Flaps at full speed.

SixPapaCharlie

SixPapaCharlie

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Flying home from lunch today, cruising along at 160-170 and my 9 year old adjusts the volume on the ANR headset (hand piece) and accidentally drops it. (I am unaware)

It falls onto the flap switch and knocks it into the 1/2 flaps position.
1/2 flaps is supposed to be 119 kts or less

I was not aware as believe it or not, I was eyes out looking at a Cessna I was overtaking.

From my perspective, I am flying and suddenly the plane pitch rapidly changes and the A/P starts flashing TRIM TRIM TRIM

I am a big "Undo what you just did" thinker but I hadn't done anything to undo.

I disengage the A/P and start a flow to check what all is set and I see the flaps are at 1/2.
I look out, and they are deployed, I check my airspeed and I am 40+ kts above 1/2 flap speed.

Retract flaps and everything is normal.

In hindsight, what is the lesson here?

That switch could be hit by any passenger at any time.
I have had knees hit the mixture knob and random feet push rudder pedals but this might be more significant. That switch is set so that you adjust it and it goes. It is not a "1 potato 2 potato 3 potato" switch that you have to hold.

What say the peanut gallery on this one?
Is it a big deal? What could have happened if it went full flap at that speed?

FWIW, I would estimate 5-7 seconds between when I noticed the plane reacting, and me reducing the flaps.
 
It really depends on the aircraft. In some, you look at the flap attach points and the spar and structure and know it'd take some awful forces behind what an overspeed extension by itself would do, to cause any harm.

In others you've looked at the wimpy hardware at the attach point or know the linkage to the motor or the load structure looks awfully wimpy for such a thing.

The safe "CFI voice" in my head says you can always have a mechanic look over things and make sure nothing got overstressed, but the realist voice in my head says "probably fine" for most lightweight singles. Maybe did a small amount of additional unnecessary wear on the load bearing components.

Just hard to say without knowing more about Cirri wing structure. Sorry don't have any Cirrus time or looking at them to offer a better opinion for you.

Many times the limitation is there because the hardware doesn't like being moved with higher aerodynamic forces but it can handle the stress. Other times it's based upon the stress on the structure overall as a unit.

Still other times it has nothing to do with either (like on landing gear systems) and is simply a limitation of the power available to the motor or hydraulic pump, working against a load, more than it being an airframe or control surface mechanical issue.

Best advice: Ask mechanic. Also maybe in one of the newer large style AFMs or POHs there's some more detail about what the limitation is driven by. (Almost never in the old pamphlet style POHs of yesteryear...)
 
Worth having your mechanic take a gander at it.
 
Pull the books and see what they say about an overspeed. We just had to do one on a company a/c when the pilot accelerated a little quick and blew past an open door speed. Fortunately, for ours, it was a simple inspection of couple of items and an ops check. I've had others that require extensive inspections.
 
Flag it on your squawk sheet and have your mechanic take a look. Better to recognize it now, than progress into something larger later.
 
You guys have squawk sheets for your personal planes??

I just call my mechanic up and we both turn wrenches.
 
Seeing your airplane is now a dangerous collection of unusable parts, you will have to sell it to me. I will give you an excellent salvage value price.
 
Hank S said:
I don't understand--flying a Cirrus too fast (apparently above Vne, or with flaps down above flap speed) can damage the tires???
Click to expand...

Sure. After all the control surfaces break apart, the tires are one of the first items to impact terrain during the crash. I suppose you can save the tires by crashing upside down, if that's an option.
 
That's what happens when you have those fancy-scmancy headsets. Your whole plane coulda come from together!
 
Chances are if you were straight and level, but too fast, for <30 seconds you didn't hurt anything. You didn't mention the sky conditions, but I assume clear and smooth since you would have already slowed down if there was any chop.

Have it looked at, but probably nothing to be found.
 
I'd also suggest, in the event of future occurrences, that you slow to the appropriate flap speed before retracting them to prevent potentially higher-then-normal wear.

As always, YMMV.
 
Hank S said:
I don't understand--flying a Cirrus too fast (apparently above Vne, or with flaps down above flap speed) can damage the tires???
Click to expand...
Hank: That reference is most like in the case of a touchdown at speeds well in excess of normal landing speed, or holding it on the runway until way past normal flying speed. We have the same requirement if a pilot lands way above normal speed, as the touchdown forces can cause the tire bead to slip on the wheel. With 32 ply tires, slipping a bead means a tire change and tear down and wheel inspection.
 
I thought we all learned flaps were not supposed to be used, ever.

See a mechanic, have them welded up, so the kid can't do that again.


Sent from my iPhone using Tapatalk
 
Thankfully you were not in an RV-10...95 kias max at 1/2 flaps or 15 deg. You would not have time to troubleshoot before pieces rained down over Texas.
 
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