Flap retraction on landing

Jimmy cooper said:
Because they do not have propellers to blow crap all over the flaps and possibly damage them. Plus I've been on airliners that do retract them as they taxi in. Possibly habit. To mistake the gear control from the flap control in most aircraft is pretty hard unless your mentally challenged or very new to the airplane type. Pretty absurd subject.
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It's not so much grabbing the wrong handle than breaking concentration right at a critical phase of flight. If the conditions are benign, not a big issue, but then the immediate up on the flaps doesn't do anything for you anyway. If the conditions are challenging, that look away when your plane is most vulnerable may be what allows you to get knocked out of parameters.

It's no big deal to me really, it just doesn't make sense to do in 99.9% of the time, and the other .1% of the time, it won't make that big of a difference.
 
Jimmy cooper said:
To mistake the gear control from the flap control in most aircraft is pretty hard unless your mentally challenged or very new to the airplane type.
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Yet it happens repeatedly.

Probably most often by pilots who think that to mistake the gear control from the flap control in most aircraft is pretty hard unless your (sic) mentally challenged or very new to the airplane type.
 
I tried putting the flaps up on the 150 yesterday just after touching down. I chose to do it on a 5000 x 100ft runway, full stop landing, with 5kt winds straight down the runway. So not much to go wrong.

Over the threshold at 52kias, 30 degree flaps. Planted it nicely on the mains. I love holding wheelies until it settles down on it's own. So I immediately raised the flaps while rolling on the mains, nosewheel still up. I would guess 40-45kts.

I felt it settle down more, as if more weight was on the mains. But at the same time, I felt less drag and reduction in deceleration. This makes sense. Less lift, but also less drag without those barn doors hanging down.

My conclusion: This is a light GA aircraft, not a 747. Putting more weight on the wheels to increase braking effectiveness seems irrelevant. I don't see it actually accomplishing anything. It doesn't weigh much to begin with. So I feel like reducing lift will not increase my ability to slow down. But, losing the drag will definitely reduce my ability to slow down.

I can see it being helpful in a crosswind (or tailwind) scenario. But nothing else.
 
Jimmy cooper said:
Because they do not have propellers to blow crap all over the flaps and possibly damage them.
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There are still prop airliners around.

Dash-8, ATR-42, EMB 120, etc.

And the earlier comment that airliners don't have short runways is wildly wrong. "Short" for a 737 is quite a lot longer than "short" for a 172. Burbank and Midway have both had overrun accidents with purple 737s due to the "short" runways. Neither is the slightest problem for a 172.
 
Unless I am doing short field soft field work I retract the flaps after clear of the runway and free to clean up the rest of the airplane.
 
MAKG1 said:
Huh?

You land using airspeed, not ground speed. It makes no difference to the aircraft handling whether it's calm or blowing at 20 knots. It does make a difference in the length of the ground roll.

Unless the wind exceeds the stall speed, you'll just touch down slower in the wind.

The one exception is half the gust factor. NOT the total wind. If you did that, you'd be landing on your nose gear in significant wind every time.
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When you are on the ground, ground speed and airspeed are the same thing. Roll a light sport aircraft down the runway at 20 kts into a 20 kts wind and the plane will come off the ground with full flaps deployed. In a 40 kt wind I can lift off with almost zero takeoff roll. In fact I need full power to keep from being pushed backwards. Directional stability does become something of an issue, but with enough practice it's manageable. Just make sure you have plenty of altitude before you attempt the first turn.
 
Shepherd said:
When you are on the ground, ground speed and airspeed are the same thing.
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No, they're clearly not.

Shepherd said:
In a 40 kt wind I can lift off with almost zero takeoff roll.
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Only because your airspeed and groundspeed are NOT the same thing.

I'm thinking you misspoke, right?
 
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FastEddieB said:
No, they're clearly not.



Only because your airspeed and groundspeed are NOT the same thing.

I'm thinking you misspoke, right?
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In my example, the air is moving over the wing at 40 kts. I was doing this very thing yesterday.
 
