How long do you wait to retract flaps on takeoff?

[ArtVandelay]

17 minutes ago, gsengle said:

 

Any flaps is drag. More lift is by definition drag.

 

But induced drag is not usually as big as factor as parasitic drag, with the flaps in full down position, that seems like that would create a lot of drag.

[gsengle]

Yes but any flaps creates drag and your fastest climb is no flaps at the proper speed.

Sent from my iPhone using Tapatalk

[BDPetersen]

When transitioning to the manual gear Mooney, I suggest the trainee use a 1-2-3 method, gear-prop-flaps. Once gear is up, hand goes to flap control. When flaps are selected up, hand to the prop control to back off rpm's a bit (2500). This triplet approach is to guard against those moments of self-congratulation after successfully wrestling with the Johnson bar causing an interruption in the flow of events and leaving the flaps down. In a routine departure profile, these 3 events occur fairly quickly. Throw in high gross weight, obstacles, or whatever, the process slows down to allow for acceleration and altitude.

[gsxrpilot]

It depends...

As I fly a manual gear Mooney, I usually go directly from Rotate to Gear-up.  

IF I used take-off flaps, I'll typically retract them once I'm as high as the surrounding obstacles such as tree tops or Control Tower.

[TWinter]

Usually after the gear..

 

 

-Tom

[Raptor05121]

3 hours ago, Hyett6420 said:

Not idiocy. Noise abatement. 

I wasn't directing that at you personally, and I understand that. I just see some guys pull power back for no reason. To me, I want as much distance between me and the ground, and touching the throttle is only going to increase the chance of something changing with the engine.

[Guest]

On August 14, 2013 at 9:46 AM, Marauder said:

On August 14, 2013 at 8:42 AM, DAVIDWH said:

Any one have any experience with this one? Not sure if this came from the poh or a blog, but I remember reading that "no flap take offs in long body Moonies increase the propensity for dragging the tail. Is this possible?

At the New Garden fly-in we had a long body there. That tail is a lot lower than I even imagined. I think 201er was talking to the owner about that possibility. It sure looks possible.

The tail on long bodies sits a lot lower than the others, it is further magnified by worn main gear shock discs.

Clarence

[Hank]

Oh, the joys of a shirt body!

I use Takeoff Flaps only when heavy. Full .rich, Full RPM, WOT! Zoom!! Rotate, confirm positive rate, gear up. If I used flaps, then Vlear if Obstacles, Flaps Up. WOT/2700 to altitude, leaning to Target EGT when I remember. I also climb at Vy when temps allow, 100 mph - Altitude.

There's no point in climbing slowly, it only raises engine temps by reducing airflow, and keeps you in the climb for a longer time.

[jlunseth]

I am the same as Ward, but don't wait for 400 to raise the flaps.  The aircraft picks up a fair amount of speed when the flaps are raised, and I convert that speed into climb rate by pitching up, increasing climb rate.  I target for an initial climb speed of 85 knots to get as quickly as possible to 1000 AGL, and the quicker I can get the flaps up the quicker I get to 1000.  1000 is my minimum altitude for a turn back to the airport in the event of engine failure.  My choice of 85 is a little arbitrary.  It comes from an article in AOPA Magazine about the miracle turn, where the authors found that a climb at best glide was the fastest way to get to turnback altitude.  My best glide is 81-85 depending on loading.  

[kpaul]

15 hours ago, jlunseth said:

My choice of 85 is a little arbitrary.  It comes from an article in AOPA Magazine about the miracle turn, where the authors found that a climb at best glide was the fastest way to get to turnback altitude.  My best glide is 81-85 depending on loading.  

So I am curious, have you practiced climbing at 85, simulating a failed engine and then trying to maintain that 85 in a 180 degree turn?  That will require a very aggressive pitch down to keep from stalling.  There are a couple of schools of thought about turn-backs. Most in the GA world will tell you to not do it and pick a spot within 30 degrees of your nose track.  We regularly practice 180 turnbacks in the PC-12s I fly.  They can be accomplished all day long at 800AGL. Having AOA is a huge benefit.  Now since I have not had my Mooney all that long and have not had the opportunity to practice turn-backs I will relinquish to straight ahead until I have the experience and more data on the amount of altitude I would lose in the turn which would then drive my no lower than turn-back altitude.

[jetdriven]

21 hours ago, BDPetersen said:

When transitioning to the manual gear Mooney, I suggest the trainee use a 1-2-3 method, gear-prop-flaps. Once gear is up, hand goes to flap control. When flaps are selected up, hand to the prop control to back off rpm's a bit (2500). This triplet approach is to guard against those moments of self-congratulation after successfully wrestling with the Johnson bar causing an interruption in the flow of events and leaving the flaps down. In a routine departure profile, these 3 events occur fairly quickly. Throw in high gross weight, obstacles, or whatever, the process slows down to allow for acceleration and altitude.

