Service difficulty report · Powerpack · Pilats PC1247

Difficulty date
June 5, 2009
Submitted
October 23, 2009
Operation
General aviation
Make and model
Pilats PC1247
Engine
Pwa PT6A67
Part
Powerpack
Part number
9603101154
Condition
Inoperative
Location
Hyd System
Part time
41 hours
Stage of operation
IN
How discovered
O
Nature of condition
B
Precautionary procedure
K

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

FLIGHT CREW REPORTED A HYD FAIL INDICATION AFTER GEAR SELECTION ALSO WITH A BRIEF AIR GROUND WARNING. A NORMAL GEAR DOWN SELECTION WAS MADE FOLLOWED BY A NORMAL LANDING. MX INVESTIGATION FOUND THE MAIN 100 AMP HYD PUMP CB WAS TRIPPED. CB WAS RESET AND THE PUMP WAS OPERATED, SHORTLY AFTER, A BURNING ODOR WAS NOTED AND THE CB WAS PULLED. THE CONNECTIONS WERE CHECKED ON THE HYD MOTOR AND THE PUMP WAS OPERATED AGAIN. DURING THE SUBSEQUENT GROUND OPERATION, HYD MOTOR STOPPED OPERATION AND THE SOFT START RESISTOR TO THE HYD PUMP MOTOR BEGAN TO GET VISIBLY HOT. THE 100 AMP POWER CB WAS MANUALLY PULLED. A FURTHER INSP NOTED THE LT WING TO FUSELAGE COMPOSITE PANEL EXHIBITED A SMALL AREA OF HEAT DAMAGE FROM THE ADJACENT SOFT START RESISTOR. HYD PWR PACK WAS REPLACED AND THE FUSELAGE SKIN ADJACENT TO THE SOFT START RESISTOR WAS INSPECTED FOR OVERHEAT DAMAGE. NO DAMAGE WAS NOTED. THE WING TO FUSELAGE PANEL IS SCHEDULED TO BE REPLACED FOR COSMETIC REASONS. NO FAULT WAS NOTED WITH THE AIR GROUND WOW SYS AND IT IS SUSPECTED THAT THE INDICATION MAY BY BEEN AS A RESULT OF A CROSSWIND TAKEOFF AND IS UNRELATED TO THE HYD PRESSURE FAILURE. SEVERAL GEAR SWINGS WERE CONDUCTED WITH THE NEW PWR PACK AND ALL INDICATIONS ARE NORMAL.