B190 crew had a main fuel tank cap come off the aircraft in-flight.

Attributes
ACN	583153
Time
Date	200305
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : mhk.airport
State Reference	KS
Altitude	agl single value : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : zzz.tower
Operator	common carrier : air taxi
Make Model Name	Beech 1900
Operating Under FAR Part	Part 121
Flight Phase	landing : roll
Flight Plan	IFR
Person 1
Affiliation	company : air taxi
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 3200 flight time type : 2000
ASRS Report	583153
Person 2
Affiliation	company : air taxi
Function	flight crew : first officer
Events
Anomaly	aircraft equipment problem : critical maintenance problem : improper maintenance other anomaly other
Independent Detector	other flight crewa other flight crewb
Resolutory Action	none taken : detected after the fact other
Consequence	other
Factors
Maintenance	performance deficiency : inspection performance deficiency : testing
Supplementary
Problem Areas	Maintenance Human Performance Company Aircraft
Primary Problem	Company

Narrative:

On may/fri/03, my first officer noticed a fuel imbal on his preflight. The indicators did not match. He told me of the problem and I asked him to have the fueler fill the shorted side (left main). The fueler tried to fill the left side and it was full. It turns out that the fuel quantity indicator was inoperative. I wrote up the left fuel quantity indicator and placarded the indicator. My first officer paid attention to the fueler securing the fuel cap on the left main. Part of our before start checklist is to ensure propellers are clear and fuel caps are secure. We accomplished that successfully. We landed at our destination and my first officer found that the left main fuel cap was missing on his postflt. We called maintenance control and arranged a mechanic to take the left auxiliary tank cap and put it on the left main tank and speed tape the left auxiliary tank (which was empty). Then we ferried the aircraft back to the originating airport to get a new cap from line maintenance. I felt my first officer and I were prudent about the way we handled the fuel indicator, as well as we were prudent to ensure the cap was secure. This situation illustrates no matter the level of prudence there is still room for error or failure. Thorough postflts are just as essential as to a thorough preflight. There is always room for something to go wrong.

Original NASA ASRS Text

Title: B190 CREW HAD A MAIN FUEL TANK CAP COME OFF THE ACFT INFLT.

Narrative: ON MAY/FRI/03, MY FO NOTICED A FUEL IMBAL ON HIS PREFLT. THE INDICATORS DID NOT MATCH. HE TOLD ME OF THE PROB AND I ASKED HIM TO HAVE THE FUELER FILL THE SHORTED SIDE (L MAIN). THE FUELER TRIED TO FILL THE L SIDE AND IT WAS FULL. IT TURNS OUT THAT THE FUEL QUANTITY INDICATOR WAS INOP. I WROTE UP THE L FUEL QUANTITY INDICATOR AND PLACARDED THE INDICATOR. MY FO PAID ATTN TO THE FUELER SECURING THE FUEL CAP ON THE L MAIN. PART OF OUR BEFORE START CHKLIST IS TO ENSURE PROPS ARE CLR AND FUEL CAPS ARE SECURE. WE ACCOMPLISHED THAT SUCCESSFULLY. WE LANDED AT OUR DEST AND MY FO FOUND THAT THE L MAIN FUEL CAP WAS MISSING ON HIS POSTFLT. WE CALLED MAINT CTL AND ARRANGED A MECH TO TAKE THE L AUX TANK CAP AND PUT IT ON THE L MAIN TANK AND SPD TAPE THE L AUX TANK (WHICH WAS EMPTY). THEN WE FERRIED THE ACFT BACK TO THE ORIGINATING ARPT TO GET A NEW CAP FROM LINE MAINT. I FELT MY FO AND I WERE PRUDENT ABOUT THE WAY WE HANDLED THE FUEL INDICATOR, AS WELL AS WE WERE PRUDENT TO ENSURE THE CAP WAS SECURE. THIS SIT ILLUSTRATES NO MATTER THE LEVEL OF PRUDENCE THERE IS STILL ROOM FOR ERROR OR FAILURE. THOROUGH POSTFLTS ARE JUST AS ESSENTIAL AS TO A THOROUGH PREFLT. THERE IS ALWAYS ROOM FOR SOMETHING TO GO WRONG.

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.