Student Pilot wrote:maybe I'll try it tommorrow?

Like most everything else, the technique is just a little tool to have in the bag of tricks.

The seat of my pants tells me what works and doesn't work... For me. And for each specific airplane I fly because they're all different. Nothing scientific or great aerodynamic theory behind it, because that's too complicated for my poor old brain to compute. It just feels like it works when it's happening. For me.

In my prior life I spent all day, every day, going in and out of muddy, icy, snowy narrow and short gravel strips, with strong crosswinds. When landing I wanted to change from flying machine to road vehicle as soon as possible, and dumping the flaps seemed to stop the flying instantly (as long as I wasn't sloppy with my airspeed). It's that transition period where most of the bad stuff happens, and anything I could do to minimize that time made me, and my airplane, feel better.

Now... Do I do it each and every landing on a calm day just bouncing around for fun? No. But, I know exactly where the flap handle is at all times without having to look at it, and it's hard-wired into my reflexes to grab it, push the button on the end and slam it down until I hear that big loud bang if/when something bad feels like it's trying to happen!!!

Gump

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?

They don't need to because with the spoilers there isn't much lift left.
If you think your aren't producing much lift at your full stall landing, your wrong. If you weren't producing most of the aircraft's weight in lift, you would hit hard, real hard.
The biggest reason in "dumping" flaps to get in short is to increase brake effectiveness on non paved surfaces. It's not going to make much difference on pavement. It also moves the center of lift back farther on the wing, and will help hold the tail down. Try this, wheel land with one notch of flaps and on roll out with the tail still in the air retract the flaps and tell me what happens to the tail.
I agree with MTV on the Cessna flaps as far as retracting them as well. Ever come across the threshold on a hot day and get into "float" when you get over the hot pavement? Well on a 210 if you reach over and pull the flap handle up, she will settle through that "float" and land as pretty as you please. I assume other Cessna's will do the same.

a64pilot wrote: The biggest reason in "dumping" flaps to get in short is to increase brake effectiveness on non paved surfaces. It's not going to make much difference on pavement

It helps on pavement too. You can get "light" on the wheels on any surface and not have good braking for a whole lotta reasons.

And it's not just for braking that the technique comes in handy. A bit of a bounce that can be avoided, a gusty wind trying to push a wing, lots of stuff... When it's crappy I know I'd rather ride it out on the ground driving with my wheels controlling where I go and the wing not contributing to any part of the deal, than be kissing the dirt with my tires, counting on only a rudder and my big clumsy feet to keep me lined up.

Gump

I generally do use the dump the flaps tecnique when trying to get the husky in short or in gusty situations. But there is also another reason for doing it that differs from many other airplanes. When you add flaps in a super cub it tends to pitch upwards, in the husky the nose pitches downwards, which is gread on approach because it helps keep you in trim. The problem comes just about at flare with the power off and just me in the airplane there is not enough elevator authority to put the tailweel on the ground even with the stick in your gut. there are two solutions to this proplem: Come in with power behind the power curve which I have done before but save for thoes places that are truly short, or dump the flaps when the mains touch and the tailwheel comes right on down and allows me to use more brakes. Without lowering the flaps and atempting to make a three point landing i roll down the runway quite a ways witht the tail low but not touching before I can bleed off enough speed to bring it down.

All this dump talk reminds me that I need to go to the bathroom.

Savannah-Tom wrote:All this dump talk reminds me that I need to go to the bathroom.

Best of luck.

Of course instead of dumping flaps, you could just crack it into beta just before the mains come down and then into full reverse as the tailwheel is planted

Well I am a flap dumper too but I will add a new reason in the mix. I use the technique for all the reason stated before but with my Stinson I land with full flaps and take off with two notches. So if I should need to do a go round I can climb better and with more control after dumping flaps to at least the second notch. Therefore in a tight spot I will touch down, dump flaps to the first notch and stand on the brakes. If something goes sideways on me I can hit the throttle and reach the flap handle real quick. A tug to second notch and hand back to the throttle, up, up and away.

Shorten,

How do you do that? Stinsons only have two notches of flaps? Unless you have a "field" modification.

On the later Maule flaps, you can retract from 48deg down to -7deg up in one very fast smooth movement. This allows you to correct an overshoot, or a gust etc and plant the mains within a foot or two of where you want.
Now the good part is that the negative flap not only eliminates any possibility of inadvertant lift, but causes drag above the wing and any residual airflow holds the tail down allowing a brakes on landing without noseover. Max shortfield.

Tried it, doesn't seem to make a lot of difference. Was landing with a 15 knot quarting tailwind and the Aircraft was on the ground anyway. Tried it for the first half dozen or so landings, just seems to complicate things.

In the game I'm in the least you can do the better so I just roll to the end of the strip turn round and while the loads going in I retrim, put the flaps up, have a bit of a look at the timer and temps and blast off for another one. Good work today, did 60 loads before lunch, 40 after.

To be honest I can't remember having trouble with the Aircraft coming off the ground, that's unless I stuffed up the approach and landing. So I think I'll just stick to tongue in cheek method it works for me.

