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Zero flap take-off's

Use ‘em if you like em’. Just don’t forget to raise them!

0 flap on hard surfaces, 1/2 (manual flaps) on soft/short field. Works a charm in my RV-6.

Full flaps on all landings (unless I’m practicing no flap landings which I do regularly).

While I also practice go-arounds, I *have* forgotten (once) to raise the flaps on a go-around. As it happens I was tired, heavy, at at a DA >6000’ and left the full flaps in while climbing out. With “only” 150hp and a fixed pitch prop, it was pretty obvious pretty quickly *something* was wrong (different). Took me a 20 sec or so to figure it out in my fatigued condition. Still far better climb rate than the 152 I trained in, but just didn’t accelerate to the usual speeds … until I got the handle down. Now I plan to practice some full flap TOs, just so I can recognize (what would be an error) more quickly.

Peter
 
I always use 15° flap for take-off. Less time on the ground, better visibility over the nose, less tire wear. Reason for doing it every time, you establish a routine, thereby lessening the probability of forgetting to raise them.

If you have electric flaps, push the stick to one side and align the flaps with the lowered aileron. This is very close to optimum L/D.

I have learned a lot from Mel over the years and must of read his preferences on this matter before because I do as Mel does. do as you please, we are flying one of the great airplanes ever built, flaps or no flaps on takeoff. ;)
IMG-2368.jpg
 
I always use 15° flap for take-off. Less time on the ground, better visibility over the nose, less tire wear. Reason for doing it every time, you establish a routine, thereby lessening the probability of forgetting to raise them.

If you have electric flaps, push the stick to one side and align the flaps with the lowered aileron. This is very close to optimum L/D.

Same here. I typically use the same flap setting for takeoff and landing….except I don’t use the aileron/flap alignment trick for landings. ;)
 
20 degrees on takeoff? I am curious how effective this is for soft field? Do you have experience using 20 degrees?

Sorry for the late answer.
Yes, I do have experience with Flaps 20 on T/O in the RV-8 and RV-7. The T/O roll shortens and this is more noticable on real soft and wet runways where roll resistance is real high. Transferring weight to the wings early is reducing roll resistance and so increasing acceleration.
Personally I reserve Flaps 20 on T/O for "my worst cases", just before I stop flying alltogether.
 
Same here. I typically use the same flap setting for takeoff and landing….except I don’t use the aileron/flap alignment trick for landings. ;)

I do the 20 degree flap when aligned with full deflection aileron, but I keep doing rolls on final. Go figure. :D
 
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When I started flying my -6 I generally only used 10 degrees on takeoff if I was fully loaded... Full fuel, passenger, etc. Otherwise i'd just leave them up. Lately i've started using 10 degrees on all takeoffs. Tail is up a little faster, i'm off the ground a little faster. Solo with half fuel, even more so.

To the person who leaves the flaps down taxiing in because it's easier to get out afterwards: You'll change that habit the first time you taxi the flap over a runway/taxiway light that you didn't see. I raise flaps on leaving the runway, and put them down again when parking. One more cycle of the flap motor, but the motor is easier to repair than the flap if it hits something.
 
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When I started flying my -6 I generally only used 10 degrees on takeoff if I was fully loaded... Full fuel, passenger, etc. Otherwise i'd just leave them up. Lately i've started using 10 degrees on all takeoffs. Tail is up a little faster, i'm off the ground a little faster. Solo with half fuel, even more so.

To the person who leaves the flaps down taxiing in because it's easier to get out afterwards: You'll change that habit the first time you taxi the flap over a VASI light that you didn't see. I raise flaps on leaving the runway, and put them down again when parking. One more cycle of the flap motor, but the motor is easier to repair than the flap if it hits something.

How did you get that far off the runway to hit a vasi bar? Or did you land in the grass?
 
If you consider that from ground level to some arbitrary altitude that is considered safe for a turn back, whatever it is, you translate through that altitude faster with 0 flap at Vy because you have better l/d. The downside is an increase in takeoff distance. If you have obstacles, a shirt runway or rough terrain that you want to lift off from at the lowest possible speed then flaps down at Vx will maximize your climb angle and minimize your runway distance, but you will spend more time getting to a safe altitude. Nothing is free.
 
