As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BOTH STBY AIRSPEED INDICATORS FROXE AT 120KTS PASSING 10000'. BOTH DCREASED THE SAME TO 90KTS AT 350. DURING DESECENT BOTH DECREASED TO 60KTS. DISCONNECTED STANDBY PITOT PROBE AT BACK (42DA).BLEW OUT PITOT PROBE, FOUND DIRT IN PROBE. IAW M/M 34-10-00-03. RECONNECTED PROBE. PERFORMED BOTH LEAK DOWN TEST AND TEST OF STANDBY PNEUMATIC CIRCUIT BOTH PASS IAW M/M 34-10-00- 05. A/C OK FOR SERVICE. PER 34-10-00-03 SECOND MECHANIC VERIFICATION OF LINE RECCONECTION.