Dan York has a very lengthy post about the VoIP packet traffic that Phweet and Tringme uses.
In his very knowledgeable way describes why long term the attempts to block VoIP are futile.
I agree, especially since it took me, a non-hacker, using a regular application called Flash from Adobe.
Instead of all this we need to focus on the potential ways the airlines can create talking zones, ala the smoking sections of the past, while at the same time think hard about what calls are essential and need to be made, and how to behave when on a packed plane with someone sleeping, or trying to work.
Give Dan's post a read.