cameronmd80
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DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Sun Aug 18, 2019 3:16 pm

https://youtu.be/NCSpFOe0Yl4
Video of the landing and aftermath.

Approx 2:30PM, Aug 17th 2019
DL651 Travelling from The Turks and Caicos to Atlanta suffered an engine failure while passing over the Bahamas. They diverted to Nassau. Fortunately, the landing was uneventful. The passengers disembarked about an hour later and their replacement flight arrived to pick them up a little before 9PM.
Now I guess the wait is on for Delta to send an engine replacement.
 
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lightsaber
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Sun Aug 18, 2019 3:27 pm

CFM-56-5B on an A320.

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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Sun Aug 18, 2019 6:48 pm

lightsaber wrote:
CFM-56-5B on an A320.

Lightsaber


DL's A320s and A319s have the -5A engines, actually
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Sun Aug 18, 2019 11:57 pm

ADM94 wrote:
lightsaber wrote:
CFM-56-5B on an A320.

Lightsaber


DL's A320s and A319s have the -5A engines, actually

Per the FAA, N335NW is a A320-212, so equipped with a CFM56-5A3.
 
crownvic
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 3:27 am

As I am not a pilot, I saw something on landing, that I do not understand. As soon as they touched down, they deployed the thrust reverser on what is likely the operational engine (only). Would this not cause an asymmetric event on the aircraft where control can be lost???
 
bradyj23
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 3:34 am

crownvic wrote:
As I am not a pilot, I saw something on landing, that I do not understand. As soon as they touched down, they deployed the thrust reverser on what is likely the operational engine (only). Would this not cause an asymmetric event on the aircraft where control can be lost???


Just because you deploy the thrust reverser doesn't mean you go into full reverse. With that being said, the asymmetric thrust can be overcome by the rudder and nose wheel (once on the ground). Hope that helps.
 
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 3:45 am

bradyj23 wrote:
crownvic wrote:
As I am not a pilot, I saw something on landing, that I do not understand. As soon as they touched down, they deployed the thrust reverser on what is likely the operational engine (only). Would this not cause an asymmetric event on the aircraft where control can be lost???


Just because you deploy the thrust reverser doesn't mean you go into full reverse. With that being said, the asymmetric thrust can be overcome by the rudder and nose wheel (once on the ground). Hope that helps.


Thx for responding. OK, but why even deploy the single thrust reverser in a situation where you already have other issues going on? Just seems to me that so many landings I have had in recent time regardless of runway length, many airlines do not even bother with reverse thrust anymore. Is it because the single engine landing requires a higher landing speed?
 
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 3:50 am

crownvic wrote:
bradyj23 wrote:
crownvic wrote:
As I am not a pilot, I saw something on landing, that I do not understand. As soon as they touched down, they deployed the thrust reverser on what is likely the operational engine (only). Would this not cause an asymmetric event on the aircraft where control can be lost???


Just because you deploy the thrust reverser doesn't mean you go into full reverse. With that being said, the asymmetric thrust can be overcome by the rudder and nose wheel (once on the ground). Hope that helps.


Thx for responding. OK, but why even deploy the single thrust reverser in a situation where you already have other issues going on? Just seems to me that so many landings I have had in recent time regardless of runway length, many airlines do not even bother with reverse thrust anymore. Is it because the single engine landing requires a higher landing speed?


You always open the thrust reverses in case you need them. Using reverse thrust on one engine is very easy to overcome the assymetry
 
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 3:57 am

crownvic wrote:
bradyj23 wrote:
crownvic wrote:
As I am not a pilot, I saw something on landing, that I do not understand. As soon as they touched down, they deployed the thrust reverser on what is likely the operational engine (only). Would this not cause an asymmetric event on the aircraft where control can be lost???


Just because you deploy the thrust reverser doesn't mean you go into full reverse. With that being said, the asymmetric thrust can be overcome by the rudder and nose wheel (once on the ground). Hope that helps.


Thx for responding. OK, but why even deploy the single thrust reverser in a situation where you already have other issues going on? Just seems to me that so many landings I have had in recent time regardless of runway length, many airlines do not even bother with reverse thrust anymore. Is it because the single engine landing requires a higher landing speed?


Don't know who you have been flying with that doesn't use thrust reverse at all. I would say that is the exception rather than the norm. I would ask, why would you not use it? Higher approach speed means much more braking is needed. Thrust reverse decreases landing distance, decreases required braking, keeps with SOP of what you do on every flight, which all increases your margin for error. There really is no reason not to use it in this situation.
 
