ATC
RVSM rules take effect in North America
Whether pilots notice any difference remains open to debate, but anyone cruising in the upper flight levels over North America should at least be aware tha

Whether pilots notice any difference remains open to debate, but anyone cruising in the upper flight levels over North America should at least be aware that they are passing much closer to other airplanes now that the mandate for reduced vertical separation minimums (RVSM) is in force.

At precisely 0901 UTC (4:01 a.m. EST) on January 20, RVSM rules went into effect in the U.S., southern Canada, Mexico, South America and the Caribbean flight information region. The rules have already been implemented over the North Atlantic, the Pacific, in Europe and in many other parts of the world, leaving North America as one of the last heavily traveled regions to adopt the reduced-separation standards.