Pilot of an small transport twin returned and landed after observing fuel leaking from a fuel tank.

Attributes
ACN	292343
Time
Date	199412
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : fll
State Reference	FL
Altitude	agl bound lower : 0 agl bound upper : 500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : fll
Operator	common carrier : air taxi
Make Model Name	Cessna 402/402C/B379 Businessliner/Utiliner
Operating Under FAR Part	Part 135
Flight Phase	climbout : initial climbout : takeoff other
Flight Plan	IFR
Person 1
Affiliation	company : air taxi
Function	flight crew : single pilot
Qualification	pilot : atp pilot : cfi pilot : commercial pilot : instrument
Experience	flight time last 90 days : 120 flight time total : 7800 flight time type : 4200
ASRS Report	292343
Person 2
Affiliation	company : air carrier
Function	other personnel other
Qualification	other other : other
Events
Anomaly	aircraft equipment problem : less severe other anomaly other
Independent Detector	other flight crewa
Resolutory Action	other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

I had made 1 round trip after which I only needed the fuel tanks about quarter full. On preparation for next leg, I ordered the fuel topped off. I was present during fueling, supervising the loading of aircraft. The fueler did not indicate to me that there was anything wrong with the caps. Before taxi, I visually inspected the fuel caps, that they were on and locked down. Taxi was normal. On takeoff, out of the corner of my eye I saw something streaming back from the left side of the aircraft. I looked and saw that the cap was loose and fuel was escaping in a fine mist. I immediately requested to return to the airport. Landing was normal. Since the fuel was blowing away from the engines, I did not request assistance. On return to the gate, I first checked to see that the cap had not just been locked improperly. Unfortunately, there appeared to be a bad seal. I disembarked the passenger , went over to the maintenance hangar and received a new cap which fit tightly. I returned to the gate and spoke with the passenger on what had happened. They seemed satisfied with the new cap. We departed and the rest of the flight was normal. Maintenance was advised of the problem during the situation, gave me instructions, and attended the problem on my return.

Original NASA ASRS Text

Title: PLT OF AN SMT TWIN RETURNED AND LANDED AFTER OBSERVING FUEL LEAKING FROM A FUEL TANK.

Narrative: I HAD MADE 1 ROUND TRIP AFTER WHICH I ONLY NEEDED THE FUEL TANKS ABOUT QUARTER FULL. ON PREPARATION FOR NEXT LEG, I ORDERED THE FUEL TOPPED OFF. I WAS PRESENT DURING FUELING, SUPERVISING THE LOADING OF ACFT. THE FUELER DID NOT INDICATE TO ME THAT THERE WAS ANYTHING WRONG WITH THE CAPS. BEFORE TAXI, I VISUALLY INSPECTED THE FUEL CAPS, THAT THEY WERE ON AND LOCKED DOWN. TAXI WAS NORMAL. ON TKOF, OUT OF THE CORNER OF MY EYE I SAW SOMETHING STREAMING BACK FROM THE L SIDE OF THE ACFT. I LOOKED AND SAW THAT THE CAP WAS LOOSE AND FUEL WAS ESCAPING IN A FINE MIST. I IMMEDIATELY REQUESTED TO RETURN TO THE ARPT. LNDG WAS NORMAL. SINCE THE FUEL WAS BLOWING AWAY FROM THE ENGS, I DID NOT REQUEST ASSISTANCE. ON RETURN TO THE GATE, I FIRST CHKED TO SEE THAT THE CAP HAD NOT JUST BEEN LOCKED IMPROPERLY. UNFORTUNATELY, THERE APPEARED TO BE A BAD SEAL. I DISEMBARKED THE PAX , WENT OVER TO THE MAINT HANGAR AND RECEIVED A NEW CAP WHICH FIT TIGHTLY. I RETURNED TO THE GATE AND SPOKE WITH THE PAX ON WHAT HAD HAPPENED. THEY SEEMED SATISFIED WITH THE NEW CAP. WE DEPARTED AND THE REST OF THE FLT WAS NORMAL. MAINT WAS ADVISED OF THE PROB DURING THE SIT, GAVE ME INSTRUCTIONS, AND ATTENDED THE PROB ON MY RETURN.

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.