Narrative:

After a normal preflight, taxi and takeoff climbing through 3000 ft, the aircraft cabin would not pressurize. After several attempts of trying to reset the bleed valves, with the pressurization controller, the cabin was unable to be pressurized. I concluded that the automatic psi controller was not operating normally. I was then unable to fly back to anchorage at my flight plan cruising altitude, as a result of no pressurization. I opted to take a lower route, which in turn would use more fuel. I then landed in aniak to put on more fuel. The passenger were deplaned, the plane was refueled. I called operations letting them know of my situation. The passenger were reboarded. After a normal preflight, taxi and takeoff, the flight continued to anchorage at a lower altitude and, once reaching anchorage, landed safely. After landing at anchorage, I noticed that one of the blades on the right propeller had sucked up a rock on takeoff at ksm. The rock, after nicking the propeller, struck the belly of the aircraft causing a small hole. I did not see the hole on preflight at aniak. It was in a difficult place to see. After further examination from maintenance, the hole was determined to be the probable cause, for not allowing the aircraft to be pressurized.

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Original NASA ASRS Text

Title: AN ACR LTT NICKED ITS PROP AND HOLED ITS FUSELAGE WITH A ROCK.

Narrative: AFTER A NORMAL PREFLT, TAXI AND TKOF CLBING THROUGH 3000 FT, THE ACFT CABIN WOULD NOT PRESSURIZE. AFTER SEVERAL ATTEMPTS OF TRYING TO RESET THE BLEED VALVES, WITH THE PRESSURIZATION CTLR, THE CABIN WAS UNABLE TO BE PRESSURIZED. I CONCLUDED THAT THE AUTOMATIC PSI CTLR WAS NOT OPERATING NORMALLY. I WAS THEN UNABLE TO FLY BACK TO ANCHORAGE AT MY FLT PLAN CRUISING ALT, AS A RESULT OF NO PRESSURIZATION. I OPTED TO TAKE A LOWER RTE, WHICH IN TURN WOULD USE MORE FUEL. I THEN LANDED IN ANIAK TO PUT ON MORE FUEL. THE PAX WERE DEPLANED, THE PLANE WAS REFUELED. I CALLED OPS LETTING THEM KNOW OF MY SIT. THE PAX WERE REBOARDED. AFTER A NORMAL PREFLT, TAXI AND TKOF, THE FLT CONTINUED TO ANCHORAGE AT A LOWER ALT AND, ONCE REACHING ANCHORAGE, LANDED SAFELY. AFTER LNDG AT ANCHORAGE, I NOTICED THAT ONE OF THE BLADES ON THE R PROP HAD SUCKED UP A ROCK ON TKOF AT KSM. THE ROCK, AFTER NICKING THE PROP, STRUCK THE BELLY OF THE ACFT CAUSING A SMALL HOLE. I DID NOT SEE THE HOLE ON PREFLT AT ANIAK. IT WAS IN A DIFFICULT PLACE TO SEE. AFTER FURTHER EXAMINATION FROM MAINT, THE HOLE WAS DETERMINED TO BE THE PROBABLE CAUSE, FOR NOT ALLOWING THE ACFT TO BE PRESSURIZED.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.