Narrative:

I was preflting my cessna cardinal for a 4.5 hour flight from the west coast to boise. During the refueling, I was interrupted by my passenger (wife) to assist her loading luggage. I completed refueling by collapsing the ladder and securing the fuel pumps. 1.5 hours into the flight, I was at 10000 ft over the cascades mountains when my wife noticed that the right fuel gauge was indicating 1/4 tank, and the left fuel gauge was indicating 1/2 tank. To my horror, I realized that I had not replaced the fuel cap after loading the baggage, and that I probably did not have enough fuel to land at the nearest community airport east of the cascades. I pushed the emergency GPS button for the nearest airport to learn that a 1400 ft grass air strip was under me in a narrow mountain pass. I immediately began a descent, however, I was unable to reach air radio due to the surrounding high terrain. The landing was bumpy, but uneventful. As I stepped out of the aircraft, I was soaked with fuel draining off the wing. To my relief, the fuel cap was still hanging from its chain. I measured the remaining fuel, replaced the fuel cap and continued my flight to the next community airport. Contributing factors: I allowed myself to be distraction from a critical preflight function (refueling) and I did not complete a final preflight check of the fuel caps. I did not monitor engine and fuel gauges during flight.

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Original NASA ASRS Text

Title: A C177 PLT BECOMING DISTR WHILE FUELING HIS ACFT, NEGLECTED TO REPLACE THE FUEL CAP, RESULTING IN AN EMER LNDG AT THE NEAREST ARPT.

Narrative: I WAS PREFLTING MY CESSNA CARDINAL FOR A 4.5 HR FLT FROM THE WEST COAST TO BOISE. DURING THE REFUELING, I WAS INTERRUPTED BY MY PAX (WIFE) TO ASSIST HER LOADING LUGGAGE. I COMPLETED REFUELING BY COLLAPSING THE LADDER AND SECURING THE FUEL PUMPS. 1.5 HRS INTO THE FLT, I WAS AT 10000 FT OVER THE CASCADES MOUNTAINS WHEN MY WIFE NOTICED THAT THE R FUEL GAUGE WAS INDICATING 1/4 TANK, AND THE L FUEL GAUGE WAS INDICATING 1/2 TANK. TO MY HORROR, I REALIZED THAT I HAD NOT REPLACED THE FUEL CAP AFTER LOADING THE BAGGAGE, AND THAT I PROBABLY DID NOT HAVE ENOUGH FUEL TO LAND AT THE NEAREST COMMUNITY ARPT E OF THE CASCADES. I PUSHED THE EMER GPS BUTTON FOR THE NEAREST ARPT TO LEARN THAT A 1400 FT GRASS AIR STRIP WAS UNDER ME IN A NARROW MOUNTAIN PASS. I IMMEDIATELY BEGAN A DSCNT, HOWEVER, I WAS UNABLE TO REACH AIR RADIO DUE TO THE SURROUNDING HIGH TERRAIN. THE LNDG WAS BUMPY, BUT UNEVENTFUL. AS I STEPPED OUT OF THE ACFT, I WAS SOAKED WITH FUEL DRAINING OFF THE WING. TO MY RELIEF, THE FUEL CAP WAS STILL HANGING FROM ITS CHAIN. I MEASURED THE REMAINING FUEL, REPLACED THE FUEL CAP AND CONTINUED MY FLT TO THE NEXT COMMUNITY ARPT. CONTRIBUTING FACTORS: I ALLOWED MYSELF TO BE DISTR FROM A CRITICAL PREFLT FUNCTION (REFUELING) AND I DID NOT COMPLETE A FINAL PREFLT CHK OF THE FUEL CAPS. I DID NOT MONITOR ENG AND FUEL GAUGES DURING FLT.

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.