Why bother with flaps on takeoff?

Salty

Salty

Touchdown! Greaser!
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Salty
My mooney stall speed with takeoff flaps is only about 5mph higher, so with a 10,000 foot runway, why bother with flaps? Or even 6,000 for that matter. Sure, shorter fields it's a no brainer, but when the trees are not a factor, why not just get the speed up to Vy and fly?
 
cause it will increase your angle of attach....lower your stall....possibly reduce the takeoff roll....and make climbing a little easier.
 
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Try it, then get back to us and let us know how it worked out, or how it felt to you.
 
Checkout_my_Six said:
cause it will increase your angle of attach
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That makes me want to ask another question. I know this is a logically sound statement, but, if this is true, then why do you have to trim up for each notch of flaps in a mooney?

....lower your stall....
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5 whole mph. woooo!
possibly reduce the takeoff roll....
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Definitely true, but again, with twice as much runway as needed, does that matter? Maybe getting off the ground asap is a good idea for other reasons...

and make climbing a little easier.
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how exactly?
 
Zeldman said:
Try it, then get back to us and let us know how it worked out, or how it felt to you.
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It's a theoretical question more than a practical one.
 
Sometimes I do it, some times I don't.
 
any time you are given a 5kt safety cushion.....take it. It may mean the difference at impact....should it happen.
 
455 Bravo Uniform said:
If you need to get back down on that 10k or 6k ft runway, you're gonna wish you had that 5 kts cushion?
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If the engine shuts off, yeah, you're right. But at Vy I'm at least 25 mph faster than stall speed....
 
Runway length and stall speed aren't the only things affected by flaps. Your climb will be steeper and have a higher rate without flaps.
 
MauleSkinner said:
Runway length and stall speed aren't the only things affected by flaps. Your climb will be steeper and have a higher rate without flaps.
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In general:

Flaps- Off the runway sooner, but shallower lower rate climb off the runway

No flaps- Longer on the runway, but steeper higher rate climb once off
 
I doubt that. What does your POH say about takeoffs over obstacles?
 
Stewartb said:
I doubt that. What does your POH say about takeoffs over obstacles?
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It says getting off the ground sooner with flaps is more advantageous than the steeper climb without when dealing with low, close-in obstacles. It says the opposite when dealing with higher, more distant obstacles.
 
I suppose I should define steeper climb, in this instance I was meaning higher FPM. So bad word choice, I should have said higher rate of climb.
 
My Cherokee 140 POH recommends no flaps on takeoff which I thought was interesting.
 
SR20/22 normal takeoff is usually with flaps 50%. You can takeoff with flaps 0 but we usually use 50%.
 
Flaps get you off shorter, but then you climb at a slower rate in my Husky. If you take off with flaps, you have more trimming to do as you retract them. Nice even climb out to cruise without them. Try both, and take your pick. If you can't decide, alternate.
 
My 182N, I put in 10 dog every now and then. I get to altitude pretty damn quick.
 
Salty said:
That makes me want to ask another question. I know this is a logically sound statement, but, if this is true, then why do you have to trim up for each notch of flaps in a mooney?
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The flaps affect the airflow around the horizontal stabilizer. In a low wing extending the flaps will reduce the down load on the tail, causing the nose to go down (because the tail is going up).
 
On checklist items that are not "required", I tend to err on the side of doing hem for consistency sake. I fly a PA46 and would not dream of rolling on take off without the first notch of flaps in...after missing it once.

Not doing these and giving your self the opportunity to miss it when you need to have the flaps in is, in my opinion, reaching a new level of complacency.
 
so what happened.....when you missed the flap setting?....a little longer roll than expected? :D
 
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CC268 said:
My Cherokee 140 POH recommends no flaps on takeoff which I thought was interesting.
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That’s standard. Same for a Skyhawks. But not every airplane is a Cherokee or a Skyhawk. Some, including Mooney’s, call for flaps for normal takeoff as SOP. The manual even refers to them as "takeoff flaps." Different airplanes, different POH-recommended procedures,
 
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Salty said:
My mooney stall speed with takeoff flaps is only about 5mph higher, so with a 10,000 foot runway, why bother with flaps? Or even 6,000 for that matter. Sure, shorter fields it's a no brainer, but when the trees are not a factor, why not just get the speed up to Vy and fly?
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My SOP is no flaps for takeoff in my M20C, unless I am loaded heavy. This was true taking off over trees at my original 3000' home, then my 5000' home with long, open approaches at both ends, and now my current 3200' base with one fairly open approach. It's rare even in the summer to not be off the ground in 1000 feet . . . A simple Vx climb easily put me 250-300' agl by the end of the 3000' runway, then relax to Vy and go to altitude.
 
Capt. Geoffrey Thorpe said:
I guess it depends on the airplane. In a Cessna 120, I never bothered with flaps at any time.
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That's a defective airplane. Haven't you been around these boards long enough to know that you have to land every airplane with full flaps every time, or you mess up the whole space-time continuum, or something like that?

:confused:o_O:eek:
 
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