Author Topic: With Travel Halted, What Happens To The Planes?  (Read 6858 times)

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Offline Brumby

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Re: With Travel Halted, What Happens To The Planes?
« Reply #25 on: August 11, 2020, 04:01:56 am »
I am not surprised that both pilots mentioned had glider ratings. With that experience, one learns from your first flight that without power, you get one and only one chance for a successful landing.

You don't need to be any sort of pilot to understand that.
 

Offline jogri

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Re: With Travel Halted, What Happens To The Planes?
« Reply #26 on: August 11, 2020, 11:30:34 am »
120km glide over the open ocean to the Azores (and they still had to lose excess altitude!).  A good example of how airliners are more like massive self launching sailplanes than we give them credit for.

Modern jets like the A320 or the 737 have glide ratios of 15-20 (sailplanes are in the range of 50-70:1), that means they can travel 15-20 miles for every mile they drop in altitude. If you start at normal flight levels of 10-12km you can glide up to 200km (or even more if you can use thermal updrafts). The main problem is that you have to get creative when it comes to slowing down as you probably can't use reverse thrust (and maybe even flaps if you are especially unlucky), if you don't have a rather long runway you might overshoot.

Btw, if we exclude intentional stalls (that won't be gliding) you can't realistically achieve a worse glide ratio than 4-5:1. NASA used heavily modified Gulfstream jets as a training vehicle for Space Shuttle pilots, and they had to extend the gears and flaps and use full reverse thrust to get a plane that was as bad at gliding as the Shuttle (it just doesn't have big enough wings to be a decent glider).
 

Online langwadt

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Re: With Travel Halted, What Happens To The Planes?
« Reply #27 on: August 11, 2020, 12:49:12 pm »
120km glide over the open ocean to the Azores (and they still had to lose excess altitude!).  A good example of how airliners are more like massive self launching sailplanes than we give them credit for.

Modern jets like the A320 or the 737 have glide ratios of 15-20 (sailplanes are in the range of 50-70:1), that means they can travel 15-20 miles for every mile they drop in altitude. If you start at normal flight levels of 10-12km you can glide up to 200km (or even more if you can use thermal updrafts). The main problem is that you have to get creative when it comes to slowing down as you probably can't use reverse thrust (and maybe even flaps if you are especially unlucky), if you don't have a rather long runway you might overshoot.

Btw, if we exclude intentional stalls (that won't be gliding) you can't realistically achieve a worse glide ratio than 4-5:1. NASA used heavily modified Gulfstream jets as a training vehicle for Space Shuttle pilots, and they had to extend the gears and flaps and use full reverse thrust to get a plane that was as bad at gliding as the Shuttle (it just doesn't have big enough wings to be a decent glider).

afaik thrust reversers are never a requirement for safe landing, it just saves on brakes and might help a bit if it is very wet
the A380 doesn't even thrust reversers on all it's engines

I think I've read some where that the glide ratio on a wingsuit is ~2 .5:1

 

Offline ConKbot

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Re: With Travel Halted, What Happens To The Planes?
« Reply #28 on: August 12, 2020, 01:21:25 am »

I think I've read some where that the glide ratio on a wingsuit is ~2 .5:1

Wouldn't be that surprising. Mike Patey filmed a stunt where a wingsuit flyer held the wingtip of his plane, requiring heaps of reverse thrust (negative angle on the variable pitch prop), so he could be in a step enough dive and not speed away from the skydiver.

https://youtu.be/Jdccr7qm5NA

So at least a couple hundred HP in reverse to begin to match their glide ratio.
 

Offline jogri

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Re: With Travel Halted, What Happens To The Planes?
« Reply #29 on: August 12, 2020, 07:01:24 am »
afaik thrust reversers are never a requirement for safe landing, it just saves on brakes and might help a bit if it is very wet
the A380 doesn't even thrust reversers on all it's engines

I think I've read some where that the glide ratio on a wingsuit is ~2 .5:1

Yes, technically thrust reverser are optional on a dry runway and you can land without them, but you shouldn't do it... This is what it looks like when you try to stop a 747 with worn out brakes without thrust reversers:



The A380 doesn't have thrust reversers on its outer engines because those aren't over the asphalt of a normal airstrip and you would blow up a lot of debris from the ground/grass that then gets sucked into the engines.
 

