Departing with flaps.

Challenged

Challenged

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Challenged
I had a trip planned a few days ago to fly the Bonanza to Dallas in order to have an A&P there replace my engine monitor. The field where the plane currently resides did not have fuel, so I flew ~ 10 minutes or so to another field to fill up prior to flying to Dallas.

I put the flaps down to land, but once I was off of the runway I could not retract the flaps. There was not a single person on the field to assist me, so I was sitting there wondering what to do next and I was contemplating various options, including a full flap departure. The story has a happy ending, as I spent about 20 minutes on the phone with my mechanic, and even without tools on board he was able to walk me through tweaking some micro-switches under the wing and doing a fuse reset to get things going. It did leave me wondering what I would have done had I not been able to get my flaps operating again.

Would you be comfortable with a full flap departure in a situation like this? Would you leave the gear down to help keep the airplane slow? Would you have flown a long trip in that configuration, or just fly back to your home base? Would you just leave the plane there and try to get a mechanic there to look at it at some later date?
 
Don’t try a full flap departure without practing it first. Not in a Cessna, at least. You can manage it given enough horsepower but it'll surprise you if you don’t know what to expect.
 
I'm not sure I do a full flap departure in any aircraft. 10 degrees or 20 degrees in most GA aircraft, sure. But then you're going to be flying slow as **** to stay under Vfe
 
I was in a C-207 and landed at Kobuk, AK on a Friday afternoon to deliver mail and groceries. As I exited the airstrip I put the flap handle up. Nothing.

I played with the micro switches under the dash and still nothing. I got on the phone and called one of the mechanics. Since it was a land line I could not be on the phone and in the plane at the same time, but I was able to try what he suggested. Still full flaps down and not a sign of life.

Since it was Friday afternoon and I sure did not want to stay all weekend in a little village of about 150 folks, so we got a ferry permit. I took off with full flaps and slowly came home. The plane was empty for the return trip and that was a pretty short take off run before I got airborne. The plane flew just fine, but slow.

A C-207 with full flaps and full throttle won't get near VFE, so that wasn't a problem. I have very little time in a Bonanza, so I am not sure how it would act with a full flap takeoff. I probably would have left the gear down for a short trip.
 
Where does it say they’re prohibited? You guys need to learn more about your airplanes!
 
Stewartb said:
Don’t try a full flap departure without practing it first. Not in a Cessna, at least. You can manage it given enough horsepower but it'll surprise you if you don’t know what to expect.
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I’m missing something here, isn’t practicing it first, trying it?
Or maybe you are meaning that with flaps operable, one could retract them if it started going bad? So, definitely not in that situation where the only option is abort?
 
Zeldman said:
I was in a C-207 and landed at Kobuk, AK on a Friday afternoon to deliver mail and groceries. As I exited the airstrip I put the flap handle up. Nothing.

I played with the micro switches under the dash and still nothing. I got on the phone and called one of the mechanics. Since it was a land line I could not be on the phone and in the plane at the same time, but I was able to try what he suggested. Still full flaps down and not a sign of life.

Since it was Friday afternoon and I sure did not want to stay all weekend in a little village of about 150 folks, so we got a ferry permit. I took off with full flaps and slowly came home. The plane was empty for the return trip and that was a pretty short take off run before I got airborne. The plane flew just fine, but slow.

A C-207 with full flaps and full throttle won't get near VFE, so that wasn't a problem. I have very little time in a Bonanza, so I am not sure how it would act with a full flap takeoff. I probably would have left the gear down for a short trip.
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Is there even a way to calculate fuel consumption in a trip like that? I’m guessing no.
 
If the airport is about to be overrun by zombies, I'd probably try to depart, but otherwise I would not. Especially since you're not that far from home base
 
Challenged said:
Would you be comfortable with a full flap departure in a situation like this? Would you leave the gear down to help keep the airplane slow? Would you have flown a long trip in that configuration, or just fly back to your home base? Would you just leave the plane there and try to get a mechanic there to look at it at some later date?
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No
Yes
Home
Maybe
Wouldn't do it in my Sport, it's to underpowered...:(
 
LongRoadBob said:
I’m missing something here, isn’t practicing it first, trying it?
Or maybe you are meaning that with flaps operable, one could retract them if it started going bad? So, definitely not in that situation where the only option is abort?
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Some of "practicing it" can be done at altitude, like a lot of things we do. In this case, climbs during full flap slow flight would give one an idea of climb capability. It obviously doesn't show whether you would get off the ground or not, but that's not really the problem.

