The flight distance from Adelaide International Airport (ADL) in Adelaide, Australia to St Mary's Airport (KSM) in St Mary'S, United States is 11,972 kilometers (7,439 miles / 6,465 nautical miles). The estimated flight time for this route is approximately 15h, flying north northeast at a heading of 25°.

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 Australia with United States. It is an intercontinental flight between Oceania and North America. Travelers should check visa requirements, customs regulations, and any travel advisories before booking.

Time zone information: When it's 00:21 in Adelaide, it's 04:51 in St Mary'S. With a 19.5-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 Adelaide (ADL) follows a heading of 227° (southwest). Actual flight times may vary depending on wind conditions, air traffic, and the specific aircraft used.

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