TUI Boeing 737 flight faced a close call last October when nearly 200 passengers were put at risk of oxygen deprivation while circling over London. A recent report has revealed that a series of maintenance failures and missed warning signals led to a potentially catastrophic situation onboard.

According to the Air Accidents Investigation Branch (AAIB), the flight was forced to turn back to Manchester after key safety systems responsible for cabin pressurization were inadvertently left switched off during routine maintenance. As a result, the aircraft failed to maintain proper cabin pressure, leaving 187 passengers vulnerable to hypoxia, a condition caused by insufficient oxygen in the bloodstream.

While the crew managed to reactivate the pressurization systems during the plane’s climb, further complications soon emerged. A fault in the air conditioning system triggered a “master caution” warning, prompting the decision to return to Manchester. However, the aircraft was too heavy to land immediately, forcing it to circle above London while waiting for clearance to burn off excess fuel.

During this holding pattern, a critical warning signal was overlooked, which meant that both passengers and crew were at risk of impaired cognitive function due to reduced oxygen levels. The plane remained airborne longer than anticipated to allow for a safe landing, extending the exposure to the dangerous condition of hypoxia.

The investigation also raised concerns about crew fatigue, as the pilot had limited rest prior to the flight. Despite the sequence of technical failures and human errors, the aircraft successfully landed in Manchester at 8:10 AM without any reported medical issues.

This incident underscores the critical importance of thorough maintenance procedures, comprehensive training, and vigilant oversight to prevent similar situations from occurring in the future. It also highlights the potential risks associated with human error, especially in situations where time and resources are limited, further emphasizing the need for heightened safety protocols and continuous improvements within the aviation industry.