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BWIAirport
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More Efficient Takeoff Technique

Sat Feb 03, 2018 2:33 am

Just something I've thought about recently.
Could airplanes reduce takeoff distance by beginning takeoff roll with flaps 0, thus building up speed quicker with less drag, then lowering them to takeoff setting around, say, 60 or 80 knots? Could this relax limitations at short runway or high altitude airports, such as SNA, BUR, EGE, etc?

Something maybe based off this: https://www.youtube.com/watch?v=Y7Jwde4EAVw
Notice how the plane at 0:58, albeit a Piper JC-3, begins takeoff roll with no flaps and drops them right before rotation.
Just a thought. Love to hear your input.
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Polot
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Re: More Efficient Takeoff Technique

Sat Feb 03, 2018 2:38 am

The difference in time to go 0-60/80 knots with 0 flaps versus standard flaps is likely minimal (like seconds). Drag is not really determining takeoff length at those low speeds, thrust to weight ratio is what is important then.

Then you have to consider that flaps don’t drop instanteously.
Last edited by Polot on Sat Feb 03, 2018 2:39 am, edited 1 time in total.
 
barney captain
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Re: More Efficient Takeoff Technique

Sat Feb 03, 2018 2:39 am

From a safety standpoint - a very bad idea. What if they deploy asymmetricaly - or not at all. There's a thousand reason not to do this, but no good reason to.

The takeoff warning horn wont allow you to advance the thrust levers in that state - and for a very good reason.
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cvgComair
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Re: More Efficient Takeoff Technique

Sat Feb 03, 2018 2:55 am

I see too many things wrong with this and not much benefit. There is a reason you lower the flaps before the takeoff roll. There are a lot of things that could do wrong such as flap failure, going down uneven, not going down before VR, etc. There are many other things that pilots need to pay attention to during takeoff, lowering the flaps should not be one of them.
Last edited by cvgComair on Sat Feb 03, 2018 3:12 am, edited 1 time in total.
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BoeingGuy
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Re: More Efficient Takeoff Technique

Sat Feb 03, 2018 2:57 am

barney captain wrote:
From a safety standpoint - a very bad idea. What if they deploy asymmetricaly - or not at all. There's a thousand reason not to do this, but no good reason to.

The takeoff warning horn wont allow you to advance the thrust levers in that state - and for a very good reason.


You must fly the 737 when you mention a horn. :)

All other Boeing models have an EICAS Warning “CONFIG FLAPS” if you advance to takeoff power with the flaps not in a valid takeoff setting (5-20). Also, as an added protection, the Autothrottle won’t engage for takeoff when you push TO/GA if the flaps are out of config.

All you’re doing with this proposal is asking for another Detroit or Madrid.
Last edited by BoeingGuy on Sat Feb 03, 2018 3:03 am, edited 1 time in total.
 
joffie
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Re: More Efficient Takeoff Technique

Sat Feb 03, 2018 2:59 am

I can imagine it now. 747-400 rolling down the runway with flaps 0, pilots need Flaps 20 for takeoff and by the time the flaps are at 20 plane already at the end of the runway.

Not a good idea. What if the flaps fail to deply? Too many other things to think about during the takeoff run.
 
N353SK
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Re: More Efficient Takeoff Technique

Sat Feb 03, 2018 3:07 am

If you were to delay flap setting to 60-80 knots the flaps would likely not be set in takeoff position until the airplane is traveling at 100-120 knots. If there was an issue with flap deployment this would lead to a high-speed rejected takeoff, which is extremely dangerous. A high speed rejected takeoff can lead to passenger injuries, runway overruns, brake fires, and blown tires. The potentially (tiny) fuel savings is not worth the increased risk of a rejected takeoff.
 
QF1607
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Re: More Efficient Takeoff Technique

Sat Feb 03, 2018 3:08 am

Northwest Airlines flight 255... 'nuf said
 
stratosphere
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Re: More Efficient Takeoff Technique

Sat Feb 03, 2018 3:20 am

This idea is so idiotic for any number of reasons. Any savings you think you might get by that idea is offset by the increased risk. Takeoff and landing are the most dangerous phases of flight. You do not want to do anything that interferes with any margins in those regimes. As others have said there are plenty of accidents already that attest to the risk. Of course I wouldn't put it past a bean counter to want to suggest it.
 
