Narrative:

Flight was dispatched from ZZZ to ZZZ2 utilizing overwater portion of flight plan. This portion of flight plan required life-rafts, life-vests, and various other overwater equipment, all of which were on board and allowed for. However, the aircraft's APU was deferred and the MEL stipulated that no 'extended operations' be conducted. The route we used was overwater but class 1 navigation approved and there was some debate as to whether it constituted 'extended operations.' whilst the terms extended overwater operations and overwater operations are defined by far, the MEL is ambiguous as to whether 'extended operations' pertains to extended overwater operations or outside class 1 navigation operations (ie, class 2). The MEL description should more closely or match exactly or refer directly to the respective far definition to ensure there is no room for error or misinterp on this matter. In addition, the fact that ATC has constant radar coverage over this route whilst it is outside VOR high service volume but considered class 1 by the FAA makes it further complicating.

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Original NASA ASRS Text

Title: AN MD82 WAS DISPATCHED IN NON COMPLIANCE WITH AN APU DEFERRED AS INOP. ACFT DISPATCHED ON OVERWATER ROUTING.

Narrative: FLT WAS DISPATCHED FROM ZZZ TO ZZZ2 UTILIZING OVERWATER PORTION OF FLT PLAN. THIS PORTION OF FLT PLAN REQUIRED LIFE-RAFTS, LIFE-VESTS, AND VARIOUS OTHER OVERWATER EQUIP, ALL OF WHICH WERE ON BOARD AND ALLOWED FOR. HOWEVER, THE ACFT'S APU WAS DEFERRED AND THE MEL STIPULATED THAT NO 'EXTENDED OPS' BE CONDUCTED. THE RTE WE USED WAS OVERWATER BUT CLASS 1 NAV APPROVED AND THERE WAS SOME DEBATE AS TO WHETHER IT CONSTITUTED 'EXTENDED OPS.' WHILST THE TERMS EXTENDED OVERWATER OPS AND OVERWATER OPS ARE DEFINED BY FAR, THE MEL IS AMBIGUOUS AS TO WHETHER 'EXTENDED OPS' PERTAINS TO EXTENDED OVERWATER OPS OR OUTSIDE CLASS 1 NAV OPS (IE, CLASS 2). THE MEL DESCRIPTION SHOULD MORE CLOSELY OR MATCH EXACTLY OR REFER DIRECTLY TO THE RESPECTIVE FAR DEFINITION TO ENSURE THERE IS NO ROOM FOR ERROR OR MISINTERP ON THIS MATTER. IN ADDITION, THE FACT THAT ATC HAS CONSTANT RADAR COVERAGE OVER THIS RTE WHILST IT IS OUTSIDE VOR HIGH SVC VOLUME BUT CONSIDERED CLASS 1 BY THE FAA MAKES IT FURTHER COMPLICATING.

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.