How far is Decatur, IL, from Great Falls, MT?
The distance between Great Falls (Great Falls International Airport) and Decatur (Decatur Airport) is 1239 miles / 1995 kilometers / 1077 nautical miles.
The driving distance from Great Falls (GTF) to Decatur (DEC) is 1488 miles / 2394 kilometers, and travel time by car is about 27 hours 6 minutes.
Great Falls International Airport – Decatur Airport
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Distance from Great Falls to Decatur
There are several ways to calculate the distance from Great Falls to Decatur. Here are two standard methods:
Vincenty's formula (applied above)- 1239.474 miles
- 1994.739 kilometers
- 1077.073 nautical miles
Vincenty's formula calculates the distance between latitude/longitude points on the earth's surface using an ellipsoidal model of the planet.
Haversine formula- 1236.909 miles
- 1990.611 kilometers
- 1074.844 nautical miles
The haversine formula calculates the distance between latitude/longitude points assuming a spherical earth (great-circle distance – the shortest distance between two points).
How long does it take to fly from Great Falls to Decatur?
The estimated flight time from Great Falls International Airport to Decatur Airport is 2 hours and 50 minutes.
What is the time difference between Great Falls and Decatur?
Flight carbon footprint between Great Falls International Airport (GTF) and Decatur Airport (DEC)
On average, flying from Great Falls to Decatur generates about 163 kg of CO2 per passenger, and 163 kilograms equals 359 pounds (lbs). The figures are estimates and include only the CO2 generated by burning jet fuel.
Map of flight path and driving directions from Great Falls to Decatur
See the map of the shortest flight path between Great Falls International Airport (GTF) and Decatur Airport (DEC).
Airport information
| Origin | Great Falls International Airport |
|---|---|
| City: | Great Falls, MT |
| Country: | United States  |
| IATA Code: | GTF |
| ICAO Code: | KGTF |
| Coordinates: | 47°28′55″N, 111°22′15″W |
| Destination | Decatur Airport |
|---|---|
| City: | Decatur, IL |
| Country: | United States |
| IATA Code: | DEC |
| ICAO Code: | KDEC |
| Coordinates: | 39°50′4″N, 88°51′56″W |