pressure. It was noted during a study conducted by the Training Aid Working Group that foot position during the takeoff roll tends to be an individual preference. Some pilots prefer to have their feet "up on the pedalsĒ to be ready to apply full brakes if required. Pilots who prefer this technique also noted that their toes areďcurled backĒ to avoid unwanted brake applications when applying rudder. The other technique is to rest the heels on the floor during the takeoff roll, and then raise them to be on the pedal to apply full braking. No problems were noted with either technique."
on a slippery runway in 747 classic where nose wheel is not connected to the rudder if outer engine fails you cannot stop excursion unless rudder and differential braking is simultaneously applied. If you can do it with feet on ground then good for you.
as far as landing is concerned if you are an Airbus pilot then listen to Airbus Win APPROACH AND LANDING PROCEDURES AND TRAINING RECOMMENDATIONS. At about 7:47 he categorically stated "steer with heels and brake with toe."
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Old 7th Jan 2021, 09:52
  #46 (permalink)  
 
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How many 747 classics are still in operation worldwide? A non steerable nose wheel sounds about as relevant to this discussion as a non steerable tailwheel?

inadvertant (and unwanted) brake operation is not possible with heels on the floor. That’s where the greater consequences lie as the aircraft accelerates and/or up to full rudder may be required. (AFTER landing is of course a totally different situation!)

However we are all trained to apply our own braking during a rejected take-off at speeds below activation of RTO auto brake function. It’s not difficult to slide your feet up at low speed.

Thank you for confirming no manufacturer or regulator recommends your personally favoured technique for take off.

I believe there is a difference here between Boeing and Airbus? I have flown both products, though more B than A.

Last edited by 4468; 7th Jan 2021 at 10:08.
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Old 7th Jan 2021, 11:22
  #47 (permalink)  
 
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Thank you for confirming no manufacturer or regulator recommends your personally favoured technique for take off.
No manufacturer recommends keeping the heels on the floor either. In one of the Airbus training centres this question was asked and the pilots were using both techniques. Airbus doesn't have any preference. Actually the problem is well below V1 just after thrust is set. Closer to V1 rudders are effective and there's no problem.

Last edited by vilas; 7th Jan 2021 at 13:23.
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Old 7th Jan 2021, 13:58
  #48 (permalink)  
 
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I’m surprised to have to admit, I can’t find anywhere that ‘recommends’ heels on the floor! 😳

I’m also scratching my head to recall what I did during my 6 years on A319/320/321? The more I think about it, maybe I did fly those take offs with feet up???

But I’m absolutely certain I never did that in the many years spent on any of the three Boeing types I’ve flown! Nor on the other jetliner I flew. Maybe the difference is purely down to pedal design? Though even Airbus themselves express no specific recommendation.

However in general, my personal preference would be heels down, as I believe the greater consequence is inadvertent (differential?) braking at high speed, or inadvertent disabling of RTO autobrake extending the reject distance. (Both of which I have seen.) Presumably purely to combat a possible low speed runway excursion. All of the above being hypothetical of course.

I see this is a discussion you have been involved in previously.

As I said. My opinion only. Clearly not yours.

Last edited by 4468; 7th Jan 2021 at 15:49.
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Old 7th Jan 2021, 15:50
  #49 (permalink)  
 
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Originally Posted by 4468 View Post
Iím surprised to have to admit, I canít find anywhere that Ďrecommendsí heels on the floor! 😳

Iím also scratching my head to recall what I did during my 6 years on A319/320/321? The more I think about it, maybe I did fly those take offs with feet up???

But Iím absolutely certain I never did that in the many years spent on any of the three Boeing types Iíve flown! Nor on the other jetliner I flew. Maybe the difference is purely down to pedal design? Though even Airbus themselves express no specific recommendation.

However in general, my personal preference would be heels down, as I believe the greater consequence is inadvertent (differential?) braking at high speed, or inadvertent disabling of RTO autobrake extending the reject distance. (Both of which I have seen.) Purely to combat a low speed runway excursion. All of the above being hypothetical of course.

I see this is a discussion you have been involved in previously.
I am not rigid about it. One can be selective according to threat perception. There are two aspects. In a go decision it's slightly advantageous to have heels on the floor. With heel dug in the floor you can have precise rudder control( not needed in airbus). While in wet slippery conditions a low speed reject at full thrust with feet up it's very easy to just slam the appropriate rudder and brake. If the foot was on ground then instinctively you will apply rudder first then holding rudder slide the foot up to brake there can be a little delay. In normal conditions keep it on ground. And yes Airbus peddles have an edge all around the peddles, feet can be kept up. I have used both but none of them are my inventions.
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Old 7th Jan 2021, 16:42
  #50 (permalink)  
 
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4468 : I did the A330 course with Airbus at Toulouse in 1994 and then the instructors were of "the heels on the floor" method.
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Old 7th Jan 2021, 21:31
  #51 (permalink)  

Only half a speed-brake
 
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This
I’m surprised to have to admit, I can’t find anywhere that ‘recommends’ heels on the floor!
is very aptly responded with
Thank you for confirming no manufacturer or regulator recommends your personally favoured technique for take off.
Both copied from upthread. Topic closed, 3 weeks sooner compared to that other last time?
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Old 14th Jan 2021, 04:37
  #52 (permalink)  
 
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Boeing Chief Pilot of special projects Jerry Whites and Vmcg tests on the 747 Dreamlifter at 27:27. Interesting life test pilots, first time he stalled a 777 ended up inverted.

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Old 17th Jan 2021, 01:13
  #53 (permalink)  
 
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Originally Posted by 4468 View Post
Iím surprised to have to admit, I canít find anywhere that Ďrecommendsí heels on the floor! 😳

Iím also scratching my head to recall what I did during my 6 years on A319/320/321? The more I think about it, maybe I did fly those take offs with feet up???

But Iím absolutely certain I never did that in the many years spent on any of the three Boeing types Iíve flown! Nor on the other jetliner I flew. Maybe the difference is purely down to pedal design? Though even Airbus themselves express no specific recommendation.

However in general, my personal preference would be heels down, as I believe the greater consequence is inadvertent (differential?) braking at high speed, or inadvertent disabling of RTO autobrake extending the reject distance. (Both of which I have seen.) Presumably purely to combat a possible low speed runway excursion. All of the above being hypothetical of course.

I see this is a discussion you have been involved in previously.

As I said. My opinion only. Clearly not yours.
When you are doing your captain upgrade on the A320 in a company with a high candidate failure rate and they are giving you low speed engine failures, I suggest having the feet up. Then you can decide on the line what to do. Feet up gives nearly instant full rudder and differential brake allowing one to avoid an accident known as a runway excursion. Never had an engine failure on takeoff in real life, so I can't say if the sim is similar to the airplane. I like feet up.
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