How far is Great Falls, MT, from Decatur, IL?
The distance between Decatur (Decatur Airport) and Great Falls (Great Falls International Airport) is 1239 miles / 1995 kilometers / 1077 nautical miles.
The driving distance from Decatur (DEC) to Great Falls (GTF) is 1490 miles / 2398 kilometers, and travel time by car is about 27 hours 21 minutes.
Decatur Airport – Great Falls International Airport
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Distance from Decatur to Great Falls
There are several ways to calculate the distance from Decatur to Great Falls. 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 Decatur to Great Falls?
The estimated flight time from Decatur Airport to Great Falls International Airport is 2 hours and 50 minutes.
What is the time difference between Decatur and Great Falls?
The time difference between Decatur and Great Falls is 1 hour. Great Falls is 1 hour behind Decatur.
Flight carbon footprint between Decatur Airport (DEC) and Great Falls International Airport (GTF)
On average, flying from Decatur to Great Falls 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 Decatur to Great Falls
See the map of the shortest flight path between Decatur Airport (DEC) and Great Falls International Airport (GTF).
Airport information
| Origin | Decatur Airport |
|---|---|
| City: | Decatur, IL |
| Country: | United States  |
| IATA Code: | DEC |
| ICAO Code: | KDEC |
| Coordinates: | 39°50′4″N, 88°51′56″W |
| Destination | 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 |