Flight Time Calculator

Divide the great-circle distance by the effective cruise speed, then add a fixed allowance for taxi, climb and descent. That fixed part is typically 30 to 60 minutes and it does not shrink for a shorter route.

Because the fixed ground and manoeuvring time is a much larger share of a short flight. A 500 km hop can spend a third of its block time not at cruise, which is also why short-haul emissions per kilometre are so much worse.

The jet stream. Transatlantic eastbound flights ride a tailwind of 100 to 200 km/h and westbound fight it, which routinely produces an hour or more of difference on the same route.

Gate to gate, including taxi at both ends — the figure airlines schedule against. Air time is shorter, and the gap is why a flight can be late off the gate and on time on arrival.

It is the shortest path over a sphere, which on a flat map looks curved. It is why a London to Tokyo route passes near the Arctic rather than following a straight line on the chart.

Indirectly. Higher altitudes have thinner air and less drag, so true airspeed is higher for the same fuel — but the climb takes time and fuel, which is why short flights cruise lower.

A band of fast-moving air in the upper atmosphere, typically 100 to 200 km/h and occasionally far more. Aircraft route to use it eastbound and avoid it westbound, which is most of the transatlantic time difference.

Because on-time performance is measured against the published schedule. Adding buffer to the block time makes arrivals look punctual, and it has grown steadily over decades for exactly that reason.

Rules governing how far a twin-engine aircraft may fly from a diversion airport. Higher ratings permit more direct oceanic routes, which is why modern twins fly polar and mid-ocean tracks that older ones could not.

Great-circle distance between airports, which is the shortest path over a sphere. Actual tracks are longer because of airways, weather and airspace restrictions.

Marginally, and mostly through a lower optimum cruise altitude early in the flight. The effect on block time is small compared with wind.

Wind, routing and traffic. A transatlantic sector can vary by an hour between days on identical equipment, which is why schedules are built on averages rather than best cases.