SammyXV
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Re: More Efficient Takeoff Technique

Sat Feb 03, 2018 3:25 am

stratosphere wrote:
This idea is so idiotic for any number of reasons. Any savings you think you might get by that idea is offset by the increased risk. Takeoff and landing are the most dangerous phases of flight. You do not want to do anything that interferes with any margins in those regimes. As others have said there are plenty of accidents already that attest to the risk. Of course I wouldn't put it past a bean counter to want to suggest it.


Well that's a negative response... Maybe this isn't the best idea but the author is thinking and possibly building towards a more viable idea.
 
BoeingGuy
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Re: More Efficient Takeoff Technique

Sat Feb 03, 2018 3:48 am

SammyXV wrote:
stratosphere wrote:
This idea is so idiotic for any number of reasons. Any savings you think you might get by that idea is offset by the increased risk. Takeoff and landing are the most dangerous phases of flight. You do not want to do anything that interferes with any margins in those regimes. As others have said there are plenty of accidents already that attest to the risk. Of course I wouldn't put it past a bean counter to want to suggest it.


Well that's a negative response... Maybe this isn't the best idea but the author is thinking and possibly building towards a more viable idea.


Although he may have worded his reply a little harshly, I’ll be blunt too. While the OP, may have been naively well intended, this is a very bad idea.
 
Max Q
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Re: More Efficient Takeoff Technique

Sat Feb 03, 2018 4:17 am

BoeingGuy wrote:
barney captain wrote:
From a safety standpoint - a very bad idea. What if they deploy asymmetricaly - or not at all. There's a thousand reason not to do this, but no good reason to.

The takeoff warning horn wont allow you to advance the thrust levers in that state - and for a very good reason.


You must fly the 737 when you mention a horn. :)

All other Boeing models have an EICAS Warning “CONFIG FLAPS” if you advance to takeoff power with the flaps not in a valid takeoff setting (5-20). Also, as an added protection, the Autothrottle won’t engage for takeoff when you push TO/GA if the flaps are out of config.

All you’re doing with this proposal is asking for another Detroit or Madrid.



Agree with most of that except the take off flap range

The B727 had a 25 degree flap take off setting, used out of short fields


In particular La Guardia which was the only
airport I remember using it.

Rotation speed was quite low and you would practically levitate off the runway.
Flaps were retracted from 25 to 15 at 400
feet accompanied by a very big pitch change that you had to be ready for, easily
compensated with elevator trim



This was how Boeing was able to meet Eastern Airlines requirement for an aircraft that could operate non stop with a full load from La Guardia’s runways (even shorter then) to Miami with a full load year round and part of the reason for the elaborate triple slotted flaps on this superb aircraft


Also, both the 757 and 767 are certified for
take offs with flaps 1 which is basically slats only
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BoeingGuy
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Re: More Efficient Takeoff Technique

Sat Feb 03, 2018 4:31 am

Max Q wrote:
BoeingGuy wrote:
barney captain wrote:
From a safety standpoint - a very bad idea. What if they deploy asymmetricaly - or not at all. There's a thousand reason not to do this, but no good reason to.

The takeoff warning horn wont allow you to advance the thrust levers in that state - and for a very good reason.


You must fly the 737 when you mention a horn. :)

All other Boeing models have an EICAS Warning “CONFIG FLAPS” if you advance to takeoff power with the flaps not in a valid takeoff setting (5-20). Also, as an added protection, the Autothrottle won’t engage for takeoff when you push TO/GA if the flaps are out of config.

All you’re doing with this proposal is asking for another Detroit or Madrid.



Agree with most of that except the take off flap range

The B727 had a 25 degree flap take off setting, used out of short fields


In particular La Guardia which was the only
airport I remember using it.