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I am in the camp of using 15 degrees of flap for normal takeoffs. Unloads the wheels earlier, saves wear and tear on the tires, etc. As soon as I have a positive rate of climb I retract the flaps.
 
Flap position on take-off

With the recent impossible turn incidents out there, I wanted to better understand my flap take-off options. Yes, I know our RVs don't NEED flaps on take-off (Unless soft field) but maybe that's the point or at least one. As I age, I would like to use a common procedure for take-offs to reduce at least one process for me. It seems there is little to no downside to using partial flaps on take-off. Yes, I can forget to raise them but most of us or at least for me have an EFIS that warms me when this occurs. (Yes, fully admit this occurs occasionally on take-off especially when I need to react to another issue) I fly from a fairly short field and by muscle memory (sailplane flying) the two hundred straight still rings out. It seems that an engine out during climb out is our worst-case scenario (close) and having the flaps partially down leaves one less thing to review as you go through your trouble shooting. I estimate that an engine out at 250 - 300 ft I have 8 secs to trouble shoot before finding a place my airframe will end up. And yes, I use half-flaps for take-offs, extending the glide 150 ft will not help 99% of the time for at least my airports I use.
 
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Same

Same here. Have never felt the need, and I’d be worried I would overspeed them.

other than practicing short or soft field takeoffs during transition training, I don’t think I’ve ever made a takeoff with flaps in my -9A. Can’t think why I would do that…seems like it would add unnecessary complexity to the process.
 
On my RV-9A, a no flap takeoff will get the nose so high that it will completely hide a narrow runway. I occasionally practice a no-flap takeoff on a wide runway, but that's never standard.
 
Interesting

I have never seen the need to do partial flap takeoffs in my -10. Yes, I have tried them. Normal takeoff shows well over 1000 fpm initial climb AND rapidly accelerating through 90 knots; it would be very easy to over speed the flaps and the nose high attitude required to prevent that acceleration would be…uncomfortable…for most passengers, IMO.

That said, I generally fly out of a small, paved runway (~2800’) with a 300’ ridge off of one end. No issues with flaps zero. After CI I will do more testing and see if half flaps are something to consider again…
 
Steve Smith (-10 airfoil designer) has suggested here on vaf that best rate of climb for the 10 is with flaps in trail (normal cruise is -3 deg flaps in reflex). Ever since Vans removed the speed restriction to flaps in trail, that’s my standard take off configuration.
 
20 degrees on takeoff? I am curious how effective this is for soft field? Do you have experience using 20 degrees?

I have electric flaps and I have them set up to deploy in 10 degree increments. I use 20 degrees on take-off every time. I find it brings the tail up a little faster (not much, but a little) and it provides the shortest take-off roll.

During the test phase we checked T/O roll with a person on the ground using a measurement wheel. One run after another in the same conditions - Pilot, half gas, sealed runway, zero wind with the same starting point each time (1422 lbs):

Flap 0 - 182 m (597 ft)
Flap 20 - 140 m (460 ft)

Flap 10 was only marginally shorter than no flaps while Flap 30 and Flap 40 were much longer than Flap 20. I can't find the test report right now but I have the exact figures listed there if anyone is interested.

This was as expected as I learned a long time ago that Flap 10 makes almost no difference to T/O performance. Its the same on the Piper Lance... were we found the first notch to be all but useless.

Almost all my T/O's are from grass as we have no sealed runways at our home base.
 
On my RV-9A, a no flap takeoff will get the nose so high that it will completely hide a narrow runway. I occasionally practice a no-flap takeoff on a wide runway, but that's never standard.

I often fly a -9a also, but I never climb with the nose so high that I can’t see over it.. every RV I fly, we takeoff no flaps, accelerate in ground effect to 110 or more, then allow the plane to climb. Keeps great visibility and energy incase the engine quits..
 
Only for soft or short field. I fly IFR so I like to keep my “flow” the same and my goal is to accelerate ASAP and have a low workload departure. If I lose power at a low altitude I will have more energy and options with the wing clean. If flaps are needed for a turn, drag or landing I’ll drop ‘em.