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 3:57 am

CriticalPoint wrote:
crownvic wrote:
bradyj23 wrote:

Just because you deploy the thrust reverser doesn't mean you go into full reverse. With that being said, the asymmetric thrust can be overcome by the rudder and nose wheel (once on the ground). Hope that helps.


Thx for responding. OK, but why even deploy the single thrust reverser in a situation where you already have other issues going on? Just seems to me that so many landings I have had in recent time regardless of runway length, many airlines do not even bother with reverse thrust anymore. Is it because the single engine landing requires a higher landing speed?


You always open the thrust reverses in case you need them. Using reverse thrust on one engine is very easy to overcome the assymetry


I knew this was common on rear mounted engines (i.e. MD80), but as I am not an A320 pilot, it just seems wing mounted engines could cause instability, so I have learned something :) ...So what about a turbo prop that can go into reverse pitch? My experience with turbo props (i.e. CV-580, Dash 8) is they are far more effective in stopping a plane than jet engine thrust reversers. I have read that the thrust reverse on a jet airliner only contributes to minimal extra stopping power vs. a turboprop. Is that correct?
 
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 4:02 am

bradyj23 wrote:
crownvic wrote:
bradyj23 wrote:

Just because you deploy the thrust reverser doesn't mean you go into full reverse. With that being said, the asymmetric thrust can be overcome by the rudder and nose wheel (once on the ground). Hope that helps.


Thx for responding. OK, but why even deploy the single thrust reverser in a situation where you already have other issues going on? Just seems to me that so many landings I have had in recent time regardless of runway length, many airlines do not even bother with reverse thrust anymore. Is it because the single engine landing requires a higher landing speed?


Don't know who you have been flying with that doesn't use thrust reverse at all. I would say that is the exception rather than the norm. I would ask, why would you not use it? Higher approach speed means much more braking is needed. Thrust reverse decreases landing distance, decreases required braking, keeps with SOP of what you do on every flight, which all increases your margin for error. There really is no reason not to use it in this situation.


As you are obviously a pilot, braking systems on today's aircraft are far better than they were 20+ years ago. I should probably correct myself in saying that the reversers are deployed, but the engine thrust is just not applied. My guess is, this is a fuel savings and engine wear option that airlines tell their pilots to follow, unless thrust reverse must be applied. Sorry, but as I mentioned previously, I am encountering more and more flights where only brakes are used. My last flight was a DL A350 and after a transpac crossing, no thrust reverse was applied.
 
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 4:33 am

crownvic wrote:
My last flight was a DL A350 and after a transpac crossing, no thrust reverse was applied.


I would guarantee that reverse was selected, just idle reverse. I normally use idle reverse after having done a landing distance assessment for no reverse. Still will select maximum reverse if needed.

Not that uncommon fir thrust reverse MEL items, with one side deactivated. For landing the normal procedure is still to select reverse.
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 5:52 am

zeke wrote:
crownvic wrote:
My last flight was a DL A350 and after a transpac crossing, no thrust reverse was applied.


I would guarantee that reverse was selected, just idle reverse. I normally use idle reverse after having done a landing distance assessment for no reverse. Still will select maximum reverse if needed.

Not that uncommon fir thrust reverse MEL items, with one side deactivated. For landing the normal procedure is still to select reverse.


What is idle reverse?
 
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 5:56 am

Since this was a diversion for a flight from one country to another and landing in a third, how were the passengers processed? Does Nassau airport have a secure holding facility so that passengers would not have to enter and exit the country?
 
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 8:24 am

questions wrote:
Since this was a diversion for a flight from one country to another and landing in a third, how were the passengers processed? Does Nassau airport have a secure holding facility so that passengers would not have to enter and exit the country?

IDK about how it would be handled, although I will say there is a US pre-clearance facility at NAS
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 8:48 am

questions wrote:
zeke wrote:
crownvic wrote:
My last flight was a DL A350 and after a transpac crossing, no thrust reverse was applied.


I would guarantee that reverse was selected, just idle reverse. I normally use idle reverse after having done a landing distance assessment for no reverse. Still will select maximum reverse if needed.

Not that uncommon fir thrust reverse MEL items, with one side deactivated. For landing the normal procedure is still to select reverse.


