We need to get the flight directions of that flight, what was its rate of climb, what was its airspeed, what was the point of apex for the cruise. Most aircraft actually climb up and then throttle back for the best altitude, plus one does have to remember the earth isn’t flat either.
So aircraft are actually flying from a perspective of a person on the ground a parabolic flight pattern. They climb up and throttle down.
Now anyone with more detailed info please stand up now, I’m not that knowledgeable but that is what I have heard.