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ILS28ORD
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737 derated takeoff power question

Thu Apr 25, 2019 10:42 pm

In the 737ng, if a derated engine setting is chosen for takeoff, are the throttle levers advanced full forward for takeoff roll? I'm assuming they are, but then if that's so, how do you select full power?

Ex. 24K lbs thrust is selected for takeoff, on climbout the full 26K lbs is suddenly required, how does the pilot quickly select 26K thrust? If the levers are full forward, Is it just a button on the throttle clicked to enable full power setting and the throttle levers stay at full forward? Or do you need to select 26K via the FMC? Is the TO/GA button used for this function? Thanks for any info.
 
BoeingGuy
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Re: 737 derated takeoff power question

Fri Apr 26, 2019 2:38 am

ILS28ORD wrote:
In the 737ng, if a derated engine setting is chosen for takeoff, are the throttle levers advanced full forward for takeoff roll? I'm assuming they are, but then if that's so, how do you select full power?

Ex. 24K lbs thrust is selected for takeoff, on climbout the full 26K lbs is suddenly required, how does the pilot quickly select 26K thrust? If the levers are full forward, Is it just a button on the throttle clicked to enable full power setting and the throttle levers stay at full forward? Or do you need to select 26K via the FMC? Is the TO/GA button used for this function? Thanks for any info.


No, on Boeing airplanes the Thrust Lever Resolver Angle corresponds to the thrust. So the thrust lever position during derated takeoff thrust would be a little back from full takeoff thrust. You select full power by pushing the thrust levers forward (pilot or auto throttle).

I don’t know the 737 as well, but I’m assuming it works the same as the other models. If you push the TO/GA switch once you are in the air, it will remove the derate and advance the thrust levers forward to full takeoff thrust.
 
ILS28ORD
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Re: 737 derated takeoff power question

Fri Apr 26, 2019 2:56 am

So there is a thrust lever position short of full throttle marked to match the derate setting selected in the FMC prior to takeoff?
 
FlyHossD
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Re: 737 derated takeoff power question

Fri Apr 26, 2019 3:03 am

ILS28ORD wrote:
So there is a thrust lever position short of full throttle marked to match the derate setting selected in the FMC prior to takeoff?


No. The thrust lever position roughly/generally corresponds to the selected thrust. So 85% N1 wouldn't be as far forward as 86%, etc.
My statements do not represent my former employer or my current employer and are my opinions only.
 
ILS28ORD
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Re: 737 derated takeoff power question

Fri Apr 26, 2019 3:24 am

Got it. Thanks. Wasn't sure how that worked. I've been flying the zibo 737-800 in XPlane 11 and saw the derate settings in the FMC but wasn't sure how/where to set my thrust levers. How common are derated T/O's?
 
BoeingGuy
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Re: 737 derated takeoff power question

Fri Apr 26, 2019 3:30 am

ILS28ORD wrote:
Got it. Thanks. Wasn't sure how that worked. I've been flying the zibo 737-800 in XPlane 11 and saw the derate settings in the FMC but wasn't sure how/where to set my thrust levers. How common are derated T/O's?


Very common. I once heard that for some airlines 99% of takeoffs use derated thrust.
 
Max Q
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Re: 737 derated takeoff power question

Fri Apr 26, 2019 4:45 am

Are you referring to Derated or Reduced thrust ?


If you derate an engine to a lower maximum thrust that is the new maximum available thrust, even if you firewall the throttles


You can reduce thrust from a derated engine though and if you want more power / toga will return you to that maximum derated value


Derates are fixed, if you take a 27K
CFM 56 and derate it to 26k that’s the ‘new maximum thrust’ for that engine


A reduced thrust power setting can be removed at any time and converted to full power
The best contribution to safety is a competent Pilot.


GGg
 
ILS28ORD
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Re: 737 derated takeoff power question

Fri Apr 26, 2019 5:01 am

I suppose reduced thrust is what I am referring to. So if an engine is derated it's a permanent performance limitation imposed by a software update in maintenance, and once that's set, you can further use reduced thrust by just advancing the thrust levers as far as needed to reach x% of N1, and push them full forward to reach 100% power, but can't exceed the derate limit set by mechanics?

Is there no FMC setting in a 737 to adjust maximum thrust output available to the pilot?
 