What is idle reverse?



From what i know it is putting the thrust levers into the Reverse Position, but only that and NOT actually bringing them back to any sort of "power" position. I suppose it would be SORT OF similar if you could compare it to driving a car / truck if you were to put it into Reverse but not touch the gas with some very obvious differences since doing that in a moving vehicle while moving at highway speeds would probably cost a a few $1,000 in damages,,, but as close of an example as i can think of.
 
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 8:56 am

There are some airports particularly in Europe that limit the use of reverse thrust to idle when landing during the twilight hours. Certainly if you require any amount of reverse for safety reasons its there and you can justify it later. Procedurally you should always have the thrust levers in idle reverse for landing just in case you need the deceleration should the brakes fail for instance. Asymmetric thrust normally is not much of an issue unless you lose traction on a slippery runway but that combo would make for a very bad day!
 
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 9:35 am

In the US, pilots seem to use lots of reverse thrust on landing, but in many other parts of the world, it's used sparingly, if at all.

The 737 (especially the 900) has a very high approach speed, so reverse thrust would be needed more for those aircraft (and there are lots of them in the US).
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 9:57 am

bgm wrote:
In the US, pilots seem to use lots of reverse thrust on landing, but in many other parts of the world, it's used sparingly, if at all.

The 737 (especially the 900) has a very high approach speed, so reverse thrust would be needed more for those aircraft (and there are lots of them in the US).


Living in Europe, I have never seen/been on one landing where the reverse thrust isn't used, and that includes Q400s and A320s on a 12500ft runway (aka when it's not necessary per se). Reverse thrust is the global standard procedure. It's always used unless there's a problem of sorts. Now wether that's idle reverse or not that's another story.
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 10:04 am

bgm wrote:

The 737 (especially the 900) has a very high approach speed, .

i was told -900 has less approach speed than -800 due to SFP
 
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 10:05 am

Also don't forget that working jet engines are always generating some thrust, even at idle. If you don't put them in reverse on landing then your brakes also have to work against that thrust, even though it would be a very small percentage of the total energy.
 
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 2:45 pm

I always use reverse. I start at idle then pull about 2 knobs width or more if necessary. I start reducing to idle as I slow below 80kts to idle reverse. I keep them in idle reverse until taxi speed...less than 20kts (just how it recommends in the manual). I see some poor techniques like coming completely out of reverse at 80 and then trying to make a high speed turnoff on a wet day....yup, there are some that are not very smart....

Single reverser( due to whatever like a maintenance issue) I’ll just use idle reverse unless more is necessary until taxi speed. It’s not hard.....
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 2:57 pm

FWIW, I've done max reverse on an A320 with the other reverse INOP and pinned and there is no directional control issues. It handles just fine.
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 6:41 pm

crownvic wrote:
Dash 8


OA940 wrote:
Q400s


It is more than likely that what you experienced was not reverse at all, but what Bombardier calls "discing": the blades are set to a position where they produce no forward thrust at all and give maximum drag, so the props act like giant 4 meter airbrakes. Discing is also the root cause of the Q400's characteristic deep growl on the ground. You could even call it the Dash 8's version of ground idle.

Reverse on the Q400 is often next to useless; a lot of noise, but little actual effect compared to discing + wheel brakes (certainly not enough to warrant regular use on runways longer than 1500 m).
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 7:20 pm

Armadillo1 wrote:
bgm wrote:

The 737 (especially the 900) has a very high approach speed, .

i was told -900 has less approach speed than -800 due to SFP


That is correct, the 900ER has a slower (not much) approach speed and a slightly shorter landing distance (due to spoilers that deploy at 60 degrees) than the 800. However, it has a higher angle on landing because of this, which can result in a higher sink rate during the touchdown phase.
 
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 7:54 pm

TripleDelta wrote:
It is more than likely that what you experienced was not reverse at all, but what Bombardier calls "discing": the blades are set to a position where they produce no forward thrust at all and give maximum drag, so the props act like giant 4 meter airbrakes. Discing is also the root cause of the Q400's characteristic deep growl on the ground. You could even call it the Dash 8's version of ground idle.

Reverse on the Q400 is often next to useless; a lot of noise, but little actual effect compared to discing + wheel brakes (certainly not enough to warrant regular use on runways longer than 1500 m).


