calculating climb/cruise/landing
 

Could you please tell me how to calculate climb/cruise/landing according to weight of aircraft. I have completed two successful cycles calculating weight and cost per kg/passenger but for the third cycle of my mathematics assignment, I need to advance to a more realistic approach. Is there a rule of thumb for calculating how long an aircraft (I am using a boeing 737-300) will take to get to cruise height and back down for landing according to weight? I hope to be able to transfer the calculations to a graphical format to show variation.

Cheers for your time in helping me,

Mark