B738 NG Gear down Flaps 15
Joined: Apr 2008
Posts: 525
Likes: 2
From: Nearer home than before!
I have to admit, flying at altitude in a part of the world that seems to like tailwind approaches....
I'm mostly using flap 10 to help keep the speed in check on at least on approach each day. The SFP can be a pain on those occasions......
I'm mostly using flap 10 to help keep the speed in check on at least on approach each day. The SFP can be a pain on those occasions......
Joined: Jul 2014
Posts: 1
Likes: 0
From: Malabo , Equatorial Guinea
Captain Freire
None of the answers is fully correct.Imagine that you don't wait and you get one red landing gear light.What's your next action? Check-list to try to solve the gear problem.Where is your flaps:15. Which one offers more drag and consequently, more fuel consumption: Flaps 5 or flaps 15? Think about it and you'll see that Boeing is not stupid.There's a board of very experienced pilots preparing the procedures with caution and logic.Take care and follow what's written properly.
Joined: May 2026
Aviation Qualifications: ATPL
Posts: 2
Likes: 0
From: Rhode Island
Some do... Some don't !
I don't... Can't see a reason for waiting.
The "waiting thing" is most common among pilots with a 737-300 background !
If I remember correctly, selecting the flaps without having the landing gear down and locked (green lights) on this type would sound the "Landing Gear Configuration Aural Warning" (which was really annoying), but it could be easily muted (just as on the NG)
I don't... Can't see a reason for waiting.
The "waiting thing" is most common among pilots with a 737-300 background !
If I remember correctly, selecting the flaps without having the landing gear down and locked (green lights) on this type would sound the "Landing Gear Configuration Aural Warning" (which was really annoying), but it could be easily muted (just as on the NG)
However, the key procedural intent remains unchanged:
The gear lever selection and flap 15 selection are still intentionally sequenced with a verification barrier in between, even if the callout is combined.
The PM:
- selects gear DOWN
- confirms three green landing gear indicators
- then selects flaps 15
Why Boeing structures it this way:
The landing gear lever position is only a command to extend, not confirmation of status. The system can still be:- in transit
- asymmetrically extended
- or affected by a malfunction (gear disagree / unsafe indication)
Flap 15 is part of the landing configuration build-up, and Boeing’s intent is to ensure the aircraft is in a verified stable configuration state before further increasing drag and changing energy management characteristics.
Bottom line:
Even though the PF issues a single combined call, the system logic and SOP intent still require:gear status confirmation (three green) before completion of the landing configuration to flaps 15.
Joined: Mar 2007
Posts: 981
Likes: 15
From: Sydney, Australia
Can you ask the AI you got to reguritate this where that intentional sequencing is described in the FCOM/FCTM? I can't find it in my manuals.
Joined: Feb 2003
Posts: 543
Likes: 338
From: Blue sky
To those people reading the FCOM:
When the wording of the FCOM is
*Set the landing gear lever to DN
*Verify that the green landing gear indicator lights are illumated
*Set the flap lever to 15
*Set the engine start switches to continuous"
It does not stop you from doing this in one sequence. The check of landing gear indicator lights does not prohibit you from moving on and setting the flap lever to 15. There is no reason to delay the start switches either.
In the FCOM you will notice that from the moment the engines are started, Boeing asks you to verify lights every time they are not covered by the master caution system. When you start the engines, at some point you will select the packs on. Boeing does not ask you to verify the pack light when you select it, because it will be covered by master caution. When you look at the selection of takeoff flaps, Boeing will ask you to "verify that the LE FLAPS EXT green light is illuminated" in the same way. I've known companies that will ask pilots to wait for the green light before they can do the flight control check which is not necessary. The system is protected. You can continue, however at some point you as a pilot have to do the check to confirm.
Same philosophy with the selection of landing gear, and speedbrake arm on approach. Boeing explicitely asks you to verify the appropriate light as they are not covered by master caution. There is absolutely no need to wait for 3 greens before you can select the next flap position and select continuous ignition.
When the wording of the FCOM is
*Set the landing gear lever to DN
*Verify that the green landing gear indicator lights are illumated
*Set the flap lever to 15
*Set the engine start switches to continuous"
It does not stop you from doing this in one sequence. The check of landing gear indicator lights does not prohibit you from moving on and setting the flap lever to 15. There is no reason to delay the start switches either.
In the FCOM you will notice that from the moment the engines are started, Boeing asks you to verify lights every time they are not covered by the master caution system. When you start the engines, at some point you will select the packs on. Boeing does not ask you to verify the pack light when you select it, because it will be covered by master caution. When you look at the selection of takeoff flaps, Boeing will ask you to "verify that the LE FLAPS EXT green light is illuminated" in the same way. I've known companies that will ask pilots to wait for the green light before they can do the flight control check which is not necessary. The system is protected. You can continue, however at some point you as a pilot have to do the check to confirm.
Same philosophy with the selection of landing gear, and speedbrake arm on approach. Boeing explicitely asks you to verify the appropriate light as they are not covered by master caution. There is absolutely no need to wait for 3 greens before you can select the next flap position and select continuous ignition.
Last edited by BraceBrace; 12th June 2026 at 10:21.
Joined: Dec 1998
Aviation Qualifications: ATPL
Posts: 581
Likes: 412
From: UK
It’s been a long time since I flew the 737 classic. Just checked an old FCOM and F15 only triggers the gear horn with the thrust levers below 30 degrees. It can be silenced with the cutout switch until you have greater than F15. So do 737 operators fly 160/4 with F15 and the gear up? Pretty sure we did to keep the noise and fuel burn down. Seem to remember pressing that button every time the thrust levers came back.
As someone said, the FCOM has to be written somehow - the order sometimes matters, sometimes it doesn’t. In this case it doesn’t in my opinion. So long as you arrive at your stable approach point stable with gear down and landing flap then who cares how you do it provided it’s sensible and not a rushed approach. 3 greens is hopefully checked a second time properly as part of the landing checklist (although it can be automatic response without looking at the indications under high workload)!!
We all strive for low workload approaches but if you do find yourself a bit hot at F5 then gear down flap 15 is a good place to start the recovery. Waiting to select F15 and slow down just wastes time and distance.
And “not overloading the hydraulic system”
Is nonsense.
As someone said, the FCOM has to be written somehow - the order sometimes matters, sometimes it doesn’t. In this case it doesn’t in my opinion. So long as you arrive at your stable approach point stable with gear down and landing flap then who cares how you do it provided it’s sensible and not a rushed approach. 3 greens is hopefully checked a second time properly as part of the landing checklist (although it can be automatic response without looking at the indications under high workload)!!
We all strive for low workload approaches but if you do find yourself a bit hot at F5 then gear down flap 15 is a good place to start the recovery. Waiting to select F15 and slow down just wastes time and distance.
And “not overloading the hydraulic system”
Is nonsense.
Last edited by Propellerhead; 10th June 2026 at 14:28.
Joined: Sep 2016
Posts: 937
Likes: 67
From: USA
I am explaining technically and aerodynamically the aircraft proper landing configuration with both the standard and the SFP NG's ( Never flew classics )
Defined by the position of the LE Slats position in relation to the trailing edge flaps position with the different NG variants , which may clarify the requirement for some variants to select flaps 15 after having three greens and having this as an Airline SOP to stay within the proper Aircraft landing configuration
Which was the question at the beginning of the thread .
Defined by the position of the LE Slats position in relation to the trailing edge flaps position with the different NG variants , which may clarify the requirement for some variants to select flaps 15 after having three greens and having this as an Airline SOP to stay within the proper Aircraft landing configuration
Which was the question at the beginning of the thread .
