The European Union has common regulations on pilot training, licensing and medical certification. The same is true for equipping planes with secure cockpit doors. Following the crash of Germanwings flight 4U 9525, both the European Aviation Safety Agency (EASA), which is based in Cologne, and the European Commission confirmed these EU-wide standards at a press conference in Brussels.

According to EU officials who declined to be named, the common European regulations specify the minimum safety standards to which airlines must adhere. Airlines may also choose to impose stricter safety guidelines on themselves. National flight safety officials are responsible for ensuring that the minimum standards are met. In Germany, this is the Federal Aviation Office in Dusseldorf.

Europe has only had common aviation safety rules since the September 11, 2001 terrorist attacks on the United States. Previously, every member state was responsible for issuing its own regulations.

Checking psychological health

European Commission and EASA representatives also confirmed that pilots undergo medical examinations at least once a year. The exams include a psychological assessment to check for mental illness such as depression, they said.

"Pilots suffering from depression are considered unfit to fly, and they are not given their flight certification," one EU official said during a background discussion. Pilots also have a responsibility to tell their employer if they have a condition that would make them unfit to fly.

But Thorsten Onno Bender, a German doctor who regularly examines pilots, said the reality is different. He told DW that psychological illness is difficult to diagnose during a routine medical exam. He also said that there are no compulsory psychological tests.

The EASA representative in Brussels declined to comment on the circumstances around the Germanwings crash or the details that have emerged about co-pilot Andreas Lubitz's illness. A French prosecutor has accused Lubitz of deliberately crashing the plane, which was carrying 149 other people.

Measures aimed at threats from outside

After September 11, EASA required all airlines that take off or land in Europe to install secure cockpit doors. "But the point was to stop people outside the cockpit from getting in," an EASA representative said.

It appears that no one considered the possibility that the threat could come from one of the pilots. Europe also requires cockpits to be equipped with cameras to monitor the area in front of the cockpit door. One pilot is allowed to leave the cockpit for a short time, because the other pilot can see who is at the door. For that reason, EASA previously didn't consider it necessary to always have two people in the cockpit.

In the US, where cockpit cameras are not required, a second person is only needed to look through the door's peephole and open it to authorized personnel. "The two-person rule in the US and at some European airlines was never designed to monitor the remaining pilot in the cockpit," the EU official in Brussels said.

The Green Party's Michael Cramer, chairman of the European Parliament's transport committee, told German public radio he wants to see the introduction of a common EU-wide regulation requiring two people to always be present in the cockpit.

"The question is whether the co-pilot would have behaved the same way if he'd had a flight attendant next to him. When there was a knock on the door, could he then have prevented the door from being opened?" Cramer asked.

German airlines have announced that, for the time being, they will introduce the two-person rule and remain in consultation with the Federal Aviation Office. British Airways, Scandinavia's SAS, and Latvia's Air Baltic have already said they would implement the rule. Czech airline CSA and Europe's biggest low-cost airline, Ryanair, had already adopted a similar policy prior to Tuesday's crash.

Increased ground control

Given the circumstances surrounding the Germanwings crash, the European Commission and EASA intend to check whether new regulations for compulsory presence in the cockpit are necessary.

"That could take some time, because we still don't have all the facts," one EASA spokeswoman said. The organization could issue regulations at short notice in emergency situations, but according to EU authorities, there is no emergency at present.

Officials will also discuss whether changes need to be made to the locking mechanism on cockpit doors. The safety doors have had an overall positive effect, an EU spokeswoman said. "They have drastically reduced the number of hijacked planes worldwide," she said.

In the long term, the European Commission and EASA will also consider whether civilian aircraft should be subject to more control from air traffic controllers on the ground in order to prevent pilot error or criminal behavior, as was the case on the Germanwings plane.

But tests with "remote-controlled" jets are relatively new. With advances in technology, it could also one day be possible to fly planes with just one pilot on board, as long as a member of the cabin crew has some emergency training. Options like these are strictly for future consideration, though, said the EASA and EU representatives in Brussels.