Rotation speed was quite low and you would practically levitate off the runway.
Flaps were retracted from 25 to 15 at 400
feet accompanied by a very big pitch change that you had to be ready for, easily
compensated with elevator trim



This was how Boeing was able to meet Eastern Airlines requirement for an aircraft that could operate non stop with a full load from La Guardia’s runways (even shorter then) to Miami with a full load year round and part of the reason for the elaborate triple slotted flaps on this superb aircraft


Also, both the 757 and 767 are certified for
take offs with flaps 1 which is basically slats only


Not totally correct. Only the 767-200 is certified for a Flaps 1 takeoff. The 767-300, 767-400, and KC-46 are not certified for Flaps 1 takeoff. Not sure about the 757 but I don’t believe that it’s certified for a Flaps 1 takeoff either. Put another way, except for the 737, which I’m not as familiar with, all production Boeing airplanes have takeoff flap settings 5-20 as I stated.
 
Max Q
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Re: More Efficient Takeoff Technique

Sat Feb 03, 2018 4:42 am

Correct, F1 is not approved for take off on the 764, never flew the -300 but the -200 is approved for this, slats only


The 757-200 is approved for flaps 1 take off but not the -300
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BoeingGuy
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Re: More Efficient Takeoff Technique

Sat Feb 03, 2018 4:59 am

Max Q wrote:
Correct, F1 is not approved for take off on the 764, never flew the -300 but the -200 is approved for this, slats only


The 757-200 is approved for flaps 1 take off but not the -300


It doesn’t take a genius to figure out who you flew for then. -200, -400, no -300 and 757-200 and -300.

The 767-300 isn’t approved for Flaps 1. The KC-46 is not either, even though it has a -200 fuselage. I wasn’t aware that the 757-200 is though.
 
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BWIAirport
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Re: More Efficient Takeoff Technique

Sat Feb 03, 2018 5:51 am

Definitely considered what you all are saying. I knew there must've been a good reason it wasn't happening :lol:
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BWIAirport
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Re: More Efficient Takeoff Technique

Sat Feb 03, 2018 2:09 pm

stratosphere wrote:
This idea is so idiotic for any number of reasons. Any savings you think you might get by that idea is offset by the increased risk. Takeoff and landing are the most dangerous phases of flight. You do not want to do anything that interferes with any margins in those regimes. As others have said there are plenty of accidents already that attest to the risk. Of course I wouldn't put it past a bean counter to want to suggest it.

lol dude.. I'm 20, attend a liberal arts college, and my aviation knowledge is limited to what I can find in my free time. Asking questions like this is how I learn. Sorry to waste your time.
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aemoreira1981
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Re: More Efficient Takeoff Technique

Sat Feb 03, 2018 4:18 pm

The Airbus A300 and Airbus A310 are certified for a slats only takeoff, usually used in a hot and high environment (15/0 would be Flaps 1). From a 2003 thread: viewtopic.php?t=734329 However, I don't know if any other Airbus planes can do a slats only takeoff.
 
arcticcruiser
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Re: More Efficient Takeoff Technique

Sat Feb 03, 2018 9:24 pm

BoeingGuy wrote:
Max Q wrote:
BoeingGuy wrote:

You must fly the 737 when you mention a horn. :)

All other Boeing models have an EICAS Warning “CONFIG FLAPS” if you advance to takeoff power with the flaps not in a valid takeoff setting (5-20). Also, as an added protection, the Autothrottle won’t engage for takeoff when you push TO/GA if the flaps are out of config.

All you’re doing with this proposal is asking for another Detroit or Madrid.



Agree with most of that except the take off flap range

The B727 had a 25 degree flap take off setting, used out of short fields


In particular La Guardia which was the only
airport I remember using it.

Rotation speed was quite low and you would practically levitate off the runway.
Flaps were retracted from 25 to 15 at 400
feet accompanied by a very big pitch change that you had to be ready for, easily
compensated with elevator trim



This was how Boeing was able to meet Eastern Airlines requirement for an aircraft that could operate non stop with a full load from La Guardia’s runways (even shorter then) to Miami with a full load year round and part of the reason for the elaborate triple slotted flaps on this superb aircraft


Also, both the 757 and 767 are certified for
take offs with flaps 1 which is basically slats only


Not totally correct. Only the 767-200 is certified for a Flaps 1 takeoff. The 767-300, 767-400, and KC-46 are not certified for Flaps 1 takeoff. Not sure about the 757 but I don’t believe that it’s certified for a Flaps 1 takeoff either. Put another way, except for the 737, which I’m not as familiar with, all production Boeing airplanes have takeoff flap settings 5-20 as I stated.


