Nonstop flight route between Fort Sill, Oklahoma, United States and Union Island, Saint Vincent and the Grenadines:
Departure Airport:

Arrival Airport:

Distance from FSI to UNI:
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- About this route
- FSI Airport Information
- UNI Airport Information
- Facts about FSI
- Facts about UNI
- Map of Nearest Airports to FSI
- List of Nearest Airports to FSI
- Map of Furthest Airports from FSI
- List of Furthest Airports from FSI
- Map of Nearest Airports to UNI
- List of Nearest Airports to UNI
- Map of Furthest Airports from UNI
- List of Furthest Airports from UNI
About this route:
A direct, nonstop flight between Henry Post Army Airfield (FSI), Fort Sill, Oklahoma, United States and Union Island Airport (UNI), Union Island, Saint Vincent and the Grenadines would travel a Great Circle distance of 2,768 miles (or 4,455 kilometers).
A Great Circle is the shortest distance between 2 points on a sphere. Because most world maps are flat (but the Earth is round), the route of the shortest distance between 2 points on the Earth will often appear curved when viewed on a flat map, especially for long distances. If you were to simply draw a straight line on a flat map and measure a very long distance, it would likely be much further than if you were to lay a string between those two points on a globe. Because of the large distance between Henry Post Army Airfield and Union Island Airport, the route shown on this map most likely appears curved because of this reason.
Try it at home! Get a globe and tightly lay a string between Henry Post Army Airfield and Union Island Airport. You'll see that it will travel the same route of the red line on this map!
Departure Airport Information:
IATA / ICAO Codes: | FSI / KFSI |
Airport Name: | Henry Post Army Airfield |
Location: | Fort Sill, Oklahoma, United States |
GPS Coordinates: | 34°38'58"N by 98°24'7"W |
Operator/Owner: | U.S. Army ATCA-ASO |
Airport Type: | Military |
Elevation: | 1189 feet (362 meters) |
# of Runways: | 1 |
View all routes: | Routes from FSI |
More Information: | FSI Maps & Info |
Arrival Airport Information:
IATA / ICAO Codes: | UNI / TVSU |
Airport Name: | Union Island Airport |
Location: | Union Island, Saint Vincent and the Grenadines |
GPS Coordinates: | 12°35'54"N by 61°24'52"W |
Area Served: | Union Island |
Airport Type: | Public |
Elevation: | 14 feet (4 meters) |
# of Runways: | 1 |
View all routes: | Routes from UNI |
More Information: | UNI Maps & Info |
Facts about Henry Post Army Airfield (FSI):
- Henry Post Army Airfield (FSI) currently has only 1 runway.
- The field was named in honor of pioneer aviator 2d Lieutenant Henry Post.
- The furthest airport from Henry Post Army Airfield (FSI) is Sir Gaëtan Duval Airport (RRG), which is located 10,920 miles (17,575 kilometers) away in Rodrigues Island, Mauritius.
- With the end of World War I, in October 1919 Post Field was deactivated as an active duty airfield in accordance with sharply reduced military budgets, and a small caretaker unit was assigned to the facility for administrative reasons to support the balloon school/company.
- There are no air units currently stationed at the airfield, however air operations for transient units are provided by permanent party personnel.
- The closest airport to Henry Post Army Airfield (FSI) is Lawton–Fort Sill Regional Airport (LAW), which is located only 6 miles (9 kilometers) S of FSI.
Facts about Union Island Airport (UNI):
- Because of Union Island Airport's relatively low elevation of 14 feet, planes can take off or land at Union Island Airport at a lower air speed than at airports located at a higher elevation. This is because the air density is higher closer to sea level than it would otherwise be at higher elevations.
- Union Island Airport (UNI) currently has only 1 runway.
- The furthest airport from Union Island Airport (UNI) is Umbu Mehang Kunda Airport (WGP), which is nearly antipodal to Union Island Airport (meaning Union Island Airport is almost on the exact opposite side of the Earth from Umbu Mehang Kunda Airport), and is located 12,203 miles (19,639 kilometers) away in Waingapu, Sumba, East Nusa Tenggara, Indonesia.
- The closest airport to Union Island Airport (UNI) is Canouan Airport (CIW), which is located only 8 miles (14 kilometers) NE of UNI.