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OPO to FSI: distance & flight time
Porto (Francisco de Sá Carneiro Airport) → Fort Sill (Henry Post Army Air Field (Fort Sill))
4,684 mi
7,539 km · 4,071 nm
9h 39m
estimated nonstop flight time
-6h
time difference · heading northwest
See live OPO→FSI fares Phone-only fares on this route — call free
Flight time details
4,684 miles nonstop takes roughly 9h 39m gate to gate, flying northwest. Add 45–90 minutes per connection if there's no nonstop service. Remember to factor the 6-hour time set-back when reading arrival times on your ticket.
The two airports
- OPO — Francisco de Sá Carneiro Airport · Porto, Portugal
- FSI — Henry Post Army Air Field (Fort Sill) · Fort Sill, 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 OPO
- BGZ · Braga Municipal Aerodrome26 mi away
- VRL · Vila Real Airport50 mi away
- VSE · Aerodromo Goncalves Lobato (Viseu Airport)55 mi away
- VGO · Vigo Airport68 mi away
Near FSI
- LAW · Lawton Fort Sill Regional Airport6 mi away
- DUC · Halliburton Field28 mi away
- HBR · Hobart Regional Airport44 mi away
- SPS · Sheppard Air Force Base-Wichita Falls Municipal Airport46 mi away
Frequently asked questions
How far is OPO from FSI?
The flight distance from Porto (OPO) to Fort Sill (FSI) is 4,684 miles (7,539 km, 4,071 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from OPO to FSI?
A nonstop flight takes about 9h 39m gate to gate. Actual time varies with winds, routing and season — eastbound transatlantic flights, for example, are usually faster than the return.
What is the time difference between Porto and Fort Sill?
Fort Sill is 6 hours behind Porto.
What is the cheapest way to fly from OPO to FSI?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on OPO–FSI that never appear on search engines, with no booking fees.