Spin recovery / runway drift / braking
Thread Starter
Join Date: Jun 2005
Location: London
Posts: 390
Likes: 0
Received 0 Likes
on
0 Posts
Spin recovery / runway drift / braking
Hi all,
Have a few questions that I am told have been asked recently by an interviewer I am about to face (first FO job). Help much appreciated!
1) What is the correct recovery for getting a 737 our of a spin? Does it apply to most commercial jets? Is it the same as piston singles? Or would you rip the rudder off?
2) If the RW is known to be slippery and you start drifting on the landing roll, do you just use rudder to correct? Brakes? Differential thrust?
3) What is the most effective way to brake on landing? My answer would be thrust reversers at first, then brakes become more effective as you slow down.
Thank you!!!
P
Have a few questions that I am told have been asked recently by an interviewer I am about to face (first FO job). Help much appreciated!
1) What is the correct recovery for getting a 737 our of a spin? Does it apply to most commercial jets? Is it the same as piston singles? Or would you rip the rudder off?
2) If the RW is known to be slippery and you start drifting on the landing roll, do you just use rudder to correct? Brakes? Differential thrust?
3) What is the most effective way to brake on landing? My answer would be thrust reversers at first, then brakes become more effective as you slow down.
Thank you!!!
P
Join Date: Jun 2005
Location: NY
Posts: 278
Likes: 0
Received 0 Likes
on
0 Posts
Since a spin is low airspeed manoeuver recovery therefore rudder should be just fine, in most jets spin recovery is ALMOST the same as piston except you don't reduce power because of the attendant trim changes etc confounding everything...1. center ailerons 2. opposite rudder against the turn HSI/ RMI. 3. yoke forward to gain airspeed. 4. Carefully, pullout subsequent dive; so it's ARE vs PARE. For a spiral dive level roll attitude on ailerons only the carefully pull from the dive again, leave power alone, reducing power in this case can lower the nose...not good!
ECON cruise, LR cruise...
Join Date: Apr 2002
Location: MIRSI hold - give or take...
Age: 52
Posts: 568
Likes: 0
Received 0 Likes
on
0 Posts
rhovsqared,
interwiev appers to centering on 73' - now, why wouldn't you reduce thrust? Afaik, that induces a pitch-down-moment???
Now, if you talked about not reducing thrust on the in-spin engine I might understand...
Empty
Edited to add my 2 kroners worth on 2 (rudder & cancel reverse thrust if any being used!) and 3 (spot on in my book...)
interwiev appers to centering on 73' - now, why wouldn't you reduce thrust? Afaik, that induces a pitch-down-moment???
Now, if you talked about not reducing thrust on the in-spin engine I might understand...
Empty
Edited to add my 2 kroners worth on 2 (rudder & cancel reverse thrust if any being used!) and 3 (spot on in my book...)
Last edited by Empty Cruise; 6th Mar 2006 at 18:44.
Thread Starter
Join Date: Jun 2005
Location: London
Posts: 390
Likes: 0
Received 0 Likes
on
0 Posts
Thanks Empty Cruise.
After Googling for a while, it looks like differential braking should be used if rudder does not do the trick if you're starting to skid away from the centerline (makes sense at lower speeds). Definitely not tiller though!
And as for braking/reverse thrust, I found a Flight Safety study that shows that thrust reversers decrease braking distance by about 15%. Not as much as I thought. I guess the majority of that 15% is in the first few seconds after touchdown.
P
After Googling for a while, it looks like differential braking should be used if rudder does not do the trick if you're starting to skid away from the centerline (makes sense at lower speeds). Definitely not tiller though!
And as for braking/reverse thrust, I found a Flight Safety study that shows that thrust reversers decrease braking distance by about 15%. Not as much as I thought. I guess the majority of that 15% is in the first few seconds after touchdown.
P
Join Date: Apr 2005
Location: Southeast USA
Posts: 801
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Permafrost_ATPL
Hi all,
2) If the RW is known to be slippery and you start drifting on the landing roll, do you just use rudder to correct? Brakes? Differential thrust?
3) What is the most effective way to brake on landing? My answer would be thrust reversers at first, then brakes become more effective as you slow down.
2) If the RW is known to be slippery and you start drifting on the landing roll, do you just use rudder to correct? Brakes? Differential thrust?
3) What is the most effective way to brake on landing? My answer would be thrust reversers at first, then brakes become more effective as you slow down.
Your other question is a bit mirkey ... the "most effective" braking is full brakes, maximum brake pedal deflection, as soon as the wheels are on the ground! Spoilers do help transfer weight to the wheels -- and they provide a modicum of additional form drag. Will you get hot (or warm) brakes doing this? Sure! But that IS the most "effective use" of brakes - changing kinetic energy into heat energy. Reverse thrust does help -- but it is far more effective at the higher airspeeds as has been said here a couple of times. On the other hand, if you're looking for the most cost effective use of the available methods to get the airplane stopped -- that is a different story. Assuming you have sufficient runway, spoilers as soon as you can (I prefer to wait until the airplane is on the ground -- or it will be soon), reverse thrust as soon as you can, and as much as you can - lessening the amount of reverse thrust as the forward speed slows (not doing much good and it avoids compressor stalls), and the judicious use of wheel brakes after reaching something below 100 knots.
Join Date: Mar 2006
Location: UK
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Permafrost_ATPL
And as for braking/reverse thrust, I found a Flight Safety study that shows that thrust reversers decrease braking distance by about 15%. Not as much as I thought. I guess the majority of that 15% is in the first few seconds after touchdown.
P
P