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Starlionblue
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Re: 737 derated takeoff power question

Fri Apr 26, 2019 7:39 am

Many engines are permanently derated. For example on a smaller version of the same jet, (e.g. 736 vs 738) or simply because the airline doesn't need all the performance and pays less. This just means that max thrust is a lower value, and does not affect the above two calculations. You basically just move "100%" to a lower value.

There is another "derate", though. There are two basic ways of taking off with less than the max thrust, or TOGA, for a particular engine.
- Assumed temperature, known as Flex on the 'bus. For engine wear purposes, a lower than maximum take-off thrust is used. At any point during the take-off and climb, TOGA may be selected.
- Derate. For control authority purposes, a lower than maximum thrust is used. Used typically for contaminated runway operations. By reducing the take-off thrust, you can in some cases get better runway performance by reducing Vmcg, ensuring you have enough authority in case of an engine out. With this method, TOGA may not be selected during the take-off because rudder authority can be exceeded.

Assumed temperature or Derate are entered in the FM and are targets for thrust setting. The autothrottle/autothrust will set the thrust to the specified value in the FM. Or you can set it manually, I suppose.

Maximum thrust available to the pilot is always TOGA.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
BoeingGuy
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Re: 737 derated takeoff power question

Fri Apr 26, 2019 3:52 pm

Max Q wrote:
Are you referring to Derated or Reduced thrust ?


If you derate an engine to a lower maximum thrust that is the new maximum available thrust, even if you firewall the throttles


You can reduce thrust from a derated engine though and if you want more power / toga will return you to that maximum derated value


Derates are fixed, if you take a 27K
CFM 56 and derate it to 26k that’s the ‘new maximum thrust’ for that engine


A reduced thrust power setting can be removed at any time and converted to full power


I understand you are referring to a permanent derate, but I don’t think that’s what the OP is asking. I think of the fixed derate (TO 1 and TO 2) as being “derates”. Of course, you can remove the derate by pushing the thrust levers forward or pushing TO/GA on some models. (You aren’t supposed to do this though).
 
ILS28ORD
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Re: 737 derated takeoff power question

Fri Apr 26, 2019 4:50 pm

BoeingGuy wrote:
Max Q wrote:
Are you referring to Derated or Reduced thrust ?


If you derate an engine to a lower maximum thrust that is the new maximum available thrust, even if you firewall the throttles


You can reduce thrust from a derated engine though and if you want more power / toga will return you to that maximum derated value


Derates are fixed, if you take a 27K
CFM 56 and derate it to 26k that’s the ‘new maximum thrust’ for that engine


A reduced thrust power setting can be removed at any time and converted to full power


I understand you are referring to a permanent derate, but I don’t think that’s what the OP is asking. I think of the fixed derate (TO 1 and TO 2) as being “derates”. Of course, you can remove the derate by pushing the thrust levers forward or pushing TO/GA on some models. (You aren’t supposed to do this though).


You're right that's what I was originally asking, however all of this has been helpful information to know. Thanks for the replies.

So then my next question, are all the 737 operators in the US using 26K thrust rated engines or are there lower derated engines mixed into the 737 fleets (24k, 22k)?
 
AABusDrvr
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Re: 737 derated takeoff power question

Sat Apr 27, 2019 1:43 am

ILS28ORD wrote:
BoeingGuy wrote:
Max Q wrote:
Are you referring to Derated or Reduced thrust ?


If you derate an engine to a lower maximum thrust that is the new maximum available thrust, even if you firewall the throttles


You can reduce thrust from a derated engine though and if you want more power / toga will return you to that maximum derated value


Derates are fixed, if you take a 27K
CFM 56 and derate it to 26k that’s the ‘new maximum thrust’ for that engine


A reduced thrust power setting can be removed at any time and converted to full power


I understand you are referring to a permanent derate, but I don’t think that’s what the OP is asking. I think of the fixed derate (TO 1 and TO 2) as being “derates”. Of course, you can remove the derate by pushing the thrust levers forward or pushing TO/GA on some models. (You aren’t supposed to do this though).


You're right that's what I was originally asking, however all of this has been helpful information to know. Thanks for the replies.

So then my next question, are all the 737 operators in the US using 26K thrust rated engines or are there lower derated engines mixed into the 737 fleets (24k, 22k)?



The 73 is a little different in takeoff power selection, than any other airplane I've flown. All of our NG's are 27K engines, but 26K is the "normal" maximum thrust. You can select 22/24/26K via the FMC, and then you can enter an assumed temperature, to further reduce the thrust. For example, today, departing 22L at ORD we had a 24K, 32 deg C reduced thrust takeoff planned. We ended up with a little tailwind, so after crunching the numbers, we removed the 32C derate, and used 24K full thrust. I could have also elected to use 26K full thrust (after getting new thrust data and V speeds via ACARS). At 26K we could have also gone with the engine bleeds off, to increase the thrust and performance a little more.

