Question

The altitude of the plane remain
less than​

Answer 1

Answer:

The altitude of the plane remain

less thantoo high and the oxygen becomes too sparse to fuel the engines, too low and the air resistance is greater. This optimum height is linked to the usual weight of a commercial jet – that is, heavier planes would fly lower, and lighter higher.

It would actually be most efficient to be forever climbing, rather than plateau when reaching say, 35,000 feet, cruising altitude, as the weight of the aircraft decreases due to fuel usage and the air thins.

"Each individual aircraft has an optimum altitude (for minimum cost or minimum fuel burn) which will be based on its individual weight," explains Peter Terry, a commercial airline pilot of 30 years.

"Concorde flew at much higher altitudes – 50,000/60,000 feet – where there were no other aircraft and so were able to cruise climb [that is keep climbing]."