Boeing Bulletins

FMC-10 : FMC Assumed Temperature Derate Anomaly

2 April 2001

Effectivity

Please refer to source document.

Reason

This bulletin provides information for flight crews regarding FMC anomaly.

Information in this bulletin is recommended by The Boeing Company, but may not be FAA approved at the time of writing. In the event of conflict with the FAA approved Airplane Flight Manual (AFM), the AFM shall supersede. The Boeing Company regards the information or procedures described herein as having a direct or indirect bearing on the safe operation of this model airplane.

Background Information

Re-entering the previously entered assumed temperature on the CDU TAKEOFF REF page may not be accepted by the FMC. Assumed temperature entries selected via the Thrust Mode Select Panel (TMSP) are accepted by the FMC.

This anomaly appears on airplanes with the PEGASUS FMC installed. The PEGASUS FMC can be identified by a VNAV Mode Key on the CDU.

Operating Instructions

Enter assumed temperature using the TMSP if the FMC assumed temperature entry is not accepted.

Administrative Information (Extract)

This anomaly will be corrected by Boeing Service Bulletin 757-34-0181 scheduled to be available April 1, 1999. This Operations Manual Bulletin will be canceled after Boeing is notified that all affected airplanes in the operators fleet have been modified.