The flight distance from St Louis Downtown Airport (CPS) in Cahokia/St Louis, United States to Noi Bai International Airport (HAN) in Hanoi, Vietnam is 13,161 kilometers (8,178 miles / 7,107 nautical miles). The estimated flight time for this route is approximately 16h, flying north northwest at a heading of 343°.

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 03:17 in Cahokia/St Louis, it's 16:17 in Hanoi. With a 13-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 Hanoi (HAN) to Cahokia/St Louis (CPS) follows a heading of 14° (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 St Louis Downtown Airport (CPS) and Noi Bai International Airport (HAN) detail pages, or use our flight duration calculator to compare other routes.