Narrative:

I preflted my small transport aircraft at ketchikan international airport dock and warmed it up. While warming this aircraft, I observed that I had 24 gallons in my front tank and 12 gallons in my center tank. I took off for ketchikan air harbor dock on my front tank. After reaching the harbor dock I loaded my aircraft for a 15 min flight to metlakana harbor. Again, I took off on the front tank with 24 gallons. About halfway there I switched to my center tank which had 12 gallons to burn my existing fuel in that tank. About 5 mins later my low fuel pressure light went on and I proceeded to hand pump my wobble pump in attempts to build my fuel pressure. This did not work. I made radio call to my company and informed them of the problem and my location. At that point, I checked again to see if I had fuel. My center tank was still showing 12 gallons. At this point I had to make a decision to continue trouble-shooting the problem or prepare for a downwind landing in open water with 3 people aboard. After the landing, I again tried to determine the cause of the problem. I got out on the floats and checked the aircraft. At that point I attempted a restart on the front tank. The engine started and I continued to metlakana to drop off my 3 passenger. I flew back to ketchikan alone and when I returned the center tank was indicating empty. After talking with several pilots and the mechanic, I was informed that these types of tank gauges have been known to stick.

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Original NASA ASRS Text

Title: SUSPECTING LOW FUEL, SMT FLOAT PLANE LANDS ON OPEN WATER TO INVESTIGATE PROB.

Narrative: I PREFLTED MY SMT ACFT AT KETCHIKAN INTL ARPT DOCK AND WARMED IT UP. WHILE WARMING THIS ACFT, I OBSERVED THAT I HAD 24 GALLONS IN MY FRONT TANK AND 12 GALLONS IN MY CTR TANK. I TOOK OFF FOR KETCHIKAN AIR HARBOR DOCK ON MY FRONT TANK. AFTER REACHING THE HARBOR DOCK I LOADED MY ACFT FOR A 15 MIN FLT TO METLAKANA HARBOR. AGAIN, I TOOK OFF ON THE FRONT TANK WITH 24 GALLONS. ABOUT HALFWAY THERE I SWITCHED TO MY CTR TANK WHICH HAD 12 GALLONS TO BURN MY EXISTING FUEL IN THAT TANK. ABOUT 5 MINS LATER MY LOW FUEL PRESSURE LIGHT WENT ON AND I PROCEEDED TO HAND PUMP MY WOBBLE PUMP IN ATTEMPTS TO BUILD MY FUEL PRESSURE. THIS DID NOT WORK. I MADE RADIO CALL TO MY COMPANY AND INFORMED THEM OF THE PROB AND MY LOCATION. AT THAT POINT, I CHKED AGAIN TO SEE IF I HAD FUEL. MY CTR TANK WAS STILL SHOWING 12 GALLONS. AT THIS POINT I HAD TO MAKE A DECISION TO CONTINUE TROUBLE-SHOOTING THE PROB OR PREPARE FOR A DOWNWIND LNDG IN OPEN WATER WITH 3 PEOPLE ABOARD. AFTER THE LNDG, I AGAIN TRIED TO DETERMINE THE CAUSE OF THE PROB. I GOT OUT ON THE FLOATS AND CHKED THE ACFT. AT THAT POINT I ATTEMPTED A RESTART ON THE FRONT TANK. THE ENG STARTED AND I CONTINUED TO METLAKANA TO DROP OFF MY 3 PAX. I FLEW BACK TO KETCHIKAN ALONE AND WHEN I RETURNED THE CTR TANK WAS INDICATING EMPTY. AFTER TALKING WITH SEVERAL PLTS AND THE MECH, I WAS INFORMED THAT THESE TYPES OF TANK GAUGES HAVE BEEN KNOWN TO STICK.

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.