Idle Reverse while vacating
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Does anyone here have an opinion with regard to keeping reversers at idle while vacating the runway after landing when the aircraft is still decelerating (i.e. entering the taxiway). Any possible risks associated with doing this?
Aside from all of the FOD risks noted above, this is an engine cycle that is counted for maintenance. Most airlines tend to want to reduce rev thrust cycles and time, to reduce maintenance cycles on the engines.
Brakes/replacement are far cheaper than engines.....
Yes, but more than one airline found that the money saved was negated by some order(s) of magnitude by having an aircraft off the end of the runway in the greenery.
Aircraft type doesn’t affect the issue too much here. One problem is that in winter with runway conditions reported, very often the turn off taxiways can be much more slippery.
Idle reverse until taxy speed (a very slow taxy speed) is a good idea.
Out in the sticks in summer FOD is the problem, so as long as she brakes OK, stow the reverse.
Idle reverse until taxy speed (a very slow taxy speed) is a good idea.
Out in the sticks in summer FOD is the problem, so as long as she brakes OK, stow the reverse.
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Aircraft type doesn’t affect the issue too much here. One problem is that in winter with runway conditions reported, very often the turn off taxiways can be much more slippery.
Idle reverse until taxy speed (a very slow taxy speed) is a good idea.
Out in the sticks in summer FOD is the problem, so as long as she brakes OK, stow the reverse.
Idle reverse until taxy speed (a very slow taxy speed) is a good idea.
Out in the sticks in summer FOD is the problem, so as long as she brakes OK, stow the reverse.
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That you'll be slowing to a safe speed before turning, is the type of obvious and unnecessary statement that we should not be clogging frequencies with. Like that we won't be taking off overweight or flying slower than stall speed. Duh.
ATC should know that planes have to slow down more for turns when it's slippery out; and if they don't, they'll figure it out quickly enough.
What is your airline SOP,?...rev thrust or braking?
Aside from all of the FOD risks noted above, this is an engine cycle that is counted for maintenance. Most airlines tend to want to reduce rev thrust cycles and time, to reduce maintenance cycles on the engines.
Brakes/replacement are far cheaper than engines.....
Aside from all of the FOD risks noted above, this is an engine cycle that is counted for maintenance. Most airlines tend to want to reduce rev thrust cycles and time, to reduce maintenance cycles on the engines.
Brakes/replacement are far cheaper than engines.....
If you respect the FCOM recommendations on reverser usage - getting them to idle by 60 knots, and stowing by taxi speed, the risk of re-ingestion and associated engine damage are minimal.
The key is to respect the FCOM recommendations - reverse below 60 knots doesn't do much aside from killing the forward idle thrust - so there is really no reason to use them unless getting the aircraft stopped in time is not a sure thing (in which case abusing the reversers is probably preferable to abusing the airframe).
aircraft type does affect the issue quite a bit. The lower the engines and the further they are mounted from the fuselage, the higher the effect of FOD. If its too slippery to be taking a RET at high speed then slow it right down on the runway before vacating. Just tell ATC about it.
In icy conditions you will use as much of the runway as necessary to decelerate and won’t be trying for an early exit.
If you are prepared by having the reverser in idle, you are in better shape to react to this not uncommon case - particularly if you are first landing after RW opening... The airport ties hard to keep/get the runway open and taxy ways come second.
Generally under such conditions there is less risk of stone ingestion, but snow can be blown loose.
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That you'll be slowing to a safe speed before turning, is the type of obvious and unnecessary statement that we should not be clogging frequencies with. Like that we won't be taking off overweight or flying slower than stall speed. Duh.
ATC should know that planes have to slow down more for turns when it's slippery out; and if they don't, they'll figure it out quickly enough.
ATC should know that planes have to slow down more for turns when it's slippery out; and if they don't, they'll figure it out quickly enough.
Get off your high Horse buddy. If you don’t have any thing constructive to add then I suggest you keep your negativity to yourself.
It is quite reasonable to advise ATC When they need you to expedite vacating. Or there is guidance in the AIP advising you to use a particular exit which you cannot make or requiring you to vacate within a number of seconds after landing (eg in china).
While training crews in Asia who were used to their company procedures (not necessarily Boeing FCTM procedures), it was noticed they tended to completely cancel reverse thrust at the 60 knots call during the landing run. At the call of 60 knots, they would slam the reverse thrust levers fully down from full reverse (Boeing 737). This would cause the aircraft to momentarily accelerate down the runway while the pilot was still also applying the brakes. The reason being the N1 would be still running down through around 60% N1 when the reverser lights went out; thus giving momentarily significant forward thrust.
It wasn't until the English second language pilots were advised to carefully read (and understand) the FCTM instructions about the need to allow the N1 to reach idle reverse before cancelling, that the penny dropped they were doing it all wrong.
It got me thinking about landing with loss of all hydraulic braking capability - rare though that possibility could be, of course. The scenario in the simulator was concerned with the use of reverse thrust and the aircraft managing to stop still in full reverse right at the end of the safety area with a nasty drop at the end. How do you cancel reverse when stopped without the residual forward thrust inherent with cancellation from full reverse, trickling the aircraft over the cliff?
