Heated pitot for RV-12iS?

[CTCole]

Without re-igniting the previous thorough & informative threads on the suitability & legality of operating an RV-12 in IMC, has anyone installed a heated pitot/AOA system in their -12, willing to share details? Location and attachment of mast & controller; location, size, and attachments of wiring; use (or not) of a relay; etc. What worked or should be different?

--Chris

 

[rongawer]

Here you go

Hi Chris, I was going to respond to your PM, however, I have been asked this same question several times, so I thought I'd just go ahead and post.

DISCLAIMER: For the sea lawyers in the crowd, the information provided below is not for E-LSA builders.

I did not install the mechanical stall tab and my pitot is not in the spinner. I have a Garmin GAP 26 heated probe with AOA installed on a Gretz mounting tube installation kit.

(I think properly calibrated AOA is a much better indicator of stall indication than tab that can easily get bent... free advice for another topic)

I installed my probe in the 6th bay going outboard from the wing walk, or 5th bay inboard from the wing tip bay. It is mounted forward of the spar - if you mounted aft of the spar it would be well outside of the chord line requirement. I used two J stringers to provide a firm mounting for the mast between the two wing ribs. This location provided a very good place for accurate airspeed and AOA indication.

Works great for IMC...

 

[thiggins]

eh?

(not trying to hijack a thread...)

E-LSA becomes experimental after issuance of the airworthiness certificate...
So, I'm not understanding your statement concerning the change and E-LSA.

https://www.kitplanes.com/understanding-experimental-light-sport-aircraft/

https://vansairforce.net/community/showthread.php?t=191858

 

[rongawer]

(not trying to hijack a thread...)

E-LSA becomes experimental after issuance of the airworthiness certificate...
So, I'm not understanding your statement concerning the change and E-LSA.

https://www.kitplanes.com/understanding-experimental-light-sport-aircraft/

https://vansairforce.net/community/showthread.php?t=191858

You led with the answer. Note I used the term “builder”, which I mean to be actively building. Unless Vans changes their E-LSA design to include this method I described, which is highly unlikely, the aircraft won’t meet E-LSA certification. MANY threads on this.

I’m not sure who would want to perform a rather significant change after the airplane is built, but to each their own. Enjoy.

 

[Handclutch]

I installed a Gretz heated pitot in a flying legacy RV12. It's in the stall warning inspection panel with a doubler 3"-4" wide running from the rear of the opening back to the spar to provide stiffening. Several hundred hours and no issues.

It draws 7 Amps but is only on for about 15 seconds in each minute and a half - average current draw is quite minimal.

As for accuracy - initially I flew with both pitots installed and each connected to a separate EFIS (D180 and G5). They were within a knot of each other over the entire speed range except for just above the stall where there was a 3-4 knot discrepancy. I assumed that was something to do with the different locations but found it was still there after removing the original pitot. Just a difference within the instruments.

Jack

 

[12vaitor]

I installed a Dynon heated pitot on a Gretz mast in the bay with the Stall Warning switch. My install was done after the wings were closed in, so all the work had to be done through the Stall Warning access panel hole.

I cut the Gretz mast hole first on the outside wing skin, then added a 4" wide doubler that goes the entire width between the ribs. The doubler is stepped on one side to sit above the rib flange and is riveted through the existing wingskin/rib holes on one side and has a 90 deg bend on the other side that is riveted through the side of the other rib. There is a slight curve, so you have to do some shrinking on the ends. The doubler is also riveted on the front and aft part to the wing skin between the ribs. The controller box is mounted on the backside of the stall warning access cover plate. That was done so that only two 14ga wires for power had to be run through the wing. I used two 1/4" quick disconnect bulkhead tubing connectors and a mil-circular power connector to retain the removable wing capability.

This is a lot easier to do if the top wing skin is open, but only if you are going EAB on a new build plane. I am surprised that Van's does not offer an optional kit for a heated pitot on the -12iS with the IFR package. The -12 AOA retrofit kit has a lot of the parts needed for the pitot plumbing.

John Salak
RV-12 N896HS

 

[12vaitor]

I installed a Dynon heated pitot on a Gretz mast in the bay with the Stall Warning switch. My install was done after the wings were closed in, so all the work had to be done through the Stall Warning access panel hole.

I cut the Gretz mast hole first on the outside wing skin, then added a 4" wide doubler that goes the entire width between the ribs. The doubler is stepped on one side to sit above the rib flange and is riveted through the existing wingskin/rib holes on one side and has a 90 deg bend on the other side that is riveted through the side of the other rib. There is a slight curve, so you have to do some shrinking on the ends. The doubler is also riveted on the front and aft part to the wing skin between the ribs. The controller box is mounted on the backside of the stall warning access cover plate. That was done so that only two 14ga wires for power had to be run through the wing. I used two 1/4" quick disconnect bulkhead tubing connectors and a mil-circular power connector to retain the removable wing capability.

This is a lot easier to do if the top wing skin is open, but only if you are going EAB on a new build plane. I am surprised that Van's does not offer an optional kit for a heated pitot on the -12iS with the IFR package. The -12 AOA retrofit kit has a lot of the parts needed for the pitot plumbing.

John Salak
RV-12 N896HS

Added some photos for reference.

 

[CTCole]

Thanks for the descriptions & photos! These are going to help.

--Chris

 

[30752mr]

Here you go

Hi Chris, I was going to respond to your PM, however, I have been asked this same question several times, so I thought I'd just go ahead and post.

DISCLAIMER: For the sea lawyers in the crowd, the information provided below is not for E-LSA builders.

I did not install the mechanical stall tab and my pitot is not in the spinner. I have a Garmin GAP 26 heated probe with AOA installed on a Gretz mounting tube installation kit.

(I think properly calibrated AOA is a much better indicator of stall indication than tab that can easily get bent... free advice for another topic)

I installed my probe in the 6th bay going outboard from the wing walk, or 5th bay inboard from the wing tip bay. It is mounted forward of the spar - if you mounted aft of the spar it would be well outside of the chord line requirement. I used two J stringers to provide a firm mounting for the mast between the two wing ribs. This location provided a very good place for accurate airspeed and AOA indication.

Works great for IMC...

I have an RV12is and would like to install Gap 26. The only part of this process that I cannot figure out is where you are getting the power from. I don't see a power buss that looks familiar firewall forward or in the avionics bay. Can you show how you wired yours?

 

[CTCole]

I ran a wire from the ship side of the master solenoid, as shown in the attached figure. Color doesn't come out well in this scan. Wires at the Molex connector going to the controller are blue (top, unused signal wire), red (in the middle), and black (bottom). Not shown is that the wires (except for the unused, blue signal wire) are 14 ga. You could take the power from the AV-60000, the red screw connecting a wire to the input side of the starter solenoid.

 

[30752mr]

I ran a wire from the ship side of the master solenoid, as shown in the attached figure. Color doesn't come out well in this scan. Wires at the Molex connector going to the controller are blue (top, unused signal wire), red (in the middle), and black (bottom). Not shown is that the wires (except for the unused, blue signal wire) are 14 ga. You could take the power from the AV-60000, the red screw connecting a wire to the input side of the starter solenoid.

Thanks Chris. That should get me going in the right direction.