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Flap position sensor mounting

tonyjohnson

Well Known Member
I spend all day today trying to figure out how to mount the ray allen pos-12 position sensor that I am using to tell the LED indicator on the panel what the flaps are doing.

After serveral attempts, I found the length of the arm, where it should mount on the bulkhead, etc. I then realized that the seat belt anchor points near the flap weldment woud interfere.

Has anyone installed the pos-12 in an 8? If so, please share how you did it. Pics would be greatly appreciated.

A sample installation is shown here:

http://www.aircraftextras.com/FPS-Plus-Mech.htm

Unfortunately the sample does not show an 8, with its seat belt anchor point next to the flap weldment.


Thanks,

Tony
 
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POS-12 in an 8

I'm at this point - anyone got any pics for an 8?

I think I know what I will do, but always nice to see what has been done!
 
I installed mine at the same point in my RV8- on the bulkhead the seat rests agains, up fairly high, close to the armrest. The seat belt anchor doesn't interfere. I'd take a picture, but the plane is at the painter for interior painting.
 
an additional idea

My sensor setup is almost identical to what Chris has; with one exception: Where the link attaches to the flap actuation arm; I used a small hose clamp with a bit of thin rubber (Old inner tube) under it to hold the fitting. This allowed me to adjust the position until I got the throw I wanted.

I also used a a small block of tapered wood with thru-machine screws as a mount instead of bending the aluminum - since I had a band saw handy it was faster and about the same weight.
 
Look out the canopy, instant flap position sensor. No parts to fab, adjust, or maintain.
I find that twisting my head around quickly to look at the TE of the wing gives me a little vertigo. Prob not a good thing when about to flare. And I do sometimes add flaps all the way down to touchdown.

Also easier when taxiing clear of the runway, switching to ground, shutting down the xpdr, landing lights, boost... to just glance at the indicator to know when the flaps are up.

Now to answer your question, I mounted mine about the same as those above and still works fine after flying 10 years as of June 6. I think I clamped the linkage horn to the cross bar too.
 
I would like to add another question to this thread. There is 3 different Ray Allen flap position sensors. one with .5" travel, a .7" travel and one with a 1.2" travel. For the -8 which one should I get? Thanks Lyle
 
Tony,
I sympathize with you. I too had many attempts at positioning the adel clamp and adjusting the threaded rod before I got just the right amount of position sensor linkage arm movement.

Here is my link with some installation pictures.

http://www.mykitlog.com/users/displ...rk&project=211&category=4841&log=99046&row=11

10 years later and your kitlog page just helped another RVer that needs pictures to understand some terms since I'm not an A&P. Thanks !!
 
I look out the canopy. I have spring loaded center switch switch and do a 2
count on down wind, 2 count on base, +2 count to full down on final. The
switch latches to up for flap retract and a limit switch shuts the motor off
if I forget to set it to middle.
 
I look out the canopy. I have spring loaded center switch switch and do a 2
count on down wind, 2 count on base, +2 count to full down on final. The
switch latches to up for flap retract and a limit switch shuts the motor off
if I forget to set it to middle.

I'm not installing it to know where the flaps are, I need it for the ON SPEED system.
 

Is it just me but the link opens the page but it doesn't load any pictures. Please let me know if it's just me so I can figure out why.

UPDATE: the link takes you to a page but then you have further click on the title so it shows the pictures. This link sends you directly to the pictures https://rv8haven.wordpress.com/2018/12/07/flap-position-sensor-4-8-hours/
 
POS-12 installed in RV-8 for flap position

I've just finished installing the Ray Allen POS-12 in my RV-8. Below is a link to a photo.
Similar to previous posts, I used two Adel clamps for extra rigidity and fabricated a small bar with multiple holes so I could use the hole that produced the proper amount of movement of the linkage. The link is an RC model control link with a 4-40 threaded rod and two forks, so the length is adjustable, and I had to cut it down to about 2" to get the right throw. I mounted the POS-12 on an angled piece of aluminum to align it with the linkage. The important thing is to avoid extending or retracting the sensor arm to its full stop, which will damage it.
I put mine on the starboard flap arm because my ELT antenna base is attached to that bulkhead on the port side. Orienting the Adel clamps toward the outside gives enough clearance to the seat belt attachment, barely.

The wiring will be connected to my G3X through a GEA 24 when my panel is upgraded later this year, so I can't now confirm that it works, but I foresee no problem.

https://photos.google.com/search/_tra_/photo/AF1QipNZ2SJTeEa126nu18fJToGTH3fulUuBQwtxaht2
 
Donaziza,
Let's try this.
https://photos.google.com/photo/AF1QipNZ2SJTeEa126nu18fJToGTH3fulUuBQwtxaht2

If that doesn't work, try this and remove the space before //
https: //photos.google.com/photo/AF1QipNZ2SJTeEa126nu18fJToGTH3fulUuBQwtxaht2

AF1QipNZ2SJTeEa126nu18fJToGTH3fulUuBQwtxaht2
 
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