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  #1  
Old 07-11-2020, 10:33 AM
PhatRV PhatRV is offline
 
Join Date: Mar 2018
Location: Buena Park, California
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Default Question on Location of ADAHRS in Relation to Static Port

I am relocating my ADAHRS to a place that is easier to maintain. However, the location of the ADAHRS is lower than the location of the static port. The embedded picture below shows the relative location of the ADAHRS and the static port. The static line is tee-off from a location near the top longeron to mitigate any moisture condensation and runs forward to the front panel. The static line is tee again downward toward the ADAHRS, and its location is slightly lower than static port in level flight. When the airplane is sitting tail down, both are located at about the same level.

Question: Is this location acceptable in term of mitigating moisture condensation with the distance between the static port and the ADAHRS is about 36inches? Are there other problems with this setup? Thanks.

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Last edited by PhatRV : 07-11-2020 at 10:46 AM.
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  #2  
Old 07-11-2020, 01:22 PM
Carl Froehlich's Avatar
Carl Froehlich Carl Froehlich is offline
 
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Location: Dogwood Airpark (VA42)
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I?d guess that static line routing will work.

I note however this ADAHRS location puts them near the pitch autopilot servo and the rear battery (if mounted aft). I?d be more concerned about that than the static line.

I mounted both SkyView ADAHRS modules on a piece of pre-preg that goes between the upper longerons, just aft of the baggage compartment bulkhead. This location has worked out well WRT magnetic interference.

Carl
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  #3  
Old 07-11-2020, 01:41 PM
RVDan RVDan is offline
 
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Location: Frederick, MD
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Quote:
Originally Posted by PhatRV View Post
I am relocating my ADAHRS to a place that is easier to maintain. However, the location of the ADAHRS is lower than the location of the static port. The embedded picture below shows the relative location of the ADAHRS and the static port. The static line is tee-off from a location near the top longeron to mitigate any moisture condensation and runs forward to the front panel. The static line is tee again downward toward the ADAHRS, and its location is slightly lower than static port in level flight. When the airplane is sitting tail down, both are located at about the same level.

Question: Is this location acceptable in term of mitigating moisture condensation with the distance between the static port and the ADAHRS is about 36inches? Are there other problems with this setup? Thanks.

You run the chance of condensate draining into the ADAHRS, so unless the vertical run is very short and the T is at a high point, I would not do it.
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  #4  
Old 07-11-2020, 02:50 PM
PhatRV PhatRV is offline
 
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Location: Buena Park, California
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Quote:
Originally Posted by RVDan View Post
You run the chance of condensate draining into the ADAHRS, so unless the vertical run is very short and the T is at a high point, I would not do it.
That is my main worry too. I have to find a solution to check for condensation and method to quickly drain out the line if there is water in the line. Perhaps an access port at the rear luggage compartment to allow me to check for condensation during pre-flight, especially after a rainy day.

Quote:
Originally Posted by Carl Froehlich View Post
I’d guess that static line routing will work.

I note however this ADAHRS location puts them near the pitch autopilot servo and the rear battery (if mounted aft). I’d be more concerned about that than the static line.

I mounted both SkyView ADAHRS modules on a piece of pre-preg that goes between the upper longerons, just aft of the baggage compartment bulkhead. This location has worked out well WRT magnetic interference.

Carl
Agree with the interference. Unfortunately only location that is sufficiently away from a magnetic source is closer to the rear-frame near the static ports. I can squeeze into the area to monkey with the ADAHRS but it is a chore. I can imagine this will get more difficult as time goes on as my body isn't a limber . I've decided to purchase a stand alone magnetometer and mount it inside the wingtip which allows me to locate the ADAHRS at a more convenient position. I can also raise it to the above the longerons just aft of the luggage compartment frame, which will also solve the condensation problem. Then I don't worry about my luggage containing ferrous material.
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Last edited by PhatRV : 07-11-2020 at 02:53 PM.
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  #5  
Old 07-11-2020, 05:04 PM
David Paule David Paule is offline
 
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Location: Boulder, CO
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For the aft location, can you gain access through the F-810A bulkhead?

On my small RV-3B, that's my plan. Here's the equivalent bulkhead, smaller than yours, and my mount for the Dynon ADAHRS, shown before the top skin went on. I can install, secure and remove the ADAHRS with only a bit of difficulty.



The odd mount is designed to have the ADAHRS slide in from the rear and then be forced against the forward plate by redundant zip ties.

Dave
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  #6  
Old 07-11-2020, 05:47 PM
wirejock's Avatar
wirejock wirejock is offline
 
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Default Adahrs shelf

Vans has a new kit to mount the ADAHRS up between the top skin stringers.
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  #7  
Old 07-11-2020, 07:30 PM
rapid_ascent rapid_ascent is offline
 
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You can still make a loop of the static line by your AHRS. The AHRS platform is 2 or so inches off the bottom skin. For my Garmin GSU25 AHRS units with the static fittings sit maybe 3 inches above the platform. I ran the static line forward through the bulkhead and down almost to the floor then it loops up to the AHRS. I think it?s enough of a drip loop.
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  #8  
Old 07-12-2020, 06:17 PM
PhatRV PhatRV is offline
 
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Location: Buena Park, California
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Quote:
Originally Posted by rapid_ascent View Post
You can still make a loop of the static line by your AHRS. The AHRS platform is 2 or so inches off the bottom skin. For my Garmin GSU25 AHRS units with the static fittings sit maybe 3 inches above the platform. I ran the static line forward through the bulkhead and down almost to the floor then it loops up to the AHRS. I think it?s enough of a drip loop.
Thanks for the drip-loop idea. I will build it now that the ADAHRS is mounted in the new place.

Quote:
Originally Posted by David Paule View Post
For the aft location, can you gain access through the F-810A bulkhead?

On my small RV-3B, that's my plan. Here's the equivalent bulkhead, smaller than yours, and my mount for the Dynon ADAHRS, shown before the top skin went on. I can install, secure and remove the ADAHRS with only a bit of difficulty.



Dave
Dave, I mounted mine close to this bulkhead too. After I connected the elevator pushrod, it is difficult to gain access unless I remove the pushrod and crawl sideway inside this narrow section after the backshell is closed. With the temperature in the 90degF this week, it gets hot very quickly inside and my glasses got fogged up after a few minutes. Since I have the Dynon ADAHRS I may have to recalibrate the pitch attitude of the device after the first few flights. I decided I rather not crawl again into this space hence the decision to move it forward.
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  #9  
Old 07-13-2020, 01:01 AM
emsvitil's Avatar
emsvitil emsvitil is offline
 
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Put a T at the ADAHRS with the line going down past it.

Then put a drain valve on the bottom of that line.
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