The flight distance from Cape Town International Airport (CPT) in Cape Town, South Africa to St Mary's Airport (KSM) in St Mary'S, United States is 16,888 kilometers (10,493 miles / 9,119 nautical miles). The estimated flight time for this route is approximately 21h, flying north at a heading of 2°.

This is an ultra-long-haul route, one of the longest in aviation. It requires wide-body aircraft with extended range capability such as the Airbus A350-900ULR or Boeing 777-200LR. Passengers should prepare for an extended flight with multiple meal services.

This is an international route connecting South Africa with United States. It is an intercontinental flight between Africa and North America. Travelers should check visa requirements, customs regulations, and any travel advisories before booking.

Time zone information: When it's 14:59 in Cape Town, it's 03:59 in St Mary'S. With a 11-hour time difference, travelers should plan for significant jet lag. It typically takes one day per hour of time difference to fully adjust.

The return flight from St Mary'S (KSM) to Cape Town (CPT) follows a heading of 357° (north). Actual flight times may vary depending on wind conditions, air traffic, and the specific aircraft used.

For more information about these airports, visit the Cape Town International Airport (CPT) and St Mary's Airport (KSM) detail pages, or use our flight duration calculator to compare other routes.