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Flap position sensor installation

A web search of "Vans Flap position sensor installation," and you'll find lots of help.
 
The MK-1 Eyeball is a great flap position sensor in the RV9. Requires no power, and the only maintenance is safety glasses in the shop and a once-a-year visit to the Optometrist.
 
I have the FPS+Plus and love it. It automatically set my trim and I have the option of a manual switch.
 
I have the FPS (before trim was available) and love it. One push of the momentary toggle switch advances the flaps to the next "notch". Each amount of flap deployment is the same every time. Toggle switch up brings them all the way up (or I can partially raise them by returning the switch to mid position). Keeps my eyes looking forward. I prefer to not have to turn my head 90+ watching the flaps deploy. I can hear and feel them moving. That's enough for me. Not much trim adjustment necessary.

Bevan
 
+1

The MK-1 Eyeball is a great flap position sensor in the RV9. Requires no power, and the only maintenance is safety glasses in the shop and a once-a-year visit to the Optometrist.


You can spend years adding useless gadgets to your airplane or you can build it light and simple and spend that time flying. Your choice.
 
The MK-1 Eyeball is a great flap position sensor in the RV9. Requires no power, and the only maintenance is safety glasses in the shop and a once-a-year visit to the Optometrist.
Yep, we think alike. Just a big paddle switch and eyeball verification.
 
I wired for a position sensor but didn't install. A count of 1000 to 1008 and I know I'm full down or up and 2 second increments when I need to deploy partial flaps.

However, installation of a sensor is up to the builder.
 
I have the FPS (before trim was available) and love it. One push of the momentary toggle switch advances the flaps to the next "notch". Each amount of flap deployment is the same every time. Toggle switch up brings them all the way up (or I can partially raise them by returning the switch to mid position). Keeps my eyes looking forward. I prefer to not have to turn my head 90+ watching the flaps deploy. I can hear and feel them moving. That's enough for me. Not much trim adjustment necessary.

Bevan

I've got this as well and love it. No guesswork about how much flaps you're putting in, and a go-around is a simple toggle-up with throttle-up and forget it. I'm not a fan of looking at a bunch of stuff other than the threshold while on short final, so I have my plane set up for HOTAS.
 
I used the Ray Allen POS-12 sensor and mounted it like this:

IMG_3396-M.jpg


Just bend up some scrap aluminum to make a bracket and flush rivet it on the back of the flap housing.

IMG_3890-M.jpg


The servo has about 1" of throw, so you can see that putting a cushion clamp down low on the flap weldment arm will result in having it use the full range.

Flaps down position - sensor arm fully in:
IMG_2457-M.jpg


Flaps up position - sensor arm fully out:
IMG_2458-M.jpg


The rod and clevis's are from a hobby store. The little tab that is held by the cushion clamp is made from some aluminum angle. The angle got cut down a bit, but still provides for some anti-rotation protection of the tab. Under the cushion clamp is some silicon fusion tape which also keeps the cushion clamp from moving around on the weldment arm.

I have the flap positioning capability from the Vertical Power VP-X box. On my Tosten grip control stick, I have one of the two top buttons used for "down" and the other for "up". The VP-X locks out those buttons above the flap extension speed you set, so there is no issue of accidently hitting the buttons during cruise. You can configure the flap positions to where you want them in the VP-X configurator software. I have mine set at 10, 20 and 30 degrees. One press of the down button gives you 10 degrees, another press to go to 20 and a third press to get full flaps. Or you can press the button 3 times rapidly if you want full flaps with no intermediate stops. One press of the up button brings them all the way up. I really like this set up. In the pattern, slow to 78 Knots, press down once to get 10 degrees on downwind, then use the hat switch on the stick to retrim to 70 Knots. Base at 65 Knots, do the same. Press down again to get 20 degrees, retrim. On your final leg, press down a third time to get full flaps, slow to 60 Knots, retrim and grease the landing.
 
Bruce, thanks for the helpful photos and write up. It's a shame on this forum that when one asks for help one sometimes gets a bunch of "I didn't do that so you don't need to do it either" type of comments. I don't ask questions anymore on this forum for that reason.
 
The MK-1 Eyeball is a great flap position sensor in the RV9. Requires no power, and the only maintenance is safety glasses in the shop and a once-a-year visit to the Optometrist.

That's what I installed in mine. Besides, with the -9 I use three positions. Full up, full down, and match to a down aileron when operating off of grass. This is not a Cessna so I feed in all the flaps abeam the touchdown point, trim it, and never touch them again for ALL landings, regardless of the wind speed or direction.
 
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For what its worth I tend to look at most things from a reliability and future maintenance standpoint and I believe it easy for new owners and builders to get all wrapped around all the cool gadgets one can install these days (I see this quite often).

