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Any Advantage No Flaps Takeoff?


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#1 201er

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Posted 23 October 2012 - 03:35 PM

Since I am accustomed to flying out of small fields, I always use take off flaps. Out of habit I usually end up taking off with flaps on long runways as well. Occasionally I've tried taking off without flaps but it doesn't seem to help anything and in fact makes things worse. To me it seems that spending more time on the ground before rotation is more stress on the gear. Also getting in the air quicker reduces frictional drag of the wheels for acceleration. So is there any good reason NOT to use takeoff flaps regardless of runway length?

#2 1964-M20E

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Posted 23 October 2012 - 03:42 PM

I guess it is all what you are used to and what you were taught. The reasons you mention seem like a good justification to use flaps on takeoff.

I learned at a medium sized airport with long paved runways the shortest being 3000’. I only used flaps when doing short and soft field practice. I regularly operate off a 3000'+ grass strip and I do use flaps on the takeoff I just need to remember to retract them once I’m airborne.

John
current 1967 M20F
former 1964 M20E

#3 Piloto

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Posted 23 October 2012 - 03:57 PM

I never use flaps on take off. I found the rotation transition to be smoother with minimum trimming. Also on wavy runways is better not to use flaps to avoid nose wheel bouncing. However on short runways (2000ft or less) I use flaps. On landing if there is crosswinds or gusty conditions I retract the flaps just before touch down to get a firm grip on the runway, specially on wet or iced runways. This keeps the plane from weather vaning into the crosswind or bouncing due to gusty conditions.

José

#4 BigTex

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Posted 23 October 2012 - 04:01 PM

I personally don't use them unless there's a need. I find that without them I have better elevator authority, smoother takeoff AND since I have a 100 MPH speed limit on my flaps, it's one less thing to worry about when swinging up the manual gear.
Gary Franks
Based at: KDTO, Denton Texas
1965, Mooney Mark 21 Model: M20C

#5 Hank

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Posted 23 October 2012 - 04:27 PM

My home field is 3000' with trees at both ends. My normal takeoff is Flaps UP, unless I'm heavy. Sometimes I still use Takeoff Flaps when leaving long [5000 or more] runways when heavy just from habit. "Heavy" meaning 4 adults, or loaded with the wife for vacation, not just an overnight trip.

When I visit a nearby 2000' grass strip, I never go in or out heavy, and I use Takeoff Flaps.

As noted above, the transition from ground to air is pretty seamless, smooth, with good authority.
--Hank
1970 M20-C

#6 bluehighwayflyer

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Posted 23 October 2012 - 04:58 PM

Although I have practiced no flap takeoffs, my routine is to use takeoff flaps for all of the reasons that Mike stated. They lower stall speed, after all. I'm not sure how that can't be a good thing during such a critical stage of flight. Although I have electric landing gear on my 201, I have also found that takeoff flaps are very useful in manual gear Mooneys to help keep the speed down after takeoff as an aid in gear retraction.
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Jim R.

#7 bd32322

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Posted 23 October 2012 - 09:34 PM

Although I have practiced no flap takeoffs, my routine is to use them for all of the reasons that Mike stated. They lower stall speed, after all. I'm not sure how that can't be a good thing during such a critical stage of flight. Although I have electric landing gear on my 201, I have also found that takeoff flaps are very useful in manual gear Mooneys to help keep the speed down after takeoff as an aid in gear retraction.


No flaps most of the time - unless the runway is short or has obstacles - the extra stall protection is worth it when flying close to Vx.
But I wouldnt use it for all takeoffs - because the aircraft seems to jump up like a suprised cat jumping on all fours ! (yes I pull on the wheel before 60 KIAS)
The rotation is much smoother without the flaps and you can keep adequate speed above stall with a long runway and no obstacles...

#8 jetdriven

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Posted 24 October 2012 - 12:29 AM

For an air race start it has an advantage. No configuration change, no pitch change, no messing with switches right off the runway.
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Byron
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#9 Lood

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Posted 24 October 2012 - 07:01 AM

Also only use flaps on shorter fields, if there are obstacles and when heavy. Agree that the transition is smoother without flaps and the initial climb out better.

#10 N201MKTurbo

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Posted 25 October 2012 - 01:34 PM

I only use flaps for take off on very short runways. Same as mentioned above, no configuration change and smoother take off. I bought my first Mooney in 1984 and stopped using take off flaps about two weeks after that.
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#11 201er

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Posted 25 October 2012 - 02:58 PM

I don't understand how it is a smoother takeoff without flaps? Since the shock absorption capabilities are very limited, it bounces up and down pretty badly as it's going down the runway and gets worse with speed. Since no flap takeoff takes an extra 5-10knots prior to lift off, isn't that just more bouncing and stress on the gear?