At a few select airports, we can also use a 27K "bump" takeoff. But I cant request the data for that, it has to be planned by dispatch, and they have to send me the numbers. 27K is always full thrust (no assumed temperature) and most often bleeds off.

ETA: It's worth noting, that on the 73, all the thrust reduction/derating or whatever you would like to call it, is done electronically through the FMC and EEC's. All it does is set the target N1, either the carets on the N1 gauges that you would use if manually setting the thrust, or the auto throttle target N1. The engines are always capable of producing full rated thrust. If you push the throttles to the stops, you will always get 27K. Or as close to it as the ambient conditions will allow.
 
ILS28ORD
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Re: 737 derated takeoff power question

Sat Apr 27, 2019 2:55 am

AABusDrvr wrote:
ILS28ORD wrote:
BoeingGuy wrote:

I understand you are referring to a permanent derate, but I don’t think that’s what the OP is asking. I think of the fixed derate (TO 1 and TO 2) as being “derates”. Of course, you can remove the derate by pushing the thrust levers forward or pushing TO/GA on some models. (You aren’t supposed to do this though).


You're right that's what I was originally asking, however all of this has been helpful information to know. Thanks for the replies.

So then my next question, are all the 737 operators in the US using 26K thrust rated engines or are there lower derated engines mixed into the 737 fleets (24k, 22k)?



The 73 is a little different in takeoff power selection, than any other airplane I've flown. All of our NG's are 27K engines, but 26K is the "normal" maximum thrust. You can select 22/24/26K via the FMC, and then you can enter an assumed temperature, to further reduce the thrust. For example, today, departing 22L at ORD we had a 24K, 32 deg C reduced thrust takeoff planned. We ended up with a little tailwind, so after crunching the numbers, we removed the 32C derate, and used 24K full thrust. I could have also elected to use 26K full thrust (after getting new thrust data and V speeds via ACARS). At 26K we could have also gone with the engine bleeds off, to increase the thrust and performance a little more.

At a few select airports, we can also use a 27K "bump" takeoff. But I cant request the data for that, it has to be planned by dispatch, and they have to send me the numbers. 27K is always full thrust (no assumed temperature) and most often bleeds off.

ETA: It's worth noting, that on the 73, all the thrust reduction/derating or whatever you would like to call it, is done electronically through the FMC and EEC's. All it does is set the target N1, either the carets on the N1 gauges that you would use if manually setting the thrust, or the auto throttle target N1. The engines are always capable of producing full rated thrust. If you push the throttles to the stops, you will always get 27K. Or as close to it as the ambient conditions will allow.


That is the exact answer I was looking for! Thanks. I was seeing 26k/24/22 in the xp11 zibo 737-800's FMC and unsure of where those settings would be demarcated on the instruments or how to set thrust levers to maintain the selected FMC thrust setting. Not easy trying to firgure all of this out on your own..

If you switch engine bleed off for max T/O thrust, how far into the climb would you switch the engine bleed back on? Is it required for air conditioning and pressurization of the cabin?
 
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Starlionblue
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Re: 737 derated takeoff power question

Sat Apr 27, 2019 3:19 am

I'll hazard a guess that 'Boeing is similar to Airbus. The bleeds can go back on once climb thrust is set since you're then no longer be at the thrust limit.

The bleeds are needed for air conditioning and pressurisation so there's a time limit on how long they can stay off.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
AABusDrvr
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Re: 737 derated takeoff power question

Sat Apr 27, 2019 11:25 pm

ILS28ORD wrote:
AABusDrvr wrote:
ILS28ORD wrote:

You're right that's what I was originally asking, however all of this has been helpful information to know. Thanks for the replies.

So then my next question, are all the 737 operators in the US using 26K thrust rated engines or are there lower derated engines mixed into the 737 fleets (24k, 22k)?



The 73 is a little different in takeoff power selection, than any other airplane I've flown. All of our NG's are 27K engines, but 26K is the "normal" maximum thrust. You can select 22/24/26K via the FMC, and then you can enter an assumed temperature, to further reduce the thrust. For example, today, departing 22L at ORD we had a 24K, 32 deg C reduced thrust takeoff planned. We ended up with a little tailwind, so after crunching the numbers, we removed the 32C derate, and used 24K full thrust. I could have also elected to use 26K full thrust (after getting new thrust data and V speeds via ACARS). At 26K we could have also gone with the engine bleeds off, to increase the thrust and performance a little more.

