flyboy1963

flyboy1963

Well Known Member
Okay, new RV-9a owner here....but last week doing my first flight in a month, my walkaround included sluicing a lot of wet frost off the entire plane.
With the opportunity to run my hands over the entire thing, I had the urge to squeeze the trailing edge of my lowered flaps.
Yup....crunch, crunch, went the ice inside! I see no big structural or aerodynamic problem, except that a LOT of water could swell as ice and start to pop rivets!!! ....ditto ailerons, not to mention the imbalance and flutter possibilities.
I'm going to add drain holes along the bottom edge. I find me and everyone else catches their toe on the flap if boarding with it in the up position, so I tend to leave them down until after startup.
Yes, best to raise them prior to start, but could need the battery juice when temps are below freezing, right?
so what's the consensus here?....to raise, or lower???

..by the way, there was frost on the BOTTOM of the wing also!...don't be fooled. ...the poor guy at the FBO had to de-frost :) an entire Dash -8....by had!
 
When I park at an air show or where people are going to be around the planes I leave the flaps down. On the leading edges I have lettering that says; "Please Look, But DO NOT touch. It can only be seen with the flaps down.
 
My usual process is:

1) land with flaps
2) After turning off runway, retract flaps to avoid prop kicking up rocks
3) At shut down, extend flaps to facilitate getting out of airplane
4) Once parked, retract flaps because I think it looks better

On startup:

1) If I am by myself, I will leave flaps retracted otherwise, I'll extend them for a passenger to avoid the danger of them damaging them.
2) before engine start, retract them.
 
If you visit an airshow or other event in which a flock of RV's participate, you will note the flaps down position on the majority of RV's present. Airshow or not, my unocccupied RV is almost always parked flaps down, even inside my hangar. Sooner or later you will step aboard your RV and retracted flaps require a larger leg reach thus making it harder to find and establish a solid footing on the relatively narrow wingwalk. I have found this to be so on both nosewheel and tailwheel equipped RV's. Those who are more nimble or athletic may disagree. Its all good.

Picture from Van's website:

qzezif.jpg
 
The main reason I'd leave them down is to make it harder for some kid climbing onto your airplane (without you there) to step on the flap. I've seen it happen.
 
I leave them down and have on the startup check list to retract before taxi. Down is less likely to get damaged with people around the plane (my opinion)
 
Kids and unresponsible Mothers

I had my RV4 on display at a large regional airshow. I opened my canope and went to get a soda, when I came back to my plane there was a boy sitting in my cockpit. A big boy, maybe 150#. He did not experience my best side, when I told him to immedately remove himself. His mother stepped up and said she told her son, it would be OK to sit in the display plane. There was DUSTY FOOT PRINT on my flap (fortunately no damage). I explained the offence to me was the same as it would to them, coming home to find me sitting in their living room watching TV and drinking a beer from their refrigerator. Enough of my rants. I now leave my flaps down to protect them when around people.

Steve
 
I was giving rides to a science class that was studying aeronautics and forgot to lower the flaps before deplaning. The 200+ lb tackle stepped out on the flap with his cowboy boots as he was getting to the ground. I felt my heart skip a couple beats but could find no damage.

I always leave them down, always when parked.
 
Flap on flaps

Hi guys and gals.
As this is going to be my 4th year parking homebuilts at SNF I really look forward to eyeing the RV population for helpful info on my RV-7 build.
As for flaps, please taxi with them retracted, as it was mentioned debris (FOD) will be an issue. after shutdown, whatever works best is great with us at HB. Look forward to meeting some of you folks there.
Jerry Fischer
Winder Ga
Canoe now upright and bottom half totally riveted! YeHa:p
 
Flaps Down on the Ground

I used to raise mine after clearing the runway, then lowered them again before shutdown, then raise before engine start and taxi. After my first bought with a stuck flap motor due to worn brushes, I decided that the flap motor is a limited life item, and stopped doing the extra cycle - I taxi in with them down, and leave it that way. For folks that will take many years to put several hundred hours on, this might not be a problem, but with the rate I fly, I worry about wearing things out. I haven't had any debris damage from taxiing with them down.

Paul
 
My flap motor is over 66 years old and has never failed. Sometimes it gets tired, but never failed. And it even works with a dead battery.
 
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Old Flap Motor

Mel said:
My flap motor has never failed. Sometimes it gets tired, but never failed. And it even works with a dead battery.
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I think Mel and I have the same "Armstrong" flap motor. Mine is north of 50 years old, but has not failed yet!
I always park with the flaps down to preclude unsolicited foot prints imbeded in the upper flap skin. Also, ever see a parked P-51 looking studly with it's flaps down? It just looks cool that way and so does the RV! If I had gear doors, I would lower them too!
 
Land and park flaps full down. Raise flaps to 10 degrees after engine start for takeoff.

