What does the POH say about flap settings?

[Trey Kule]

I was sitting with a group of pilots today, who were in a discussion about flap setting changes for wind, on smaller GA aircraft.
The general consensus amongst this very experienced group is they land using the landing flap setting.
I will not go into their arguments for not reducing the flap settings because of wind, but I am curious what the actual POHs have to say


When I read some forum threads, it appears that pilots in training are taught to land in stronger winds with a reduced flap setting.


I am not interested, per se, in a discussion on the techniques of landing in strong winds or crosswinds, but I am curious as to what the POH's for aircraft like the 172, cirrus , diamond singles etc., actually have to say about this.


If anyone has a POH, or can reliably quote I would like to hear what the POH's have to say about this. Please not the type referenced.

[Liquid Charlie]

Pulling it out of my ass but I would suspect there is nothing said. Having said that who reads POH on light aircraft -- haha -- damn I'm showing my age cuz I never saw a POH for a cub which I learned to fly on and oh ya -- what the fuck is a POH and old guy can't keep up with acronyms. I can remember my first ALPA meeting -- I had to have google up and running just to figure out what the fuck they were talking about --


Flap settings for landing is an elusive subject. I personnaly and a "landing" flap kinda guy -- even in extreme xwinds I always used normal flap settings but have sat and watched while guys use reduced flaps -- my reasoning - changes attitude and in my mind why would you want a better performing wing so I'm firm in the land flap school -- and yes this goes for conventional gear as well --

[Chris]

My 1975 172M POH says that landings may be made with any flap setting desired, but recommends avoiding steep slips with more than 20 degrees due to possible pitch oscillations (which I've never noticed even with 40 degrees).

[Trey Kule]

.
Thanks Chris.

Anybody out there have a POH that specifically states to use reduced flaps to land in stronger winds?

I do not have TC's FTM , but FTGU,** which I have access to...Asks the question:
** (for you, Liquid C.  Acronyms to read..We all know what the F stands for , right)
"How much flap should be used in landing?"

Full flaps......but they also mention experience, C of G etc as being factors, as well as "unfavourable winds"
Then they speak of inadvisability of using full flaps in crosswinds due to control problems "on the ground"...that is the landing roll.

But nothing, it seems other than a reference to experience about landing with less than full flaps in stronger winds where there is not a x-wind factor.

It is puzzling that very high time pilots use landing flaps almost 100% of the time, but it seems student pilots are being taught something different...I am genuinely curious.
Any instructors want to weigh in on this?

[BCPilotguy]

My POH (Cherokee C) says a couple things about it.


[quote]The amount of flap used during landings and the speed of the aircraft at contact with the runway should be varied according to the landing surface, and existing conditions both windwise and loadwise.[/quote]


[quote]In high wind conditions, particularly in strong cross winds, it may be desirable to approach the ground at higher than normal speeds, with partial or no flaps.[/quote]


I use full flaps up to around 25-30 knots of wind. Above that I don't use flaps at all, I've never landed with partial flaps.

[quote author=Chris link=topic=5846.msg15293#msg15293 date=1489585291]
My 1975 172M POH says that landings may be made with any flap setting desired, but recommends avoiding steep slips with more than 20 degrees due to possible pitch oscillations (which I've never noticed even with 40 degrees).

[font=Verdana][/font][/quote][font=Verdana][/font]


Back when I was renting I managed to get the 172 to buck only once. It would definitely get your attention if you weren't expecting it but it's not [i]that[/i] dramatic.

[Trey Kule]

A bit of drift here, but if the POH says it is not recommended to do something, like side slip with full flaps, why would you try it?  It may be that one day the CG will be different and you will get a very nasty surprise.
Actually, I am a bit surprised that at least two of you have tried it despite what the POH says.

[BCPilotguy]

[quote author=Trey Kule link=topic=5846.msg15302#msg15302 date=1489636789]
A bit of drift here, but if the POH says it is not recommended to do something, like side slip with full flaps, why would you try it?  It may be that one day the CG will be different and you will get a very nasty surprise.
Actually, I am a bit surprised that at least two of you have tried it despite what the POH says.
[/quote]


"Not Recommended" isn't the same thing as prohibited. This is the actual wording:
[quote]Steep slips should be avoided with flap settings greater than 20 degrees due to a slight tendency for the elevator to oscillate under certain combinations of airspeed, sideslip angle, and center of gravity loadings.[/quote]
I actually had an instructor tell me to do it on a rental checkout once (a bit high on a simulated forced approach, needed just a bit more drag to get it down. It worked.). It's not dangerous, the oscillation is just that, and it's not a common occurrence anyway. It's just surprising if you aren't looking out for it. The one time I managed to get the oscillation I had to dick around quite a bit to make it happen. I like to explore the operating envelope of any airplane I'm flying, and unless there's a specific prohibition I see no reason not to try any maneuver the airplane is certified for.

[David MacRay]

My copy of the POH for the 172 N model says, "When landing in a strong crosswind, use the minimum flap setting required for the field length."

I'll post a picture if me and the attachment setting can get along better.

[Trey Kule]

Beef: Interesting, although its a x-wind situation and not just a stronger wind. Does the POH give minimum flap settings for different field lengths?

BCPG..I understand what recommended means.  Still do not understand why you would do something that is advised you should avoid.  And because an instructor does it...meaningless.Maybe your instructor should have worked with you to make a proper approach, or helped you to understand when to do a missed instead of an out of the box resolution to a to high approach. From my experience, instructors routinely teach weird and dangerous procedures. (spend some time reading the forums here on doing such things as forced landings starting in cloud, or how to power through a stall without lowering the nose because you are flying a twin) But fill your boots doing things that are not recommended. It is good to learn to dismiss the advice of the manufacturer and continue to expand the flight envelope. Please , though, be a nice guy, and do not do them when you have innocent pax on board or are above anything that will get anyone hurt if things do not go as planned..
For what its worth, the biggest job a CP has in small operations is not pushing pilots to fly, but keeping the young and/or stupid from going out and killing themselves trying some new idea,taking a look, or just doing something they think will be cool.Maybe keep that in mind next time  you think about doing something that is not recommended by the manufacturer.
Because you got away with without any negative consequences does not mean it will work out well every time..And you only have to be unlucky once. Perpetuating the idea that it is benign is encouraging others to do it...So we have the POH advising against it, and pilots who say no biggie...Which do you think the young and vulnerable will listen to. The book, or the mentor?
I apologize for the rant.

So, when it comes to light aircraft, where is everyone getting their knowledge of what flap setting to use in what wind?
(again, not x winds particularly).  How are instructors teaching the conditions where one would reduce the landing flap settings?
If it is just all about experience, then the old guys who land full flap all the time may be on to something, as they only have to learn how to handle the plane in the same configuration each time, and take account of the other factors, rather than change the configuration and respond to the environmental factors. Reduces the variables for decision making.

Has no one a Cirrus, or similar POH?

And where is Cat?

[Chuck Ellsworth]

[quote]And where is Cat?[/quote]


Here.