C

cajunbird

I'm New Here
I'm having problems with my Navaid wing leveler. I have not flown my RV7A but am very close to FAA inspection. The company is apparently out of business.
When I engage the wing leveler option on my wing leveler, the servo forces the ailerons into a full right turn. I can override this, but I can't figure out what is wrong.
 
Cajun,
Do you have the manual for the Navaid? I have this A/P in my RV-6 and also have the manual for installation and setup.
Let me know if I can be of assistance.
 
Possible causes

cajunbird said:
I'm having problems with my Navaid wing leveler. I have not flown my RV7A but am very close to FAA inspection. The company is apparently out of business.
When I engage the wing leveler option on my wing leveler, the servo forces the ailerons into a full right turn. I can override this, but I can't figure out what is wrong.
Click to expand...

Possible causes:
  1. The center of travel is misaligned with the stops on the servo shaft.
  2. Wiring.
  3. The servo is mounted perpendicular to it's normal direction and the shaft has not been adjusted.

Troubleshooting. You'll need an observer.

  • Level the aircraft.
  • Disconnect the linkage from the servo actuator arm.
  • Center the knobs on the control unit.
  • Place the switch in the center position (T/C)
  • Apply power to the control unit.
  • Listen for gyro spinning up. No spin up, bad gyro motor, end test.
  • Look at display. Red bar should be in center (or close). If not, bad control head, end test.
  • Place the switch in right position (W/L).
  • Move the turn knob left and right. Does the servo respond? If not, wiring problem (probably a short or open on the control line), end test.
  • If the servo moves to one of the stops but responds to the control head you need to rotate the control arm.
  • If the servo moves to one of the stops, but does not respond, you have bad control head, or much more likely, the control line is not connected/misconnected.

As with all free advice, YMMV. BTW, I have a Navaid and have flown it for 200+ hours, trouble free.

Must make darn sure you have not reversed or missed a pin in the connector (as I did on my first try) and that you have oriented the control arm properly.

Best of luck.
 
Hi Doc, welcome.......

....I don't know if the Navaid is similar to my TruTrak but it did the same thing during testing. After you get in the airplane with the engine running, the internal gyro will stabilize and they recommend to not move for ten seconds to enable it to do so.

When I start taxiing, it shows my track digitally and after I level off and engage it, it holds altitude and heading well.

Mine goes "tick...tick...tick"...in the hangar and ends up with a fully deflected stick, which I found out is normal with it engaged, sitting still.



Regards,
 
john

Thanks guys. Joe's comments are being looked into. The servo is mounted vertically(item #3 on Joe's list), however, the manual specifically allows this. I have the servo mounted on the outboard(right) wing rib(for easier access) with an 1/8" flat plate mounting bracket(riveted to the wing rib) supporting the servo to minimize torque problems on the wing rib. I have a push a half inch aluminum tubular push rod connecting the servo arm to the aileron bellcrank assembly. The length of travel of the servo arm/push rod has been adjusted for this.
As there are only 3 colored wires(item #2 on Joe's list) coming out of the servo unit, and 3 discreet positions for these wires in the control unit, I can't see how that could be a problem in the wing leveler mode with the aircraft setting solidly on the ground.
The unit has the appropriate response during the "warm up" and you can definitely hear the gyros humming(regarding Pierre Smith's comment). The red lighted indicator ball is in the center position of the LED scale.
Don't know how to determine the center of travel alignment with the stops on the servo shaft. Item #1 on Joe's list.

Joe's "checklist"
Level the aircraft. Done
Disconnect the linkage from the servo actuator arm. Will need assistant
Center the knobs on the control unit.
Place the switch in the center position (T/C)
Apply power to the control unit.
Listen for gyro spinning up. No spin up, bad gyro motor, end test. No problem
Look at display. Red bar should be in center (or close). If not, bad control head, end test.
Place the switch in right position (W/L).
Move the turn knob left and right. Does the servo respond? If not, wiring problem (probably a short or open on the control line), end test.
If the servo moves to one of the stops but responds to the control head you need to rotate the control arm.
If the servo moves to one of the stops, but does not respond, you have bad control head, or much more likely, the control line is not connected/misconnected.

Thanks for the ideas/assistance. I'm not ready to give in yet. This is one problem amongst about a thousand over the past 4 years that I've had to solve. We'll see if we can resolve it. Be back with you guys asap. John
 
John:

First of all welcome to the forums. Good to see another fellow molar mechanic here!

From your description, it sounds like you need to reposition the servo arm. When you power up the system and the servo goes to its extreme amount of travel, does it sound like it is loading up?

Another possibility is that sometimes the servo needs to have its direction of travel reversed due to installation configuration. I am not certain that this could be a factor, but perhaps it is.

I am certain that this can be solved by an adjustment from what you are telling us. We'll get to the bottom of it. I will check my manual today and see if I find a possible cure.

Regards,
 
Last edited:
john

response to Whiskey Papa:

I'll be glad to send photos of my wing leveler installation. As I'm not familiar with submission of photos on this site(new user on VAF forum), you'll have to give me instructions. Might be easier to simply email you directly with the photos attached. Couldn't open the link to the Navaid assistance site.

reponse to painless:


not sure what you mean by "loading up". The "problem" is notice in either wing leveler mode or track mode. The servo directs the ailerons to either a hard right or left turn depending upon whether I have the control stick center a little to the right or left. Feels a lot like being on a seesaw at a playground with an elephant on one side. Centered, directly over the fulcrum point, you're fine. Move the elephant just a little to one side and you're "committed". I've read and reread the manual supplied with my Navaid unit. Can't see a description of the problem that I'm having. Not being able to contact Navaid(AWOL), I'm stuck to figure it out. What I'm really trying to do is see if the control unit is bad. If that's the case, I'll simply have to punt and get a TruTrak or other compatible brand wing leveler and make it fit my panel.
 
John:

Ok, now I understand. It is an "all or nothing" situation.

Two possibilities for you. I originally had the complete Navaid system in my 6A, but then changed the control head to a Trio. With a connector adaptor, it functions with the navaid servo. If you find that your Navaid head is indeed TU, you can go with the Trio. It would drop right into the same hole in your panel and is about 1/2 the depth of the navaid if not less.

Another thing to consider. If all else fails and you find no cause other than the Navaid head possibly being the culprit, I would be happy to send you mine to see if it does the same thing. If it doesn't, then make me an offer.

Regards,
 
Trio

Have had 2 Navaids and have had the same problem, but in flight. Navaid fixed the problem, but didn't have an easy time doing it. I eventually took out Navaid and replaced with a Trio. Took about 30 minutes for retro fit, very happy with unit, didn't even have adjust any thing.

Steve Barnes the Builders Coach
 
Navaid Follow Up

Does anyone know if anybody works on the Navaid heads? Maybe one of the fellows that worked there? :confused:
 
You must log in or register to reply here.