If there is 20kts over the deck, right down the pipe, you're kidding yourself if you don't think taking the flaps out won't help, especially in smaller and higher lift planes.
 
Shepherd said:
When you are on the ground, ground speed and airspeed are the same thing. Roll a light sport aircraft down the runway at 20 kts into a 20 kts wind and the plane will come off the ground with full flaps deployed. In a 40 kt wind I can lift off with almost zero takeoff roll. In fact I need full power to keep from being pushed backwards. Directional stability does become something of an issue, but with enough practice it's manageable. Just make sure you have plenty of altitude before you attempt the first turn.
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When you're on the ground with the parking brake pulled in a 20 knot wind, your airspeed is 20 knots. Your ground speed is obviously zero.
 
jordane93 said:
I think the main issue is not people mistaking the flap lever for the gear lever. It's added distraction that is mostly unecessary. That added distraction while fiddling with the flaps can cause you not to focus on other things like maintaining centerline, getting off of the runway when advised, etc.
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It's only a distraction if you're not familiar with the location of the flap handle/switch.
 
Shepherd said:
In my example, the air is moving over the wing at 40 kts. I was doing this very thing yesterday.
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Of course.

I think we're talking past each other.

In your example, the air flowing over the wing, and into the pitot tube, is moving at 40kts. Hence, your airspeed is 40k.

While, as MAKG1 points out, your groundspeed is about zero.

So clearly, in thus case airspeed does NOT equal groundspeed.

It's so obvious, I can't help but think it's a communication problem.
 
peerlesscowboy said:
It's only a distraction if you're not familiar with the location of the flap handle/switch.
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In another thread, we were discussing screw ups.

I mentioned my concept of "Mature Onset Dyslexia". I was referring to mixing up relative positions such as east and west, and several people chimed in it was pretty common.

Now, how many here have...

Turned a knob the wrong way?

Punched the wrong button entirely?

Pushed or pulled the wrong engine control?

Transposed a transponder code or frequency?

Forgotten to flip/flop frequencies?

Haven't we all done those things, the vast majority of times to no particular ill effect? When not tired or under stress?

Anyway, I KNOW for a fact I'm capable of really silly mistakes. Pulling the gear up inadvertently is not one I've managed yet, but I only have about 165 hours of complex time. For me, the best way to avoid problems is to try to do nothing right after landing, other than get clear of the runway.

Others get real busy on landing rollout - flaps and fuel pumps and transponders and cowl flaps and Lord knows what else - and most will finish their flying careers without mishap - good for them!

But we'll get to read about others, on a fairly regular basis!
 
FastEddieB said:
Yet it happens repeatedly.

Probably most often by pilots who think that to mistake the gear control from the flap control in most aircraft is pretty hard unless your (sic) mentally challenged or very new to the airplane type.
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Yet I've never heard of it happening in 45 years of hanging around airports and flying same amount of time. Never.
 
James331 said:
If there is 20kts over the deck, right down the pipe, you're kidding yourself if you don't think taking the flaps out won't help, especially in smaller and higher lift planes.
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If the wind is blowing 20 straight down the pipe and I land at 40, runway length will be completely non critical.
 
Henning said:
If the wind is blowing 20 straight down the pipe and I land at 40, runway length will be completely non critical.
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I'm not talking runway length, I'm talking about keeping the thing as "not flying" as possible once it's wheels down.
 
James331 said:
I'm not talking runway length, I'm talking about keeping the thing as "not flying" as possible once it's wheels down.
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Why?:dunno: I just keep flying it. I'm in no hurry to stand on the brakes. If I have to land that short, I'm in trouble and normal rules go away and I'll use whatever. If I have room in front of me I'm better off flying through a stable landing rather than trying to get all the weight on the wheels as soon as possible.
 
Henning said:
Why?:dunno: I just keep flying it. I'm in no hurry to stand on the brakes. If I have to land that short, I'm in trouble and normal rules go away and I'll use whatever. If I have room in front of me I'm better off flying through a stable landing rather than trying to get all the weight on the wheels as soon as possible.
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At a certain point I'm done with the flying part and ready for the ground part to begin. Nothing to do with ground roll in this instance.
 
