Narrative:

The problem was dispatching a turbojet aircraft on a routine part 121 flight with an inoperative altitude alerter. The altitude alerter was inoperative and had been deferred in accordance with the MEL which states 'except where en route operations require its use, may be inoperative provided the autoplt with altitude hold is operative.' in this case it was clearly required for 'en route operations.' far 91.219 states, '...no person may operate a turbojet powered us-registered civil airplane unless that airplane is equipped with an approved altitude alerting system or device that is in operable condition...' except as provided by paragraph (D). Paragraph (D) states that the altitude alerter is not required for aircraft with an experimental certificate or for the purpose of ferrying the airplane under several different conditions, or for sales demonstration flts. Clearly none of these conditions applied to this flight. We were first told by dispatch that part 91 did not apply to us because we are a part 121 operator. Reaching an impasse with dispatch, we called the chief pilot. The chief pilot told us the altitude alerter was not required because the altitude hold portion of the autoplt was operative. The autoplt did not have an altitude arm and capture feature, it was strictly altitude hold to be engaged when reaching the desired altitude. The captain was directed by the chief pilot to take the flight and so we departed. I believe we violated far 91.219. There are training issues here, pressure from supervisors and other human factors that lead people to the conclusion they want, not necessarily the correct conclusion. This required an increase in pilot workload to compensate for the inoperative altitude alerter.

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Original NASA ASRS Text

Title: B727 FLT CREW QUESTIONS OPERATING THE ACFT WITHOUT AN OPERABLE ALT ALERTER VICE AN AUTOPLT ALT HOLD FUNCTION.

Narrative: THE PROB WAS DISPATCHING A TURBOJET ACFT ON A ROUTINE PART 121 FLT WITH AN INOP ALT ALERTER. THE ALT ALERTER WAS INOP AND HAD BEEN DEFERRED IN ACCORDANCE WITH THE MEL WHICH STATES 'EXCEPT WHERE ENRTE OPS REQUIRE ITS USE, MAY BE INOP PROVIDED THE AUTOPLT WITH ALT HOLD IS OPERATIVE.' IN THIS CASE IT WAS CLRLY REQUIRED FOR 'ENRTE OPS.' FAR 91.219 STATES, '...NO PERSON MAY OPERATE A TURBOJET POWERED US-REGISTERED CIVIL AIRPLANE UNLESS THAT AIRPLANE IS EQUIPPED WITH AN APPROVED ALT ALERTING SYS OR DEVICE THAT IS IN OPERABLE CONDITION...' EXCEPT AS PROVIDED BY PARAGRAPH (D). PARAGRAPH (D) STATES THAT THE ALT ALERTER IS NOT REQUIRED FOR ACFT WITH AN EXPERIMENTAL CERTIFICATE OR FOR THE PURPOSE OF FERRYING THE AIRPLANE UNDER SEVERAL DIFFERENT CONDITIONS, OR FOR SALES DEMONSTRATION FLTS. CLRLY NONE OF THESE CONDITIONS APPLIED TO THIS FLT. WE WERE FIRST TOLD BY DISPATCH THAT PART 91 DID NOT APPLY TO US BECAUSE WE ARE A PART 121 OPERATOR. REACHING AN IMPASSE WITH DISPATCH, WE CALLED THE CHIEF PLT. THE CHIEF PLT TOLD US THE ALT ALERTER WAS NOT REQUIRED BECAUSE THE ALT HOLD PORTION OF THE AUTOPLT WAS OPERATIVE. THE AUTOPLT DID NOT HAVE AN ALT ARM AND CAPTURE FEATURE, IT WAS STRICTLY ALT HOLD TO BE ENGAGED WHEN REACHING THE DESIRED ALT. THE CAPT WAS DIRECTED BY THE CHIEF PLT TO TAKE THE FLT AND SO WE DEPARTED. I BELIEVE WE VIOLATED FAR 91.219. THERE ARE TRAINING ISSUES HERE, PRESSURE FROM SUPVRS AND OTHER HUMAN FACTORS THAT LEAD PEOPLE TO THE CONCLUSION THEY WANT, NOT NECESSARILY THE CORRECT CONCLUSION. THIS REQUIRED AN INCREASE IN PLT WORKLOAD TO COMPENSATE FOR THE INOP ALT ALERTER.

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.