The only airline that could possibly
have operated every single 747 variant is JAL.
JAL and ANA are the only two operators of both the 747SR and the 747-400D. ANA, though, has never had SUD versions of the 747, and I don't think they've operated all the cargo types that JAL has. So that leaves JAL as the only possibility.
I know JAL has operated 747-100's, -200's, -300's, -400's, SR
's, 400D's, and all freight versions. I don't know if they've ever operated any combi's or SP's. If they haven't, though, then the answer to this question is "nobody", because nobody else besides ANA has operated SR's and 400D's.
I also should have been specific that Qantas operated all PAX variants.
In fact you can get pretty nuts with this. Technically, UPS and I think Evergreen are the only carriers that have ever flown a 747SR cargo config (repurposed from JAL and ANA pax fleets). But even if you're going to limit it to airplanes actually in the Boeing catalog, then it's either JAL or it's nobody.
[Edited 2004-12-16 06:31:37]
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