After Germanwings tragedy, it's time to review the rules governing pilots

The aviation industry has an enviable safety record. A willingness to learn from mistakes and improve, coupled with a strong regulatory system, has made flying to a destination safer than walking across a street. But Andreas Lubitz, the 27-year-old co-pilot whom prosecutors believe deliberately crashed Germanwings Flight 9525, killing all 150 people on board, has exposed flaws that will be challenging to fix. Medical certification, training and cockpit practices are just three aspects of commercial flight that have to be reviewed.

Pilots are required to be highly skilled and have perfect physical and mental health. They are no longer determined fit to fly if any of their faculties, such as eyesight, fail; regular medical checks ensure standards are met. Lubitz is believed by investigators to have been hiding a mental illness that, if detected or reported to the airline's medical examiners, could have curtailed his working life as a pilot. The expense and time spent training and dreams of one day captaining a big plane would have, in an instant, been in vain.

Regular medical examinations are a trying time for pilots; there are only two outcomes, one directly affecting a career. In such circumstances, it is understandable - but not excusable - that medical conditions could be concealed or strategically handled. A global shortage of pilots, differing experience requirements around the world for co-pilots and captains and the strains created by the rise of budget airlines further the problems. The less flying time, the fewer the number of medical checks and the less likelihood colleagues would be able to observe and scrutinise attitudes and behaviour. Safety regulations imposed after the September 11, 2001, terrorist attacks in the US made it possible for the Germanwings' captain to be locked out of the cockpit, raising questions about the rule and how many crew should be at an aircraft's controls at any one time.

Pilots can have the lives of hundreds of people in their hands. No matter how automated aircraft become, those at the controls have to always have a moral sense of duty to passengers. They have to be honest during medical examinations and be willing to give up their medical privacy to employers and regulators. But the Germanwings tragedy also makes clear that cabin practices and the training and experience of co-pilots should also be reviewed. Only by preventing a repeat can safety standards be lifted even higher.