Concerns over door safety have risen after investigators believe the co-pilot of Germanwings Flight 9525 deliberately crashed the Airbus A320-200 into the French Alps on March 24, 2015 after locking crew members out of the cabin.

There is much handwringing in the press and by TV pundits that we are faced with a conundrum: either make cockpit doors impossible to break down and lockable from inside, or compromise them with some method of opening them from outside the cockpit, even when the pilot inside locks out the other crew. In other words, compromise the impenetrable door designed to lock out hijackers.

I suggest that we can keep the door safety we have, yet provide for scenarios where a pilot or other intruder is up to no good inside a locked cockpit. It is technologically feasible to send a message to an airline’s dispatch office on an emergency frequency telling them that they must open the door remotely. A discreet signal could be sent to do exactly that. We can do that with our cars these days; I downloaded that feature for my car recently; Why not for airliners? Sure, it is more complicated than for cars, as it would likely require up and down links to satellites. But, that technological complexity is surely not insurmountable.

In an emergency, when an airplane is diving toward disaster and a cockpit door is locking out crew members, there ought to be an app for that.