[Info-vax] Off-topic follow-up, now with actual data - mileage vs. speed

[JF Mezei]

On 13-12-22 14:19, spamsink2001 at yahoo.com wrote:

> How is this done?

On jet engines, it has to do with a lot fo factors, but I surmise the
biggest one is the gearing between the jet and the turbofan. They know
at what speed the fan needs to run for cruise speed at altitude, they
know what the best speed for the turbine is, so they gear accrodingly.

Very complex formulas involved due to plane flying at different
altitudes (air pressure and temperature).