Flap Position Sensor Install - 9A

[skelrad]

I'm working my way through wiring. I have my wings sitting in the cradle, but won't be doing the initial fit for a while just because I'm not ready to do the shop space juggle yet. I have the Ray Allen POS-12 sensor that I'll be using as a flap position sensor, and in order to mount it at the right angle I need to have at least a general idea of what the flap arm travel will be. I can't find a callout in the plans that indicates what the total amount of travel will be. If I run the motor to each stop, can I assume that's close to what the real world travel is, or is that way more movement than will occur when the flaps are connected?

 

[ClayR_9A]

Do you really want or need the flap position sensor? A quick glance over will confirm visually. Personally, my flaps are only either full up or full down. I push the switch up or down until I hear the motor sound change and I know it has reached the limit.

 

[MacCool]

Do you really want or need the flap position sensor? A quick glance over will confirm visually. Personally, my flaps are only either full up or full down. I push the switch up or down until I hear the motor sound change and I know it has reached the limit.

My EFIS, in order to apply the full range of AoA functionality and display it, requires knowledge of flap position, at least full up vs full down. My airplane was build with the POS-12 and it accomplishes that just fine.

If I was OP, I'd be building the flaps around the Showplanes FPS system rather than the Ray Allen POS 12. I don't use flaps much, but on a touch-and-go or go-around, I would prefer to go from down to full-up with one switch push rather than holding the rocker switch for the entire range of flap travel. IMHO, YMMV, etc etc.

 

[skelrad]

My EFIS, in order to apply the full range of AoA functionality and display it, requires knowledge of flap position, at least full up vs full down. My airplane was build with the POS-12 and it accomplishes that just fine.

If I was OP, I'd be building the flaps around the Showplanes FPS system rather than the Ray Allen POS 12. I don't use flaps much, but on a touch-and-go or go-around, I would prefer to go from down to full-up with one switch push rather than holding the rocker switch for the entire range of flap travel. IMHO, YMMV, etc etc.

I'm using AFS' ACM, which handles all of this. It requires the use of the POS 12 to do that though. That's why I'm using it vs another system.

 

[bruceh]

Here is what I came up with and has been working great for over 10 years.

Full down flaps. Motor jackscrew is fully retracted. Sensor arm fully in.

Full up flaps. Motor jackscrew is fully extended. Sensor arm fully out.

The Ray Allen POS-12 has a throw of just over 1". Putting the sensor in line with the arm required building a little bracket at the same angle and flush riveting it to the aft flap motor cover. An Adel clamp just at the end of the weldment strap that goes around the flap tube gives the 1" movement range. The threaded rod arm with the clevises is from a hobby shop.

 

[GeoffP]

I followed Bruce's concept. It just takes a little bit of tweaking the Adel clamp position on the flap tube to ensure the throw is within the limits for the POS-12. I had the flap motor installed, and I just drove the motor to the limits without having the rod to the POS-12 connected, and adjusted as needed.

 

[ge9a]

I followed Bruce's concept. It just takes a little bit of tweaking the Adel clamp position on the flap tube to ensure the throw is within the limits for the POS-12. I had the flap motor installed, and I just drove the motor to the limits without having the rod to the POS-12 connected, and adjusted as needed.

Yep, same as mine. So far (~140 hrs and lots of landings) it has worked well.

 

[Gnvflyer]

I did mine the same as Bruce above, but find now that I'm flying, I rarely look at the indicator. It's easier to just look at the left flap out the window.

If I were to build another RV, I wouldn't bother with it.

 

[cajunwings]

This can be done a number of ways. On the last 3 planes I located the transmitter on the rear side of the 705 seat back bulkhead above the right flap pushrod. Be careful the transmitter doesn’t bottom out at full travel. Popsicle stick was a temporary link to work out the length.