Originally Posted by justageek
How would flying slowly save money? I assume there's an optimal airspeed for fuel efficiency, and that this is the airpseed that is always used (?)
Also, how did you know your groundspeed in an MD80?
Even assuming the groundspeed of the MD80 was 400-425 (knots or mph? - the OP doesn't indicate), that seems pretty fast for a westbound airplane that typically cruises at 500 (mph airspeed).