Do some flight test and see what your airspeed and altitude is with and without flaps for takeoff. How is the airplane situated in relation to the departing runway? Does it put you in an advantage or give you less options? There is so many different scenarios.
 
Just wondering what flap settings pilots are using, currently I am using 10 degrees for my recently completed RV14A.

Is a zero flap take-off considered acceptable?

John

Zero. The thing takes off like a homesick angel without flaps, so never felt the need. I've 10 and 20%, but really can't tell the difference. RV flaps seem much more like speed brakes to me.
 
I seldom use any flaps for T/O..except short/soft operations. When I first started flying my -4, I used 10-15 degrees for T/O. The RV's just don't need it for normal operation, and your at flap retraction speed before your out of the pattern. When I land, flaps to zero while rolling out, and they stay there until the next time I set up to land. Just my preference, but I bet I'm not alone. I fly a -4, not a -14, so I cant share the differences.
Same.

RV-4,, never use flaps for T/O: Solo.
However if I have a "large-framed" passenger in the back, I will use one-notch.
Helps getting a heavy tail off the ground
 
I often fly a -9a also, but I never climb with the nose so high that I can’t see over it.. every RV I fly, we takeoff no flaps, accelerate in ground effect to 110 or more, then allow the plane to climb. Keeps great visibility and energy incase the engine quits..

No, it’s not the climb where you lose sight of the runway, it’s on rotation.
 
To flap or not to flap....that is the question.....

With the recent impossible turn incidents out there, I wanted to better understand my flap take-off options....

My field elevation is 5190 msl. After testing during Phase 1 and experimenting during Phase 2, I found that one notch of flaps (20 degrees) gave me a shorter take off roll and a better deck angle leaving the runway. My usual procedure is to level off immediately after leaving the runway gaining airspeed, slowly retracting the (manual) flaps and pulling up to climb speed (either best ROC or best angle, depending on needs at the time). So: since it is part of my departure routine to retract the flaps I have rarely forgotten to retract them. Should the "impossible turn" occur, the flaps are retracted.

Full flaps on final for better nose-down attitude and shorter landing roll. Retracted immediately after the tail comes down to plant her firmly on terra firma. I know the general rule about not touching anything until leaving the runway so as not to inadvertently retract the landing gear but SuzieQ's gear is down and locked, three green! She also likes to land tail-low wheel landings better than three point. :)
 
Getting to the impossible turn sooner

For me the goal is to get to the point where the impossible turn becomes possible as fast as I can. Given the speed vs altitude is a trade off I would think doing this at the best L/D is what I want. Higher speed means increased drag and 110 knots vs 80 knots seems to be adding ~90% increased drag and therefore delays my ability to get to the impossible turn decision height. (Granted at a higher speed the decision height is lower but I’ve given up some of my kinetic energy doing this at a higher velocity)

Initially I was taking off with flaps zero but after awhile started experimenting with flaps 20 and liked the overall performance. Once at 400 ft I retract my flaps and continue the climb at 110 knots.

Warning I’m not an Aeronautical Engineer (Chem E) and have not slept in a Holiday Inn for a long time.
 
Turn

For me the goal is to get to the point where the impossible turn becomes possible as fast as I can. Given the speed vs altitude is a trade off I would think doing this at the best L/D is what I want. Higher speed means increased drag and 110 knots vs 80 knots seems to be adding ~90% increased drag and therefore delays my ability to get to the impossible turn decision height. (Granted at a higher speed the decision height is lower but I’ve given up some of my kinetic energy doing this at a higher velocity)

Initially I was taking off with flaps zero but after awhile started experimenting with flaps 20 and liked the overall performance. Once at 400 ft I retract my flaps and continue the climb at 110 knots.

Warning I’m not an Aeronautical Engineer (Chem E) and have not slept in a Holiday Inn for a long time.

There is a ton of discussion on “the impossible turn”, and practicing it. Personally, I will demonstrate it to students but it is more to show that it may NOT be the right thing to do. You can train it all you want but when it actually happens, your estimated “safe” altitude will be insufficient. I am NOT saying it cannot be done, only that pre planning it for practice, is not realistic.