Online langwadt

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Re: With Travel Halted, What Happens To The Planes?
« Reply #30 on: August 12, 2020, 08:43:56 am »
afaik thrust reversers are never a requirement for safe landing, it just saves on brakes and might help a bit if it is very wet
the A380 doesn't even thrust reversers on all it's engines

I think I've read some where that the glide ratio on a wingsuit is ~2 .5:1

Yes, technically thrust reverser are optional on a dry runway and you can land without them, but you shouldn't do it... This is what it looks like when you try to stop a 747 with worn out brakes without thrust reversers:



that's not a landing that is an aborted takeoff

 

Offline jogri

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Re: With Travel Halted, What Happens To The Planes?
« Reply #31 on: August 12, 2020, 04:45:10 pm »
that's not a landing that is an aborted takeoff

Yeah, and a nominal V1 (maximum speed at which a start can be aborted) is around 160 knots while a landing with MTOW will get you in the same range (usual landing speeds are in the 130-150 knots range)... So the only main difference is that the tires never left the ground for the aborted takeoff, but other than that a fast landing produces a similar strain on the aircraft than an aborted takeoff.
 

Online langwadt

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Re: With Travel Halted, What Happens To The Planes?
« Reply #32 on: August 12, 2020, 06:35:13 pm »
that's not a landing that is an aborted takeoff

Yeah, and a nominal V1 (maximum speed at which a start can be aborted) is around 160 knots while a landing with MTOW will get you in the same range (usual landing speeds are in the 130-150 knots range)... So the only main difference is that the tires never left the ground for the aborted takeoff, but other than that a fast landing produces a similar strain on the aircraft than an aborted takeoff.

at an aborted takeoff there probably much less runway left to stop on, braking is much much harder

afaik thrust reversers are not even on the minium equipment list

 

Offline jogri

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Re: With Travel Halted, What Happens To The Planes?
« Reply #33 on: August 12, 2020, 06:54:59 pm »
Well, every airplane with a certificate of airworthiness is capable of slowing down to a stop without thrust reversers... Albeit with significant damage to the landing gear, especially the tires.

Btw, i just checked the MMEL for the A320, this is what it says about thrust reversers being inoperative:

Quote
(M)(O) One may be inoperative provided: a)   Inoperative reverser is deactivated and secured in the stowed position, and no operations or procedures require its use,
b)   All stow and deploy switches on the inoperative reverser operate normally (CFM only), 
c)   Both LVDT on the inoperative reverser are checked operative (IAE only),   
d)   ENG 1 (2) REV INHIBITED caution is displayed on ECAM E/WD after deactivation (PW only),   
e)   ENG 1 (2) REV UNLOCKED caution is not present on ECAM E/WD after deactivation (PW only)     
f)    ENG 1 (2) REV PRESSURIZED caution is not present on ECAM E/WD after deactivation,
g)   Wheel brake tachometers operate normally, 
h)   Main wheel braking system operates normally

Sounds like a "technically you can fly with only one reverser, but get it fixed ASAP". I'll take a bet and say that the airline uses this exception to get the plane to a workshop as soon as possible because every additional failure in the propulsion/breaking system is going to get the plane grounded.
 

Online langwadt

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Re: With Travel Halted, What Happens To The Planes?
« Reply #34 on: August 12, 2020, 08:20:13 pm »
Well, every airplane with a certificate of airworthiness is capable of slowing down to a stop without thrust reversers... Albeit with significant damage to the landing gear, especially the tires.

Btw, i just checked the MMEL for the A320, this is what it says about thrust reversers being inoperative:

Quote
(M)(O) One may be inoperative provided: a)   Inoperative reverser is deactivated and secured in the stowed position, and no operations or procedures require its use,
b)   All stow and deploy switches on the inoperative reverser operate normally (CFM only), 
c)   Both LVDT on the inoperative reverser are checked operative (IAE only),   
d)   ENG 1 (2) REV INHIBITED caution is displayed on ECAM E/WD after deactivation (PW only),   
e)   ENG 1 (2) REV UNLOCKED caution is not present on ECAM E/WD after deactivation (PW only)     
f)    ENG 1 (2) REV PRESSURIZED caution is not present on ECAM E/WD after deactivation,
g)   Wheel brake tachometers operate normally, 
h)   Main wheel braking system operates normally

Sounds like a "technically you can fly with only one reverser, but get it fixed ASAP". I'll take a bet and say that the airline uses this exception to get the plane to a workshop as soon as possible because every additional failure in the propulsion/breaking system is going to get the plane grounded.

sure brake pads and the time to change them cost money, but

https://youtu.be/NkrozyWKCHY

 

Offline cdev

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Re: With Travel Halted, What Happens To The Planes?
« Reply #35 on: August 12, 2020, 08:30:19 pm »
I suppose some could do what this man has done..  Live in one...