After reading some of these replies I think there is 7,943,324 different ways to land an Aircraft, think I'll just stick to the way I've been doing it the last 29 years.

GumpAir wrote When landing I wanted to change from flying machine to road vehicle as soon as possible,

Great way of putting it...

When I earnt a living flying 180/185s it was the norm to retract the flaps and I still do it on my 180...in fact the Cessna handbook recommends it.

Along these lines, a friend of mine in NZ recently bought a 180 off an old ag-pilot who probably had 10-15,000 hours on the type [the 180/185 was a very popular ag plane in NZ from the mid 50s to the 70s].

Although my friend has lots of 185 time he got the guy to check him out and it was demonstrated a method of getting a very short landing...basically approach as slow as possible and where you get to where you want to touch down, retract the flaps at the same time giving the elevators a bit of a tug...

Tried it myself back at the strip the other day...it works, a smooth but positive touch down and a very, very short ground roll...

Student Pilot,
What are you flying and what are you doing getting in a 100 loads a day? That combined with landing with a tail wind gives me a clue.
Depending on what type of aircraft and what you are doing, dumping flaps may not be of much help at all. For example if your landing light and leaving heavy, why bother? Your going to need lots more room to get out than in.

a64pilot wrote:Of course instead of dumping flaps, you could just crack it into beta just before the mains come down and then into full reverse as the tailwheel is planted

Try that on wet ice (or any really slippery runway surface) and you'll go for the ride of your life!!!!!!

Gump

Hi Student,

I am guessing with your experience level, you already knew the obvious and were just looking for a hidden gem you might have missed.
As a floundering fledgling of a pilot I can't add a whole bunch, but it does strike me odd how many people call it a distraction? Except in the most extreme of cases I can't imagine moving one lever a distraction. And certainly not for a pilot whose job consists of coming into a field over wires, to push a lever, flick a switch, monitor a flow rate, peek at a pressure, track a course (to one foot, no easy ILS stuff here...) , over the sprinkler, under the high line, up at the end, pull the lever flick another switch...all at 100 ++ mph...you get the idea....
I also agree with the notion of , If you got a loaded spray plane off the strip, this technique is probably not going to be needed to get back in. I never use this trick in a work plane. Why? easy...I will never need it in that environment.
I do it in my cub on almost every landing. Why? easy... muscle memory... I don't have to get "distracted" when I really might need it, it's built in. And I'm a lot more likely to fly it (my cub) somewhere I might need, or appreciate it. I have declined to use it in really complicated places, but have always noticed how less "solid" the roll out felt.
As to not noticing it in your work plane, I think of it this way... Your work plane probably wouldn't care about a load of 72 gals. landing or departing,
but the pacer in your avatar sure would
Light little planes notice light little differences...
Take care, Rob

Of course instead of dumping flaps, you could just crack it into beta just before the mains come down and then into full reverse as the tailwheel is planted

I watched the Oregon Aero guys do this with their Pilatus PC12 last weekend. They did it all day long into a 2000 ft grass strip and gave more than half of it back each time. I think the only problem they had stopping that short was that it made some water slop out of the jacuzzi in back.

a64pilot wrote: Depending on what type of aircraft and what you are doing, dumping flaps may not be of much help at all. For example if your landing light and leaving heavy, why bother? Your going to need lots more room to get out than in.

Doesn't that go for most anyway? How many actually have to land at the minimum landing distance? If your landing heavy then your going to use that distance getting off anyway, why bang it on and flog your brakes?

Rob wrote: I think of it this way... Your work plane probably wouldn't care about a load of 72 gals. landing or departing,
but the pacer in your avatar sure would
Light little planes notice light little differences...
Take care, Rob

Your right the little machine does notice things, If it was an absolute crap day windwize then I might do the flap thingy on landing, otherwise the flaps usually stay down until I turn off the runway.

Student Pilot wrote:

a64pilot wrote: Depending on what type of aircraft and what you are doing, dumping flaps may not be of much help at all. For example if your landing light and leaving heavy, why bother? Your going to need lots more room to get out than in.

Doesn't that go for most anyway? How many actually have to land at the minimum landing distance? If your landing heavy then your going to use that distance getting off anyway, why bang it on and flog your brakes?

Sometimes some of us come in quite heavy and leave quite light, which means you need less runway to T/O than to land, Then there's the one way strip that has you landing with a tail wind, but departing with a head wind. And of course there is just the wet grass, slick surface that means you need as much weight as you can get on the wheels in order to get the brakes to do anything at all
I've got a couple of hours in an AG plane and of course those airplanes are flown by professional pilots and are flown with far less performance per pound than anything else I've ever flown, it's a different animal. Also remember that a GA airplane has to stall at less than 61 kts at max gross weight. Most of what we here fly are much less than that, but an AG plane only has to stall at 61 kts. with an empty hopper.

Sorry about the delay in responding, I was out of town.

Yes my Stinson has three notches of flaps, It came that way to me. I know the origional configuration is just two. The third notch is really handy though, it is just 5 degrees or so but really helps during climb out and like I said it makes the handle a whole lot easier to get hold of.