Lowering Flaps in a turn?

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victory_aviation
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Lowering Flaps in a turn?

Post by victory_aviation »

I have been taught 2 different things during my private and commercial training. I just want to see what others think.

Should you lower flaps in a turn? Or wait until wings are level? Why?
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sky's the limit
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Post by sky's the limit »

There is ABSOLUTELY nothing wrong with lowering flaps in a turn, just be aware of the effects.

stl
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Ralliart
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Post by Ralliart »

I agree with stl.
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Sulako
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Post by Sulako »

I also agree.
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just curious
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Post by just curious »

For what it is worth, we don't apply flaps in the DeHavilland world during turnes due to a series of flap actuator rod failures in the 70's. Application during the turn meant a failure could develop without time to counteract it.

DMR of rainbow air met this particular fate
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Post by . ._ »

I don't but I catch myself doing it from time to time. "Oh shit! I forgot flaps!"

I was taught by a few instructors not to do this because if one goes down and the other doesn't, you're gonna roll, baby roll!

Just for kicks, I'd like to get in a plane with only one working flap to see if the roll could be counteracted by aileron. Or just play with it to see what happens- straight and level, turns, stalls etc.

Uh oh, I'm starting to sound like Cat Driver with my "pushing the envelope training at safe altitudes" attitude.

-istp :smt087
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sky's the limit
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Post by sky's the limit »

istp wrote:
I was taught by a few instructors not to do this because if one goes down and the other doesn't, you're gonna roll, baby roll!
Ok,

This is an old wives tale. If you are flying around worried about this, may I respectfully suggest you don't turn the key in the first place?(not istp specifically :wink: ) I have had a flap come out of it's tracks and partially deploy, it's not a big drama.

If there are airworthiness issues as JC addressed, then don't. Design flaws aside, flaps away.

atl
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bcflyer
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Post by bcflyer »

I've done it for years in King Air's, MU-2's, Caravan's, Dash-8's, Fokker-100's, and RJ's. I don't see a problem with it.
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happily.retired
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Post by happily.retired »

Even if the risk of unequal deployment is minimal, shouldn't a pilot minimize any risks s/he can. If you NEED to lower them mid-turn to safely land then fine, the risks are pretty minimal, but there is rarely any need to, so why bother unnecessarily upping your risks even a little bit?

On a side note, I think it was on my commercial ride, the examiner asked me if this was possible in the 172. I said it could theoretically happen if the connecting mechanism failed and he agreed with me (for what it's worth)
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Trevor
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Post by Trevor »

istp wrote: Just for kicks, I'd like to get in a plane with only one working flap to see if the roll could be counteracted by aileron. Or just play with it to see what happens- straight and level, turns, stalls etc.

-istp :smt087
Back in the 70s my father was delivering a Cessan 310 to its owner. Having been some time since he'd flown a 310, he practiced some circuits at altitude. During one, just as he was coming over the imaginary fence, he dropped full flap and things went to hell. The flap cable broke and only one deployed - right to 40 degrees.

It took him more than 2000 feet to recover from the roll and spin.

Now imagine he was on short final and about 150-200 feet altitude when he dropped the full flap. You wouldn't even know what happened.

To this day my dad claims he heard a voice tell him to do one more circuit. Which guardian angel it was, he's not sure, but that's all he credits with getting out of that one.
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Post by Wasn't Me »

Lowering flaps in a turn is fine as long as you are prepared for the famous flap failure. One flap stops working while the other keeps going. The PA31 is famous for this and has the flaps restricted to 25 in some of the models. Others had a fix done to the flap system to help prevent this. It is still mentioned in the POH.

In the past a few C172s have had flap failures where the chain runing the second flap failed. It's not a wives tales but a real problem that is going to happen more and more as the fleet gets old.

Do what you want, your the PIC, just be prepared to fly the airplane when you have to.

I have had a flap fail on one of the aircraft I fly. It flew fine with aileron and ruder until we landed. The flap was only exted about 20 degrees.

I put flaps on in a turn when I have to. Some of my approaces into CYYZ there isn't much of a final but a big half circle from Bramalea. Do what you got to just be aware.
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Post by Hedley »

If the infamous asymmetric flap deployment occurs, can you immediately raise the flaps to equalize them again? Or does the one deployed flap always remain in the extended position on all aircraft types, regardless of inputs?

This kind of flight control weirdness can sometimes be overcome by pilot technique. There are countless instances of pilots taking off with an aircraft fresh from heavy maintenance with the controls rigged incorrectly - usually with fatal results.

However, I seem to recall at least one incident report where the ailerons were rigged BACKWARDS and the thoughtful pilot figured out what was going on, and flew a careful circuit with the reversed ailerons and safely landed.

A flight control problem is not always fatal. I have had an elevator jam up on me in a vertical downline in a Pitts. I recovered and landed uneventfully using the (pitch) trim.
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cessnafloatflyer
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Post by cessnafloatflyer »

I teach that it is fine to lower them in a turn (adding lift) but *Never retract them in a turn, to be that is bad airmanship unless your airspeed is at cruise. So in the curcuit, t/o, landing, don't retract them.
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xsbank
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Post by xsbank »

I think that this originally came about long time ago in initial training in the military where there may have been a significant pitch change with deployed flaps that required counteracting with trim - I think this lead to a few stall-spins, hence the prohibition.

Now this is much less of an issue and a failed-flap scenario will not make any difference if you are level or banked. I've had ailerons jam but not flaps, but I did see an Aerostar that had them jam on retraction and apparently the roll was nearly uncontrollable with those small ailerons and that tiny rudder. Happy ending, though.
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Post by 32a »

I was trained under the "don't move flaps in a turn" philosophy. Been flying airplanes with asymmetric flap brakes for many years. Given the available systems and potential consequences, it still appears quite important to DETECT asymmetric flap movement and do something about it early. So now, I only move flaps with stable bank and not while rolling in/out of a turn. For your consideration.
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TenForTwelve
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Post by TenForTwelve »

One thing nobody mentioned here is that most airplanes (ok, the ones I fly anyway) have something in the POH that says to operate flaps in small increments to minimize roll tendency if the flaps go assymetric. In our PA31's there is a placard in the cockpit. I sometimes operate flaps in a turn, but only a little at at time. Like everyone else has said, just be a little prepared, and be aware of what can happen.
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good_idea
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Flaps in a turn

Post by good_idea »

The only reason why it would be a problem is if the pilot lowering them in a turn was not anticipating the resulting effect of them. As long as you adjust go for it and put flaps down in a turn

good_idea
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