So when you have an electronic flight control, rigging now becomes critical and surface position is now dependant on an "inexpensive" position sensor with somewhat questionalble repeatability. When I put the flaps up I just want them up, and I prefer a hard stop to a electronic position sensor. Secondly when the flaps quit someday (and they will), troubleshooting becomes much more difficult and time consuming with an electronic control system, not a good thing especially if you're away from home.

So in summary I'm a big believer in the KISS principle, I think the flaps are a good example of how to make a really simple system more complicated, with minimal reward.

PS: Asking question is great, but you better have your big boy pants on when you do, this can be a rough crowd, everyone means well, we just don't all agree.
 
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Bruce, thanks for the helpful photos and write up. It's a shame on this forum that when one asks for help one sometimes gets a bunch of "I didn't do that so you don't need to do it either" type of comments. I don't ask questions anymore on this forum for that reason.

My post was simply an expression of my OPINION and should be taken for what it's worth. When I was building I spent a lot of time and money building and installing some "optional" gadgets that I thought would be useful only to find that they are a waste of time and money and added to the complexity and weight of the airplane. If someone wants to put an in-flight refueling probe on their airplane should I suggest the best way to do it or point out the obvious inadvisability of continuing down that path? Extreme example, but I hope you get my point. When multiple posters point out that the M-1 eyeball is a super flap positioning instrument, perhaps the questioner might like to re-think about building a a gadget to indicate his flap position. Or he may not, but at least he got the input from many who have been there before making his decision. If you don't ask questions you will never get the benefit of the expertise available on this forum. You don't need a flame-proof suit when asking a question, just be aware that you are liable to get more opinions than you asked for. Take 'em or leave 'em. Your choice.

Respectfully
 
Bruce, thanks for the helpful photos and write up. It's a shame on this forum that when one asks for help one sometimes gets a bunch of "I didn't do that so you don't need to do it either" type of comments. I don't ask questions anymore on this forum for that reason.

I suppose for some, happiness can be defined by never hearing an opinion counter to your own. However, it is a detraction from expanding one's knowledge. I can think of numerous examples where I asked for advise and got counter opinions. After more research on those opinions, I felt better informed on the direction that I went, either following my own thought or the alternate thought proposed. It is very easy to ignore posts if they don't add value to your mission. Most everyone here means well, even if the wording and tone may not always be the best.

Larry
 
I suppose for some, happiness can be defined by never hearing an opinion counter to your own. However, it is a detraction from expanding one's knowledge. I can think of numerous examples where I asked for advise and got counter opinions. After more research on those opinions, I felt better informed on the direction that I went, either following my own thought or the alternate thought proposed. It is very easy to ignore posts if they don't add value to your mission. Most everyone here means well, even if the wording and tone may not always be the best.

Larry

Agreed completely with the exception that advise such as (paraphrase here) "I didn't do that so you don't need to do it either" hardly contributes to one's knowledge.
 
Back on topic.....

So I'm a low time pilot who completed an -8, ( you know over in the other threads:D)

While building I agonized over flap position also. Had been flying a DA-20 with 3 position flap switch. Figured that was the way it needed to be. Then I found an AFS 4500 and installed their AOA so I needed flap position. Turns out glancing out the canopy is way easier then looking at glass. Big, flat lever on a toggle switch. No regrets.
 
Bruce, I have the same setup as you with the Ray Allen position sensor and a VP-X Pro. Not sure what EFIS you have but I have a Dynon Skyview. I never got the flap positions to show up on the PFD. After multiple posts to Dynon and Vertical Power forums in which they ultimately suggested the other party was the issue, and verifying that I had it wired correctly, I never got it to work.

I have been flying for a year and a half relying on what Mike Seager taught me when I did my transition training, i.e., count to 4 for half flaps on downwind, another count to 4 on base for full flaps, and land. Has worked great but it has always bugged me I don't have the flap position showing on the PFD. (As an aside I have the same issue with the trim and have learned that counting to 4 while holding the trim down button during my pre-takeoff prep gets it pretty close to where it needs to be for takeoff.)

So, do you have a Skyview, and if so, do you remember how you configured your flaps?
 
So, do you have a Skyview, and if so, do you remember how you configured your flaps?

Yes, I have a Skyview EFIS. The VP-X configurator is what is used to set the range and the various stop positions for the flaps. You can also reverse the polarity of the flap motor voltage, so no worries about which wire is up/down.
I think the only thing required on the Skyview is to go into the EMS configuration and select that the flap position is coming from the VP-X data. Then configure a widget on the screen layout editor display to be tied to the flap position input. I have a different widget for the various screen partition sizes. On the full EMS screen, it is a quarter circle shape with a flap like pointer and on the narrow screen I just have degree numbers.

I'm pretty sure the set up is well documented in the Skyview Installation Guide.
See page 13-5.
 