At least some 737NGs and the 737MAX are certified for Flap 25 take-off. Really only practical on a short runway with no obstructions. Initial climb must suffer and obstacle clearance therefore.
 
Max Q
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Re: More Efficient Takeoff Technique

Sun Feb 04, 2018 4:08 am

arcticcruiser wrote:
BoeingGuy wrote:
Max Q wrote:


Agree with most of that except the take off flap range

The B727 had a 25 degree flap take off setting, used out of short fields


In particular La Guardia which was the only
airport I remember using it.

Rotation speed was quite low and you would practically levitate off the runway.
Flaps were retracted from 25 to 15 at 400
feet accompanied by a very big pitch change that you had to be ready for, easily
compensated with elevator trim



This was how Boeing was able to meet Eastern Airlines requirement for an aircraft that could operate non stop with a full load from La Guardia’s runways (even shorter then) to Miami with a full load year round and part of the reason for the elaborate triple slotted flaps on this superb aircraft


Also, both the 757 and 767 are certified for
take offs with flaps 1 which is basically slats only


Not totally correct. Only the 767-200 is certified for a Flaps 1 takeoff. The 767-300, 767-400, and KC-46 are not certified for Flaps 1 takeoff. Not sure about the 757 but I don’t believe that it’s certified for a Flaps 1 takeoff either. Put another way, except for the 737, which I’m not as familiar with, all production Boeing airplanes have takeoff flap settings 5-20 as I stated.


At least some 737NGs and the 737MAX are certified for Flap 25 take-off. Really only practical on a short runway with no obstructions. Initial climb must suffer and obstacle clearance therefore.




Correct, that’s why we retracted flaps from
25 to 15 at 400’


That comes up really quick, it was ‘positive rate, gear up’ then almost immediately call for ‘F15’ at 400’


As you say it gets you off the ground in the shortest possible distance but climb rate suffers significantly with the drag of such a high flap setting, so almost immediately after selecting gear up at 400 the flaps would be reduced from 25 to 15


The 727 really wanted to sink with this configuration change and it required a timely application of a significant amount of nose up trim to keep it going uphill at that point and then the climb rate picked up with the huge reduction in drag


It was challenging to practice in the sim, losing an engine while the flaps were still
at 25 required an immediate reduction to 15 while also correcting for the yaw and then the pitch change, fun times


Do they have a similar procedure on the
737 ?
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GalaxyFlyer
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Re: More Efficient Takeoff Technique

Sun Feb 04, 2018 4:26 am

When would a 757-200 ever need a Flaps 1 take-off? With its thrust, I’m surprised it was needed.

GF
 
Max Q
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Re: More Efficient Takeoff Technique

Sun Feb 04, 2018 6:29 am

GalaxyFlyer wrote:
When would a 757-200 ever need a Flaps 1 take-off? With its thrust, I’m surprised it was needed.

GF



Departing a high elevation airport (9400feet) like Quito Colombia at heavy weight
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BoeingGuy
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Re: More Efficient Takeoff Technique

Sun Feb 04, 2018 8:00 pm

Max Q wrote:
GalaxyFlyer wrote:
When would a 757-200 ever need a Flaps 1 take-off? With its thrust, I’m surprised it was needed.

GF



Departing a high elevation airport (9400feet) like Quito Colombia at heavy weight


That would be the old UIO. The new airport is closer to 7000 feet, but I get your point. I thought AA used Flaps 5 at LPB. Is that not correct?
 