Do you also pull the prop back in a 182 or a M20S eagle? Those are only 2400 RPM on takeoff.. Or what about a 172? Back it off a little as well?

 

[Shadrach]

For me, raising flaps is not about altitude or obstacles or whether the gear is up or down. Certainly "positive rate" is a must!   For me, raising flaps is about airspeed.  That speed is somewhere around 85-90mph.   I like the way the airplane comes off the runway with flaps. I just think the wing does better at low speeds with the boards out a bit. I also think it improves  slow speed forward visibility more than many realize.   Deploying flaps increases the angle of incidence giving you greater AOA for a given pitch yielding better forward visibility. Once the airspeed is above 90mph the flaps can be retracted and the plane will climb better sans flaps and with great forward visibility. 

Folks should be familiar with climbing with flaps in all positions. My F actually climbs well with full flaps if I'm not too heavy. It feels bizarre because the pitch is flat but it climbs out at a steep angle. 

[PTK]

Pos ROC, Vx clear any obstacles (real or imaginary!) gear up, nose over to Vy, Flaps up, haul ass!

[Hank]

1 hour ago, PTK said:

Pos ROC, Vx clear any obstacles (real or imaginary!) gear up, nose over to Vy, Flaps up, haul ass!

Positive rate, gear up, Vx to clear obstacles, raise flaps if used, Vy to altitude. Simple, easy, effective.

[Shadrach]

On March 31, 2016 at 6:19 PM, Hyett6420 said:

Not idiocy. Noise abatement. 

Those who think a 200RPM reduction in RPM does anything other than please bureaucrats and city councils are kidding themselves. Oh wait I forgot, it does reduce ROC by about 15%! 

[N201MKTurbo]

Back when I flew planes that needed takeoff flaps, I would put them up as soon as I could get away with it. the plane will sink a bit on flap retraction especially if done quickly. So the only criteria was that you had enough altitude that you wouldn't hit anything from the sink. On a big flat long runway 50 feet is plenty. If there are obstacles, you have to wait till there is no question that you will clear the obstacles before retracting the flaps.  

I would always advocate retracting the flaps before the gear so if you did sink back to the runway you still have rollers.

[laytonl]

On August 9, 2013 at 6:27 PM, PTK said:

I consider a positive rate of climb (PRoC) to be the absolute determining factor and a MUST before flap retraction.

 

PRoC should be in your poll Mike. You don't you even mention it?!

 

I retract flaps once I have a PRoC and clear of any obstacles.

 

PRoc, gear up, flaps up.

This.  Lee

[jlunseth]

20 hours ago, kpaul said:

So I am curious, have you practiced climbing at 85, simulating a failed engine and then trying to maintain that 85 in a 180 degree turn?  That will require a very aggressive pitch down to keep from stalling.  There are a couple of schools of thought about turn-backs. Most in the GA world will tell you to not do it and pick a spot within 30 degrees of your nose track.  We regularly practice 180 turnbacks in the PC-12s I fly.  They can be accomplished all day long at 800AGL. Having AOA is a huge benefit.  Now since I have not had my Mooney all that long and have not had the opportunity to practice turn-backs I will relinquish to straight ahead until I have the experience and more data on the amount of altitude I would lose in the turn which would then drive my no lower than turn-back altitude.

Yes but not enough.  First, you don't do this practice during a takeoff, you go to altitude and do it.  Give yourself at least 3,000 AGL.  It does take an aggressive nose down move.  I think the main value of practicing is to instill that move into muscle memory, because there is going to be no time for indecision and airspeed is going to be everything.  I don't have the courage to try nose down and turn at the same time, BTW.  I nose down, and give the aircraft a chance to actually nose over stright ahead before I make the turn.  You have to watch the turn and not be overly aggressive, the plane stalls at 90 in a 60 degree turn and I have done that - stalled the plane at 90 in a 60 degree turn - practicing steep spirals, so I will go to 45 but not more.  And the turn is a 270, not a 180, because you have turned left or right of the runway and need to get back to it.  

It is a very useful exercise, because when you do it, you know to a certainty that below a given altitude for your aircraft, there is no chance of a turnback.

 

[Shadrach]

20 hours ago, kpaul said:

So I am curious, have you practiced climbing at 85, simulating a failed engine and then trying to maintain that 85 in a 180 degree turn?  That will require a very aggressive pitch down to keep from stalling.  There are a couple of schools of thought about turn-backs. Most in the GA world will tell you to not do it and pick a spot within 30 degrees of your nose track.  We regularly practice 180 turnbacks in the PC-12s I fly.  They can be accomplished all day long at 800AGL. Having AOA is a huge benefit.  Now since I have not had my Mooney all that long and have not had the opportunity to practice turn-backs I will relinquish to straight ahead until I have the experience and more data on the amount of altitude I would lose in the turn which would then drive my no lower than turn-back altitude.

I shoot for 120Mias in the climb. 180s can be performed in under 500'.