ARG/US: an independent US-based safety auditor with three operator ratings — Gold, Gold Plus, Platinum. Platinum requires an on-site audit and meaningful operational maturity. The majority of credible US operators carry at least Gold Plus.
Wyvern: the second major US safety standard, with Wingman and Wyvern Wingman PRO ratings. Many US Part 135 operators carry both ARG/US and Wyvern certification.
IS-BAO (International Standard for Business Aircraft Operations): the IBAC-administered global standard, with Stages 1, 2 and 3. Stage 3 is the meaningful level for European operators.
EASA AOC: the European Aviation Safety Agency's Air Operator Certificate, mandatory for any European commercial private aviation operator. AOC verification is the minimum baseline; safety culture above that requires the ratings above.
Practical rule: verify both the operator AND the specific aircraft. An operator can hold a Platinum rating on its primary fleet but operate a sub-charter through a smaller carrier on a given leg. Confirm the actual operator on your charter contract.
