Custom flap handle

[Battson]

Battson

Thanks for the response. I can see by your response that I will have a lot of practicing ahead of me to get the timing down for a quick liftoff. I am curious about what kind of minimal distances you have found you need to lift off and clear a 50' obstacle consistently.
CJ

That all depends on weight.
As little as 250ft is possible at sea level with minimum weight aboard and almost no fuel.
At 2700lbs max all up T/O weight, then you need at least 600ft, at high density altitudes maybe 800ft or 900ft plus. DA makes a huge difference.

[JimParker256]

The aviation "rule of thumb" guidance states that for each +1000 feet above Sea Level (DA), the following impacts are observed:

• [*=1]Takeoff distance increases by 10% [*=1]Obstacle clearance distance (takeoff, climb to 50 ft AGL) increases by 15% [*=1]Fixed-pitch prop climb performance decreases by 7% [*=1]Constant-speed prop climb performance decreases by 6%

I find those guidelines to be incredibly helpful, but remember that it is like compound interest – meaning that at a DA of 6000 feet, your takeoff distance isn't 160% of your sea-level distance, but 177% (1.1 raised to the 6th power = 1.77). In the case of my O-200 powered 7ECA, my 600 fpm rate of climb at sea level becomes only 388 fpm at a DA of 6,000 feet (that's .93 ^ 6, or 64.7% of 600 fpm).

[rodsmith]

I have planned on a longer flap handle, have searched through the forum on what others have done. I prefer to modify mine like Jon did versus building a new one from scratch. Jon I believe I understand what you did but can not pull up your pictures. Any chance you could re post them when you get a chance?

[Archer39J]

Something to note for other Bravo kit builders. The fuel valve mount location seems to preclude the use of an extended flap handle.

Not sure if I'll even do anything here, need to see how the forces are in flight first.

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[rodsmith]

I put my fuel valve between my feet so not an issue for me.

[Archer39J]

Any chance you could re post them when you get a chance?

Just realized I could help, photobucket fix FTW!

These are photos of Battson's flap handle:

[rodsmith]

Thanks Archer !

[Battson]

One thing I have learnt recently about the long handle, is that with full flap and a tall man in the passenger seat, you can run out of stick travel at the extreme limits if they put their leg in the wrong place. Their leg gets trapped between the stick and the flap handle.
It only effects the long-legged passengers.
Pilots side, the flap is offset to allow room for the bellcrank etc, so the pilots leg does not cause the same problem.

[muleyman78]

HAs anyone thought about a block and tackle like system. It was a long hard day at work so my brain cant come up with wording but could a few pullys routed in series reduce the amount of effort needed to pull the handle? This pic is a quick google search but I hope you get where im going with this?

[PaulSA]

Unfortunately, TANSTAAFL.......

To get the 4x mechanical advantage (as in the diagram), you need to have a flap lever that moves 4 times the range. More realistically, you could have a 2x arrangement but I still can't see how you could get the necessary range of movement.

[Nev]

Is it possible to mount a small gas strut acting against the flap linkage to assist with the flap pull?

[Bdflies]

Nev, the resistance when pulling flaps, is the air load in flight. Any mechanism that applied constant force (like a pressurized strut) would force the flaps down on the ground and until the aircraft was going fast enough to force the flaps up.
If one wasn't able to pull flaps, even with an extended handle like Battson's, it would be fairly easy to employ a small linear actuator to elecrically power the flap system. Some don't care for electric flaps in STOL type airplanes (I fit in this category), but if that's what was needed, it wouldn't be hard.

Bill