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Use of flaps for takeoff

B

bob888

Well Known Member
I would like to know what others are doing with flaps for t/o. Routine, short field, soft field...documentation? I have tried to figure whether 15deg flap shortens the takeoff distance but can't come to a conclusion.
 
Routine - no flaps
Short field or just for fun - half flaps. It is like riding an elevator.

Just remember to tuck them away shortly after take off as your speed will quickly build up.

Carl
 
You will no doubt get many responses. Here's mine.

I use 15° flap for all takeoffs. Reasons? Less ground roll relates to less tire wear and quicker obstacle clearance. If I do it every time, I develop a habit so I never forget to raise them after takeoff.

My home field is 1500' long, so I'm always after short field performance.
 
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Mel said:
I use 15? flap for all takeoffs. Reasons? Less ground roll relates to less tire wear...
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Obviously this is true in an absolute sense. But has anyone ever compared tire wear when rolling, compared to the first half-second of landing, when they're sliding? and then, asked to provide braking force? My uninformed guess would be that take-off wear is negligible compared to landing wear.
 
BobTurner said:
Obviously this is true in an absolute sense. But has anyone ever compared tire wear when rolling, compared to the first half-second of landing, when they're sliding? and then, asked to provide braking force? My uninformed guess would be that take-off wear is negligible compared to landing wear.
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I fully agree. That is NOT my reason for using flaps, it's just a small added bonus. As I said, the primary reason for using them every time is that I have developed a routine which makes it easier to remember to raise them on climb out.
 
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Mel said:
I fully agree. That is NOT my reason for using flaps, it's just a small added bonus. As I said, the primary reason for using them every time is that I have developed a routine which makes it easier to remember to raise the on climb out.
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And you always remember to raise the gear too.....:D:D:D
 
Always use 10?, airplane gets off quicker.

Its added lift, very little drag.

Retraction is automatic with switch near throttle.
 
I also use 15 as standard since my home strip is 2000' grass and not as smooth as it might be - not to mention 5000' DA in the summer. I also like the routine of doing it the same way every time. I can't see any advantage in NOT using 15.....

IIRC, there is a warning somewhere that you should NOT have the flaps fully up for TO (ie Reflex) but use 3 deg (ie trail) for "flapless" TO or you get an excessively long run.
 
paul330 said:
IIRC, there is a warning somewhere that you should NOT have the flaps fully up for TO (ie Reflex) but use 3 deg (ie trail) for "flapless" TO or you get an excessively long run.
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Never heard that before. Near sea level I takeoff with the flaps in reflex all the time and the takeoff run is not excessive even at gross.
 
Mel said:
You will no doubt get many responses. Here's mine.

I use 15? flap for all takeoffs. Reasons? Less ground roll relates to less tire wear and quicker obstacle clearance. If I do it every time, I develop a habit so I never forget to raise them after takeoff.

My home field is 1500' long, so I'm always after short field performance.
Click to expand...

Love that way of thinking, Mel. Never thought of that rational, but I will be giving it a try. Sounds like a win-win!!
Jim
 
15 degree flaps on take off

I did my transition training with Mike Seager years ago and we used 15 degrees of flaps for take off. Getting to altitude quicker adds some margin of safety in case of a emergency during takeoff. 1000 hrs later and all is good. Not saying others are wrong just offering my thoughts behind it.

Don Orrick 40010
N410JA
 
I use 15 for every takeoff. My reasons are standardization and being better prepared if there is an emergency between rotation and 1000ft where I retract them. 15 is good for close tight manuevering, and one tap away on the preselect to full which is preferred for emergency landing on or off field.
 
15 degrees

when taking off behind friends, gets me up and out of their propwash noticeably quicker.
 
I use 0 deg (in trail) for normal takeoffs, hard surface, 3000'+ runway.

I use 15 deg for grass and/or short/obstacle. All my takeoffs at home airport are done this way, rarely elsewhere. I have no numbers to support this approach.

Climbs are in reflex

I use a before TO checklist printed on panel so I don't forget to set it.
 
What Ironflight is referring to is that I have a landing gear switch, warning light and horn in my RV-6. It keeps me in practice for when I fly retracts.

The light $ horn are triggered by my flaps. On takeoff if I "raise" the gear with the flaps down, it will alert me.
 
midwest rv-10 said:
I did my transition training with Mike Seager years ago and we used 15 degrees of flaps for take off. Getting to altitude quicker adds some margin of safety in case of a emergency during takeoff. 1000 hrs later and all is good. Not saying others are wrong just offering my thoughts behind it.

Don Orrick 40010
N410JA
Click to expand...

you will get off quicker with flaps, but you will NOT get to altitude quicker. Rate of climb is better with flaps 0 - (T-D)/W. The angle is not as steep, but the higher speed (assuming you do use the Flap 0 best climb speed) gives you a better rate of climb. So if you want to get to a safe altitude in the minimum time, 0 flap is better. If you have a short field or obstacles, takeoff with flap is better.
 
Flaps

A Careless pilot I know very well forgot to retract them before take off once, during phase one. 2nd flight I think. 40 degrees! The plane was very light. The deck angle was tremendously steep and I think any reasonable obstacle would've been cleared in a short distance horizontally. As I said the plane was quite light and it has a 214 hp Lycoming with CS Hartzell BA prop. It seemed hard to stay under 100, pulling up so high - don't know how the guy could be so stupid! Somebody on the ground said they saw nothing but the bottom of the airplane.
 
I agree with the idea that it's a good habit to get into to have the flaps down and then retract them as you pass through 75 knots. The Rv10 does accelerate very quickly with the IO-540 up front so you need to get those flaps up quick or you will overspeed them. I have an Air switch on my flaps and above 96 knots power is cut off to the Flap controller. It has caught me out a few times like when letting the speed build up on the base turn and then having to hold the nose up to slow down below 96 knots to get the flaps to work. I have been consciously making myself slow to below 94 knots on late downwind so that I can get the flaps down before I point the nose at the ground.
Cheers

John MacCallum
41016
VHDUU
 
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