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Offline SkyMaster

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Re: With Travel Halted, What Happens To The Planes?
« Reply #36 on: August 12, 2020, 09:00:59 pm »
that's not a landing that is an aborted takeoff

Yeah, and a nominal V1 (maximum speed at which a start can be aborted) is around 160 knots while a landing with MTOW will get you in the same range (usual landing speeds are in the 130-150 knots range)... So the only main difference is that the tires never left the ground for the aborted takeoff, but other than that a fast landing produces a similar strain on the aircraft than an aborted takeoff.

I would be surprised if it is possible to land a B747 at Maximum take-off weight (MTOW).

The flight manual and SOP (airline standard operating procedure) probably limit the weight at which the B747 can land. And, after taking off at MTOW, the B747 would not be at MTOW anyway... because... fuel burn  ;)

 :)
 

Offline jogri

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Re: With Travel Halted, What Happens To The Planes?
« Reply #37 on: August 12, 2020, 09:05:55 pm »
sure brake pads and the time to change them cost money

Those are videos from runway 05R, the taxiway is at the end of a 3.2 km long runway so the pilot has to drive down the runway anyway to reach the gates... So why bother? It gives you a smoother landing, cuts down the time required to reach the gate and avoids the chance of foreign object damage. And since the plane doesn't land with its maximum take-off weight the brakes don't have to work that hard (a full 747 has fuel for 16h, and you typically have enough fuel for ~1h of flight left when you land, that alone can be a difference of up to 150 tons between take-off and landing)


I would be surprised if it is possible to land a B747 at Maximum take-off weight (MTOW).

The flight manual and SOP (airline standard operating procedure) probably limit the weight at which the B747 can land. And, after taking off at MTOW, the B747 would not be at MTOW anyway... because... fuel burn  ;)

 :)

Well, you could probably get it down in one piece but at the cost of a totaled airframe... Or you cold proceed to dump 100 tons of fuel, but that's going to take some time (probably around an hour given that you first have to find an appropriate spot).
 

Online langwadt

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Re: With Travel Halted, What Happens To The Planes?
« Reply #38 on: August 12, 2020, 09:15:37 pm »
that's not a landing that is an aborted takeoff

Yeah, and a nominal V1 (maximum speed at which a start can be aborted) is around 160 knots while a landing with MTOW will get you in the same range (usual landing speeds are in the 130-150 knots range)... So the only main difference is that the tires never left the ground for the aborted takeoff, but other than that a fast landing produces a similar strain on the aircraft than an aborted takeoff.

I would be surprised if it is possible to land a B747 at Maximum take-off weight (MTOW).

The flight manual and SOP (airline standard operating procedure) probably limit the weight at which the B747 can land. And, after taking off at MTOW, the B747 would not be at MTOW anyway... because... fuel burn  ;)

 :)

google says: Maximum take-off weight for 747 is roughly 400tons depending on model, and maximum landing weight is roughly 100tons less

 

Online langwadt

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Re: With Travel Halted, What Happens To The Planes?
« Reply #39 on: August 12, 2020, 09:21:40 pm »
sure brake pads and the time to change them cost money

Those are videos from runway 05R, the taxiway is at the end of a 3.2 km long runway so the pilot has to drive down the runway anyway to reach the gates... So why bother? It gives you a smoother landing, cuts down the time required to reach the gate and avoids the chance of foreign object damage. And since the plane doesn't land with its maximum take-off weight the brakes don't have to work that hard (a full 747 has fuel for 16h, and you typically have enough fuel for ~1h of flight left when you land, that alone can be a difference of up to 150 tons between take-off and landing)


I would be surprised if it is possible to land a B747 at Maximum take-off weight (MTOW).

