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Momentary or Position-based Flap control?

N890GF

N890GF

Well Known Member
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I recently completed phase 1 on my -7 and used Momentary control the whole time. I found myself really using only two positions - mid flap on base and full flap on short final. Nothing really in between. My VPX has position based flap control, so I switched it over and set those two positions. I haven't flown with it yet, but curious what others have done? Pros and Cons for each would be interesting too
 
I had the same situation. Finished my Phase one with no position points in my flap control. Latter I added three positions to make them more like the Cherokee that I had been flying for 20 + years. It is nice to have the flexibility to be able to configure it how you like it.

I prefer the ability to land with different settings based on wind conditions.
 
Garmin is similar to VPX in that it allows you to set way to many flap positions. After playing with it for a while with switch bumps for every 10 degrees, I got tired of hitting that switch so much and settled on just two positions that match the Vfe limits for the plane. 1 bump = 20 degrees, deployable below 93 KIAS, 2 bumps = full flaps below 85 KIAS.

I normally hit the first notch abeam the touchdown point at about 90 knots and the 2nd notch turning final.

edit- I just remembered that when I set this up I padded the numbers a little. Per Vans 20 degrees = 110 mph/95 kts. more than 20 degrees = 100 mph/87 kts
 
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I use three set positions on my 8 (10, 20 and 40) controlled via a momentary thumb switch on my stick grip. One tap after slowing to 100 kts abeam the numbers for 10 deg, another tap on base when below 87 kts for 20 and a third tap on final for 40 unless the winds dictate otherwise. After landing its one tap up to raise them unless I'm going to park the airplane. Then they stay down. I like the consistency of the set positions.
 
I imagine it is airframe and prop dependent but on mine I don’t find settings below 30 degrees make much difference and settings above 30 degrees just add drag. I tend to use all or nothing.
 
I prefer manual switch control, the ability to adjust up or down as needed.
At one point I installed a switch so up was able to be selected without holding the switch, after retracting the flaps by mistake once I removed it.
 
Lkitson said:
I use three set positions on my 8 (10, 20 and 40) controlled via a momentary thumb switch on my stick grip. One tap after slowing to 100 kts abeam the numbers for 10 deg, another tap on base when below 87 kts for 20 and a third tap on final for 40 unless the winds dictate otherwise. After landing its one tap up to raise them unless I'm going to park the airplane. Then they stay down. I like the consistency of the set positions.
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Thats obviously working for you, but the 1st 10 degrees at 100kts is a little hot according to the book. It's only 5 kts or so, probably not worth quibbling over, but just so people know...
 
Mikeyb said:
I imagine it is airframe and prop dependent but on mine I don’t find settings below 30 degrees make much difference and settings above 30 degrees just add drag. I tend to use all or nothing.
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The big CS prop does a good job on slowing down the RV. My FP prop RV8 requires more finessing using the flap at pattern altitude in order to slow down to a desired touchdown speed.
 
I don;t use any smart flap controls on our planes - just a momentary switch position for down and a latching “up” position so I can hit “up:” and forget about them, as they stow. I am of the school that I drop all the flaps abeam the numbers (in and RV) and then just fly the airplane to touchdown - less to do. I have the capability to put them at any intermediate position I want for extreme wind conditions, but rarely use anythign less than full. I certainly don’t fly the -15 with the barn-door flaps that way of course!
 
Desert Rat said:
Thats obviously working for you, but the 1st 10 degrees at 100kts is a little hot according to the book. It's only 5 kts or so, probably not worth quibbling over, but just so people know...
Click to expand...
Where do you find published numbers for 10 degrees? The Van's build manual only lists 110 mph for 20 deg and 100 mph for 40 deg.
 
Desert Rat said:
VPX and Garmin. Probably others as well.
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I have the Showplanes system, which is pretty foolproof, but it doesn't allow customization (I wish it had only 2 positions, not 3) and it doesn't know about airspeed.

Lkitson said:
Where do you find published numbers for 10 degrees? The Van's build manual only lists 110 mph for 20 deg and 100 mph for 40 deg.
Click to expand...

I've always interpreted the partial-flap limitation as "up to 20 degrees below 110 mph" - so 10 degrees would be covered by that.
 
mburch said:
I've always interpreted the partial-flap limitation as "up to 20 degrees below 110 mph" - so 10 degrees would be covered by that.
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Makes sense. But 100 knots for 10 seems to be the excepted number for a lot of pilots.
 
Ironflight said:
I don;t use any smart flap controls on our planes - just a momentary switch position for down and a latching “up” position so I can hit “up:” and forget about them, as they stow. I am of the school that I drop all the flaps abeam the numbers (in and RV) and then just fly the airplane to touchdown - less to do. I have the capability to put them at any intermediate position I want for extreme wind conditions, but rarely use anythign less than full. I certainly don’t fly the -15 with the barn-door flaps that way of course!
Click to expand...
Must be nice to have the pattern all to yourself!
 
I installed a GAD 27. Not debating one system vs another but I kept the avionics all in a single family.

Probably true with other systems as well, but an option (straight from the Garmin G3X manual) =

If the flap switch is held longer than 1 second, the flaps will run in the specified direction until the flap switch is released or the flap limit switch is triggered. This method of manually moving the flaps is not
affected by user-defined airspeed limits. This behavior can also be used in conjunction with a non-
momentary switch in order to fully retract the flaps with a single pilot action

Something for consideration if you didn't know.
 
Ironflight said:
I don;t use any smart flap controls on our planes - just a momentary switch position for down and a latching “up” position so I can hit “up:” and forget about them, as they stow. I am of the school that I drop all the flaps abeam the numbers (in and RV) and then just fly the airplane to touchdown - less to do. I have the capability to put them at any intermediate position I want for extreme wind conditions, but rarely use anythign less than full. I certainly don’t fly the -15 with the barn-door flaps that way of course!
Click to expand...
Same here, though I rarely use 40* on the 6. We have a lot of rotor type turbulence at our field and learned early on that 30* seemed less reactive to those than 40.
 
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