Software Testing - Terminal 5 software error cancelled 500 flights.
Welcome to another episode of my series about the most spectacular, interesting, and expensive software bugs. I already wrote about some of them (for e.q You Can check that one https://read.cash/@Otek/software-testing-mars-climate-orbiter-disaster-f33490c1), and today I want to cover a story about opening a new Terminal at Heathrow Airport.
Terminal 5
Heathrow Airport is also known as London Heathrow is a major English airport. It is the second-busiest European air hub with 22,109,726 passengers in 2020. So must admit it is quite huge :). No wonder, after some time, the airport authorities decided to open a new terminal: Terminal number 5. Construction of Terminal 5 at Heathrow Airport commenced in the summer of 2002. After about 6 years of work, in 2008 it was officially opened by the British Queen Elizabeth II. The new terminal was the largest free-standing building in the whole Great Britain and cost around 5.6 billion euros. It is intended only for the national carrier - British Airways and was to be the most modern in the world. So what Can go wrong - right? :)
Open-Day
The opening ceremony itself went very well. As I mentioned, the ribbon was ceremonially cut by the British Queen. The only disruption to the ceremony was the protests of environmentalists who opposed too much air traffic around the airport. But just after an hour late, the situation changes dramatically.
The airport began canceling flights and lost passengers got stuck in huge queues. There was complete chaos at the airport. Several fights took place among the nervous people. 34 British Airways flights were canceled on Thursday. Seven planes departed with passengers without luggage (except for hand luggage), and about 20 percent were canceled on Friday flights, including some for the second day in a row. Passengers were given blankets, a packed lunch, and promised reimbursement. Various inconveniences affected a total of 14 thousand passengers.
What happened?
So, what was the root of all those problems?
At first, the airport authorities claimed that everything was due to a purely mechanical failure of the new baggage system. It was for this reason that some passengers left without their luggage. Moreover, to avoid embarrassing criticism in connection with the cancellation of flights - a significant part of them were not canceled, even though passengers were not checked in as a result of the breakdown. The planes simply flew empty - and the passengers stayed at the airport - which further added to the chaos and nervousness.
But, after the airport returned to a normal working routine, more investigation was conducted. It turned out that the issue was not mechanical issues, but errors in the operation of the new software. As always, the final crash was the result of a few minor bugs that stacked up, including those related to insufficient software testing.
The list of these details is very long, but I found a great article that describes them exactly: https://www.zdnet.com/article/it-failure-at-heathrow-t5-what-really-happened/.
Dust
What were the costs of this software crash (of course, the scale of the problem was accompanied by additional errors, such as too little service)?
Around 430 flights have been canceled and more than 20,000 bags were separated from passengers. Citibank group has estimated that disruptions and flight cancellations could cost British Airways up to $50 million (£25 million).
Of course, apart from financial losses, the airport suffered huge image losses. British Airlines CEO Willie Walsh has admitted that the opening of the terminal, which has been built at a cost of £ 4.3 billion, is "not to be proud of".And the London Evening Standard newspaper even called it "national humiliation".
As always in the articles in this series, I want to point out how important and underestimated appropriate software testing can be. As you can see, the effects of this can be huge. If you liked this story, I encourage you to read other entries in this series :)
