Narrative:

This aircraft is a C150-M with long-range tanks installed. The aircraft had not been flown for the preceding 2 months and was stored outdoors. A thorough preflight was completed. The wing tanks were 3/4 full and drained twice with a common cylinder type fuel tester. The gascolator was fully drained and checked for water and contaminates. No significant water or contaminates were found. The engine was easily hand propped to a start due to a low battery. Total engine ground run time was approximately 40 mins at 1200-1700 RPM with normal engine indications. A takeoff was completed on runway 22L at hnl. Approximately 4 NM from departure (over nps airport) hnl departure control indicated and confirmed the aircraft's transponder inoperative and requested a return to hnl. This was complied with and completed. Taxiing to the hangar area the aircraft's engine quit and would not restart. The aircraft was manually pushed to the hangar area. Nine tenths (.9) was the total time on the hobbs meter since engine start, approximately two tenths (.2) of which were in-flight. Examination of the fuel tanks, fuel line, gascolator and carburetor fuel bowl revealed water in all areas. After draining, the aircraft restarted easily with normal battery power. Although special attention was given to check the fuel system for water, had an accident occurred pilot error (due to an improper preflight) would be considered the major contributing factor. Reflecting on this incident, I have speculated this conclusion: with over 6000 hours on the airframe (and a damage history to the left wing) one or both fuel tanks have become warped or wavy allowing water to collect at points other than the fuel drain. This allowed the water to remain undetected during a normal preflight, a 40 min ground run, and in-flight. It is noteworthy that an extended slip was used during landing due to moderate right xwinds. It was after this slip the engine quit. Other contributing factors could be: worn seals on one or both gas caps, aircraft stored with less than full tanks, and, although it is not mentioned in the cessna operating handbook, rocking the aircraft wings during preflight to move any distributed water to the fuel drain.

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Original NASA ASRS Text

Title: C150 HAD WATER IN THE FUEL SYS THAT COULD NOT BE DETECTED DURING A NORMAL PREFLT INSPECTION. RPTR SAYS, RIGHTLY, THAT AN ACFT THAT HAS NOT FLOWN FOR AN EXTENDED PERIOD SHOULD BE APCHED WITH CAUTION. ENG QUIT WHILE TAXIING AFTER LNDG. A WRINKLE IN A FUEL BLADDER COULD TRAPS WATER THAT WOULD NOT APPEAR DURING THE PREFLT.

Narrative: THIS ACFT IS A C150-M WITH LONG-RANGE TANKS INSTALLED. THE ACFT HAD NOT BEEN FLOWN FOR THE PRECEDING 2 MONTHS AND WAS STORED OUTDOORS. A THOROUGH PREFLT WAS COMPLETED. THE WING TANKS WERE 3/4 FULL AND DRAINED TWICE WITH A COMMON CYLINDER TYPE FUEL TESTER. THE GASCOLATOR WAS FULLY DRAINED AND CHKED FOR WATER AND CONTAMINATES. NO SIGNIFICANT WATER OR CONTAMINATES WERE FOUND. THE ENG WAS EASILY HAND PROPPED TO A START DUE TO A LOW BATTERY. TOTAL ENG GND RUN TIME WAS APPROX 40 MINS AT 1200-1700 RPM WITH NORMAL ENG INDICATIONS. A TKOF WAS COMPLETED ON RWY 22L AT HNL. APPROX 4 NM FROM DEP (OVER NPS ARPT) HNL DEP CTL INDICATED AND CONFIRMED THE ACFT'S XPONDER INOP AND REQUESTED A RETURN TO HNL. THIS WAS COMPLIED WITH AND COMPLETED. TAXIING TO THE HANGAR AREA THE ACFT'S ENG QUIT AND WOULD NOT RESTART. THE ACFT WAS MANUALLY PUSHED TO THE HANGAR AREA. NINE TENTHS (.9) WAS THE TOTAL TIME ON THE HOBBS METER SINCE ENG START, APPROX TWO TENTHS (.2) OF WHICH WERE INFLT. EXAMINATION OF THE FUEL TANKS, FUEL LINE, GASCOLATOR AND CARB FUEL BOWL REVEALED WATER IN ALL AREAS. AFTER DRAINING, THE ACFT RESTARTED EASILY WITH NORMAL BATTERY PWR. ALTHOUGH SPECIAL ATTN WAS GIVEN TO CHK THE FUEL SYS FOR WATER, HAD AN ACCIDENT OCCURRED PLT ERROR (DUE TO AN IMPROPER PREFLT) WOULD BE CONSIDERED THE MAJOR CONTRIBUTING FACTOR. REFLECTING ON THIS INCIDENT, I HAVE SPECULATED THIS CONCLUSION: WITH OVER 6000 HRS ON THE AIRFRAME (AND A DAMAGE HISTORY TO THE L WING) ONE OR BOTH FUEL TANKS HAVE BECOME WARPED OR WAVY ALLOWING WATER TO COLLECT AT POINTS OTHER THAN THE FUEL DRAIN. THIS ALLOWED THE WATER TO REMAIN UNDETECTED DURING A NORMAL PREFLT, A 40 MIN GND RUN, AND INFLT. IT IS NOTEWORTHY THAT AN EXTENDED SLIP WAS USED DURING LNDG DUE TO MODERATE R XWINDS. IT WAS AFTER THIS SLIP THE ENG QUIT. OTHER CONTRIBUTING FACTORS COULD BE: WORN SEALS ON ONE OR BOTH GAS CAPS, ACFT STORED WITH LESS THAN FULL TANKS, AND, ALTHOUGH IT IS NOT MENTIONED IN THE CESSNA OPERATING HANDBOOK, ROCKING THE ACFT WINGS DURING PREFLT TO MOVE ANY DISTRIBUTED WATER TO THE FUEL DRAIN.

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.