Flap retraction during landing roll

ColMustard

ColMustard

New Member
I've heard both sides to this, and I'm kinda in the middle. The question is whether or not to retract the flaps during the landing roll? Furthermore, if not for all cases, should it be taught during private flight training?

I've found that retracting the flaps after the airplane has landed, allows for more effective braking, and a shorter landing distance. On the other hand this may cause a hazard due to distraction during a phase of the flight that requires more concentration, and the possibility in raising the wrong lever in a complex aircraft.

Lemme know what y'all think from your own experience. I'd like to have the CFI's give a shout on whether or not they add this to their training curriculum.

-ColM
 
This might be my imagination again, but I think the FAA frowns on runway configuration changes.
 
I was taught to retract the flaps as soon as practical to help get the weight of the airplane on the wheels ASAP to, as you mentioned, make the brakes more effective.
 
I think it's a good idea to leave the flaps alone. As my examiner pointed out during my CFI checkride, the added braking effect from raising the flaps is negligible. The wings really aren't supporting any weight of the aircraft during the landing roll, especially after touching down in a full stalled condition.
 
My very first CFI when i first started told me to leave the flaps down to help with aerodynamic braking......and the last CFI i had likes to bring em up as soon as possible for the above reasons. guess it depends on who you talk to
 
I teach only to retract flaps on short field landings on the runway, or during touch and go's. Otherwise, leave them out until off the runway.
 
i retract them. in the pa-28-161, the POH calls for flap retraction on touchdown for the landing distance table. i never trusted my students enough to teach this technique.

how about that for a hypocritical answer?
 
Yes, leave things as if unless it is a touch and go or somthing...or some other circumstance which the need to retract them is greater than the need not to....I can think of none right off, but you never know. I mean I am merely in a C152, so it would be kind of hard to confuse it for somthing else, but maybe in a more complex aircraft it may--hey don't think you can't either. I actually almost pulled the mixture out instead of throttle the other day when we were about to go over slow flight with my new CFI--she was seeing where I was since it was my first day with her. I remember her saying, "Wait. What are you doing?" I was thinking, "Uh, you said slow flight? Pulling power out." Then I looked down and said, "Oh. That would not have been good"....even if it was a good practice for engine failure! I mean it is very easy to confuse things...especially when you can do things without looking.
 
If you need to retract the flaps to have adequate stoping distance... don't bother trying your luck with a take off on the same runway!
 
I like to pop the flaps back up just prior to touchdown when doing a short field :). It makes it interesting...(works well in the light Beechcraft aircraft).

To get on topic - during my commerical checkride, the examiner wanted me to bring the flaps up (this was in a Mooney M20J).

Retracting flaps doesn't do much in a light aircraft IMO. To really make your landing roll a lot lower, land on speed. Forcing the plane down on a spot actually makes your landing distance longer than if you held it off and bled the speed down and let it plop on the ground at a slow speed. Sorta like when you're high on the GS, pitching down doesn't help because you pick up speed, but if you slow down and then lower the nose you're in a much better situation (IMO).
 
This is the one procedure that I never abide by no matter what is in the book.

It could be argued that if you need to do that in order to stop on the remaining runway, then you shouldn't be landing on that runway at all. More importantly, why try to fly the airplane and do something else at the same time if you don't have to? Just keep it on centerline, get it slowed down, and taxi off the runway. Then do the after landing check. Landing an airplane and retracting flaps immediately after touchdown is a lot like switching lanes in heavy traffic while talking on your cell phone.

A completely different reason to not retract the flaps is that you could accidently reach for the landing gear knob if the plane has one.

Flaps full is more drag than lift, then halfway is some lift and drag, and flaps to the first notch is a lot of lift but not much drag. When you retract the flaps at 50 knots groundspeed on your 152/172 etc. you first eliminated a lot of drag, and then a few seconds later, when you're already down to probably 30 knots, you do lose some lift. At that point you're not getting much lift at all, flaps or not.

Fly the airplane.
 
Everybody else has given a pretty good summary of why you should or should not retract flaps on the runway.

All I can add is something a friend of mine told me a while ago. He does a fair amount of Idaho backcountry flying in his 182. He said when he's going into narrow (say, 30 feet wide or less) and short (say, less than 1500 feet) strips in the mountains, retracting flaps on touchdown is the last thing on his mind. He's much more concerned about staying in the center of the landing surface and doesn't worry about any extra braking action he could get.

Take that for whatever it's worth.
 
I've got quite the "nasty" habit of retracting them while on the landing roll out. You can feel a significant amount of weight of the plane drop onto the wheels in a warrior or arrow. Weather or not its a significant amount is beyond me. Its just a habit I carried over from my ppl training. Im working on waiting until the after landing check to do this however. Honestly though, I dont see what the big deal is. Especially with manual flaps. Its pretty dang hard to mis that lever and you can retract them without even looking.
 
I know a guy who retracted the gear on a Bonanza instead of the flaps just as the aircraft was touching down.... six months and a new belly later, the airplane is flying again.... he's not.

Don't touch nutin' until you can actually pay attention to what your manipulating.
 
SkyWChris said:
I know a guy who retracted the gear on a Bonanza instead of the flaps just as the aircraft was touching down.... six months and a new belly later, the airplane is flying again.... he's not.

Don't touch nutin' until you can actually pay attention to what your manipulating.
Click to expand...
HAHAHA! Well my CFI tells me to retract them just before turning onto the taxiway, at a safe and controlable speed.
 
SkyWChris said:
Don't touch nutin' until you can actually pay attention to what your manipulating.
Click to expand...

I can second that. My post shows an example of that. Even if there is that little button on the mixture, in the "reach and grab mode" you get into once you start to feel confortable, it can be very easy to confuse to similar things. Especially, if you only use half your attention to do that thing...and I am sure most pilots do. I am sure when most start pulling back power, they may not fully think about it. It is just kind of nature.
 
All good replies. I can see the benefit from both sides. As far as the complex aircraft go, I totally agree with not retracting flaps, fly the plane first!!

I did have a situation however that required the retraction of flaps, where if the approach was done properly it would not have been necessary. First when doing short fields you don't have much runway left so landing on speed is the best way to help in stopping sooner. In this particular situation we floated because we were NOT on speed. We bounced once (about 10'), and I grabbed the flap lever and retracted the flaps. This dropped us down back onto the runway (firmly, but not too hard), but it also KEPT us down allowing us to brake and stop. I believe if these flaps were extended, the aircraft would've wanted to still fly, and we were running out of runway quick. (A go-around was not an option because of the surrounding obstacles) This made me reconsider the lifting effectiveness of the flaps.

The previous post about the different notch of flaps and the correlating lift/drag increase was right on. (From an article in an aviation magazine, I remember reading that most aircraft have the highest increase of lift vs. drag at about 10-17 degrees of flaps). I think my concern in this matter is in possible gusty conditions, or when the airspeed is too fast when trying to touchdown. The latter should result in a go-around (if possible), but the windy condition might constitute a retraction of flaps to help us utilize the most effective braking source we have on the airplane........the brakes.

My consensus is still to shy away from retraction in complex aircraft (or any RG aircraft) on the rollout, but I believe getting more weight on the aircraft's wheels can have a big impact on stopping distance.

-ColM
 
I know if I selected 'flaps up' during right after landing to increase brake effectiveness with a Fed on the jumpseat, he'd freak.
 
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