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Permalink Reply by Bob Simmons on Thursday

Flap position senders typically vary a voltage signal to indicate position. I'm not familiar with this flap motor, but assuming that's the case, anything that displays voltage will work, even a digital voltmeter display. That's very simplistic (you'd have to correlate numbers to flap position), but your comment on EFIS space sounds like you want things very basic. That would probably take up more room than an EFIS depiction, but I suppose that may depend on what EFIS you have. There are numerous instruments designed to display flap position, but they'd take up even more room.

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Permalink Reply by Bob Simmons on Thursday

Assuming this is a typical position sensor, it will have a group of adjustable resistors (potentiometers), typically 1 kΩ, 5 kΩ, 10 kΩ, and 20 kΩ. A set voltage is applied for all, but only one resistor at a time is in use. The flap position determines which one that is. So, you'll get different voltage outputs that represent different flap positions, and the indicator in your cockpit will display the results accordingly. If you stay very simple with something like a voltage readout, it will be up to you to determine what voltage indication represents what flap position. You can tinker with the potentiometers to tailor the results. You can obviously get indicators that will translate the various voltages to flap readings, but those will usually take up more space, and it sounds like you're against that.

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Permalink Reply by John Austin on Thursday

I've had a flap position indicator for years in my STOL 750.  It takes exactly 4 seconds for full flap travel, and all I ever use is none, half, or full flaps. Sooo - hit the flap switch and count "One thousand and one, one thousand and two" and you're at half flaps from either full up or full down! 

Thankfully, the "computer" for my system has not required re-calibration ... so far!  :)))

John 

N750A

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Permalink Reply by Bob Simmons on Thursday

I'm pretty much of the same mindset, John. I was thinking just look out the window. But he wants an indicator, so I offered what help I could.

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Permalink Reply by Frank Stutzman on Friday

This topic came up recently on the facebook Super Duty builders group.

I would normally be a 'look out the window" kinda guy.  However, all of the good angle of attack indicators take flap position into consideration when doing their calculation.  As I am planning on having an AoA, I'm pretty interested in having a sensor built into the motor.  I just sent a note to Roger to see if this new motor can be retro-fit into the SD.

Sorry, I guess this response doesn't help the original poster at all.

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Permalink Reply by John Austin on Friday

Frank's comment brings up an interesting topic.  So as not to creep the thread further from David's original question, I'm starting a new topic - AOA with Wing Slats? - in the Open Forum.

John

N750A

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