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submitted 8 months ago by Nakoichi@hexbear.net to c/news@hexbear.net

BUILD TRAINS I AM BEGGING YOU

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[-] dat_math@hexbear.net 7 points 8 months ago

The question then becomes how much people are prepared to pay for 50% shorter flights, and how much the cost of supersonic flight has been reduced by improved technology.

My main questions center on how much extra fuel is required to provide all that additional energy? Idk enough about fluid mechanics to answer this on my own: how much more energy does it take to accelerate from mach 1.1 to mach 1.2 vs mach 0.9 to mach 1.1?

[-] plinky@hexbear.net 5 points 8 months ago* (last edited 8 months ago)

it's not acceleration, it's air friction vs plane geometry, supersonic airflow has different optimal characteristics both for engines and flight surfaces/wings (naive kinetic energy is just differences of speed squared though).

But performing the Mach-cutoff flight “burns more fuel on the same distance than both subsonic and supersonic flight”, says Liebhardt. That makes it less economically viable than a regular supersonic flight and “the worst speed to fly at for fuel economy”. He sees Mach-cutoff flights as being more of a niche use case for “supersonic business jet users”, rather than for commercial airlines.

from new scientist

seems like they get shit of both worlds tbh with fuel economy (not zoomy enough to just cross distance fast with godawful fuel consumption/not optimized enough for flight at those speeds via engine regimes/geometry (that part might be fixable, but depends on how long it spends on subsonic climb/descend part of journey)

[-] dat_math@hexbear.net 4 points 8 months ago

oh that makes so much sense thank you!

this post was submitted on 09 Jun 2025
91 points (100.0% liked)

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