[cschmatzler]

Whoever did not latch the door properly after doing maintenance checks. Which is either a mechanic at the airline itself or someone at a maintenance hub that is contracted by the airline. Not the job of the manufacturer whatsoever.

[AdamN]

The point s_dev is trying to make is that the designer can (and should) design things so that the mechanic "doesn't have to think". Seems like Airbus has evolved their design accordingly.

[GerryB]

The solution is actually quite elegant: a long tagged key required to open the door which remains in the lock until it's closed again. https://safetyfirst.airbus.com/preventing-fan-cowl-door-loss...

[s_dev]

So why did Airbus modify the door latch?

[cschmatzler]

They were required to by an airworthiness directive. https://www.federalregister.gov/documents/2017/06/29/2017-13...

[pfannkuchen]

To make the plane more user friendly?