Narrative:

I taxied the small aircraft out for takeoff after its 100 hour inspection. During the runup I realized the vacuum pressure was too high, I got the warning light. I decided to taxi back to have the mechanics look at it. I decided to turn the airplane around on the taxiway. The taxiway was reasonably narrow and I realized the aircraft would need to go onto the grass momentarily to complete the turn. As I taxied slowly onto the grass, the nosewheel sunk in, causing the propeller to contact the grass, throwing dirt all over the place. The propeller didn't stop, in fact I thought initially that I had just blown dirt back, but when I stopped the engine I realized that it had hit. The propeller was ruined, the last 2' or so of each tip was mangled. A contributing factor was the problem with the vacuum system. The FBO should have tested the airplane before putting it back on line. I could have avoided the whole problem by taxiing out onto the runway and then back to the taxiway instead of turning in a narrow space, but I didn't want to tie up the runway as airplanes were in the pattern. (See what happens to nice guys?) besides, in probably 90% of the airports in america, airplanes are tied down on the grass. I've operated on grass many times. The FAA requires the demonstration of soft field landing skills, implying that it's a standard procedure to operate on a soft surface. It just didn't occur to me that the ground would give way like it did.

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Original NASA ASRS Text

Title: GA SMA TAXIED ONTO GRASS AREA AND PROPELLER WAS DAMAGED WHEN NOSE WHEEL SUNK IN THE SOFT TURF.

Narrative: I TAXIED THE SMA OUT FOR TKOF AFTER ITS 100 HR INSPECTION. DURING THE RUNUP I REALIZED THE VACUUM PRESSURE WAS TOO HIGH, I GOT THE WARNING LIGHT. I DECIDED TO TAXI BACK TO HAVE THE MECHS LOOK AT IT. I DECIDED TO TURN THE AIRPLANE AROUND ON THE TXWY. THE TXWY WAS REASONABLY NARROW AND I REALIZED THE ACFT WOULD NEED TO GO ONTO THE GRASS MOMENTARILY TO COMPLETE THE TURN. AS I TAXIED SLOWLY ONTO THE GRASS, THE NOSEWHEEL SUNK IN, CAUSING THE PROP TO CONTACT THE GRASS, THROWING DIRT ALL OVER THE PLACE. THE PROP DIDN'T STOP, IN FACT I THOUGHT INITIALLY THAT I HAD JUST BLOWN DIRT BACK, BUT WHEN I STOPPED THE ENG I REALIZED THAT IT HAD HIT. THE PROP WAS RUINED, THE LAST 2' OR SO OF EACH TIP WAS MANGLED. A CONTRIBUTING FACTOR WAS THE PROB WITH THE VACUUM SYS. THE FBO SHOULD HAVE TESTED THE AIRPLANE BEFORE PUTTING IT BACK ON LINE. I COULD HAVE AVOIDED THE WHOLE PROB BY TAXIING OUT ONTO THE RWY AND THEN BACK TO THE TXWY INSTEAD OF TURNING IN A NARROW SPACE, BUT I DIDN'T WANT TO TIE UP THE RWY AS AIRPLANES WERE IN THE PATTERN. (SEE WHAT HAPPENS TO NICE GUYS?) BESIDES, IN PROBABLY 90% OF THE ARPTS IN AMERICA, AIRPLANES ARE TIED DOWN ON THE GRASS. I'VE OPERATED ON GRASS MANY TIMES. THE FAA REQUIRES THE DEMONSTRATION OF SOFT FIELD LNDG SKILLS, IMPLYING THAT IT'S A STANDARD PROC TO OPERATE ON A SOFT SURFACE. IT JUST DIDN'T OCCUR TO ME THAT THE GND WOULD GIVE WAY LIKE IT DID.

Data retrieved from NASA's ASRS site as of August 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.