Citation III; VI; VII (C650)
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Flight Instructor
Flight Crew Last 90 Days 62; Flight Crew Total 6800; Flight Crew Type 516
Communication Breakdown; Confusion
ATC Issue All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Clearance
Air Traffic Control Issued New Clearance; Flight Crew FLC complied w / Automation / Advisory
Procedure; Human Factors; Aircraft
Current aircraft operator did not have RVSM authorization letter. When we reached the cruising altitude of FL280 we found that we were in the tops of a cloud layer and it was choppy there. We asked for higher and reported negative RVSM. Center cleared us to climb to FL320. When Center handed us off to [the next Center controller] we checked in negative RVSM. [The next Center] told us to descend to FL280 and call a number about a possible pilot deviation.I found out that we are not supposed to be allowed to cruise at an RVSM altitude without RVSM approval. I thought the controller could let you into RVSM airspace traffic and workload permitting; but that is actually only to climb or descend through RVSM; not cruise in it.
C650 First Officer reported being non-RVSM; yet ATC allowed clearance into RVSM airspace.