sssshhh, don't tell, mine does as well. The fist notch is set so the flap extension is the same as a full aileron deflection, works very well . The flaps are uhh not the best, not bad but could be better .

Student Pilot wrote:

a64pilot wrote:Why do the big airliners have spoilers that deploy on touchdown?

Why don't big Airliners pull their flaps up after touching down?

Two thoughts come to mind. First, changing configuration at a critical phase of flight is something I'm sure the FAA frowns upon. Also, I'm sure that the "wrong lever" issue plays a role here as well. Second, from a aerodynamic standpoint, airliners have lift dumpers/spoilers that deploy at or shortly after touchdown (usually based on weight-on-wheels sensors, wheel spin-up, and sometimes a time delay). Once those devices kill the lift, the flaps essentially become underwind aerodynamic breaking mechanisms. With all this happening on 121 aircraft that doesn't happen on most GA aircraft, it becomes an apples to oranges comparison.

I use flap dumping on my 172/182. Usually it is with the 182 in backcountry trips, with my wife being the flap retractor. It's a great way to minimize the distraction factor and to include your spouse as a crewmember of sorts (CRM). "Flaps up" is what she hears and there are times when I can feel the aircraft's weight shifting to the mains and the brakes becoming more effective.

I think Sparky talks about this. Those of you that within easy access to his book, what does he say?

There still hasn't been anything hard on getting rid of flaps after touching down, it's all "I recon", "Jimmy's big brother said" or "Trust me, I know better" stuff.

I'm sure that the aerodynamic braking of the flaps (especially just after touching down) would make up for the supposed more efficient wheel braking. What about on wet or slippery surfaces? Are there many operations where you ONLY land heavy and take off light?

Seems to me the only legitimate use would be with REALLY shitty windy conditions landing with some headwind component then killing a percentage of the lift (By "Dumping" flaps) to stop balloning if you touch down too fast.

There still hasn't been anything hard on NOT getting rid of flaps after touching down, it's all "I recon", "Jimmy's big brother said" or "Trust me, I know better" stuff.

Student Pilot wrote:Seems to me the only legitimate use would be with REALLY shitty windy conditions landing with some headwind component then killing a percentage of the lift (By "Dumping" flaps) to stop balloning if you touch down too fast.

From my own experience in lots of "really shitty windy conditions" touching down "too fast" wasn't really the issue. In the small Cessnas, working with sustained winds at 40-50+ KTS the wing is producing lift at even a slow taxi (or stopped) and keeping lined up on a narrow, slippery strip took about all the skill a guy had. Dumping flaps killed a percentage of that lift and made the airplane a wee bit easier to control. And if while touching down things felt a bit out of the comfort zone, dumping flaps NOW meant more control NOW.

Gump

a64pilot wrote:There still hasn't been anything hard on NOT getting rid of flaps after touching down, it's all "I recon", "Jimmy's big brother said" or "Trust me, I know better" stuff.

So could somebody post some factory handling notes, manufacturers recomendations, training manuals or anything apart from hearsay?

GumpAir wrote:From my own experience in lots of "really shitty windy conditions" touching down "too fast" wasn't really the issue. In the small Cessnas, working with sustained winds at 40-50+ KTS the wing is producing lift at even a slow taxi (or stopped) and keeping lined up on a narrow, slippery strip took about all the skill a guy had.
Gump

Your a better man than me Gunga Din, 50+Kts

Student Pilot wrote:Your a better man than me Gunga Din, 50+Kts

On the Arctic Coast of Alaska the wind blows like that for days at a time, and the direction is so true you can set your compass to it. As long as there was visibility, we flew in those winds day in, day out. My steed for most of my years up there was the Mighty Cessna 207, Sled is it's nickname, as it's pretty much the direct replacement for the dog sled, and that airplane was/is absolutely amazing in how much wind and weather it can handle.

Gump

I'm on the road right now but as soon as I get home I'll dig to see what Sparky has to say about it. I'm pretty sure he mentions it in his Mountain Flying Bible. As far as a source, for the type of flying that this website is dedicated to, you can't get a more definitive source than Sparky.

It will be a few days before I'm home so anyone that can beat me to it, by all means go for it.

Student Pilot wrote:

a64pilot wrote:There still hasn't been anything hard on NOT getting rid of flaps after touching down, it's all "I recon", "Jimmy's big brother said" or "Trust me, I know better" stuff.

So could somebody post some factory handling notes, manufacturers recomendations, training manuals or anything apart from hearsay?

Ok, here are some references for you.