At a few select airports, we can also use a 27K "bump" takeoff. But I cant request the data for that, it has to be planned by dispatch, and they have to send me the numbers. 27K is always full thrust (no assumed temperature) and most often bleeds off.

ETA: It's worth noting, that on the 73, all the thrust reduction/derating or whatever you would like to call it, is done electronically through the FMC and EEC's. All it does is set the target N1, either the carets on the N1 gauges that you would use if manually setting the thrust, or the auto throttle target N1. The engines are always capable of producing full rated thrust. If you push the throttles to the stops, you will always get 27K. Or as close to it as the ambient conditions will allow.


That is the exact answer I was looking for! Thanks. I was seeing 26k/24/22 in the xp11 zibo 737-800's FMC and unsure of where those settings would be demarcated on the instruments or how to set thrust levers to maintain the selected FMC thrust setting. Not easy trying to firgure all of this out on your own..

If you switch engine bleed off for max T/O thrust, how far into the climb would you switch the engine bleed back on? Is it required for air conditioning and pressurization of the cabin?


Yes, the engine bleeds are required for pressurization.

Ideally for a bleeds off takeoff, we would have the APU running, and the APU bleed supplying the left pack ( isolation valve closed). After takeoff, and the thrust reduction to climb thrust (usually 1000’ above the ground) the right bleed is turned on, and the APU bleed turned off. When the cabin rate of climb stabilizes, the left bleed is turned on, the isolation valve goes back to auto, and you shut down the APU.
 
BoeingGuy
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Re: 737 derated takeoff power question

Sun Apr 28, 2019 7:44 pm

AABusDrvr wrote:
ILS28ORD wrote:
AABusDrvr wrote:


The 73 is a little different in takeoff power selection, than any other airplane I've flown. All of our NG's are 27K engines, but 26K is the "normal" maximum thrust. You can select 22/24/26K via the FMC, and then you can enter an assumed temperature, to further reduce the thrust. For example, today, departing 22L at ORD we had a 24K, 32 deg C reduced thrust takeoff planned. We ended up with a little tailwind, so after crunching the numbers, we removed the 32C derate, and used 24K full thrust. I could have also elected to use 26K full thrust (after getting new thrust data and V speeds via ACARS). At 26K we could have also gone with the engine bleeds off, to increase the thrust and performance a little more.

At a few select airports, we can also use a 27K "bump" takeoff. But I cant request the data for that, it has to be planned by dispatch, and they have to send me the numbers. 27K is always full thrust (no assumed temperature) and most often bleeds off.

ETA: It's worth noting, that on the 73, all the thrust reduction/derating or whatever you would like to call it, is done electronically through the FMC and EEC's. All it does is set the target N1, either the carets on the N1 gauges that you would use if manually setting the thrust, or the auto throttle target N1. The engines are always capable of producing full rated thrust. If you push the throttles to the stops, you will always get 27K. Or as close to it as the ambient conditions will allow.


That is the exact answer I was looking for! Thanks. I was seeing 26k/24/22 in the xp11 zibo 737-800's FMC and unsure of where those settings would be demarcated on the instruments or how to set thrust levers to maintain the selected FMC thrust setting. Not easy trying to firgure all of this out on your own..

If you switch engine bleed off for max T/O thrust, how far into the climb would you switch the engine bleed back on? Is it required for air conditioning and pressurization of the cabin?


Yes, the engine bleeds are required for pressurization.

Ideally for a bleeds off takeoff, we would have the APU running, and the APU bleed supplying the left pack ( isolation valve closed). After takeoff, and the thrust reduction to climb thrust (usually 1000’ above the ground) the right bleed is turned on, and the APU bleed turned off. When the cabin rate of climb stabilizes, the left bleed is turned on, the isolation valve goes back to auto, and you shut down the APU.