Would I do it? Depends. What day, what conditions, what airplane, what kind of non-SGOTI advice do I have? if there was a mechanic available to fix it, probably not. I'm not a fan of flying unairworthy airplanes.
 
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LongRoadBob said:
Is there even a way to calculate fuel consumption in a trip like that? I’m guessing no.
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Why not? If you look at your tables and graphs, you will see that fuel consumption is pretty much determined by percent horsepower produced which, in turn, is based on power setting. You'd obviously be going slower but the hourly consumption wouldn't be affected that much. Not a flap issue, but I once flew a retract gear down on a 2.4 hour cross country because of a problem. Quite different considerations than a full flap takeoff from a safety perspective but pretty much the same issue from a fuel consumption standpoint.
 
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I can tell you in the Navion a full flap departure has a very slow ground roll, but she climbs like a dog after that.
 
Stewartb said:
Where does it say they’re prohibited? You guys need to learn more about your airplanes!
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I don’t think taking off intentionally with full flaps is necessarily prohibited. But...

Taking off with inoperable flaps, up or down, may be.

I just checked the Cirrus SR22 POH, and in Section 2, “Limitations”, the “Flap System” is required for all operations.

On the other hand, no such Limitation exists in my Sky Arrow POH. Still, were an accident to result, I think there might be a case made for violation of the catch all 91.13 Careless or Reckless Operation.

That said, I can imagine edge cases where I might risk it, but it would have to be a very unusual circumstance.
 
Stewartb said:
Don’t try a full flap departure without practing it first. Not in a Cessna, at least. You can manage it given enough horsepower but it'll surprise you if you don’t know what to expect.
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...but even better is that we have manual flaps :) much harder to be stuck in this situation.
 
If the flaps do not work the plane has inoperative equipment. It is illegal to fly.
 
Challenged said:
Would you be comfortable with a full flap departure in a situation like this? Would you leave the gear down to help keep the airplane slow? Would you have flown a long trip in that configuration, or just fly back to your home base?
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These are the kinds of temptations that should just make you lie down until they go away. Apply the newspaper accident article test.

Challenged said:
Would you just leave the plane there and try to get a mechanic there to look at it at some later date?
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This.
 
Would I take off with full flaps? I've done it, so I'd definitely consider it. Would I take off with full flaps that I could not retract and then try to actually go somewhere that way? I do not think I would. Ground the plane and get it fixed is what I'd do. If I was in the middle of nowhere at the time then I guess I'd be spending some time in the middle of nowhere. Flying places GA will do that once in a while.
 
Probably the best know and most respected flight instructor in Alaska history trained me in full flap takeoffs to prepare me for short field last moment go arounds. What I learned was a new technique that applies nicely to soft field ops. Should a guy just go out and explore it on his own? Probably not. That’s why we seek advanced training. Subsequently I’ve got a couple of BFR instructors who also train full flap ops not addressed in the POH. The only limitation regarding flaps use in my plane is flap extension speed. I can fly all I want whenever I want with as much flap as I want as long as I don’t exceed flap speed.
 
Stewartb said:
Probably the best know and most respected flight instructor in Alaska history trained me in full flap takeoffs to prepare me for short field last moment go arounds.
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The CFI doesn't teach flap retraction on a go-around (OP can't retract)?
 
If it was in the flat lands with few tall buildings I'd fly the 10 minutes home like that. If there was rising terrain or obstacles I'd wait for a mechanic.

My plane climbs like a bat out of hell with 0 flaps, but with full flaps it seems to want to get back to to hell.
 
As has been mentioned, an inop system like that makes it illegal, and the hypothetical accident report would incorporate that. Besides the risk of personal injury, there's also the risk of damaging the flaps themselves. Cessna flaps are famous for cracking skins, and it's caused by repeated power-on flaps-down stuff like slow flight training. The prop blast pounds those skins. They're not cheap to replace.

In my experience, we had one failure like that, and it was a broken microswitch on the flap selector behind the panel. We had no other electric flap problems in several airplanes over thousands of hours because we checked the rigging of that switching at 200-hour intervals, and didn't spray LPS or other spray-on lubes on the flap jackscrew. A bit of oil on a clean rag, wiped onto the screw like Cessna says, prevents oil getting into the jackscrew travel limit microswitches. Oil in them will cause all sorts of failure modes.
 
dtuuri said:
The CFI doesn't teach flap retraction on a go-around (OP can't retract)?
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He had me land as short as possible on a shortish strip with tall trees in front of me, come to a full stop, and do a takeoff without touching flaps or trim used to land. Over and over again until it was comfortable. It requires adequate horsepower and lots of arm strength and that lesson has paid dividends many times. Would I take off and fly home that way? I would if I needed to get home.
 
Stewartb said:
I would if I needed to get home.
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Caution: incipient stage of Get-There-Itis.

My previous post was if it was close, flat, and obstacle free. Those are different considerations than getting to a meeting or a dinner date, right?
 
I've done a full-flap takeoff accidentally, on a touch-and-go, when I thought I was moving the flap lever from the "neutral" to the "up" position for the takeoff, but I was actually moving it from the "down" position to the "neutral" position so they were still just down. Was airborne before I figured it out. I've tried to be more diligent since then about always returning the lever to "neutral" after a change...

It wasn't any different than the first few moments of a go-around, and was alarming only because it was unintentional and unexpected. It's good to know the plane can do it. But I don't think I'd fly knowing they were stuck down. Stuck up is one thing, but stuck down is another.
 
With full flaps the mains come off the ground before the tailwheel on mine. It took some dual with an experienced instructor before I was comfortable with full flap takeoffs in the Husky.

You wouldn't be catching me doing full flaps TO in a 150 hp 172 or Cherokee. I don't think there's enough power to overcome the drag.

Here's a vid someone posted:

 
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If your type is physically capable of having an asymmetric flap deployment, I'd be concerned one side could come back to life at an inopportune moment.
 
I’ve done it while I was putting in my required hours for insurance. My instructor was with me and we landed and taxied back for takeoff. I forgot to put the flaps back up and it did react differently. The instructor just mentioned that I need to check things before takeoff next time.

It wasn’t a big deal.
 
The flaps on my airplane are mostly just for looks, so taking off full flaps wouldn't do much harm. That handle sticking up next to my leg might be annoying, though...
 
kath said:
I've done a full-flap takeoff accidentally, on a touch-and-go, when I thought I was moving the flap lever from the "neutral" to the "up" position for the takeoff, but I was actually moving it from the "down" position to the "neutral" position so they were still just down. Was airborne before I figured it out. I've tried to be more diligent since then about always returning the lever to "neutral" after a change...

It wasn't any different than the first few moments of a go-around, and was alarming only because it was unintentional and unexpected. It's good to know the plane can do it. But I don't think I'd fly knowing they were stuck down. Stuck up is one thing, but stuck down is another.
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Aha. You, too, have a failed flap system. That switch has a spring inside it so that it cannot stay in the down position. The spring is broken. Some earlier switches had the switch sprung back to center from both up and down; those systems used a slip clutch in the jackscrew drive instead of travel limit microswitches. Pre-1968 or so.

The switch in yours is to prevent application of full flaps unless you are demanding it.
 
My V35 Bonanza will climb with full flaps and gear down at around 500fpm. That's at sea level and not very hot day, and just me on board.

Having said that, I'd not attempt to fly back this way. Why start a possible accident chain?
 
Mike I said:
If your type is physically capable of having an asymmetric flap deployment, I'd be concerned one side could come back to life at an inopportune moment.
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Most have a flap motor in one wing and cables from the bellcrank on that side over to the other. Assymetric deployment or retraction requires a failed cable. That can happen anytime to any airplane that isn't properly inspected long enough to let cables get worn that badly.
 
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There is also a trick to make flaps working again on a Bonanza - raise the armrest between the seats and slam it down. The flap motor is just underneath it and it can help in some cases.
 
A Grumman Tiger will take off with full flaps.................at least that’s a friend told me. :)
 
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