Here's an article I found on David Angell, one of the victims, along with his wife in one of the plane crashes on 9/11/01. David was a writer and producer for Frasier, Cheers and Wings.
http://emmys.org/news/obit.htm

A terrible loss. Just like the 5,000+ that passed or are missing but probably have.

RIP

You're right, it is a huge loss - I don't even know him, but it was hard on me because he was a symbol of what I want to be - a successful sitcom writer/producer like David was. It's my dream. And to have him die in such a terrible way (not to mention all the other thousands) is difficult for even regular people like me to accept.

David Angell and his partners (Peter Casey and David Lee) were also reponsible for what I think are the absolute peak years of "Cheers" (1985-88). These were the fourth through sixth years, and comprised Shelley Long's last two seasons, and Kirstie Alley's first season. A very high concentration of classic episodes came from this period.

What a loss.