Most people don't want to make calls on a plane
I once had a conversation with a barber who told me he cut the hair of an airline pilot. One of the things he'd learned from him was "the reason they don't let you use your phone on a plane is because they're an annoyance. If they made the plane crash, they would take 'em off you before you even got on. A terrorist wouldn't need to twat about with bombs and that... they'd just send someone a text."
He then added a nice story about how the crash position we're told to adopt is to "kill you quicker. AND it impales your head on your spine so they can identify bodies easier." I was going on holiday the next day and puked the entire journey.
On the topic of phones on a plane, it seems that the majority of Brits actually don't want regulations on in-flight phone usage relaxed, despite the fact that the regulations were actually relaxed ages ago.
Someone conducted a survey in an attempt to drum up some business for themselves, who we're peevishly not crediting here (but The Reg, have), asked more than 1500 people if they "welcomed the change in legislation that allows passengers to use their mobile phones".
Basically, a big chunk of people didn't want their flights disturbed by people chattering away like idiots on trains. It seems that our inability to make calls in the air is a commercial issue rather than a regulatory one.
Basically, the only reason why we don't have the ability to do it currently is because airlines can't be arsed fitting something called a femtocell (which is a tiny base station and sounds like a treatment for female thrush) and a satellite uplink to carry the calls.
A femtocell costs airlines money every time a phone registers with the network. Airlines don't want to induce a cost unless there's a massive demand for it - which there isn't as over half of people over-35 have flatly stated that they don't want in-flight calling.
It does mean, however, that if you leave your phone on by accident, you don't have to shit your pants with fear.