View Full Version : T/o and ldg flap setting on 737NG

6th Feb 2008, 20:06
Hi everybody,
I'm looking for colleagues that work in an airline that uses flaps 1 for t/o and flaps 15 for ldg during NORMAL ops. Actually where I am, we use respectively F5 and F30 but management is considering this change concerning fuel savings and environnemental issue.
Thanks for your inputs.:ok:

FCS Explorer
7th Feb 2008, 00:03
we do F1-T/Os. for landing we can choose btw 30 & 40. 40 also better for shorter rwy of course.
what exactly is your question?

7th Feb 2008, 08:25
737Jock - it has been pointed out before that the wording from Boeing describes F15 as a 'normal' landing setting ('JAA excluded') - it is just that very few people actually use it and it would only apply where 2 engine g/a performance is degraded - ie hot and/or high? I find the use of the word 'normal' by Boeing there misleading, but technically it is correct - have a look in the FTM - page 4.44 in mine.

EDIT small typo

17th Oct 2009, 13:19
I've used F15 landing in very nasty/turbulent landing scenarios (usually involving significant wind additives) as it lends itself to greater FLAP OVERSPEED margins during those gusts that are encountered during approach. F40 would certainly be out of the question because of the tighter margins associated with wind additives and lower overspeed constraints...lastly, do you really want your flaps retracting as you bust through the limits for blowup F30 or F40 with the gust factor?
Very good to practice F15 since that attitude is slightly different and will be used with an engine failure.

17th Oct 2009, 13:58
The 737-6/7/800 AFM (Doc D631A001) states in Section 1 Limitations:

Flaps 15 normal landings are prohibited.

Your AFM may be different, but best you check your FCOM Vol 1 (Limitations - Flight Controls) or with your fleet office before electing to do a flap 15 landing unless you have a non-normal which calls for it.

17th Oct 2009, 15:39
Captain S - has the the NG FCTM October 31, 2002 been superceded?

Page 4.44
Landing Configurations and Speeds
Flaps 15 (except JAA), 30 (for noise abatement) and 40 are normal landing flap
positions. Flaps 15 is normally limited to airports where approach climb
performance is a factor. Runway length and condition must be taken into account
when selecting a landing flap position.

17th Oct 2009, 16:07
Our manual states Flaps 15 normal landings are prohibited. as well, however it is boeing tailored for EU-OPS operation which might explain that.

Take-Off flap settings are 25, 15, 10, 5 and 1. Normally used is 1 and 5, the higher flap settings are selected by the boeing performance tool depending on aircraft certification status and runway limits.

17th Oct 2009, 16:43
Evidently, (US Major) FCTM and Vol I have no limitations to F15 normal landing...a couple notes apply: remember Flap Override sw. as you configure and a note to bump Vref up if Anti-ice used...not to exceed Vref+20 (VrefICE=Vref+10)....flys like a dream in the choppy/turbulent conditions...some even swear a more consistant smooth landing!

17th Oct 2009, 18:38
Further for Captain S - I have kindly been sent the Oct 2008 NGFCTM (thanks!) which also says the same? Now confused!

17th Oct 2009, 21:00
T.O. - 1, 5, 15
Ldg - 15, 30, 40.

Obviously different carriers have different restrictions/SOP's.

FE Hoppy
17th Oct 2009, 22:06
Not uncommon for JAA/FAA limitations to differ.

On the E-jets the go around flap setting is different for JAA or FAA certified aircraft which was funny for the airline in OZ that had some with JAA AFM and others with FAA AFM.

IT's of course the AFM that counts not the FCTM/AOM

17th Oct 2009, 23:21
IT's of course the AFM that counts not the FCTM/- absolutely, but isn't it a little STRANGE to have a difference like that from the same company?

18th Oct 2009, 01:02
One would assume that regular F15 landings would induce extra brake wear, but how would this compare in cost to the extra fuel burned for F30 or 40 landings...:bored:

18th Oct 2009, 07:58
Brake wear might be a consideration, break temperatures on constantly minimum time turnarounds however surely are. And the differences in speed by using higher flap settings make quite a difference. Of course the differences in variants is even bigger, so flying into a limiting field with a -700 is quite pleasant, with an -800 it can ruin your minimum turnaround.