As far as performance goes, these airplanes will generally reach a “safe” altitude in a very short time, flaps zero or half flaps. The “danger zone” is very short, either way…
 
I think as a couple posts mentioned holding the aircraft down and accelerating does not improve your options for a return to the airport. I suspect a climb at best angle would give you the best return probability but will result in an uncomfortably high nose attitude for some. I climb at best ROC to about 1000 feet then accel to my cruise climb speed. If I accelerated to cruise climb right away I don’t think the extra speed is going to offset the increased distance to get back to the airport.
 
To flap or not to flap.......

Personally, in my -3 I do not use flaps for takeoff, unless it's a cool day. Then it's 10 degrees and best climb speed which is 80kts, but I increase that to 90kts for safety margin so I can experience the fantastic rate of climb of the RV-3. :D Landings are full flaps and I land tail low and raise the flaps after touchdown. (They are electric). I personally feel that the -3 is the easiest to land, very straight forward with no surprises, but that's just my opinion.
 
Landing an RV-4

Personally, in my -3 I do not use flaps for takeoff, unless it's a cool day. Then it's 10 degrees and best climb speed which is 80kts, but I increase that to 90kts for safety margin so I can experience the fantastic rate of climb of the RV-3. :D Landings are full flaps and I land tail low and raise the flaps after touchdown. (They are electric). I personally feel that the -3 is the easiest to land, very straight forward with no surprises, but that's just my opinion.

The -4, being the Big Brother of the -3, is pretty easy to land as well. I remember early in Phase 1, when I came in to land, I found I was "stirring the pot" to feel where the runway was. One day I thought 'why am I doing that?' and just slowly pulled back once in ground effect. Squeeker! Oh. That's how to land an -4. I must say, it is easier to land a -4 than a J-3 Cub.... Don't tell her I said that.....;)
 
No, it’s not the climb where you lose sight of the runway, it’s on rotation.

I’m confused.. we must fly differently. I get the nosewheel off the ground as soon as I can lift it, (probably before 20 knots) then keep it one inch or so off until the plane lifts itself off the runway. Think soft field technique. I thought that’s the Vans recommended way to fly the “a” models?
 
Flaps up TO

RV9A at Reno NV, field alt 5020'. No flaps for takeoff, full for landing. Seems to still work after 16 yrs and 2585.0 hrs. (My motto: Don't mess with what works".) Dan from Reno
 
8A, 180 HP and constant speed - I always take off with flaps up. Sometimes I rotate firmly into a climb with the AOA at the top of the green (with just me and 3/4 fuel it gives approximately 20 degrees nose up) and am usually climbing through 500 AGL at the end of the 3100’ runway. At 500 I pitch for 95. A few times I pitched for 85-90 at 500 and was at 2200 on downwind parallel to the arrival threshold.
 
I’m confused.. we must fly differently. I get the nosewheel off the ground as soon as I can lift it, (probably before 20 knots) then keep it one inch or so off until the plane lifts itself off the runway. Think soft field technique. I thought that’s the Vans recommended way to fly the “a” models?

You should not have to lift it. All takeoff's are soft field.. Hold full elevator until the nosewheel lifts and clears the ground, the aircraft will fly away when it is ready. Hold flat to increase airspeed after lift off.

But this goes back to when you were taught to hold neutral elevator and wait for rotation speed, then hoist the Warrior/172 off the ground.

I still see many RV-A owners take off like they were still in a Warrior.... Very sad and hard on the nose wheel$$$.

Van designed the aircraft. You should fly it based on his instructions. There is a reason for his instructions and it is a design compromise. Don't ignore it!!

But if you decide to ignore it, Van's has designed a nose gear that may allow you to fly it like a Warrior/172. It will just cost you more money and added weight....... all the things Van was trying to avoid to start with.

Will someone please post Van's instructions (speeds) on when to rotate A models? 6,7,8,9. Maybe I am missing something and have been flying my 6A wrong all this time.
 
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The nosewheel should be used like a kickstand on a bicycle - only when you can't avoid it any longer.
 
Do you notice any difference in ease of lifting/holding the nose wheel off with flaps down vs with flaps up?
 
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