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Flaps Positioning System for RV-7 -- full extension?

Hi RV-7 gurus,

I am trying to upgrade my RV-7 to have a flaps controller so that I can have three-position auto-extend and no longer have to look as long out the canopy while holding the switch. I've narrowed the choices down to the one from Vans and the one from TCW:

http://www.vansaircraft.com/cgi-bin/store.cgi?ident=1434197501-130-3&browse=electrical&product=fps

http://www.tcwtech.com/ifc_intelligent_flap_controller.html

My inclination is to go with the one from Vans as it's slightly less expensive and factory endorsed, but my A&P was saying something about the Vans FPS not being able to fully extend on an RV-7. I'd like to get full 40 degrees flaps. The Vans web page also says "(degrees of travel varies with aircraft type)" which has me a little worried.

Can anyone else with experience with the Vans FPS on an RV-7 confirm or deny whether full extension is possible with this controller. Vans support staff is unavailable due to Oshkosh and I'm hoping to order this today.

Thanks in advance,
G
 
I considered installation of a sensor and purchased one from Ray Allen, along with running wires but after running the flaps up and down a few times, decided a 2 count for 10, 4 count for 20 and 8 count for full flaps works just fine.
 
I use the Vans FPS version on the RV7A and get slightly more than 40 degrees (full travel of the flaps). It may depend on how it's adjusted.

Bevan
 
I've done a deep dive on flap positioning systems and not been totally satisfied with any of the products.

So what's an old engineer going to do? Yup, I designed my own. It works in parallel with a manual system, so is more fail-safe.

I programmed my Falcon-AVR controller for this (search the forums more more details). Since I adjust both trim and flaps together, I found that only two preset positions make sense: take-off preset and landing preset. In between, I use manual control.

Take-off preset allows one-button push in a go around, and landing preset does the same, but for landing.

Here's the issue: these presets only work well at one CG position (solo flight). With a pax in the back seat, manual trim adjustments must be made. I could probably use a switch to select a mode for this, but that's not user friendly. A side by side would work better.

One more thing. I have found that full nose up trim in the landing configuration gives me exactly the short final approach speed I need for landing. This can be achieved with careful rigging of the trim tab, or in my case, dumb luck.

V
 
I decided to go with manual flaps on my -7, they work great, simple, light and fast. I used a -6 weldment and modified cabin floor to accept the anchor arm.
 
I, like Vern, was not happy with what's available so I also built my own programmable flap controller. I wanted a very simple version that with a single push of a button would deploy the flaps to a preprogrammed position. It can be set from one to three programmed positions the same way you program your car radio. Move the flaps to the desired position and use the memory preset. No counting, no holding buttons down and looking over my shoulder. I wanted a simple way to deploy flap so I could focus on flying the plane. It's capable of up to 10 amps of current. I have 4 lighted push buttons labeled UP, 10°, 20° and 30 °. They could be any degree you desire. I simply push whatever position I want and the flaps go there. The LED in the button is on solid for whatever position you are in. When I push a desired setting that button flashes while the flaps are moving and it goes solid when it reaches the programmed position and they stop. It works with any 12v actuator and the Ray Allen position sensor. Or actuators with built in position sensors. To get 40° of flaps will depend on the actuator and how it's mounted. I also have a manual backup in case of complete microprocessor failure.

It's been working great now for countless hours of flying.
 
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I considered installation of a sensor and purchased one from Ray Allen, along with running wires but after running the flaps up and down a few times, decided a 2 count for 10, 4 count for 20 and 8 count for full flaps works just fine.
My method too. Simple & reliable.
 
Count for down.

I considered installation of a sensor and purchased one from Ray Allen, along with running wires but after running the flaps up and down a few times, decided a 2 count for 10, 4 count for 20 and 8 count for full flaps works just fine.

My method too. Simple & reliable.

+2 and have a mark inside the left aileron to keep my brain tuned. I hardly use the marks now @40 hrs. This is the way Mike taught. Seems to be working for me.

That said, the automated landing trim setting sounds interesting.
 
Flap Position system for RV-7

Hi there
I have been using the Van's system for 10 years and am quite satisfied. It takes a little finessing to get the travel just right but once it's set it works great. Follow the instructions and make sure there is no binding of the sensing rod. I get the full 40 degrees with 3 clicks on the flap switch.

Dave RV-7
C-GCPD
 
I can't remember which one I have but I purchased a positioning system 10 years ago and use it. The fact is that there is a bit of flexibility because when you install it there is a notched rod that actuates the microswitches and you can position it on the flap actuator pushrod to give you some adjustability.

I had to spend a great deal of time finessing it to give me the results I wanted. One thing not already mentioned is to think carefully about how much "full flaps" you want. Yes the factory setting is 40 degrees. This is also extremely close to the flap coming out from under the upper wing skin. I don't think I could tell much of a difference in landing behavior between 40 degrees vs 37 or 38 degrees, but it allows more overlap to help assure that inadvertent popping out of the flap doesn't occur. If you don't notice it and retract the flaps it will be a very bad day.
 
Let me clarify. My controller positions both flaps and trim simultaneously, greatly reducing workload, especially in the go-around. I fully retained the manual position system for normal flaps-only positioning.

I put the automatic system because thingshappen fast in the Rocket.
 
I always scratch my head about these discussions. Like a couple others here I just count. One and two and three abeam the numbers, one and two and three going into the base leg and run it untill it churns on final. Simple, no adjusting, nothing to fail etc. Everything on every landing is infinitely variable and you have to adjust. Thinking that flap positions have to be perfectly accurate and automatic just doesn?t make a lot of sense to me, but different strokes.
 
Thanks all for the input!

I ended up getting the Vans Flaps Positioning Controller. Install looks good on the ground and I will try it out in the air once I'm flying her again.

FYI, there are a few reasons I went for a more automated setup:

- Avoid running the motor up against the stop -- my doing so repeatedly made my motor wear to the point that I've had to upgrade to a 7.5 A fuse from a 5 A fuse.

- Easier flap retraction on a go-around, when the situation is already stressful.

- Overall ergonomics, even when extending.

I might feel differently regarding the above if I had more experience/time on the airplane (like many of you!). But at this point, I want to reduce as much cognitive load as possible and be safe. I'm sure all of this will become second nature after I have more experience and build up my skills. :)

Best,
G
 
I, like Vern, was not happy with what's available so I also built my own programmable flap controller. I wanted a very simple version that with a single push of a button would deploy the flaps to a preprogrammed position. It can be set from one to three programmed positions the same way you program your car radio. Move the flaps to the desired position and use the memory preset. No counting, no holding buttons down and looking over my shoulder. I wanted a simple way to deploy flap so I could focus on flying the plane. It's capable of up to 10 amps of current. I have 4 lighted push buttons labeled UP, 10°, 20° and 30 °. They could be any degree you desire. I simply push whatever position I want and the flaps go there. The LED in the button is on solid for whatever position you are in. When I push a desired setting that button flashes while the flaps are moving and it goes solid when it reaches the programmed position and they stop. It works with any 12v actuator and the Ray Allen position sensor. Or actuators with built in position sensors. To get 40° of flaps will depend on the actuator and how it's mounted. I also have a manual backup in case of complete microprocessor failure.

It's been working great now for countless hours of flying.

Just saw this post from a while back. Are you still happy with your design? Would you be willing to share design details?
 
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