Yes, I have a Skyview EFIS. The VP-X configurator is what is used to set the range and the various stop positions for the flaps. You can also reverse the polarity of the flap motor voltage, so no worries about which wire is up/down.
I think the only thing required on the Skyview is to go into the EMS configuration and select that the flap position is coming from the VP-X data. Then configure a widget on the screen layout editor display to be tied to the flap position input. I have a different widget for the various screen partition sizes. On the full EMS screen, it is a quarter circle shape with a flap like pointer and on the narrow screen I just have degree numbers.

I'm pretty sure the set up is well documented in the Skyview Installation Guide.
See page 13-5.

Ok, thanks! Maybe I'll give it another try.
 
I used the Ray Allen POS-12 sensor and mounted it like this:

Flaps up position - sensor arm fully out:
IMG_2458-M.jpg

For those choosing to use the sensor, the angle to the vertical is 30 degrees. I did a drawing to determine the ideal.
 
For those choosing to use the sensor, the angle to the vertical is 30 degrees. I did a drawing to determine the ideal.

Nice set up here. Mine is similar only the sensor bracket has a pivot point, though from fully up to fully down there is very little movement. It has worked flawlessly with no maintenance required in 600+ hours. Each annual I look at for any sign of issues as I inspect the flap motor and attachment points.
 
I have a question, why doesn't anyone use the Motion Systems actuator with built in feedback?

Motion Systems makes the exact same series actuator for every RV model WITH built in feedback. No need to mount up extra brackets and sensors. It's all done for you on the inside with a FAR superior pot than what's inside the POS-12.

It wires up just the same as the actuator with the external POS-12. Just seems like more work and more to go wrong with all that extra linkage as Walt pointed out.

If you really want flap position why not use the same motor with all this external stuff built in?

What if it breaks you ask? It'll last a lot longer and give you a much cleaner signal than the POS-12, trust me. If you put both the built in pot inside the actuator and the POS-12 pot on a scope you can visually see how superior the pot is inside the actuator compared to the POS-12.

I built my own digital flap controller and use the motor with built in feedback. No other hardware and brackets to mount.

No quite as simple as looking over your shoulder but a lot easier than mounting up all that ancillary stuff just to get flap position.

As stated earlier, my post is simply an expression of my OPINION and should be taken for what it's worth.
 
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Hi Walt,

It's very easy, just add "-POT" to the end of your current 85615 series part number for your RV model specific actuator. Not all RV models use the same actuator so your mileage will vary. :D

Note: as the stroke length on the actuators increases the center to center mounting distance on the holes MAY increase just a little. This means that the minimum retracted centerline distance might be slightly longer than the non feedback version. This is for the cover on the feedback pot. This is more noticeable only on the longer stroke models.

You can check this on the Motion Systems website.

Shawn
 
So when you have an electronic flight control, rigging now becomes critical and surface position is now dependant on an "inexpensive" position sensor with somewhat questionalble repeatability. .

I agree with that, which is why I am only using the sensor for a cockpit indication. If it breaks I can look over the side to verify. The motion of the flap motor will be completely independent of the sensor. It is a bell and whistle that is not strictly required, but it is easy to do and cheap and my EFIS has the capability so for the sensor cost and $5 of wire I will have the flap and pitch trim displayed.
 
Flap Position Indication at Night

Not having done it, is it easy to see the flaps at night?

The answer is no, unless you use a flashlight or if you have a light of some sort illuminating the flaps from the cockpit. This is the single best reason for having a flap position indicator, in my opinion. If you never fly at night or never fly IFR, then you probably don't need it. The RV-10/RV-14 guys, because of the reflex position, probably have further justification for having the gauge.
 
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For those that are considering,.... RV Flaps are not a precision tool. Mike Seager teaches a two step approach, flaps half when abeam the threshold, full on base. My home field is a tight short field. I typically dump all of my flaps when I am abeam and make a "short approach".
If you need an indicator to do this, or even need to "see" what is going on your not in touch with your airplane.

So, I am definitely in the camp of the KISS principle when it comes to the flaps. However, people like gadgets and will justify their use. Nobody wants to be accused of putting something in that wasn't necessary or useful.
I simply don't find flap operation, as designed by Vans, to be an area of concern under any circumstance that I have encountered.
 
Flap Positioning for IFR Approach

So - when I built my RV-7, I didn't bother to install any sort of flap position sensor or controller. Looking outside at the flaps has worked just fine for VFR flight. Fast forward 4 years, and I am now working on my IFR ticket. My instructor and I worked out that 90 knots seems like a good approach speed - but to get good stability with the pitch and power settings requires just a bit of flap. Problem is the repeat-ability of the "one-a-thousand, two-a-thousand, three-a-thousand" method of flap deployment. I have a piece of masking tape on the flap at the moment to help me get a handle on it, but of course that wouldn't work at night. Was really considering a position sensor to read out on my Dynon Skyview. I don't think I want the extra complexity of a full blown flap position controller.
 
