Software Glitch Led To ‘Serious’ Tui Flight Incident

Investigators find ‘simple’ software problem due to language difference led to flight being more than one tonne heavier than expected

A “simple” software error due to a language difference led to a Tui flight from Birmingham last year being more than one tonne heavier than expected, investigators have found.

The Air Accidents Investigation Branch (AAIB) classed the problem affecting the flight from Birmingham to Majorca with 187 passengers on board as a “serious incident”.

The airline Tui had updated its reservation system during the months when its planes were grounded due to the coronavirus pandemic, and the new system wrongly allocated 38 passengers a child’s “standard weight” of 35kg rather than the adult standard of 69kg.

Image credit: Tui flight
Image credit: Tui

Language difference

As a result the load sheet, produced for the captain to indicate factors needed for take-off, stated the Boeing 737 was more than 1,200kg lighter than it actually was.

The flight was an early-morning departure from Birmingham International on 21 July 2020.

The error was due to a “simple flaw” in an IT system that was programmed in an unnamed country where the title “Miss” is used for a child and “Ms” for adult women.

However, the issue caused thrust for departure to be only “marginally less” than it should have been and the “safe operation of the aircraft was not compromised”, the AAIB’s report found.

The same issue caused two other Tui flights leaving the UK later that day to have inaccurate load sheets.

Safety

Tui subsequently brought in manual checks to ensure adult women were referred to as “Ms” on relevant documents, and the problem was later fixed through a software update.

“The health and safety of our customers and crew is always our primary concern,” Tui said. “Following this isolated incident, we corrected a fault identified in our IT system.

“As stated in the report, the safe operation of the flight was not compromised.”