When do you retract flaps to 0 degrees?

[Batjac]

Looking at my CLTS AOI, it says to go from +15° to 0° at a minimum of 150 feet if in a large pattern, and at 1,000 feet in a small pattern.  As a rule, I have been going to 0° around 600AGL.  When I was doing my transition training, my instructor had me do it at around the 150 foot mark, but I like having a little more altitude before raising the flaps and getting that initial drop in lift.  When do Y’all go to 0 degrees?

 

Mark

[GrassStripFlyBoy]

For me this is not a fixed decision based solely on AGL, it varies on what level of climb performance you need to achieve.  When solo at a large open airport I'll take off with 0 or even -6, as I'm still climbing at great rates and if anything happens I can still make the field in return.  If the departure area is not suited for straight ahead emergency landing zones, then I'll leave flaps longer, perhaps the 500' mark?  I'd not want to give up any climb performance in areas where popping the chute is your plan A emergency procedure.

[Skunkworks85]

Climb out at Vx at 15° until 800' AGL, pitch for Vy and retract flaps to 0°

[FlyingMonkey]

Usually 500ft, sometimes more or less depending on conditions.  I like to keep the flaps down until I could turn around and land without touching anything.  In an emergency return you don't want to be fiddling with flaps.  Once at 0° I immediately go to -6° once speed is above 70kts, to minimize drag and get best climb.

[EricB]

I'd agree that there is little to no reason to pull in the flaps at 150 ft.  What are you needing to accomplish with that?  Like several said, I use a situation dependent transition point.  If I'm climbing at 800 fpm and speed is good, sacrificing that for a 500 fpm climb isn't a sacrifice at all.  That said, I only use a flaps 15 takeoff when it is called for by local conditions.  Crosswind control is always better at flaps zero.  

[Tom Baker]

My normal, and this is what was recommended when I got started with CT's back in 2007 is, 400 feet AGL to 0°, and 800 AGL to -6°. With experience, by myself, and with landing options I have reduced flaps much sooner, but that is not my norm.

[Anticept]

Flaps for me go up with positive rate of climb and 50 feet off the runway, done by eye and not reading an altimeter.

The drop isn't as much as you would think., it's certainly not enough to negate the climb rate of a CT.

If i were operating at a 10,000 ft airport that's a different story.

I also don't keep the pitch high, the nose drops after it leaves the runway to get speed (and options to abort). So once I start the actual climbout it rockets to 800+ feet a minute.

Short fields keep the flaps in until clear of obstacle + 100 feet if applicable.

[FlyingMonkey]

21 hours ago, EricB said:

I'd agree that there is little to no reason to pull in the flaps at 150 ft.  What are you needing to accomplish with that?  Like several said, I use a situation dependent transition point.  If I'm climbing at 800 fpm and speed is good, sacrificing that for a 500 fpm climb isn't a sacrifice at all.  That said, I only use a flaps 15 takeoff when it is called for by local conditions.  Crosswind control is always better at flaps zero.  

Technically crosswind control may be better at 0° yes, but...

1) Takeoff roll is *significantly* increased.

2) Rotation speed (and thus energy) is also significantly increased.  If you blow a tire or have something else happen right before rotation, you have a lot more energy to dissipate. 

YMMV, but I always use 15° flaps for takeoff unless there's a compelling reason not to.  Crosswind control at that setting is fine up to 15kt or more direct crosswind, and with a crosswind it's better to get off the ground ASAP and deal with the winds in the air than fight them on the runway.  Again, just IMO.

[Eddie Cesnalis]

My normal takeoffs have evolved.  At my home 3,000' field I takeoff with 15 as soon as I have flying speed with an elevated nosewheel then lower it to remain in ground effect.  I accelerate in ground effect and begin my climb when I hit 80kts and then zoom almost to pattern altitude.  It's very fun and very positive and the point where I begin to climb I could still abort.  ( I might be off the end of the runway and into the sand dune but that wouldn't be bad.

The zoom climb I get at 80kts is fun for an old man.  Useually I retract and quickly go to reflex ultimately my climb speed depends.  

[Anticept]

10 hours ago, FlyingMonkey said:

Technically crosswind control may be better at 0° yes, but...

1) Takeoff roll is *significantly* increased.

2) Rotation speed (and thus energy) is also significantly increased.  If you blow a tire or have something else happen right before rotation, you have a lot more energy to dissipate. 

YMMV, but I always use 15° flaps for takeoff unless there's a compelling reason not to.  Crosswind control at that setting is fine up to 15kt or more direct crosswind, and with a crosswind it's better to get off the ground ASAP and deal with the winds in the air than fight them on the runway.  Again, just IMO.

I want to note this is aircraft dependent. Some have a longer roll, some are shorter. I haven't tested a CT but I don't think it will make much of a difference.

While flaps are draggy, a significant amount of that drag will be offset due to ground effect even on the roll.

[FlyingMonkey]

11 hours ago, Anticept said:

I want to note this is aircraft dependent. Some have a longer roll, some are shorter. I haven't tested a CT but I don't think it will make much of a difference.

I totally agree, I was speaking exclusively to my experience with a CT.