Some models of 777 will do all this automatically for you, except turn off the APU. It’s called APU-to-Pack Takeoff. You select it where you would enter your Assumed Temperature on the THRUST LIM page.
 
dr1980
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Re: 737 derated takeoff power question

Sat May 18, 2019 2:11 pm

How do pilots physically handle the throttles in an assumed temperature takeoff? In flight sim I will push the throttle levers to around 40% N1, let the engines stabilize, then hit the toga button and push the throttle levers all the way forward. In the PMDG 737 it will select the proper N1 setting based on my assumed temperature. Now of course I don’t have a motorized throttle (I can only dream) so for me the throttles stay all the way forward through the flight although the animated throttles in the sim move as needed.

What position would the real world pilots move the throttles to after hitting toga and before letting the auto throttle take over their movement? In the A320 there are set detent but to my knowledge there are none in the 737NG.

Thanks!
Dave/CYHZ
 
Passedv1
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Re: 737 derated takeoff power question

Sat May 18, 2019 4:32 pm

First you decide what thrust setting/assumed temp you will use for this take off. This requirement depends.on weight, environmental variables, etc. After you determine what combination you are going to use, you punch that into the FMC. Say 24k thrust with an A/T of 38c. The FMC then takes this and calculates an N1 that is used as the t/o power setting...say 87.6%.

Somebody on here stated that if you firewall the engines you will get the de-rated thrust, in this case 24k, that is not true. You will actually get slightly more than the permanent rated thrust of the engines that are installed on the airplane. If you have 27k engines installed ...you will get 27k plus a little when you firewall it. If you take off with a de-rated thrust of 24k and you firewall the engines you will get 27k+ of thrust. The debate that you are entering in the FMC only moves the red lines on the instruments, they do not effect the actual performance of the engine.

Before somebody comes on here and rips my head off about the fact that 24k engines are 27k engiens etc. I will just pre-empt you and say that as a pilot I understand that but I dont care much about that because I cannot change that value in flight. All I need to know is that if Ifirewall the thrust levers I will get slightly more than the installed thrust rating of the airplane.
 
BoeingGuy
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Re: 737 derated takeoff power question

Sat May 18, 2019 8:17 pm

dr1980 wrote:
How do pilots physically handle the throttles in an assumed temperature takeoff? In flight sim I will push the throttle levers to around 40% N1, let the engines stabilize, then hit the toga button and push the throttle levers all the way forward. In the PMDG 737 it will select the proper N1 setting based on my assumed temperature. Now of course I don’t have a motorized throttle (I can only dream) so for me the throttles stay all the way forward through the flight although the animated throttles in the sim move as needed.

What position would the real world pilots move the throttles to after hitting toga and before letting the auto throttle take over their movement? In the A320 there are set detent but to my knowledge there are none in the 737NG.

Thanks!


On all Boeing airplanes, the procedure is to manually advance the thrust levers partway (such as 55 N1 or 1.05 EPR) to let the engines stabilize and make sure everything is coming up symmetrically. Then push TO/GA to engage the Auto-throttle to the selected takeoff thrust. The Autothrottle will advance the thrust levers forward. The Captain will then put his or her hand on the thrust levers to guard them in case they decide to reject the takeoff.

The 757 and 767-200/-300 instead use the THR Switch on the Mode Control Panel to engage the Autothrottle for takeoff, but everything else I described is the same. (The 767-400 and KC-46 do use the TO/GA switch to engage takeoff thrust.)
 
dr1980
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Re: 737 derated takeoff power question

Sat May 18, 2019 10:33 pm

Thanks!
Dave/CYHZ
 
Redbellyguppy
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Re: 737 derated takeoff power question

Sun May 19, 2019 5:00 am

In my 737 autothrottles are armed prior to taking the runway. When cleared for takeoff I advance the thrust to 40% N1 until everything stabilizes. Then when I press TOGA the autothrottle advances the thrust levers to the FMC programmed setting. I could do this manually if the AT is deferred by moving the thrust levers until the N1 pointers match the “>” indication that depicts the target N1 setting for takeoff thrust.
 
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Starlionblue
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Re: 737 derated takeoff power question

Sun May 19, 2019 7:01 am

dr1980 wrote:
How do pilots physically handle the throttles in an assumed temperature takeoff? In flight sim I will push the throttle levers to around 40% N1, let the engines stabilize, then hit the toga button and push the throttle levers all the way forward. In the PMDG 737 it will select the proper N1 setting based on my assumed temperature. Now of course I don’t have a motorized throttle (I can only dream) so for me the throttles stay all the way forward through the flight although the animated throttles in the sim move as needed.

What position would the real world pilots move the throttles to after hitting toga and before letting the auto throttle take over their movement? In the A320 there are set detent but to my knowledge there are none in the 737NG.

