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A comment on Drop the Supersonic Aircraft Ban. Parent comment

Re:Drop the Supersonic Aircraft Ban by lujim on Monday June 13, 2016 @02:54PM (#11896330)
That is coefficient of drag. You have to remember that goes into the drag equation which includes velocity squared.

force_of_drag = .5 * mass_density * (velocity^2) * coefficient_drag * area.

As that coefficient starts tapering off after transonic drag decreases velocity squared is there to ramp up the drag.

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Re:Drop the Supersonic Aircraft Ban by Gravityloss on Monday June 13, 2016 @03:38PM (#11896759)
As lift is also proportional to density, area and square of velocity, that whole term cancels out from the equation of fuel usage per distance, basically only L/D or cL/cD matters.

In practice it might be a bit more complicated.

EDIT: indeed here we can see that Concorde had lift to drag ratio of only 7.5 at Mach 2, while Boeing 747 has 17.7 at Mach 0.9 or so. https://en.wikipedia.org/wiki/Lift-to-drag_ratio

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Re:Drop the Supersonic Aircraft Ban by DrScump on Monday June 13, 2016 @04:38PM (#11897413)
But you should also factor in their comparative passenger capacities (e.g. impact per passenger-mile).
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Re:Drop the Supersonic Aircraft Ban by Gravityloss on Monday June 13, 2016 @06:06PM (#11898113)
Perhaps better would be aircraft weight to number of passengers ratio. Revenue wise the supersonic airliner flies faster, meaning you get more seat miles per day per seat.
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Re:Drop the Supersonic Aircraft Ban by mchouza on Monday June 13, 2016 @03:22PM (#11896594)
That's true, but supersonic planes also travel higher (Concorde -> 18 km, XB-70 -> 22 km). The real problem is that L/D decreases at supersonic speeds. For example, the XB-70 had a L/D of about 7, while the 707 had a L/D over 18...
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