The flight distance from South Big Horn County Airport (GEY) in Greybull, United States to Noi Bai International Airport (HAN) in Hanoi, Vietnam is 11,935 kilometers (7,416 miles / 6,444 nautical miles). The estimated flight time for this route is approximately 15h, flying north northwest at a heading of 327°.

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

Time zone information: When it's 01:40 in Greybull, it's 15:40 in Hanoi. With a 14-hour time difference, travelers should plan for significant jet lag. It typically takes one day per hour of time difference to fully adjust.

There is a significant elevation difference of 3,903 feet between the two airports. Noi Bai International Airport sits lower than South Big Horn County Airport.

The return flight from Hanoi (HAN) to Greybull (GEY) follows a heading of 25° (north northeast). Actual flight times may vary depending on wind conditions, air traffic, and the specific aircraft used.

For more information about these airports, visit the South Big Horn County Airport (GEY) and Noi Bai International Airport (HAN) detail pages, or use our flight duration calculator to compare other routes.