hi everybody;
this is my first message to this forum...it looks like a wide range participated forum that I felt myself in a heaven
so first of all best wishes for everyone...
my question;
I am speaking for airliners;
I need to know that is there a rule of thumb about to select the best cruise altitude due to the range...
For ex., for normal condition (all factors are average; weight, weather, time, etc); we have a range about 1000 km, do we need to climb to 37000 ft (or lets say around 33000 ft)...or what would your answer for 500 km. is there a min range to think to climb to 33000 ft?
I have limited data, associated with a B757, and according to that data, the airliner needs to fly 125 nm (231 km) to reach the 37000 ft and another 130 nm (240 km) to descent from that altitude; so the sum is about 470 km. I will base my research on this data and I try to figure out how many additional range would make the flilght economic for flying at this altitude...
other words; can we speak about a start point of range to be able to use the high cruise altitude ?
sorry about the long message but I hope it is sufficiently understandable
Enis