Yes, yes we very much do.
If I was the classify what this person has (allegedly / perhaps not / insert any other disclaimer here you like) done, it would be black hat whom had a ethical crisis. Yes he potentially exposed a security flaw, but on first discovering that flaw he did not report his findings, but rather claimed he repeated this process over many flights. By the repeating over and over he loses any claim to a grey hat.
Furthermore we need to shoot the messenger in this case since the methods he used to test this theory are just so dangerous. Let's for a second say he was successful. What exactly could he achieve other than put the flight into a worse position? It doesn't take a rocket scientist to work out that had he been successful the scale he was working on goes from absolutely no affect at one end, to flaming hole in the ground at the other.
Does the aircraft manufacturers hire white hat's? Don't know, but if they did, one can be certain that they would not be testing out their hacks on a plane in mid flight, since that would be no different that testing your own network securities strength by releasing actual viruses on it (also considered a really bad idea).