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BIG to KSM: distance & flight time
Delta Junction (Allen Army Airfield) → St Mary's (St Mary's Airport)
565 mi
909 km · 491 nm
1h 42m
estimated nonstop flight time
Same time
time difference · heading west
See live BIG→KSM fares Phone-only fares on this route — call free
Flight time details
565 miles nonstop takes roughly 1h 42m gate to gate, flying west. Add 45–90 minutes per connection if there's no nonstop service. Both airports share the same local time, so schedules read exactly as flown.
The two airports
- BIG — Allen Army Airfield · Delta Junction, United States
- KSM — St Mary's Airport · St Mary's, United States
Distances are great-circle ("as the crow flies") — the same basis airlines use for frequent-flyer miles.
Alternate airports can cut this fare
Flying from or into a nearby airport is the #1 trick our agents use to beat online prices. Call and we'll compare every combination on one call.
Near BIG
- EIL · Eielson Air Force Base62 mi away
- FBK · Ladd AAF Airfield81 mi away
- FAI · Fairbanks International Airport85 mi away
- TKJ · Tok Junction Airport96 mi away
Near KSM
- MOU · Mountain Village Airport13 mi away
- MLL · Marshall Don Hunter Sr Airport44 mi away
- AUK · Alakanuk Airport61 mi away
- EMK · Emmonak Airport63 mi away
Frequently asked questions
How far is BIG from KSM?
The flight distance from Delta Junction (BIG) to St Mary's (KSM) is 565 miles (909 km, 491 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from BIG to KSM?
A nonstop flight takes about 1h 42m gate to gate. Actual time varies with winds, routing and season — eastbound transatlantic flights, for example, are usually faster than the return.
Are there nonstop flights from BIG to KSM?
Nonstop service on BIG–KSM depends on the season and the day of week. Run the fare search on this page with the nonstop filter applied to see current direct options; when there is no nonstop, a single connection through a carrier hub adds roughly 2–4 hours to the 1h 42m nonstop estimate.
What is the cheapest way to fly from BIG to KSM?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on BIG–KSM that never appear on search engines, with no booking fees.
Why are some BIG to KSM fares phone-only?
Consolidator contracts let us sell certain BIG–KSM tickets below the price airlines permit us to publish online, so those fares can only be quoted over the phone. Call the travel desk and an agent will check phone-only inventory for your dates.