Moment arm Question

[Dave Piehler]

Does anyone happen to know the correct moment arm for the aft wing inspection panels in which the strobe power packs are mounted for a 201?  The Service Manual (Fig. 6-3) shows the spar should be STA 53.00, and the aft of the wing at the fuselage is approx. STA 88.00, but since the wing tapers you can't go by that.  Failing any other solution I suppose one would take off the panel and measure from the midpoint of the opening to the spar, but I thought perhaps one of the resident Mooney savants might know this offhand and save me the trouble.

[M20F]

Did you add or change something?  It seems like you added strobe power packs and want to update your W&B but your question isn't entirely clear to me.

[N601RX]

Check the original factory w&b. If your lucky they will show the arms.

[Dave Piehler]

Factory W&B lists the strobes, but the listed weight is too light to include the power supplies aa well.  Complicating this was that the original Hoskins power packs were replaced by Whelens a few years ago, in different access panels.  My original post was made from home with the POH in the plane, of course.  Now that I can reference the POH I see that the  mechanic who installed the Whelens made a W&B entry that gives the necessary info.

The reason for the question was that the Whelen strobes have now been removed and replaced by LED strobes/position lights.  Why?  it seems the G500 magnetometer in the wing is sensitive to electromagnetic interference from wiring in the wing that uses the fuselage s a ground path  The new lights have a return wire and run in shielded wiring.  The reduced current draw is also nice now that my plane has lots of electronic gizmos.

[MB65E]

Just measure it from the distance aft of the nose pivot datum.  Probably someplace extremely close to the rear seat arm.

-Matt