When retract gear at take off at short fields

[jaylw314]

Didn't someone in a previous thread post something by a test pilot (Kromer?) noting at low speeds, the drag from full flaps was actually greater than the drag from the gear?  Hence the instructions in most Mooney POH's to retract flaps to takeoff position first, then gear up, then retract the remaining flaps.

[midlifeflyer]

12 hours ago, Shadrach said:

94mph or 82kts is Vx in my F.  Not a problem to retract at that speed but noticeably different from retracting at say positive rate. I think the difficulty in retracting the gear at higher speeds is overstated though it does get heavy as you approach V_LO

No question. 

[skydvrboy]

9 hours ago, carusoam said:

To get POH performance, you have to follow POH procedure...

My POH is pretty vague.  It says "take off configuration: gear down, 15 degrees flaps" and "climb configuration: gear up, flaps up."  I guess that means after takeoff and before climb I have to get the gear up and the flaps up. That makes for a very busy transition period! 

[Bob_Belville]

1 hour ago, skydvrboy said:

My POH is pretty vague.  It says "take off configuration: gear down, 15 degrees flaps" and "climb configuration: gear up, flaps up."  I guess that means after takeoff and before climb I have to get the gear up and the flaps up. That makes for a very busy transition period! 

My old E model has very low max speeds for gear (104 kias) and flaps (87 kias). Raising the gear has little effect on the Vx-Vy climb performance or pitch so I get gear stowed asap. (Moving the JBar does take the pilot's hand off the throttle which should be a consideration.) Vy is higher than Vfe so I have to raise the flaps when airspeed gets to about Vx or a few hundred feet.

[Ibra]

Assuming you have lot of power to reach Vx or Vy with gear down very soon in ground effect, once in climb the gear down does create drag without any impact on your lift, that actually help acheiving a steep climb angle, if you don't follow the intuition ask why a STOL aircraft climb on full power and full flaps?

In practice, in a heavy touring aircraft (full of fuel & pax) what kills your short field takeoff petformance is the ground roll to liftoff, whatever you do in the climb seems to have less chances of fixing anything, I would just consistently learn to go with flaps at takeoff position, accelerate in ground effect and climb at Vy then retract both takeoff flaps/gear once clear of obstacles and worst case I will just aim for top of obstacles with lot of speed excess while resisting temptation to pull up anything (stick, gear, flaps)

This technique works for me, it is not the best, but having done this many times I know exactly how much speed margins I have for various short runways (as it is hard to judge your height margins when flying at Vx) I visited as well if I can comfortably make it somewhere else before trying, and even if I am wrong I can still pull the stick and I may get away with it...

[Hank]

Let's see what the Owners Manual says. Here is mine:

Takeoff, gear up, raise flaps when clear of obstacles. What does yours say? I follow mine.

[jlunseth]

I am going to respectfully disagree on the advice to raise the gear quickly in a short field.  In my 231, raising the gear creates a distinct nose-up. It requires quite a bit of forward pressure to keep the aircraft in a normal attitude. In a true short field, again in my aircraft, the airspeed for the Vx climb is only 15 kts. above stall.  A nose up at low altitude close to stall is not a good idea.  I leave the gear down to climb to obstacle height.  I am not where I can look at the POH but I am fairly sure that is what it calls out for the 231.

Different models act differently. But that is how I do it.  

[skykrawler]

7 hours ago, skydvrboy said:

My POH is pretty vague.  It says "take off configuration: gear down, 15 degrees flaps" and "climb configuration: gear up, flaps up."  I guess that means after takeoff and before climb I have to get the gear up and the flaps up. That makes for a very busy transition period! 

Uh....I think once the gear and flaps are retracted you are in the climb configuration.

My obstacle clearance takeoff experience is when I rotate I have to focus carefully to keep the airspeed from going above Vx at a very high pitch attitude.  No messing with the gear then. After clearance height is achieved nose down gear up.  I believe that at Vx speed the gear drag is less important than getting the thrust vector pointed up.