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by ubernostrum 2961 days ago
Planes don't spend all their time flying. A significant part of the time they are being boarded or people are stepping out, and freight is being loaded and unloaded, and the plane is service, fuel tanks are filled, catering material brought in, wings are de-iced.

The turnaround time -- time needed for everything that happens from when the plane arrives at the gate to when it departs again -- is only comparable to flying time for smaller aircraft doing shorter domestic hops.

For aircraft doing the kinds of inter-continental segments a supersonic airliner is targeting, there's no real comparison. And airlines most certainly do optimize for time spent in the air; a plane on the ground is a plane making no money. So you see a single aircraft bounce around among a bunch of hubs all in one day, for example, or larger, longer-range aircraft doing rotations of where they fly to (like having the same aircraft do a flight from the US to South America and back, then off to Asia and back, to optimize for arrival/departure times and minimize time spent not flying)
1 comments
ptaipale 2960 days ago
Of course airlines optimize it, but still, boarding alone takes a significant portion of the total time needed for a long-haul flight.

If I look at the latest long-haul flight I took, the flight time was 11 hours, turn-around time at airport 4 hours, for a total of 15 hours. If you'd drop the flight time to half, and manage to do accelerate boarding, cleaning, re-fueling etc in 3 hours, you'd come up with 8.5 hours. Much better, but not even close to be able to deliver twice as many flights per day. It'd be more like a 50 % improvement.

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ubernostrum 2955 days ago
Long-haul utilization also depends on one other factor, which is time zones. It can be worth leaving the plane on the ground longer in order to line up for a more desirable departure/arrival time.

You see this a lot with transatlantic flights, where they spend more time than necessary on the ground at each end, but doing so sets up better timing (like eastbound TATL flights departing in North American evening and arriving in European morning).

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