#12 Cabanaboy

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Posted 25 October 2012 - 03:27 PM

I never use flaps on takeoff, but usually takeoff from longer runways. I start to pull back lightly at 58-60 kts and she smoothly lifts. I usually gear up when i reach 500fpm. I use to only use one notch of flaps on landings but now use full flaps unless strong cross wind.

#13 N201MKTurbo

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Posted 25 October 2012 - 07:59 PM

With no flaps, you just put a little bit of back pressure when you hit about 50 knots or so (you can feel it) and the plane leaves the ground so smoothly the only wau you can tell you are airborn is the ride gets a little smoother.

201er, you need a smoother runway. :)
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#14 BigTex

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Posted 25 October 2012 - 08:40 PM

201er, you need a smoother runway. :)


Or new landing gear pucks :)

Gary Franks
Based at: KDTO, Denton Texas
1965, Mooney Mark 21 Model: M20C

#15 Hank

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Posted 25 October 2012 - 08:57 PM

Takeoff speed doesn't change with flaps unless you like to takeoff at stall speed. My Owners Manual says rotate at 65-75 mph, with flaps at Takeoff or as desired. Stall speed varies from 54-64 mph depending on weight, configuration, etc.

Flaps up, rotate ~70 mph, positive rate gear up, accelerate to Vx, climb over the trees, accelerate to Vy. Hold that to cruise altitude, CHT permitting. One change to make after throttle forward: gear up. Pitch for speed & trim as desired. Much less pitch change than taking off with flaps. Works well at my 3000' long home field.
--Hank
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#16 Antares

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Posted 29 October 2012 - 02:19 AM

I always use takeoff flaps as it seems to ensure the plane doesn't hop down the uneven runway as much. I also often use full aft elevator and add some right rudder to hold the centerline and keep the plane in ground effect on my takeoffs unless it's windy. I feel like it just gives me a little extra practice with the controls.

On takeoff, as I turn onto the runway, I have a thing I do that I call the "three 3s" where I have three groups of three items that I run through when I turn onto the runway. Sometimes you're lean, waiting for tower and you get cleared with "no delay" and have to rush. My 3s are this (67F): 1)[Verify trim,flaps fuel selector] 2)[fuel pump, lights, transponder] 3)[Prop, mixture, throttle]. The reason for the first set of three is that I've dropped people off with weather approaching and forgotten to reset my trim. I've also failed to engage the lever for the flaps (hydraulic) so when I put in my takeoff pumps I ended up doing a no-flap takeoff.

#17 jetdriven

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Posted 29 October 2012 - 02:49 AM

I like that checklist on the instrument panel for a quick turn.

Attached Files


Byron
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#18 Ned Gravel

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Posted 29 October 2012 - 05:40 AM

Two of the folks flying Mooney's at my home drome do not use takeoff flaps. It is not that I am smarter than the folks that wrote our "Owner's Manual" or that I will slavishly follow any now-proven-to-be-bad-advice from it, but on page 20 it says: "Check and following items before takeoff:" Number 6 on that list is: "Set wing flaps to take-off setting (see indicator)." My experience in both following that part of the takeoff checklist and not following it has provided me with sufficiently good reason to use them.

My friends who do not use take off flaps both have three bladed props and this may be why they can get the takeoff performance they want without the takeoff flaps (just me conjecturing here). They climb better than mine and I have flown with one of them in theirs (a now-sold 64 E model). In mine, I find that the aircraft gets airborne easier with the takeoff setting than without.

So I normally do use flaps for takeoff.
J.E.J. (Ned) Gravel, lucky steward of C-FSWR at CYRO (Rockcliffe), a '65 M20E (s/n 821)

#19 Stefanovm

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Posted 29 October 2012 - 09:35 AM

I use 1/2 flaps (my manual recommendation) most all the time. The only big difference I notice is lower nose angle. All the other reasons others give for using also make a slight difference. Added together, flaps seem to be the way I like to have the airplane feel. Otherwise, there does not seem to be a performance difference, except to 50' clearance, which seems faster in forward motion, not necesarily in time. I fly out of 2,500' grass with 50' obstacles at both ends, so when long runway using flaps has bcome a habit.

#20 Oscar Avalle

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Posted 29 October 2012 - 06:15 PM

I use take off flaps most of the time.
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