The flight manual and SOP (airline standard operating procedure) probably limit the weight at which the B747 can land. And, after taking off at MTOW, the B747 would not be at MTOW anyway... because... fuel burn  ;)

 :)

Well, you could probably get it down in one piece but at the cost of a totaled airframe... Or you cold proceed to dump 100 tons of fuel, but that's going to take some time (probably around an hour given that you first have to find an appropriate spot).

google..  747 fuel capacity ~200tons, fuel consumption London to New York ~70tons,  time to dump 100tons ~55 minutes

 

Online langwadt

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Re: With Travel Halted, What Happens To The Planes?
« Reply #40 on: August 12, 2020, 09:32:59 pm »
sure brake pads and the time to change them cost money

Those are videos from runway 05R, the taxiway is at the end of a 3.2 km long runway so the pilot has to drive down the runway anyway to reach the gates... So why bother? It gives you a smoother landing, cuts down the time required to reach the gate and avoids the chance of foreign object damage. And since the plane doesn't land with its maximum take-off weight the brakes don't have to work that hard (a full 747 has fuel for 16h, and you typically have enough fuel for ~1h of flight left when you land, that alone can be a difference of up to 150 tons between take-off and landing)


I would be surprised if it is possible to land a B747 at Maximum take-off weight (MTOW).

The flight manual and SOP (airline standard operating procedure) probably limit the weight at which the B747 can land. And, after taking off at MTOW, the B747 would not be at MTOW anyway... because... fuel burn  ;)

 :)

Well, you could probably get it down in one piece but at the cost of a totaled airframe... Or you cold proceed to dump 100 tons of fuel, but that's going to take some time (probably around an hour given that you first have to find an appropriate spot).

looks like landing a 747 at MTOW is not a big issue, https://www.boeing.com/commercial/aeromagazine/articles/qtr_3_07/article_03_3.html


 

Offline SkyMaster

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Re: With Travel Halted, What Happens To The Planes?
« Reply #41 on: August 12, 2020, 10:15:17 pm »

...

looks like landing a 747 at MTOW is not a big issue, https://www.boeing.com/commercial/aeromagazine/articles/qtr_3_07/article_03_3.html

Wait a minute, in a previous post you claimed the B747 Maximum landing weight was 100 tons less than the Maximum take-off weight, and now you are saying that landing a B747 at a weight near MTOW is not a big issue;)

The article you are referring to, at the beginning read "Landing overweight requires an overweight landing inspection with its associated cost.", and then near the end, read "... The Boeing airplane maintenance manual (AMM) provides a special inspection that is required any time an overweight landing occurs, regardless of how smooth the landing.".

I think the article's intent is to claim that the Boeing 747 structure is designed to survive such an abnormal situation, without damage.

 :)
« Last Edit: August 12, 2020, 10:17:19 pm by SkyMaster »
 

Online langwadt

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Re: With Travel Halted, What Happens To The Planes?
« Reply #42 on: August 12, 2020, 10:36:42 pm »

...

looks like landing a 747 at MTOW is not a big issue, https://www.boeing.com/commercial/aeromagazine/articles/qtr_3_07/article_03_3.html

Wait a minute, in a previous post you claimed the B747 Maximum landing weight was 100 tons less than the Maximum take-off weight, and now you are saying that landing a B747 at a weight near MTOW is not a big issue;)

The article you are referring to, at the beginning read "Landing overweight requires an overweight landing inspection with its associated cost.", and then near the end, read "... The Boeing airplane maintenance manual (AMM) provides a special inspection that is required any time an overweight landing occurs, regardless of how smooth the landing.".

I think the article's intent is to claim that the Boeing 747 structure is designed to survive such an abnormal situation, without damage.

 :)

yes, so while you should preferably to stay below maximum landing weight, if you have to, even a hard landing at MTOW is
not going to make the plane fall apart it just needs an inspection.

one of allowable reasons for an overweight landing is "Serious illness of crew or passengers which would require immediate medical attention."  If there was a serious risk from an overweight landing I doubt someone needing medical attention would be a good enough reason




 

Offline SkyMaster

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Re: With Travel Halted, What Happens To The Planes?
« Reply #43 on: August 13, 2020, 01:47:33 am »


yes, so while you should preferably to stay below maximum landing weight, if you have to, even a hard landing at MTOW is
not going to make the plane fall apart it just needs an inspection.

one of allowable reasons for an overweight landing is "Serious illness of crew or passengers which would require immediate medical attention."  If there was a serious risk from an overweight landing I doubt someone needing medical attention would be a good enough reason

Well, a hard landing on a large aircraft is serious situation. The option of landing overweight is going to be specified in the airline's SOP (Standard operating procedures).

