Anybody know whether this is an airworthiness issue? I was flying CAP cadets
today and discovered the problem. We have a kid taking a private ride on Monday
and would not like to switch airplanes on him.

Obviously it's not on the required VFR equipment list, but since without it you
no longer know the airframe or engine hours for ADs, inspections, etc. it seems
to me that there is likely to be a requirement for it buried somewhere.

TIA