Steve
RV-9A
 
Manual flaps here, so no motor concerns, though could see how that might be a consideration with e-flaps.

"Flaps Up" is on my Before Start checklist, and they come up as a part of a flow when clearing the runway, and it's also on my After Landing checklist that follows. I do it the same way whether taxiing back for TO or heading to the barn...partly to avoid dings, partly to keep one habit pattern in place for when I'm doing the taxi-back thing (that's not often, and "Flaps Up" is on the Before Takeoff checklist too, just to be sure!) They go back down after shutdown.

When I started taking my boys (now 8 and 9) up, they initially would wait for me to help them down. After a few flights, their natural "I can do it myself" tendency kicked in, and when I walked around they were already on the ground. Glad the flaps are down then, as I'm sure a couple of size 3 footprints would have been found on the flaps otherwise. :eek:

At least they listened when I taught them to step on the black part, and to always stay behind the wing! ;)

As said earlier, makes it a bunch easier to get in and out, at least in a TW. Seems like a nice idea in an -A as well, so you don't catch your toe on the trailing edge of the flaps on the way in, or with your heel on the way out.

Cheers,
Bob
 
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I park with the flaps almost down. I learned the hard way if the flaps are full down and someone leans on one it can let the outboard leading edge spring up enough to catch the wing skin. Raising the flaps causes a real ugly bend in the skin. I now bring them up just a touch from full down and that won't happen again. I have seen this on several RVs as it is very hard to catch on a pre flight especially if it hasn't happened to you. Don
 
yakdriver said:
I park with the flaps almost down. I learned the hard way if the flaps are full down and someone leans on one it can let the outboard leading edge spring up enough to catch the wing skin. Raising the flaps causes a real ugly bend in the skin. I now bring them up just a touch from full down and that won't happen again. I have seen this on several RVs as it is very hard to catch on a pre flight especially if it hasn't happened to you. Don
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Let me second this. I have an essentially unrepairable skin crease because of this but I hadn't thought of the simple expedient of raising the flaps a bit.

My incident happened during a Young Eagles flight and that incident along with a couple of others had me leaning toward not doing any more of these flights. Maybe I shouldn't be quite so hasty.
 
Flaps down, for all the reasons mentioned by others, plus this one- with the flaps down, nobody can see that your flaps and ailerons are not perfectly lined up! More of an issue with the 3/4/6, but still an issue!

Jerry Fischer said:
As for flaps, please taxi with them retracted, as it was mentioned debris (FOD) will be an issue. after shutdown, whatever works best is great with us at HB.
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Funny you should mention this. At my one trip to SnF ('05) the parkers were insistent on my raising the flaps during taxi. I've never heard of this anywhere else, including 10 years of parking homebuilts at Oshkosh. Where did this idea come from?
 
sprucemoose said:
At my one trip to SnF ('05) the parkers were insistent on my raising the flaps during taxi. I've never heard of this anywhere else, including 10 years of parking homebuilts at Oshkosh. Where did this idea come from?
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They were probably just trying to keep you from sand blasting your flaps. :)
 
Sam Buchanan said:
They were probably just trying to keep you from sand blasting your flaps. :)
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And for that I'm thankful. I'd hate to damage my expensive paint job ;)

There is quite a difference between the soil and sod conditions in FL vs. WI, and this might be something to consider when determining flap position while taxiing.
 
Leave 'em up

I leave them up unless I have someone who could get in easier if they were down. Reason: the trailing edge of the wing (not the flap) on the 9 is unsupported for the last inch or so when the flap is down. I would rather have to repair a flap than a wing. One step at the back edge of the wing and I fear there would be an obvious crease.

Bob Kelly
 
A Lifetime guarantee from a surgeon?

Kyle Boatright said:
My flap motor wore out last summer. I took it to the orthopedic surgeon and now it carries a lifetime guarantee.
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Yeah, Good luck with that!

BTW, another reason for taxiing with flaps up is, It's MUCH easier to tip the nose with flaps down. I've seen several.
 
jetjok said:
Also, ever see a parked P-51 looking studly with it's flaps down? It just looks cool that way and so does the RV! If I had gear doors, I would lower them too!
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Well, sure it looks cool, but the only reason why the flaps and doors are down is because there is no oil pressure holding them up. I hope your "Armstrong" flap motor doesn't lose it's oil pressure!
 
I taxi with the flaps up because I noticed the right one (I think it was) seemed to resonate with the prop when down while taxing. Just don't like seeing that. I always park with them down for all the reasons above.
 
jjconstant said:
the nose-tipping thing...:confused:

Jeremy
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The flaps act like elevators when on the ground. With power applied they can lift the tail and cause a prop strike.
I've seen more than one RV-4 get the prop by doing a run-up with the flaps down.
 
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