Below is what a hard landing can do:



This occurred during a test flight; the test plan was not calling for a hard landing, the crew inadvertently did a hard landing. An FAA inspector was standing up at the time of the landing and the impact was such that he broke an ankle. And for the aircraft damage, you can watch the video, it is only a few seconds long. Among other things, you will see the fuselage flex like a wet noodle; but this is not all. And this was a DC-9; a little bird.

 :)
 

Online Alex EisenhutTopic starter

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Re: With Travel Halted, What Happens To The Planes?
« Reply #44 on: August 13, 2020, 04:19:49 am »
Best use of a thrust reverser



Saab makes some intense-looking airplanes.
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Offline paulca

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Re: With Travel Halted, What Happens To The Planes?
« Reply #45 on: August 13, 2020, 10:37:16 am »
that's not a landing that is an aborted takeoff

Yeah, and a nominal V1 (maximum speed at which a start can be aborted) is around 160 knots while a landing with MTOW will get you in the same range (usual landing speeds are in the 130-150 knots range)... So the only main difference is that the tires never left the ground for the aborted takeoff, but other than that a fast landing produces a similar strain on the aircraft than an aborted takeoff.

at an aborted takeoff there probably much less runway left to stop on, braking is much much harder

afaik thrust reversers are not even on the minium equipment list

Original video looks like flight trials.  The rejected takeoff test has to be V1, maximum takeoff weight, no thrust reversers, the plane must stop on the runway and be able to exit the runway.  Meaning it must be able to put the brake fire out and taxi under it's own power off the runway.  Often when a rejected takeoff happens the brakes can go on fire and lock up, closing the runway until engineers can unlock the wheels.

No thrust reverses is because rejected takeoffs very often happen when there is an engine failure and you can't really use thrust reverses without symetric thrust. 

Thrust reversers are usually banned at airports for out of schedule movements... ie. out of hours, like at night when there are stricter noise abatement requirements.

On gliding an airliner (or anything for that matter) it's all about the number 1 gauge, speed.  Fly the pitch/aoa to maintain the speed you need and take whatever descent rate you get.  It's a recurring problem that airline pilots are so heavily trained in procedures, checklists and "flying the numbers" that they simply forget to "fly the damn plane".
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Online langwadt

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Re: With Travel Halted, What Happens To The Planes?
« Reply #46 on: August 13, 2020, 11:26:43 am »
that's not a landing that is an aborted takeoff

Yeah, and a nominal V1 (maximum speed at which a start can be aborted) is around 160 knots while a landing with MTOW will get you in the same range (usual landing speeds are in the 130-150 knots range)... So the only main difference is that the tires never left the ground for the aborted takeoff, but other than that a fast landing produces a similar strain on the aircraft than an aborted takeoff.

at an aborted takeoff there probably much less runway left to stop on, braking is much much harder

afaik thrust reversers are not even on the minium equipment list

No thrust reverses is because rejected takeoffs very often happen when there is an engine failure and you can't really use thrust reverses without symetric thrust. 

asymmetric thrust must not be a big issue since the MMEL for the A320 allows for one nonfunctional thrust reverser
 

Offline paulca

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Re: With Travel Halted, What Happens To The Planes?
« Reply #47 on: August 13, 2020, 12:02:49 pm »
that's not a landing that is an aborted takeoff

Yeah, and a nominal V1 (maximum speed at which a start can be aborted) is around 160 knots while a landing with MTOW will get you in the same range (usual landing speeds are in the 130-150 knots range)... So the only main difference is that the tires never left the ground for the aborted takeoff, but other than that a fast landing produces a similar strain on the aircraft than an aborted takeoff.

at an aborted takeoff there probably much less runway left to stop on, braking is much much harder

afaik thrust reversers are not even on the minium equipment list

No thrust reverses is because rejected takeoffs very often happen when there is an engine failure and you can't really use thrust reverses without symetric thrust. 

asymmetric thrust must not be a big issue since the MMEL for the A320 allows for one nonfunctional thrust reverser

That's odd.  "non functional" thrust reverser could also mean the actual mechanism has failed.  The throttles come up to 80% or something on reverse, if one of the engines has a broken reverser it will be producing 80% forward thrust.

