Flight crew consulted MEL en route, and became uncertain regarding aircraft's airworthiness.

Attributes
ACN	315910
Time
Date	199509
Day	Fri
Local Time Of Day	0001 To 0600
Place
Locale Reference	airport : huf
State Reference	IN
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B727-200
Operating Under FAR Part	Part 121
Flight Phase	ground : preflight
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer pilot : cfi pilot : atp
Experience	flight time last 90 days : 150 flight time total : 8900 flight time type : 4235
ASRS Report	315910
Person 2
Affiliation	company : air carrier
Function	flight crew : second officer
Qualification	pilot : flight engineer pilot : atp
Experience	flight time last 90 days : 50 flight time total : 4000
ASRS Report	316444
Events
Anomaly	aircraft equipment problem : less severe other anomaly other
Independent Detector	other flight crewa other other : unspecified
Resolutory Action	none taken : detected after the fact other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	other

Narrative:

We were dispatched for a flight from huf to lax. Type aircraft was a cargo frame B727. The mechanic returned to the aircraft with the aircraft logbook. At this point the aircraft was loaded, the doors were closed, and the paperwork and checklists were completed. The mechanic handed me the logbook and informed me that one of the anti-collision beacons had been deferred. I took his word for it (without checking the MEL) and departed for huf. En route, while checking the MEL, I discovered that the aircraft could not have its anti- collision light deferred unless the aircraft was equipped with strobe lights. Aircraft was not equipped with strobe lights. On arrival in lax I contacted both maintenance and the chief pilot. Both assured me that the other anti-collision light (the one that was not deferred) was in fact a strobe light. The MEL is not clear on this, hence this report. Callback conversation with reporter revealed the following information: captain states that this report emanated from a false alarm. Confusion arose over the meanings of the terms 'strobe' versus 'beacon' light. The B727-200 is equipped with wingtip strobes and 2 red lights -- the one on top is a beacon, and a red flashing strobe is mounted on the belly. The upper beacon was inoperative, leaving the wingtip strobes and the belly operating, and therefore functioning as more than the minimum anti-collision system necessary for a legal flight. Reporter states that the many different interps and their disagreement added to the problem. Supplemental information from acn 316444: the logbook was not given to the crew by maintenance until 10 mins after departure time. The logbook had several write-ups concerning external aircraft lighting. It was understood by the crew that we could fly without a working upper rotating beacon at night since all other lights on the aircraft were operational. Upon arriving at the aircraft the next day in lax maintenance noted that we could not fly at night without an operational upper beacon. We rechked the MEL and discovered that on 'some' aircraft without anti-collision strobe lights this is true. We were on such an aircraft.

Original NASA ASRS Text

Title: FLC CONSULTED MEL ENRTE, AND BECAME UNCERTAIN REGARDING ACFT'S AIRWORTHINESS.

Narrative: WE WERE DISPATCHED FOR A FLT FROM HUF TO LAX. TYPE ACFT WAS A CARGO FRAME B727. THE MECH RETURNED TO THE ACFT WITH THE ACFT LOGBOOK. AT THIS POINT THE ACFT WAS LOADED, THE DOORS WERE CLOSED, AND THE PAPERWORK AND CHKLISTS WERE COMPLETED. THE MECH HANDED ME THE LOGBOOK AND INFORMED ME THAT ONE OF THE ANTI-COLLISION BEACONS HAD BEEN DEFERRED. I TOOK HIS WORD FOR IT (WITHOUT CHKING THE MEL) AND DEPARTED FOR HUF. ENRTE, WHILE CHKING THE MEL, I DISCOVERED THAT THE ACFT COULD NOT HAVE ITS ANTI- COLLISION LIGHT DEFERRED UNLESS THE ACFT WAS EQUIPPED WITH STROBE LIGHTS. ACFT WAS NOT EQUIPPED WITH STROBE LIGHTS. ON ARR IN LAX I CONTACTED BOTH MAINT AND THE CHIEF PLT. BOTH ASSURED ME THAT THE OTHER ANTI-COLLISION LIGHT (THE ONE THAT WAS NOT DEFERRED) WAS IN FACT A STROBE LIGHT. THE MEL IS NOT CLR ON THIS, HENCE THIS RPT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: CAPT STATES THAT THIS RPT EMANATED FROM A FALSE ALARM. CONFUSION AROSE OVER THE MEANINGS OF THE TERMS 'STROBE' VERSUS 'BEACON' LIGHT. THE B727-200 IS EQUIPPED WITH WINGTIP STROBES AND 2 RED LIGHTS -- THE ONE ON TOP IS A BEACON, AND A RED FLASHING STROBE IS MOUNTED ON THE BELLY. THE UPPER BEACON WAS INOP, LEAVING THE WINGTIP STROBES AND THE BELLY OPERATING, AND THEREFORE FUNCTIONING AS MORE THAN THE MINIMUM ANTI-COLLISION SYS NECESSARY FOR A LEGAL FLT. RPTR STATES THAT THE MANY DIFFERENT INTERPS AND THEIR DISAGREEMENT ADDED TO THE PROB. SUPPLEMENTAL INFO FROM ACN 316444: THE LOGBOOK WAS NOT GIVEN TO THE CREW BY MAINT UNTIL 10 MINS AFTER DEP TIME. THE LOGBOOK HAD SEVERAL WRITE-UPS CONCERNING EXTERNAL ACFT LIGHTING. IT WAS UNDERSTOOD BY THE CREW THAT WE COULD FLY WITHOUT A WORKING UPPER ROTATING BEACON AT NIGHT SINCE ALL OTHER LIGHTS ON THE ACFT WERE OPERATIONAL. UPON ARRIVING AT THE ACFT THE NEXT DAY IN LAX MAINT NOTED THAT WE COULD NOT FLY AT NIGHT WITHOUT AN OPERATIONAL UPPER BEACON. WE RECHKED THE MEL AND DISCOVERED THAT ON 'SOME' ACFT WITHOUT ANTI-COLLISION STROBE LIGHTS THIS IS TRUE. WE WERE ON SUCH AN ACFT.

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.