What was found
ON FINAL APPROACH AT 125 KTS IAS, LT PROPELLER RPM DECREASED FROM 1020 RPM TO 980 RPM. INTERROGATED CDS. NO FAULTS FOUND. COMPLIED WITH ENGINE TREND DOWNLOAD MAINTENANCE 6773101. VERIFIED MEASURED BETA CALIBRATION MEASURMENT TO BE WITHIN LIMITS. REMOVED AND REINSTALLED BETA TUBE IAW MAINTENANCE 6610001 AND 6610002. ALL OPS TESTS GOOD. NO LEAKS NOTED. NO PROP RPM FLUCTUATIONS NOTED DURING RUNS. RETURNED TO SERVICE.