aerodynamic braking
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Isn't there some sort of concern with regards the elevators running out of sufficient authority to smoothly lower the nose, or a horizontal stabiliser stall, leading to slapping the nose down?
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When conducting training, I impart that there are two landings made... the main gear and then the nose gear. That said after touchdown, its important to prevent the nose wheel from slamming onto the ground with the proper use of back pressure from not allowing pitch attitude to increase.
Last edited by captjns; 28th May 2013 at 02:35.
The only time aerodynamic braking should be employed on large aircraft.
I seem to recall a 737 accidnt in the US where the last words of the PF before the aircraft ran off the end of the runway were "I'll show you how we used to stop the F4".
I seem to recall a 737 accidnt in the US where the last words of the PF before the aircraft ran off the end of the runway were "I'll show you how we used to stop the F4".
There is no such thing as aero dynamic breaking.
There might, of course be aerodynamic braking.............
We used to think this worked quite well.......
Last edited by Lightning Mate; 29th May 2013 at 08:07.
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We do this quite often in heavy aircraft flight test when landing above the brake energy limit, on a long runway, and have no desire to activate the fuse plugs.
The trick is:
Touchdown
Deploy spoilers
Increase pitch attitude to maximum that provides margin from tail strike, say 2 degs less
Derotate before elevator loses effect or runway running out...
Brake
From my notes, around a 1-2kt/sec decel was possible which makes a significant effect on brake energy (much lower due to the v squareds being less)
The trick is:
Touchdown
Deploy spoilers
Increase pitch attitude to maximum that provides margin from tail strike, say 2 degs less
Derotate before elevator loses effect or runway running out...
Brake
From my notes, around a 1-2kt/sec decel was possible which makes a significant effect on brake energy (much lower due to the v squareds being less)
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Even a barbie jet can use up quite a bit of runway 
He probably had around 3800 metres to play with ,and it is a looong taxi after that to the terminal,even so looks like 1000+ metres before the nosewheel 'touched down'.
He probably had around 3800 metres to play with ,and it is a looong taxi after that to the terminal,even so looks like 1000+ metres before the nosewheel 'touched down'.
Last edited by camel; 30th May 2013 at 12:46.
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Hi... Nobody has mentioned CofG. For the Broken Nose-Wheel video, if he had moved all the Pax to the rear of the cabin he might have even been able to taxi to the gate with the front in the air !
(Quite what would happen when the first pax steps out is another matter.)
(Quite what would happen when the first pax steps out is another matter.)
Jaguar Photo
LM,
Great photo. A couple of questions if I may. Did such a high nose attitude delay the full opening of the dragchute due to any disrupted airflow or blanking effect? Was there any significant nose-down trim change when it fully deployed? Just curious, thanks.
Great photo. A couple of questions if I may. Did such a high nose attitude delay the full opening of the dragchute due to any disrupted airflow or blanking effect? Was there any significant nose-down trim change when it fully deployed? Just curious, thanks.
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We do this quite often in heavy aircraft flight test when landing above the brake energy limit, on a long runway, and have no desire to activate the fuse plugs.
The trick is:
Touchdown
Deploy spoilers
Increase pitch attitude to maximum that provides margin from tail strike, say 2 degs less
Derotate before elevator loses effect or runway running out...
Brake
From my notes, around a 1-2kt/sec decel was possible which makes a significant effect on brake energy (much lower due to the v squareds being less)
The trick is:
Touchdown
Deploy spoilers
Increase pitch attitude to maximum that provides margin from tail strike, say 2 degs less
Derotate before elevator loses effect or runway running out...
Brake
From my notes, around a 1-2kt/sec decel was possible which makes a significant effect on brake energy (much lower due to the v squareds being less)
If the runway is 4,000m long, your parking spot is at the departure end, all systems are working normally, minimal cross wind, good weather, dry runway, headwind, 747-200F with brakes that tend to get hot (especially landing in the middle east when it's 45C+ outside), competent and experienced flight crew, it is not a big deal. Revers to Idle, get 4 green, add more reverse thrust. It is the difference between parking with brake temps in the amber range or brake temps in the red range. I'm not talking about running the stab trim all the way aft during rollout and trying to get every last bit of elevator authority out of the beast. Having said that, now that I am on the 744 with the carbon brakes I no longer do that procedure nor do the crews I fly with, it is not needed on the 744. Know your airplane, do some of that pilot stuff! Hundred landings in the middle east and never blew a fuse plug, but we would have 1 or 2 crews a year that did. Maybe I was just lucky!
Fire Away
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Just from curiosity -
I looked up KC-135 landings on Youtube, and couldn't find any aero braking examples. That's not to say it's never done, but probably not encouraged.
I looked up KC-135 landings on Youtube, and couldn't find any aero braking examples. That's not to say it's never done, but probably not encouraged.
Barit1
At least in my part of the USAF, we were taught to put all the paws on the pavement for both braking effectiveness and directional control. And do so BEFORE going beyond reverse idle in case spool up was uneven.
GF
At least in my part of the USAF, we were taught to put all the paws on the pavement for both braking effectiveness and directional control. And do so BEFORE going beyond reverse idle in case spool up was uneven.
GF
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Breaking vs braking
Hi
You got it Mate ( lightning),
If you want to finish your linecheck with a bang, tail stike or not, demontrate your skills to your f/o and the lineckr. And voila , you are breaking new ground in the training department. Or not.....?
With regarde to milatary aviation I know nil so I see the point of draging up. ( still not aerodynamic brkn!)
Usefull if you have no brakes, wich I did not have on a regulare bases flying in Ontario in a vee little Cessna 185 on ski and floats...... RTOW and LDA etc was ..... Up to you and your ac.
Lastly as to why we are having this discussion, ?
Live and learn, in the 1980s we did not have internet accses, on pprune, so I read all the reports that Transport Canada published.,with special curiousity about what NOT to do with a Cessna.Useful, still alive!
Back to the future, Boeing and Airbus specificaly states : Dont think about it!
Grounded 27 , we need to go flying together one day!!?
Cheers
Blusdup and out!
You got it Mate ( lightning),
If you want to finish your linecheck with a bang, tail stike or not, demontrate your skills to your f/o and the lineckr. And voila , you are breaking new ground in the training department. Or not.....?
With regarde to milatary aviation I know nil so I see the point of draging up. ( still not aerodynamic brkn!)
Usefull if you have no brakes, wich I did not have on a regulare bases flying in Ontario in a vee little Cessna 185 on ski and floats...... RTOW and LDA etc was ..... Up to you and your ac.
Lastly as to why we are having this discussion, ?
Live and learn, in the 1980s we did not have internet accses, on pprune, so I read all the reports that Transport Canada published.,with special curiousity about what NOT to do with a Cessna.Useful, still alive!
Back to the future, Boeing and Airbus specificaly states : Dont think about it!
Grounded 27 , we need to go flying together one day!!?
Cheers
Blusdup and out!
