Meno – above the asterisk is a link to their Kashrus Kurrents article on the topic. If the mods let in the link, here it is:
http://www.star-k.org/articles/kashrus-kurrents/601/dont-drink-the-coffee/
As for the airplanes, I believe the reasoning is based on the Noda B’Yehuda that the article quotes. I have not seen it in a while, but IIRC he says that the lack of an alternative makes it an automatic b’dieved. So if you are on an airplane and need a coffee, since there is no other way to get a coffee it would be muttar to drink it.