O. Sami Saydjari wrote:

/snip/Isn't there a way to judge true accuracy of
speed indicators (just as there is for altimeters)? Should I be
satisfied with my mechanic's answer and move on?

-Sami
N5554G, Cessna 421C

Sami,

There certainly are maintenance actions you can take to ensure your
airspeed indications are as accurate as possible. Both airspeed
indicators can be sent to an instrument shop for check/overhaul. Any
competent mechanic can check your pitot and static systems for leaks and
/or abnormalities. Once these are all done, your system will be as
accurate as originally designed. Keep in mind that *some* aircraft are
designed so that one side is accurate at lower speeds, and the other
accurate at higher speeds, but I doubt this is the case with a twin
Cessna. The above info does not infer whether the expense incurred
would be worth the outcome, that is a decision only you can make.

P.S. When did you sell your Turbo Arrow and get that bottomless money pit?

Happy Flying!
Scott Skylane