Autothrottle Failure on Boeing 737-800 at Bristol Airport Sparks Investigation

On March 4, 2024, a serious incident involving a Boeing 737-8K5 (G-FDZS) during takeoff from Bristol Airport has prompted an in-depth investigation by the Air Accidents Investigation Branch (AAIB). The aircraft experienced an unexpected autothrottle (A/T) failure, raising concerns about operational safety and pilot response protocols.

The incident unfolded on Runway 09 when the autothrottle disengaged just as the takeoff mode was selected. This critical system malfunction led the flight crew to manually set the thrust at 84.5% N1, significantly below the required 92.8% N1 for a safe takeoff. Unfortunately, neither pilot noticed the incorrect thrust setting, and standard operating procedures (SOPs) failed to catch the error.

The AAIB has issued a special bulletin with preliminary information on this troubling event. The bulletin serves as a crucial alert to pilots and operators of the Boeing 737 Next Generation (737NG) series, detailing the autothrottle disengagement and outlining the necessary actions crews should take in such scenarios. This early communication aims to prevent similar incidents in the future by emphasizing the importance of vigilance and adherence to SOPs.

As the investigation continues, the AAIB is meticulously examining all aspects of the incident, including mechanical factors, pilot training, and procedural adherence. The final report will provide a comprehensive analysis and potentially recommend further safety measures to enhance the reliability of autothrottle systems and pilot responses.

This incident at Bristol Airport underscores the critical nature of system redundancies and the constant need for rigorous pilot training. It serves as a reminder of the complexities of modern aviation and the importance of immediate and precise responses to technical failures. The forthcoming AAIB report is eagerly anticipated, as it will likely influence future aviation safety standards and training programs.