So - when I built my RV-7, I didn't bother to install any sort of flap position sensor or controller. Looking outside at the flaps has worked just fine for VFR flight. Fast forward 4 years, and I am now working on my IFR ticket. My instructor and I worked out that 90 knots seems like a good approach speed - but to get good stability with the pitch and power settings requires just a bit of flap. Problem is the repeat-ability of the "one-a-thousand, two-a-thousand, three-a-thousand" method of flap deployment. I have a piece of masking tape on the flap at the moment to help me get a handle on it, but of course that wouldn't work at night. Was really considering a position sensor to read out on my Dynon Skyview. I don't think I want the extra complexity of a full blown flap position controller.

I would amend my previous statement and add if it reduces your workload....
I would speak with folks who regularly fly RV?s IFR and see.....
 
For those that are considering,.... RV Flaps are not a precision tool. Mike Seager teaches a two step approach, flaps half when abeam the threshold, full on base. My home field is a tight short field. I typically dump all of my flaps when I am abeam and make a "short approach".
If you need an indicator to do this, or even need to "see" what is going on your not in touch with your airplane.

So, I am definitely in the camp of the KISS principle when it comes to the flaps. However, people like gadgets and will justify their use. Nobody wants to be accused of putting something in that wasn't necessary or useful.
I simply don't find flap operation, as designed by Vans, to be an area of concern under any circumstance that I have encountered.

I am 100% in this camp with the RV-9, especially fixed pitch RV-9's and -9A's!

IFR is a different story and you need to fit in the system, when doing an approach IFR.

Because of the high lift Roncz airfoil and long wing on the -9, its landing speeds are much different than the short wing RV.

My recommendation, regardless of crosswinds in the -9 is to put out all the flaps abeam the numbers, trim it for 60 knots when heavy and 55 knots when light. Then fly the entire pattern at that speed.

This gives the -9 pilot the ability to fly a VERY stabilized approach while flying well above the stall speed.

It also means you only need two flap setting, all the up or all the way down.

For short and/or soft fields, I lower the flaps to match the down aileron, which works out very well.
 
I am 100% in this camp with the RV-9, especially fixed pitch RV-9's and -9A's!

IFR is a different story and you need to fit in the system, when doing an approach IFR.

Because of the high lift Roncz airfoil and long wing on the -9, its landing speeds are much different than the short wing RV.

My recommendation, regardless of crosswinds in the -9 is to put out all the flaps abeam the numbers, trim it for 60 knots when heavy and 55 knots when light. Then fly the entire pattern at that speed.

This gives the -9 pilot the ability to fly a VERY stabilized approach while flying well above the stall speed.

It also means you only need two flap setting, all the up or all the way down.

For short and/or soft fields, I lower the flaps to match the down aileron, which works out very well.

The "all flaps out abeam the numbers" idea works pretty well for low-traffic airports, but trying to fit in with a fair bit of business traffic at a busier airport makes it a little more interesting. I fly my 9A into work frequently and there is a rush of King Airs and Lears coming in right around the same time I typically arrive at the non-towered field. It's not unusual for me to pass abeam the numbers at 130 KIAS and then throw out the anchor to fit in with the other traffic. The constant speed prop makes an excellent airbrake and it's not hard to slow it down for even a tight turn to short final. Preferred technique? Certainly not - but it can be done.

IFR approaches are pretty stable in the 9A at 90 knots, and it does like about 10 degrees of flaps for that. I use the Showplanes flap positioning system, three bumps down of the momentary switch (on the stick) for 10/20/full on the flaps, and then flip the switch up for full retract and stop. It makes go-arounds so simple - power up, nose up, flaps up - just about that fast and you don't have to worry about counting seconds for the flap extension/retraction, much less take your eyes off the panel to visually check them.
 
Hey Greg, I got a question for you... (and yes... there are dumb questions, we all know that)
To make use of slowing with your CS prop, do you pull the pitch back or shove it in? I don't have that prop, but have been teaching the new owner how to best use his Hartzell.
And for those who don't use a flap indicator... I used a protractor and found 10 degrees. There is a sharpie mark on the flap itself. I can see that mark day or night looking over my shoulder. The mean time between failure was calculated at 36,000 hours. By then the rain will have taken it's toll.
 
I haven't bothered with shoving the prop to full RPM, though it would increase the drag due to more engine braking. I've found that my normal 2500 rpm cruise setting with closed throttle is quite sufficient. I use 2700 rpm for takeoff but generally not for touch-and-goes or landings as the additional energy is simply not needed unless I'm loaded to the gills or at high density altitude. With any decent amount of forward energy already available the engine at 2500 rpm will make it jump right back off the ground again for a rejected landing or go-around.
 
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