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zeke
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Re: More Efficient Takeoff Technique

Sun Feb 04, 2018 8:47 pm

BoeingGuy wrote:
Not totally correct. Only the 767-200 is certified for a Flaps 1 takeoff. The 767-300, 767-400, and KC-46 are not certified for Flaps 1 takeoff. Not sure about the 757 but I don’t believe that it’s certified for a Flaps 1 takeoff either. Put another way, except for the 737, which I’m not as familiar with, all production Boeing airplanes have takeoff flap settings 5-20 as I stated.


This sounded a little odd to me and my suspicions were confirmed. The TCDS and limitations on the 757/767 do not actually say which flap settings are and are not permitted. I think it comes down to what there is published performance data for.

aemoreira1981 wrote:
The Airbus A300 and Airbus A310 are certified for a slats only takeoff, usually used in a hot and high environment (15/0 would be Flaps 1). From a 2003 thread: viewtopic.php?t=734329 However, I don't know if any other Airbus planes can do a slats only takeoff.


All of the Airbus FBW have performance data for Flaps 1 takeoff which is slats and one stage of flaps. You cannot actually select just slats on the ground.
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tb727
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Re: More Efficient Takeoff Technique

Sun Feb 04, 2018 10:51 pm

Max Q wrote:
Correct, that’s why we retracted flaps from
25 to 15 at 400’


That comes up really quick, it was ‘positive rate, gear up’ then almost immediately call for ‘F15’ at 400’


As you say it gets you off the ground in the shortest possible distance but climb rate suffers significantly with the drag of such a high flap setting, so almost immediately after selecting gear up at 400 the flaps would be reduced from 25 to 15


The 727 really wanted to sink with this configuration change and it required a timely application of a significant amount of nose up trim to keep it going uphill at that point and then the climb rate picked up with the huge reduction in drag


It was challenging to practice in the sim, losing an engine while the flaps were still
at 25 required an immediate reduction to 15 while also correcting for the yaw and then the pitch change, fun times


I’m getting all nostalgic and misty eyed. :hearts:
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CanadianNorth
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Re: More Efficient Takeoff Technique

Mon Feb 05, 2018 2:20 am

BWIAirport wrote:
lol dude.. I'm 20, attend a liberal arts college, and my aviation knowledge is limited to what I can find in my free time. Asking questions like this is how I learn. Sorry to waste your time.


I've been working in aviation full time for over 10 years now and I still learn new things from this forum all the time, I thought it was a fair question.

In most cases yes it is a bad idea, just because the vast majority of aircraft have electric or hydraulic flaps that a) have many parts that could potentially malfunction, whether it be binding, leaking, or otherwise; and b) usually take a few seconds to reach the desired setting, which is a good thing because when changing your flap settings in the air you usually have to adjust pitch and/or power, so with the flaps moving at a civilized rate it gives the pilot a chance to keep up on the controls.

However, there are cases where your technique is used regularly... There are many small bush airplanes around, and even some early model Cessna 172s, which have a big old bar in the cockpit directly connected to the flaps. No electrics, no hydraulics, just the pilot's arm muscles. One common "trick" to getting of the ground quickly when on rough terrain and/or tight for distance with some of these bush airplanes is to start flaps up, go full throttle, and then at a given speed reach over and dump some flaps, which creates a sudden increase in lift launching the aircraft into the air. Pretty cool to watch, if you go on YouTube and look up the Valdez STOL competitions you'll see a lot of people trying it.
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Max Q
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Re: More Efficient Takeoff Technique

Mon Feb 05, 2018 3:55 am

tb727 wrote:
Max Q wrote:
Correct, that’s why we retracted flaps from
25 to 15 at 400’


That comes up really quick, it was ‘positive rate, gear up’ then almost immediately call for ‘F15’ at 400’


As you say it gets you off the ground in the shortest possible distance but climb rate suffers significantly with the drag of such a high flap setting, so almost immediately after selecting gear up at 400 the flaps would be reduced from 25 to 15


The 727 really wanted to sink with this configuration change and it required a timely application of a significant amount of nose up trim to keep it going uphill at that point and then the climb rate picked up with the huge reduction in drag


It was challenging to practice in the sim, losing an engine while the flaps were still
at 25 required an immediate reduction to 15 while also correcting for the yaw and then the pitch change, fun times