I do not know why EU-OPS 737s are not allowed to used flaps 15 though, i'm kinda puzzled by that to be honest. Strange however that up to 25 for take off seems to be a rare thing too.

18th Oct 2009, 09:49
A pal of mine who flies the 737NG in Korea wrote to me after my post above to say that they were on FAA rules and their AFM allowed F15 landings. So it seems to be that FAA AFMs allow it but JAA AFMs donít, the question is why the difference?

The usual reason for extra permissions, eg 10 min take-off thrust or 15kt tailwind landing etc, is because an operator has requested it after the initial certification. Boeing has then certified it and either sold it to them as an AFM supplement or incorporated it into the body of the next AFM. I suspect what happened here is that an operator on the FAA AFM wanted to operate into hot & high airfields (eg Ulaanbator, La Paz), Boeing approved it and put it in the FAA AFM. Since no JAA operators had made the request they saved their money and left the JAA AFM alone, maybe hoping that they can sell the AFM change to anybody that asks for the appropriate fee. Or am I being too cynical?

18th Oct 2009, 11:42
In case of differences the FCOM has precedence over the FCTM.
We operate under EU-OPS and the FCTM states:
" 737-300 : Flaps 15,30 (for noise abatement ) and 40 are the normal landing positions. Flaps 15 is normally limited to airports where approach climb performance is a factor.

737-NG : Flaps 15 ( except JAA ), 30 (for noise abatement) and 40 are normal landing positions....'
Interesting difference between Classic and NG.

The FCOM for the Classic has no limitation for Flap 15 but the NG has : " Flap15 normal landings are prohibited. A flap 15 landing may be performed when required by a non-normal procedure"

So, with a 300 can be done , but not with a 700? Interesting..

18th Oct 2009, 13:44
It's been a long time since I've flown the 737....and, I flew the -200 (both Basic and Advanced), the -300, and the -400.

As I recall, on the -400, Flaps 1 takeoffs were not certified due to the possibility of tail strike.

I have no knowledge of 737s after the -400, especially the new 'NG' models.

Regarding the use of Flaps 15 for landing, it was (on the aircraft I flew) a legal flap setting for landing. However, my company's SOP called for....
normally....using Flaps 30 for noise and fuel economy reasons. But, under certain conditions, at the captain's discretion, Flaps 40 could be used. Some guys used Flaps 40 almost all the time, as they didn't give a XXXX about saving fuel or making noise. Flaps 15 was reserved for non-normal situations. But, again, it was legal to use Flaps 15 for landing under normal conditions. And, again, some guys liked to do it now and again, just for practice.

It's interesting to note that legal flap settings may be outside your company's SOP. Or, you may not have 'the numbers' for certain flap settings. As an example, Flaps 2 may provide optimal takeoff performance, but you may not have performance charts to validate this.
(Obviously, you have to have the published charts to use any particular flap setting for takeoff....or landing, for that matter.) Flaps 2 may provide the best accelerate/stop performance, and, at the same time, provide the best single-engine climb gradient should you experience an engine failure at V1 or after. But, again, without the charts to prove it, you cannot use it. And, again, on the -400, I'm thinking Flaps 5 was the least flap setting you could use, due to tailstrike issues.

Boeing certifies (through the FAA) many different flap settings for takeoff and landing. You may not know this, as your company does not allow this or that....or does not publish numbers for these settings. For example, on the airplanes I flew, it was a legal flap setting to takeoff with Flaps 25. If I recall, Boeing came up with the certification numbers for this so some operators could use the aircraft in and out of unimproved strips.

Again, I don't know anything about the new 'NG' series. Some of these new 737s are quite long, and tailstrike issues are a concern. This may limit takeoff flaps to Flaps 5 or greater....and landing flaps to Flaps 25 or 30 or greater. (Leaving Flaps 15 landings only for non-normals.) Again, I don't know. As always, you company's SOP is the 'Bible'.

Fly safe,