James331 said:
At a certain point I'm done with the flying part and ready for the ground part to begin. Nothing to do with ground roll in this instance.
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We're talking a one second difference, but as you want, no biggie.
 
Everyone has their own way of doing things, which is fine.... Unless you hit my hangar ;)

I'll give ya one instance, about a week ago I was landing at a local field, ex military, runway for days.

It was 20 gusting something nasty on a healthy cross wind, but a nice day otherwise. I touch down, nice and slow with full flaps, droop ailerons, etc. even though I touched down plenty slow, still rolling with power out, I can feel that cross wind trying to lift my left wing and that's with cross wind correction inputs in, I reach down zero my flaps and that little dance was DONE, plane was steady.

Could I have managed with my flaps in, probably, was it a lot easier dumping them when I touched down, yep.

To each their own.
 
Jimmy cooper said:
Yet I've never heard of it happening in 45 years of hanging around airports and flying same amount of time. Never.
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I must admit I don't know of any first hand.

I have no idea how common, or how rare, they really are.

I know when I learned to fly it was put forth as a fairly common occurrence , but I have no idea what that was based on.

Anyway, I found one pretty quickly:

http://www.ntsb.gov/aviationquery/brief.aspx?ev_id=20001212X17579

If anyone has an idea of the real rate of accidental gear retractions, I'd be curious.

Obviously not an issue with fixed gear, and regardless, everyone will just keep doing what works for them.
 
FastEddieB said:
Of course.

I think we're talking past each other.

In your example, the air flowing over the wing, and into the pitot tube, is moving at 40kts. Hence, your airspeed is 40k.

While, as MAKG1 points out, your groundspeed is about zero.

So clearly, in thus case airspeed does NOT equal groundspeed.

It's so obvious, I can't help but think it's a communication problem.
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You're right I meant to say "In a no wind situation, while on the ground, ground speed and airspeed are the same thing" unfortunately auto correct corrected the entire first half of the sentence and I didn't catch it.
 
Fearless Tower said:
Exactly. They are unfortunately waaaay too common in pre-85 Beech airplanes.
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In the first Bonanza every switch looked identical, even the ashtray looked the same as the switches.

ibe35-03.jpg
 
James331 said:
If there is 20kts over the deck, right down the pipe, you're kidding yourself if you don't think taking the flaps out won't help, especially in smaller and higher lift planes.
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Why? You still land at the same airspeed. The only thing 20kts of wind will do is significantly shorten your ground roll, to the point where you'd probably be stopped before you could raise the flaps anyway.
 
Henning said:
The nifty thing in that pic, that's an IFR panel.:eek:
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Needle, Ball and Airspeed! That's all you really need. All these AI's, DGs etc. are just toys and more things to fail.

:D

John
 
Silvaire said:
Why? You still land at the same airspeed. The only thing 20kts of wind will do is significantly shorten your ground roll, to the point where you'd probably be stopped before you could raise the flaps anyway.
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Dude, S L O W L Y re-read what I wrote in that comment that you quoted PART of.

In that instance it wasn't about ground roll it was about ground stability and controllability.
 
James331 said:
Dude, S L O W L Y re-read what I wrote in that comment that you quoted PART of.

In that instance it wasn't about ground roll it was about ground stability and controllability.
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I read it but it all boils down to airspeed. If the plane stalls at 43 knots it's done flying at that point. The 20 knots of wind just means there is 20 knots less ground speed when it happens, that's all. There isn't an extra 20 knots of airspeed.
 
Silvaire said:
I read it but it all boils down to airspeed. If the plane stalls at 43 knots it's done flying at that point. The 20 knots of wind just means there is 20 knots less ground speed when it happens, that's all. There isn't an extra 20 knots of airspeed.
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Have you ever rolled out down a runway after landing, or even taxied a high profile, high lift aircraft in 20 gusting, say 35, knot winds?

Taking away as much lift and weather veining as possible helps.
 
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