EASA SIB SAFO23004
Erroneous Maximum Takeoff Weight Calculation from Boeing Performance Engineer's Tool Reporters
Summary
The document titled 'Erroneous Maximum Takeoff Weight Calculation from Boeing Performance Engineer's Tool Reporters' is a Safety Alert for Operators (SAFO 23004) issued by the FAA. It addresses an issue affecting Boeing airplane models 737-200, 737-300, 737-400, 737-500, 747-200, 747-300, 747-400, 757-200, 767-200, and 767-300, where the Boeing Performance Engineer's Tool (PET) Reporters may calculate incorrect Maximum Takeoff Weight (MTOW) values. This error impacts takeoff performance calculations, particularly when using the Improved Climb feature, potentially leading to safety risks such as runway overruns or insufficient climb performance.
What Changed
This SAFO introduces awareness of the erroneous MTOW calculation issue occurring in PET Reporters versions 3.4 through 4.4 when used with Improved Climb and older Boeing Takeoff Performance Subroutine (BTOPS) databases that do not support Fixed Improved Climb. It clarifies that the error does not occur with PET Reporters without Improved Climb, with BTOPS databases supporting Fixed Improved Climb, or with Boeing Takeoff Module (BTM) databases. The document recommends updating PET to version 4.5 to resolve the issue.
Why It Matters
This issue is critical for aviation professionals because incorrect MTOW calculations can lead to unsafe takeoff performance parameters, increasing the risk of runway overruns during rejected takeoffs, failure to rotate properly, or inadequate climb performance for obstacle clearance. Operators, maintenance, and compliance teams must ensure accurate performance data to maintain flight safety and regulatory compliance.
What To Do
Affected operators should update their Boeing Performance Engineer's Tool to version 4.5 as recommended by Boeing MOM-MOM-23-0179-01B. They must delete any Runway Takeoff Weight charts generated with older PET versions and regenerate these charts using PET version 4.5. No specific compliance deadline is stated in the document.