Thanks!


Thrust levers. They are thrust levers, not "throttles". :)

I think the term "throttle(s)" is only be used by the military.

The automatic function is called "autothrottle" on Boeing, for some unfathomable reason that I presume has to do with tradition and history. On Airbus the perhaps more logical "Autothrust" is used.

#nomenclaturepedant
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
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AirKevin
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Re: 737 derated takeoff power question

Sun May 19, 2019 1:56 pm

Starlionblue wrote:
dr1980 wrote:
How do pilots physically handle the throttles in an assumed temperature takeoff? In flight sim I will push the throttle levers to around 40% N1, let the engines stabilize, then hit the toga button and push the throttle levers all the way forward. In the PMDG 737 it will select the proper N1 setting based on my assumed temperature. Now of course I don’t have a motorized throttle (I can only dream) so for me the throttles stay all the way forward through the flight although the animated throttles in the sim move as needed.

What position would the real world pilots move the throttles to after hitting toga and before letting the auto throttle take over their movement? In the A320 there are set detent but to my knowledge there are none in the 737NG.

Thanks!


Thrust levers. They are thrust levers, not "throttles". :)

I think the term "throttle(s)" is only be used by the military.

The automatic function is called "autothrottle" on Boeing, for some unfathomable reason that I presume has to do with tradition and history. On Airbus the perhaps more logical "Autothrust" is used.

#nomenclaturepedant

But if the thrust levers move automatically on a Boeing jet, wouldn't that make it the "autothrustlever"?
Captain Kevin
 
dr1980
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Re: 737 derated takeoff power question

Sun May 19, 2019 1:56 pm

I thought I had that wrong as I was typing it :)
Dave/CYHZ
 
AABusDrvr
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Re: 737 derated takeoff power question

Sun May 19, 2019 4:45 pm

Starlionblue wrote:
dr1980 wrote:
How do pilots physically handle the throttles in an assumed temperature takeoff? In flight sim I will push the throttle levers to around 40% N1, let the engines stabilize, then hit the toga button and push the throttle levers all the way forward. In the PMDG 737 it will select the proper N1 setting based on my assumed temperature. Now of course I don’t have a motorized throttle (I can only dream) so for me the throttles stay all the way forward through the flight although the animated throttles in the sim move as needed.

What position would the real world pilots move the throttles to after hitting toga and before letting the auto throttle take over their movement? In the A320 there are set detent but to my knowledge there are none in the 737NG.

Thanks!


Thrust levers. They are thrust levers, not "throttles". :)

I think the term "throttle(s)" is only be used by the military.

The automatic function is called "autothrottle" on Boeing, for some unfathomable reason that I presume has to do with tradition and history. On Airbus the perhaps more logical "Autothrust" is used.

#nomenclaturepedant


On the MD-80 they were throttles in all the our manuals.
 
LH707330
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Re: 737 derated takeoff power question

Mon May 20, 2019 4:55 pm

Technically, "thrust lever" makes more sense (although why "lever" and not "handle?" I think a lot of it could just be nomenclature history and regional differences, same way we got cockpit/flightdeck, reheat/afterburner, etc.
 
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Starlionblue
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Re: 737 derated takeoff power question

Wed May 22, 2019 7:46 am

AirKevin wrote:
Starlionblue wrote:
dr1980 wrote:
How do pilots physically handle the throttles in an assumed temperature takeoff? In flight sim I will push the throttle levers to around 40% N1, let the engines stabilize, then hit the toga button and push the throttle levers all the way forward. In the PMDG 737 it will select the proper N1 setting based on my assumed temperature. Now of course I don’t have a motorized throttle (I can only dream) so for me the throttles stay all the way forward through the flight although the animated throttles in the sim move as needed.

What position would the real world pilots move the throttles to after hitting toga and before letting the auto throttle take over their movement? In the A320 there are set detent but to my knowledge there are none in the 737NG.

Thanks!


Thrust levers. They are thrust levers, not "throttles". :)

I think the term "throttle(s)" is only be used by the military.

The automatic function is called "autothrottle" on Boeing, for some unfathomable reason that I presume has to do with tradition and history. On Airbus the perhaps more logical "Autothrust" is used.

#nomenclaturepedant

But if the thrust levers move automatically on a Boeing jet, wouldn't that make it the "autothrustlever"?


They're only "auto" when they're moved by the autothrust, so IMHO thrust lever and autothrust are fine. But I don't write the manuals. :D
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