I’m getting all nostalgic and misty eyed. :hearts:




You and me both TB !
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Siren
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Re: More Efficient Takeoff Technique

Mon Feb 05, 2018 9:07 am

BWIAirport wrote:
lol dude.. I'm 20, attend a liberal arts college, and my aviation knowledge is limited to what I can find in my free time. Asking questions like this is how I learn. Sorry to waste your time.


dude.. pay no heed to the debbie downers. It was a good question that provoked a lively and thoughtful discussion that's bringing out many facts and details we otherwise wouldn't have known. Keep up the good work.

Re: takeoff techniques, I would have thought that the added drag of deployed flaps/slats from a standing start would be minuscule, I'm sure not even a few cents difference in fuel, even if the flats/slats were brought down in time for rotation and liftoff.

Ultimately, the most efficient takeoff technique is using flex/de-rated power, and using as much runway as possible for the conditions. This saves fuel, and also lowers maintenance costs overall. It's not the sexiest method of taking off, but it is the most efficient...
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Max Q
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Re: More Efficient Takeoff Technique

Mon Feb 05, 2018 12:01 pm

Using flex or a derated power setting for take off actually uses more fuel


The aircraft takes longer to get airborne and climbs at a slower rate extending the time it takes to get to altitude where it burns less fuel

It is easier on the engines but it does not burn less fuel
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Starlionblue
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Re: More Efficient Takeoff Technique

Mon Feb 05, 2018 12:11 pm

joffie wrote:
I can imagine it now. 747-400 rolling down the runway with flaps 0, pilots need Flaps 20 for takeoff and by the time the flaps are at 20 plane already at the end of the runway.

Not a good idea. What if the flaps fail to deply? Too many other things to think about during the takeoff run.


For me, this is the core of the poodle. Adding an additional threat (forgetting to set flaps) to an already threat-filled sequence of events seems unwise. The before take-off checklist includes the call "Flap setting" for a good reason.
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RetiredWeasel
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Re: More Efficient Takeoff Technique

Mon Feb 05, 2018 1:51 pm

Oops meant for another tread. Please delete
 
GalaxyFlyer
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Re: More Efficient Takeoff Technique

Mon Feb 05, 2018 4:03 pm

Then there was the KCHS CRJ crew who, sort of, attempted this very idea inadvertently. Data planned for Flaps 20, selected the very normal Flaps 8. During the roll, they tried to extend the Flaps to 20. With the flaps in-transit, they got the take-off warning horn. In the ensuing abort wouldn’t up in the EMAS. Funny part, they didn’t pull the breaker on the CVR allowing their conversation with ALPA to be admissible evidence.

GF
 
N0dak
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Re: More Efficient Takeoff Technique

Mon Feb 05, 2018 5:32 pm

GalaxyFlyer wrote:
Then there was the KCHS CRJ crew who, sort of, attempted this very idea inadvertently. Data planned for Flaps 20, selected the very normal Flaps 8. During the roll, they tried to extend the Flaps to 20. With the flaps in-transit, they got the take-off warning horn. In the ensuing abort wouldn’t up in the EMAS. Funny part, they didn’t pull the breaker on the CVR allowing their conversation with ALPA to be admissible evidence.

GF


That's an interesting one. Unless there was a similar incident, it was at CRW though, not CHS. At my old airline we used it as a teaching point for CRM and decision making.

http://avherald.com/h?article=42607d9d&opt=4096
 
BoeingGuy
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Re: More Efficient Takeoff Technique

Mon Feb 05, 2018 9:31 pm

Max Q wrote:
Using flex or a derated power setting for take off actually uses more fuel


The aircraft takes longer to get airborne and climbs at a slower rate extending the time it takes to get to altitude where it burns less fuel

It is easier on the engines but it does not burn less fuel


That's correct. It's counter-intuitive but derates burn more fuel. Rolls Royce did a study years ago. They said the savings in maintenance cost by doing the slower climb derate washout (10,000-30,000 vs 10,000-12,000 feet) outweighed the additional fuel cost by something like a factor of 7:1. You're running the engine at a lower EGT. Cumulatively, that equates to a lot less wear and tear and maintenance requirements.
 