OK - I confess it is a bit far fetched but sometimes a bit of lateral thinking doesn't do you any harm; especially if there is nothing in the book about such a non-normal. And neither does there need to be.
Answer? At the moment the aircraft stops right at the end (your lucky day) cut both start levers while the engines are still at full reverse. With a bit of luck, there will be little or no forward thrust to roll you over the cliff with no brakes.
Writer quickly exits stage left..
It wasn't until the English second language pilots were advised to carefully read (and understand) the FCTM instructions about the need to allow the N1 to reach idle reverse before cancelling, that the penny dropped they were doing it all wrong.
It got me thinking about landing with loss of all hydraulic braking capability - rare though that possibility could be, of course. The scenario in the simulator was concerned with the use of reverse thrust and the aircraft managing to stop still in full reverse right at the end of the safety area with a nasty drop at the end. How do you cancel reverse when stopped without the residual forward thrust inherent with cancellation from full reverse, trickling the aircraft over the cliff?
OK - I confess it is a bit far fetched but sometimes a bit of lateral thinking doesn't do you any harm; especially if there is nothing in the book about such a non-normal. And neither does there need to be.
Answer? At the moment the aircraft stops right at the end (your lucky day) cut both start levers while the engines are still at full reverse. With a bit of luck, there will be little or no forward thrust to roll you over the cliff with no brakes.
Writer quickly exits stage left..
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Or just go to idle reverse and let the plane back up a before cancelling
While training crews in Asia who were used to their company procedures (not necessarily Boeing FCTM procedures), it was noticed they tended to completely cancel reverse thrust at the 60 knots call during the landing run. At the call of 60 knots, they would slam the reverse thrust levers fully down from full reverse (Boeing 737). This would cause the aircraft to momentarily accelerate down the runway while the pilot was still also applying the brakes. The reason being the N1 would be still running down through around 60% N1 when the reverser lights went out; thus giving momentarily significant forward thrust.
It wasn't until the English second language pilots were advised to carefully read (and understand) the FCTM instructions about the need to allow the N1 to reach idle reverse before cancelling, that the penny dropped they were doing it all wrong.
It got me thinking about landing with loss of all hydraulic braking capability - rare though that possibility could be, of course. The scenario in the simulator was concerned with the use of reverse thrust and the aircraft managing to stop still in full reverse right at the end of the safety area with a nasty drop at the end. How do you cancel reverse when stopped without the residual forward thrust inherent with cancellation from full reverse, trickling the aircraft over the cliff?
OK - I confess it is a bit far fetched but sometimes a bit of lateral thinking doesn't do you any harm; especially if there is nothing in the book about such a non-normal. And neither does there need to be.
Answer? At the moment the aircraft stops right at the end (your lucky day) cut both start levers while the engines are still at full reverse. With a bit of luck, there will be little or no forward thrust to roll you over the cliff with no brakes.
Writer quickly exits stage left..
It wasn't until the English second language pilots were advised to carefully read (and understand) the FCTM instructions about the need to allow the N1 to reach idle reverse before cancelling, that the penny dropped they were doing it all wrong.
It got me thinking about landing with loss of all hydraulic braking capability - rare though that possibility could be, of course. The scenario in the simulator was concerned with the use of reverse thrust and the aircraft managing to stop still in full reverse right at the end of the safety area with a nasty drop at the end. How do you cancel reverse when stopped without the residual forward thrust inherent with cancellation from full reverse, trickling the aircraft over the cliff?
OK - I confess it is a bit far fetched but sometimes a bit of lateral thinking doesn't do you any harm; especially if there is nothing in the book about such a non-normal. And neither does there need to be.
Answer? At the moment the aircraft stops right at the end (your lucky day) cut both start levers while the engines are still at full reverse. With a bit of luck, there will be little or no forward thrust to roll you over the cliff with no brakes.
Writer quickly exits stage left..
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Quite a while back, some airliners with tail mounted engines (DC-9/MD-80, 727’s, certain Fokkers) routinely used reverse to “power back” off a gate to save cost of having extra tugs. I think someone eventually figured out that the cost of fuel and wear on the engines was more than the cost of the tug.
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If you do not stow the reversers upon reaching the taxiway you risk ingesting FOD and other stuff, as an A319 crew found out when they exited the runway in wintery conditions with the reversers still deployed. The low swung engines ingested de-icing chemicals, which caused smoke en fumes in the cabin, which led to an emergency evacuation initiated by the cabin crew (!).
Report: Easyjet A319 at Belfast on Jan 6th 2011, taxiway de-icing prompts evacuation
Anyway, Airbus FCTM says: stow reversers before leaving the runway to avoid ingesting FOD. Seems pretty sensible to me.
Report: Easyjet A319 at Belfast on Jan 6th 2011, taxiway de-icing prompts evacuation
Anyway, Airbus FCTM says: stow reversers before leaving the runway to avoid ingesting FOD. Seems pretty sensible to me.
We're to be fully out of reverse by 60 kts.
You can't get it more clearer than that.
Someone needs to tell the man writing the Airbus manuals, that most airports won’t accept you being at taxi speed before leaving the runway. It defeats the whole purpose of high speed exits. And icy conditions aside, I believe the HS exits were well swept by the previous aircraft vacating!