New Customs procedures in Russia affect foreign aircraft planning to conduct private and commercial flights on domestic legs within the country. It’s called Import 53 (IM53) and, according to international aviation operations information provider FltOps Group, “Some of the Customs authorities at airports in Russia don’t even understand it themselves.”

Air taxi, charter, and other commercial operations technically are not allowed to fly domestic legs in Russia under any circumstances—the same rule as previously existed and a fairly standard cabotage rule the world over. However, under IM53, domestic flights by private aircraft operations are permitted if the aircraft’s basic operating weight is below 62,000 pounds and there are fewer than 19 passenger seats.

“But, to get IM53 approval, you have to request it directly with Customs yourself, or use a customs broker,” FltOps Group said. “The handling agents we’ve spoken to say they are not allowed to help with this.” Some FltOps Group members said this new rule is already affecting trips to Russia and that local Customs at smaller airports are as confused as everyone else about exactly how to interpret them.

Historically, basic cabotage rules have not been strictly enforced in Russia, “with operators often being able to do multiple domestic legs, or change the passengers onboard on different legs, or declare charter flights as private to avoid the cabotage rules altogether,” FltOps Groups said. “But with the new IM53 rule, the authorities seem to be attempting to establish a standard rule and position on the whole issue of cabotage.”