Instrument Maintenance

I know a certain method is specified for ASI calibration. But it seems unnecessarily complex and error prone.

EASIER, MORE ACCURATE METHOD (but not “approved”):

-Choose any runway of any given length.

-Fly down the runway with a stop watch, recording the time from end to end, and recording the ASI indicated airspeed.

-Do it all again in the opposite direction holding the same altitude and indicated airspeed.

-Calculate the average time of the two timed passes.

-Convert that time to speed by accounting for the runway length.

-Compare this to the indicated airspeed and record the ASI readings and the average of the calculated speeds.

DONE!

(This is essentially the method used to verify competition flight speed tests.)

Gents; Exactly the kind of info I'm looking for. Thanks! Mike

Check AD2012-08-06. The airspeed indicator needs calibration and marking verification every 4 years or anytime the pitot static system is worked on.

Coupers: I really, REALLY hate to ask dumb questions (at least in public!), but here goes anyway. What, if any, maintenance or calibration is required on my old fashioned steam gauges? I can find requirements for IFR-certified aircraft, but I am strictly VFR. I'm aware of the required transponder and encoder checks & certs. Anything else? I ask because my plane is apart for a "deep", extensive annual, and if anything instrument-related is required (or needs to be looked at) then now would be the time to do it. Thanks for your help and patience. Cheers! Mike Simmons N99622.