"John Keeney" wrote in message
...
It's been too long since I've seen it, what were the details that
determined the types?


Although bufdrvr answered your question, if you are interested in more
detail about B-52 models and service see the series of articles at:

http://home.att.net/~jbaugher2/b52.html where you will find that it is an
amazing aircraft.

Regards,

Tex Houston