Yep. On one recent Q400 flight into PDX the pilot announced before landing that he had been asked to do an ops check on the reverse thrust, which they don't normally use on a long runway. The difference was pretty dramatic - I can't speak to the braking effect but there was certainly a lot of noise.

Maybe the takeway from all this is that the procedures for reverse thrust are far from universal.
 
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 10:43 pm

questions wrote:
What is idle reverse?


Reverser deployed with the engine at idle. Think of it like putting your car in reverse but not touching the gas. If you take your foot off the brake, you'll still go slowly in reverse, so you still have a little bit of reverse "thrust". But not much.

Standard landing config at the airline I'm training for is full flaps, LO autobrakes, and idle reverse thrust. It goes up from there depending on the situation. (Short runway you use MED autobrakes and MAX reverse thrust, for example.) So in a normal situation, you'd always use thrust reversers, but at idle thrust.
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 10:59 pm

Per our training her at delta yes it's full reverse on both engines, obviously the inop engine produces 0 thrust.
 
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Mon Aug 19, 2019 11:45 pm

TripleDelta wrote:
crownvic wrote:
Dash 8


OA940 wrote:
Q400s


It is more than likely that what you experienced was not reverse at all, but what Bombardier calls "discing": the blades are set to a position where they produce no forward thrust at all and give maximum drag, so the props act like giant 4 meter airbrakes. Discing is also the root cause of the Q400's characteristic deep growl on the ground. You could even call it the Dash 8's version of ground idle.

Reverse on the Q400 is often next to useless; a lot of noise, but little actual effect compared to discing + wheel brakes (certainly not enough to warrant regular use on runways longer than 1500 m).


Interesting. I had never heard of that. Well I can't personally attest to that but if it changes how the engine sounds significantly and if it makes you slam into the seat in front then that's definitely what I've had to go through the 10 or so times I've flown on the Dash
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Tue Aug 20, 2019 2:38 am

I find the discussion on "idle reverse" facinating. For myself, these are just negative net thrust values:
During approach, different speeds and air densities. Different thrust settings on landing (again at different thrust settings) with estimated fuel and maintenance costs. Always we must design for an engine failure scenario or a pinned thrust reverser that that condition wasn't known or overlooked by the pilot.

We use these to sell engines and address customer concerns to give options to the custom flight manuals. For airlines that must ship engines for overhaul and rent spares, they avoid thrust reverse.

For airlines like Delta, with excellent maintenance cost control and more backup engines than many, they go for the lowest cost at that day's oil price. There habit of buying end of line aircraft and aircraft having issues selling allows them to negotiate steep discounts on spare engines or they buy after seeing opportunities to buy discounted used engines.

FWIW, in my opinion, no one buys more spare engines for less than ANA, but I only post as as good as DL is, they are not the best in everything. Every airline picks their opperations manual based on their cost expectations. There are minimum guidelines, the rest is part of ancillary sales.

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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Tue Aug 20, 2019 3:07 am

Babyshark wrote:
Per our training her at delta yes it's full reverse on both engines, obviously the inop engine produces 0 thrust.


You’re trained to pull the thrust reverse tabs on both engines in the event of a single engine/engine out landing? Really?
 
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Tue Aug 20, 2019 3:09 am

To be clear though, on a dry runway, the landing distance with autobrakes is generally the same with or without reverse as the autobrakes modulate to give a fixed decel.
 
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Tue Aug 20, 2019 3:43 am

crownvic wrote:
bradyj23 wrote:
crownvic wrote:
As I am not a pilot, I saw something on landing, that I do not understand. As soon as they touched down, they deployed the thrust reverser on what is likely the operational engine (only). Would this not cause an asymmetric event on the aircraft where control can be lost???


Just because you deploy the thrust reverser doesn't mean you go into full reverse. With that being said, the asymmetric thrust can be overcome by the rudder and nose wheel (once on the ground). Hope that helps.


Thx for responding. OK, but why even deploy the single thrust reverser in a situation where you already have other issues going on? Just seems to me that so many landings I have had in recent time regardless of runway length, many airlines do not even bother with reverse thrust anymore. Is it because the single engine landing requires a higher landing speed?


Because if the runway is shorter, say on an island. You might need the added stopping power.
 