I found this:
https://www.faa.gov/other_visit/aviation_industry/airline_operators/airline_safety/safo/all_safos/media/2007/SAFO07007.pdf

Which states:
Quote
Subject: Thrust Lever Position during Landing with One Deactivated Thrust Reverser on
Airbus A318, A319, A320, A321 Series Airplanes.
Purpose: This SAFO emphasizes the operational procedure of selecting idle thrust on both
engines during a landing conducted with one deactivated thrust reverser

Which is line with my thoughts that if either engine or reverser is "out of operation" then thrust reversers (or at least thrust reverser beyond idle reverse) is not permitted.

EDIT:  Although reading it more clearly the accidents were because the pilot left the non-operating reverser engine in "CLIMB" position, rather than IDLE.  It then states as to whether the pilots should move the throttles to IDLE REVERSE or MAX REVERSE is up to the airlines.  I would expect the plane itself determines in either/both/neither reverser should be activated when one is failed.

EDIT:  Remember in a normal landing the braking is automatic.  There is literally a "Auto brake selector" knob, usually, with positions "RTO, OFF, 1, 2, 3" or similar.  It sets a constant retardation rate.  1 and 2 are common settings.  The idea behind the the thrust reversers is not that the aircraft needs help to stop, but to reduce brake wear.  The aircraft MUST be able to stop with 0 reverse in all conditions, including permitted snow/ice conditions for which the aircraft is rated.
« Last Edit: August 13, 2020, 12:15:54 pm by paulca »
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Online langwadt

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Re: With Travel Halted, What Happens To The Planes?
« Reply #48 on: August 13, 2020, 12:14:25 pm »
that's not a landing that is an aborted takeoff

Yeah, and a nominal V1 (maximum speed at which a start can be aborted) is around 160 knots while a landing with MTOW will get you in the same range (usual landing speeds are in the 130-150 knots range)... So the only main difference is that the tires never left the ground for the aborted takeoff, but other than that a fast landing produces a similar strain on the aircraft than an aborted takeoff.

at an aborted takeoff there probably much less runway left to stop on, braking is much much harder

afaik thrust reversers are not even on the minium equipment list

No thrust reverses is because rejected takeoffs very often happen when there is an engine failure and you can't really use thrust reverses without symetric thrust. 

asymmetric thrust must not be a big issue since the MMEL for the A320 allows for one nonfunctional thrust reverser

That's odd.  "non functional" thrust reverser could also mean the actual mechanism has failed.  The throttles come up to 80% or something on reverse, if one of the engines has a broken reverser it will be producing 80% forward thrust.

I found this:
https://www.faa.gov/other_visit/aviation_industry/airline_operators/airline_safety/safo/all_safos/media/2007/SAFO07007.pdf

Which states:
Quote
Subject: Thrust Lever Position during Landing with One Deactivated Thrust Reverser on
Airbus A318, A319, A320, A321 Series Airplanes.
Purpose: This SAFO emphasizes the operational procedure of selecting idle thrust on both
engines during a landing conducted with one deactivated thrust reverser

Which is line with my thoughts that if either engine or reverser is "out of operation" then thrust reversers (or at least thrust reverser beyond idle reverse) is not permitted.

EDIT:  Remember in a normal landing the braking is automatic.  There is literally a "Auto brake selector" knob, usually, with positions "RTO, OFF, 1, 2, 3" or similar.  It sets a constant retardation rate.  1 and 2 are common settings.  The idea behind the the thrust reversers is not that the aircraft needs help to stop, but to reduce brake wear.  The aircraft MUST be able to stop with 0 reverse in all conditions, including permitted snow/ice conditions for which the aircraft is rated.

the way I read it the pilot should just make sure operate both throttles as normal and not only use the one with a functional reverser
 

Online NiHaoMike

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Re: With Travel Halted, What Happens To The Planes?
« Reply #49 on: August 13, 2020, 11:36:30 pm »
I suppose some could do what this man has done..  Live in one...


Looks like a great home for the technical hobbyist. Turn the cockpit into a flight simulator complete with authentic instruments and controls (easiest way probably would be to build a shed around the front part of the plane, then add projectors for video), turn the cargo bay into a RF shielded lab. The wings would make great places to mount solar panels. Perhaps the fuel tanks can be turned into thermal storage tanks by adding insulation on the outside?
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