The cap for the alcohol water injection system was lost en route.

Attributes
ACN	284584
Time
Date	199409
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : bil
State Reference	MT
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 135
Flight Phase	ground : preflight
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : cfi pilot : commercial pilot : instrument pilot : atp
Experience	flight time last 90 days : 250 flight time total : 6000 flight time type : 3000
ASRS Report	284584
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	aircraft equipment problem : less severe non adherence : published procedure other anomaly other
Independent Detector	other other : unspecified
Resolutory Action	none taken : detected after the fact
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Prior to departure from billings, to helena requested of the ground agent that the awi (alcohol water injection) be brought up to 12 gallons. The agent completed the task, and an uneventful flight followed. Upon arrival in helena the alert flight crew noticed on their preflight that the awi tank filler cap was missing. Failure of the ground agent to reinstall the filled cap was the original cause for this problem. It is however the responsibility of the flight crew to determine that the procedure had been done correctly, and the filler cap had been replaced. It is imperative that the flight crew verify the proper completion of any aircraft servicing.

Original NASA ASRS Text

Title: THE CAP FOR THE ALCOHOL WATER INJECTION SYS WAS LOST ENRTE.

Narrative: PRIOR TO DEP FROM BILLINGS, TO HELENA REQUESTED OF THE GND AGENT THAT THE AWI (ALCOHOL WATER INJECTION) BE BROUGHT UP TO 12 GALLONS. THE AGENT COMPLETED THE TASK, AND AN UNEVENTFUL FLT FOLLOWED. UPON ARR IN HELENA THE ALERT FLC NOTICED ON THEIR PREFLT THAT THE AWI TANK FILLER CAP WAS MISSING. FAILURE OF THE GND AGENT TO REINSTALL THE FILLED CAP WAS THE ORIGINAL CAUSE FOR THIS PROB. IT IS HOWEVER THE RESPONSIBILITY OF THE FLC TO DETERMINE THAT THE PROC HAD BEEN DONE CORRECTLY, AND THE FILLER CAP HAD BEEN REPLACED. IT IS IMPERATIVE THAT THE FLC VERIFY THE PROPER COMPLETION OF ANY ACFT SVCING.

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.