1- First is an article from AOPA flight training on PTS standards for performing short-field landings during a check ride. Here is an excerpt and the link for the full article.

"An airplane's POH/AFM may recommend flap retraction after landing to increase the brakes' effectiveness. This recommendation requires a ticklish division of the pilot's attention. Many examiners subdivide a short-field landing into three segments -- closing the throttle, raising the flaps after touchdown, and applying the brakes. These actions happen so rapidly it's unlikely an examiner can observe them individually. Instead, the examiner judges your prompt, safe dissipation of kinetic energy.

If flap retraction is part of the recommended short-field after-touchdown procedure for the airplane you fly, the examiner may take the opportunity to test your knowledge with a question such as "Why do you raise the flaps after touchdown?"

The examiner is probing your understanding of the concept that full flaps produce lift along with drag. During a short-field rollout, you want the maximum amount of weight on the wheels to increase the effectiveness of the brakes. Retracting the flaps decreases lift, which increases the weight on the wheels. Your answers to these and other questions, coupled with your handling of the airplane, demonstrate to the examiner that you understand and can perform short-field approaches and landings. Congratulations -- another checkride task successfully completed."

http://flighttraining.aopa.org/members/ ... s/1338.cfm

2- This article reminded me of what the POH states for 172s/182s. The following is taken from a 1980 C182Q POH, page 4-20.

"Short Field Landing

For a short field landing, make a power-off approach at 60 KIAS with 40 degrees flaps and land on the main wheels first. Immediately after touchdown, lower the nose wheel to the ground and apply heavy braking as required. For maximum brake effectiveness, after all three wheels are on the ground, retract the flaps, hold full nose up elevator, and apply maximum possible brake pressure without sliding the tires."

So, there you have it from sources other than hearsay. For those of you flying Maules, Cubs, 185s, etc, how about digging in your POHs and share what you find.[/img]

Thanks for that it's fairly comprehensive, I just read a 185 manual and it say's the same thing. Another bonus would be on very gravelly strips it would reduce flap damage from stuff thrown up from the wheels.

I only do one tarmac landing in every 50 or 60 landings, the rest are on shorter (500 metres or less) grass strips and in the last 130,000 or so landings have never felt the need to pull the flaps up after touching down.

OK so there are times when it could be useful but to me efficiency is the winner, the less you do the better. If I keep practicing I might get it right one of these days.

Grassstrip,

You beat me to the punch last night as I was reading the same texts for Student. I have Cessna manuals for the 1980 c150, 172N, 172R, 172S, 182S,
and it's all the same. Chapter 4 is the chapter for normal procedures in all Cessna books. A quick look shows this procedure to be the case for all short field (not standard) landings.

This is what "Jimmys big brother, the FAA rekons", maybe we should "trust him, since he knows better":lol:

FAA-H-8083-3 the FAA / USDOT book "Airplane Fling Handbook" Ch14 pg15 under Short field landing:
Short field landing procedures are similar to in a normal approach and landing. Approach with full flaps at the recommended short field approach speed. If a recommended speed is not furnished, after landing is assured and the wing flaps are extended, a rule of thumb is 1.2 Vso, but not less than Vmc for safety. Immediately after touchdown, raise the flaps, apply the back-elevator pressure and apply brakes.

A source more widely accepted by back country type (F.E. Potts) says this:

Ch19, Pg 138, Pp " Use of flaps - high wind conditions "
....Then coming over the threshold with full flaps, he reaches down and releases the flap lever so that flaps go to 0*. This is done just at flare, and when the timing is right the airplane drops on to the ground nicely in the three point attitude, then if the strip is smooth, hard, and long enough, the pilot brings his airplane up to the three point position and applies his brakes.

later in the same chapter, under the paragraph "tricycle gear (c206)"

.... 3) Needless to say, flaps should be retracted right at touchdown.

and the chapter ends with this:

( It should be noted that a lot of instructors take a very strict position on retracting the flaps during the landing roll: you are not to do it under any circumstances. The reason for this is that a lot of pilots have managed to retract the gear accidentally while thinking they are retracting the flaps. And I will admit for those of you that will be going from 152s to light twins, to commuters, to the airlines, this may be a reasonable position to take. For those pilots will rarely have an opportunity to operate from seriously marginal strips.
However bush flying is a very different game and it uses mostly fixed gear airplanes, so this quite sensible rule has to be disregarded if you are to operate under those conditions.)