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Tue Aug 20, 2019 6:35 am

OA940 wrote:
Interesting. I had never heard of that. Well I can't personally attest to that but if it changes how the engine sounds significantly and if it makes you slam into the seat in front then that's definitely what I've had to go through the 10 or so times I've flown on the Dash


It's not the engines that are making the noise - it's the propellers. Their rapid transition from flight mode to disc creates a lot of turbulence (the pitch of the blades changes by almost 20 degrees in under two seconds + the prop RPM drops by more than a third at the same time), which causes quite a racket. During discing, the engines themselves are running at idle - so the actual braking effect comes from a combination of propeller drag* and wheel brakes (the latter are crude and need a bit to warm up - but when they do, they become pretty powerful and effective, so that may account for the rapid deceleration you experienced). Reversing produces other distinctive sounds, such as a sudden deepening of the propeller note and an pronounced increase in engine whine.

* during discing, the props do actually produce some reverse thrust... but very, very little. When you're empty or very light, if you release the parking brake you will eventually start to move backwards very slowly; but the overall influence on landing is negligible compared to the disc and brakes combo

Despite its weight (for a turboprop) and approach speeds (which are on par with those of the A320 unless full flaps are used), in normal everyday ops the Q400 really has no need for reverse - at least not at the majority of airports it operates to in Europe (bar really short strips in Norway and Greece). If you need to, you can bring it to a full stop after a ground roll of just 800 meters using only discing and brakes... even with a full cabin.
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Tue Aug 20, 2019 7:33 am

According to the official Airbus procedures full reverse is standard on the A320. Some airlines change this to reduce maintenance costs and also some airports only allow the use of full reverse for ‚safety reasons‘ (I.e. if really required). It is allowable to use idle reverse on dry runways - if idle reverse is to be used on wet runways the landing performance calculation has to be done with the braking action assumed to be ‚medium to poor‘ (which is extremely conservative as a simply wet runway will usually give you good braking action). If the landing distance is still sufficient with this calculation idle reverse may be used.
The main benefit of reverse is not stopping distance (for a given autobrake setting the landing distance won’t change as the autobrake aims for a constant deceleration rate - therefore it will actually reduce wheel braking once the reverse is deployed to keep the rate constant). But the use of reverse will lower brake temperatures which can be useful in short turnarounds in aircraft not equipped with brake fans. The maximum brake temperature before takeoff is 300C - if this is not reached in time the takeoff will have to be delayed...
(All of this applies to the A320 series and the official Airbus procedures - it will be different for other types)
 
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Re: DELTA Engine Failure , Emergency Landing in the Bahamas (N335NW / DL651)

Tue Aug 20, 2019 4:53 pm

TripleDelta wrote:
OA940 wrote:
Interesting. I had never heard of that. Well I can't personally attest to that but if it changes how the engine sounds significantly and if it makes you slam into the seat in front then that's definitely what I've had to go through the 10 or so times I've flown on the Dash


It's not the engines that are making the noise - it's the propellers. Their rapid transition from flight mode to disc creates a lot of turbulence (the pitch of the blades changes by almost 20 degrees in under two seconds + the prop RPM drops by more than a third at the same time), which causes quite a racket. During discing, the engines themselves are running at idle - so the actual braking effect comes from a combination of propeller drag* and wheel brakes (the latter are crude and need a bit to warm up - but when they do, they become pretty powerful and effective, so that may account for the rapid deceleration you experienced). Reversing produces other distinctive sounds, such as a sudden deepening of the propeller note and an pronounced increase in engine whine.

* during discing, the props do actually produce some reverse thrust... but very, very little. When you're empty or very light, if you release the parking brake you will eventually start to move backwards very slowly; but the overall influence on landing is negligible compared to the disc and brakes combo

Despite its weight (for a turboprop) and approach speeds (which are on par with those of the A320 unless full flaps are used), in normal everyday ops the Q400 really has no need for reverse - at least not at the majority of airports it operates to in Europe (bar really short strips in Norway and Greece). If you need to, you can bring it to a full stop after a ground roll of just 800 meters using only discing and brakes... even with a full cabin.


Very interesting. Thanks for the info. Also as a sidenote, at least as far as I know both OA and Wideroe use smaller planes than the Q400 on the short-runway airports (under 4000ft or so). I think that's why OA brought onboard the ATR 42s. They can fly at the same airports the Q100 can and they get extra seats out of them. However idk if there are airlines that send Q400s to very short runways like those in Norway or Greece. (Upon further research the current shortest runway OA sends its Q400s to now is 4500ft or so)
A350/CSeries = bae

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