CO & RVSM
Funny exchange I heard last week on MIA center frequency somewhere between St. Croix and West Palm:
MIA: COXXX, due to traffic, I'll need to climb you to FL340 or 380. Which would you like?
COXXX: Um, aren't those kind of odd altitudes?
MIA: You're entering RVSM airspace.
(Silence)
MIA: That's Reduced Vertical Separation Minimum.
COXXX: Uh, we'll take FL340.
I'll bet CO was thankful that MIA didn't ask them whether they were RVSM approved!