Looking at Sparky Imeson' " Mountain Flying Bible"

There are so many references to this maneuver, that I would basically be re-writing the book to illustrate them all. Apparently, my "big brother" Sparky approves
. I will point out this however, Sparky is the only one who uses your words of "Dumping the flaps" verbatim. And he does so as he describes a botched approach arriving at the threshold floating. Whereby he suggests a forward slip, Dumping the flaps or a combination of both. See page 5-47 Ch "SHORT-FIELD PRECAUTIONS
I have been at this situation a few times.... It can be a handful (for me) but when the choice is get down and on the brakes, or use the trees at the end for brakes, it is a no-brainer...

Student Pilot,

I really have to thank you for bringing up this thread. I currently have good blocks of "spare time" I study a lot during these times, but this thread gave me the opportunity to go back and revisit a few good books like "stick and rudder", Sparkys, and Potts'

Take care, Rob

Hey Rob,

Like I said, I have way to much time on my hands right now in front of a computer. But I will echo your thoughts. This has been a good thread and a great review. I had forgotten about reading about the trick to dump the flaps just prior to the flare for us electric motor users. I'm anxious to go out and give this a try. I floated a landing last week that I really didn't want to and this technique might have come in handy.

Thanks for posting some good references.

Guess I've always been a flap dumper. Didnt know there was any other way.

I was just re-reading FE Potts last night, getting excited for winter, and he states that ski landings can be a good time to ADD full flaps on landing. Since there is no other means of braking, the theory is that this added drag can help to slow you on those icy, longer-than-hoped-for run-outs. Then there is the Jay Hammond method described in "Bush Rat Governor": Jump out of your supercub and hang onto the wing strut with your heels dragging in the snow Fred-Flintstone style. Of course Hammond goes on to describe the grizzly aftermath of breaking his ankle in remote Alaska this way...

Anyway, it's interesting to think about. I suppose FE Potts' method works best if you haven't already selected full flaps on final approach. Or how about using it for wheeled landings with poor braking action?

One of the most "aha" moments I remember having with an instructor was him telling me not to abruptly make adjustments in my (manual) flap settings, but to ease between one setting and the next, to temper the airplane's reaction. I think this did a lot to smooth out my flying, especially near the ground- when it counts!

"Since there is no other means of braking, the theory is that this added drag can help to slow you on those icy, longer-than-hoped-for run-outs."

had a friend of mine go sailing that way across the lake on glare ice and into a birch tree...right in front of his wife watching from the house...wives don't forget these things

I don't know squat about ski's, there just isn't much call for them down here, but on my trip to AK about 40 years ago as a kid, I remember hearing some bush pilots talking about throwing a rope under the ski for braking action? I assume the rope would have to have been tied to the airplane for it to work and now that I fly it seems like one of the better ways to invite a ground loop, but is this an actual procedure?

a64pilot wrote:on my trip to AK about 40 years ago as a kid, I remember hearing some bush pilots talking about throwing a rope under the ski for braking action?

Wow, good memory! I guess it shows how impression-forming airplanes can be for some of us

I've never heard of this as a technique on landing (seems like it could foul the prop too easily), but it is a technique for making a tight turn when taxiing on skis. You add drag to one ski to help the other one come around. Rope could work for this. FE Potts (F. E. Potts' Guide to Bush Flying: Concepts and Techniques for the Pro) has a nice-looking, retrievable system using a rope and a length of wood, though I've never tried it.

I still fly light enough aircraft that I can horse the tail around with the BAS handles when I need to. When I've been stuck with bigger C185's, it's time to get the passengers out and have them hang on the inside strut. Nice way to get a face full of snow!

Went out and did some "flap dumps" this afternoon. No, I didn't have too many flapjacks for breakfast, I was trying out the advice of some of the old timers in this forum. All I can say is YES! It is a great technique.

With either full or half flaps, grabbing the flap control I could gently set the plane on the ground as I skimmed just over the surface. It was remarkable how much "feel" there was to the flap lever. It was sort of like using the elevator, but it was pretty much one way; touch down and you are done.

This is a neat trick for your repertoire. Thanks to you experienced guys.

tom

I left Haines on glare ice and landed Skagway in 20 K gusting winds, and I absolutely used the flap dumping. With that much wind banging around I flare, hold just off the runway and wait till I get a stable second then drop the flaps and concentrate on holding things straight. This way if I keep the tail up the plane won't fly off again in a gust.

Landing back in Haines on ice the wind was twenty degrees off line but fairly steady so again I crabbed in to just off the ground, then straighten out and dump the flaps, keep the tail up so I have good rudder and taxi on it.

Works for me!