Nasa Clipper Wireless Wind System - reading low

[DartGra]

Having recently fitted a new Nasa Clipper Wireless Wind System to our Moody S31 we seem to be getting readings several knots below the actual. I'm guessing maybe as much as 20% low.
We checked with NASA and confirmed there is no way we can calibrate the system. Their advice is to see if the mast top stuff is damaged in any way.
We wondered if any contributers have experienced similar problems with the Nasa Clipper Wireless Wind System and if / how it was overcome.

 

[oldharry]

I had one on a previous boat, and found after 2 winters of gales the bearings failed in the MH unit, giving readings that were increasingly adrift as the wind speed increased. Replacement did the same after 18 months. A second replacement made of different plastic was still fine when the boat was sold some years later. Could be yours has a faulty bearing as suggested by Nasa. It should be possible to rotate the Cups by blowing on them and they should spin freely. Not so easy at the masthead though!

 

[DartGra]

Thanks OldHarry. Looks like a trip up the mast and testing the MH head unit as you describe.:ambivalence: