inclinometer off on the ground (static)

[landwerlen]

im sure there is a thread on this already, but i've failed to locate one. we've got an S-LSA with the D100 already installed. The slip/skid indicator (inclinometer), always shows a slightly left ball indication in a static condition. we use that indication as 'neutral' and have been flying that way for over a year. could the remote compass be installed erroneously? is there a way to 'center' the ball with software? thanks

 

[khorton]

Is it possible that the EFIS is installed so it is rotated slightly in the panel? I.e. is the right side of the EFIS slightly higher than the left side?

 

[landwerlen]

its not impossible, but the panel was designed and cut on a cnc device. im guessing there is an internal accelerometer that is causing me a problem. to cause such an error would require a fairly noticable installation angle. im definetly going to follow up on any good advice. thanks

 

[dynonsupport]

The sensors that are reflected as the inclinometer are inside the EFIS itself. We calibrate each unit here, so there are two possibilities: either the unit is installed slightly tilted, or the unit is out of calibration. We're happy to take a look at the unit under warranty to help you figure out which it is. Historically, though, just about every unit that has come back for this problem has checked out OK here.

 

[landwerlen]

can u quantify 'slightly'? 0.1 degrees? 1 degree? i'll measure it next week with a digital protractor to give a more descriptive error, but ive got it well under half a degree (probably closer), and the ball is intersected by the left line almost in half. thanks

 

[DBRV10]

Check the floor of your hangar, we had the same issue with our last plane, the D10 always showed a bit of left down, we think it was the plane and its undercarriage plus the slight slope on the concrete.

Was fine in the air when flown accurate.

Most likely you have a similar problem!

 

[PhantomPholly]

Yep, airplanes don't always sit "level" on their gear - especially if the floor is tilted!

 

[dynonsupport]

Roughly speaking, a half ball deflection is about 2 degrees, while a full ball is close to 4. It takes about 3/4 degree to get the ball start crossing one of the lines, and just tenths to get it to be non-centered.

 

[DBRV10]

Thanks DS, I now know the slope of the concrete in the hangar! ;D