BoeingGuy
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Re: More Efficient Takeoff Technique

Mon Feb 05, 2018 9:35 pm

Starlionblue wrote:
joffie wrote:
I can imagine it now. 747-400 rolling down the runway with flaps 0, pilots need Flaps 20 for takeoff and by the time the flaps are at 20 plane already at the end of the runway.

Not a good idea. What if the flaps fail to deply? Too many other things to think about during the takeoff run.


For me, this is the core of the poodle. Adding an additional threat (forgetting to set flaps) to an already threat-filled sequence of events seems unwise. The before take-off checklist includes the call "Flap setting" for a good reason.


To Starlionblue's point, Out of Configuration Takeoffs have gotten a lot of industry attention over the years. In fact, one manufacture that I'm familiar with even investigated if you can change the procedure for taxiing in icy slushy conditions. The procedure tells you to delay flap extension so you don't have the possibility of kicking up ice and slush into the flap mechanism when they are extended. Question was raised if this is really an issue - are you really going to kick up slush into the flaps? The concern is having you extend them at the last minute prior to takeoff increases the possibility of rushing and missing it and attempting to takeoff out of config.
 
GalaxyFlyer
Posts: 1162
Joined: Fri Jan 01, 2016 4:44 am

Re: More Efficient Takeoff Technique

Mon Feb 05, 2018 10:27 pm

Yes, KCRW, Charlie West

GF
 
CosmicCruiser
Posts: 2243
Joined: Tue Feb 22, 2005 3:01 am

Re: More Efficient Takeoff Technique

Mon Feb 05, 2018 11:05 pm

forgive me if this was posted as I didn't read all posts. In the jets that I flew you would get the T/O warning horn if you tried to set T/O pwr with flaps 0.
 
BoeingGuy
Posts: 5274
Joined: Fri Dec 10, 2010 6:01 pm

Re: More Efficient Takeoff Technique

Tue Feb 06, 2018 12:51 am

CosmicCruiser wrote:
forgive me if this was posted as I didn't read all posts. In the jets that I flew you would get the T/O warning horn if you tried to set T/O pwr with flaps 0.


I did post this before. On Boeing EICAS (e.g. non-737) models, you get a CONFIG FLAPS warning message and siren if you attempt to takeoff with an invalid takeoff flap setting (1-20 for the 757-200 and 767-200; 5-20 for the others). In addition, the Autothrottlle won't engage for takeoff, as an added level of protection.
 
IPFreely
Posts: 2057
Joined: Sun Dec 24, 2006 8:26 am

Re: More Efficient Takeoff Technique

Tue Feb 06, 2018 1:46 am

stratosphere wrote:
This idea is so idiotic for any number of reasons. Any savings you think you might get by that idea is offset by the increased risk. Takeoff and landing are the most dangerous phases of flight. You do not want to do anything that interferes with any margins in those regimes. As others have said there are plenty of accidents already that attest to the risk. Of course I wouldn't put it past a bean counter to want to suggest it.


You must be a lot of fun at parties.
 
Adispatcher
Posts: 165
Joined: Sun Dec 11, 2016 11:52 pm

Re: More Efficient Takeoff Technique

Sat Feb 10, 2018 3:18 am

BWIAirport wrote:
stratosphere wrote:
This idea is so idiotic for any number of reasons. Any savings you think you might get by that idea is offset by the increased risk. Takeoff and landing are the most dangerous phases of flight. You do not want to do anything that interferes with any margins in those regimes. As others have said there are plenty of accidents already that attest to the risk. Of course I wouldn't put it past a bean counter to want to suggest it.

lol dude.. I'm 20, attend a liberal arts college, and my aviation knowledge is limited to what I can find in my free time. Asking questions like this is how I learn. Sorry to waste your time.


You're not wasting the time of many of us. While some questions may seem mundane, there is always something to learn.

I haven't gone a day at work without learning something. I eavesdrop on coworkers issues just to hear how they are resolved.

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