Isnt it to prevent one pilot from locking the other out and flying the ac into a mountain on purpose?
Then there is this reasoning:
The German airline association BDL announced the change, which will come into effect by 1 June, on its website. It said its airlines will be re-introducing their original cockpit safety procedures.
BDL said that its airlines had “independently” reviewed the rules and decided that the two-person rule had no safety benefits – and could actually be more dangerous.
The group said the changes caused “more frequent and predictable” opening of the cockpit door and expanded the number of people with access to the cockpit.
Lufthansa, the country’s biggest airline, is one of the groups removing the requirement. Its airlines include Austrian Airlines, Swiss Airlines, and Eurowings – which was merged with Germanwings in 2015, a process which had begun before the company’s high-profile crash.
https://onemileatatime.com/two-perso...ule-abolished/