You can fly the Citation 1, 2, s2, Ultra and Encore. Unless you have an SP on your Type Rating, you cannot fly single pilot.
I asked this same question when I got my CE500 type in December of 1999 at FSI Toledo. Hopefully this is 100% accurate. With regard to an FAR to check this...don't know if there is one. Call FSI and ask them if you want to verify.
CE500 is a great type to have. Lots of them out there and they are easy to fly.
Not to be picky, but when I mentioned the Excel I was responding to "Jetz" list of all Cessna Citation types. (he forgot to include the Excel) But you're right, the Excel is a totally different type: CE-560XL.
I thought so too, but tell that to the ICT FSDO, and the check airman at FSI, they insisted to me that this is not the case. They said the SP rating on the pilot was only so that he can fly the CE500, 550 and 560, and not the 501 or 551...I'll have to write FAA in OKC on this to get a final answer I guess or better yet call Cessna.
I'm hearing the same thing as V70T5. Simuflite in DAL told a bud of mine the same thing about the 551, no SP requirement for the pilot, only the type since the original certification for that particular plane is single pilot. I believe the LIT FSDO agreed when he called to confirm. This was a newsflash for me, learning every day.
I called Cessna, and they too confirmed it. They said that FAA agrees with this set up but most insurance wants an SP rated pilot. Myself, SP rated or not, I would never fly a turbojet airplane into a busy major airport or even a busy airspace like NY approach without an FO....(or Captain) along.