Dittoing userbinator here. Avionics systems aren't generally treated so casually. DO-178B [0] has several levels of designations for criticality of systems. A is the highest. Essentially, if these fail, people will die. E is the lowest. If these fail, people are inconvenienced. Passenger AV systems, wifi, those are conveniences and are not held to a terribly high standard.

[0] http://en.wikipedia.org/wiki/DO-178B