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Old 18th Oct 2008, 19:32
  #34 (permalink)  
Von Klinkerhoffen
 
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If something is in steady state , it is in balence i.e. all accelerations acting on it cancel out . So surely it's a constant climb rate , as opposed to a steady state climb ? For the aircraft too climb , the total upward vertical acceleration i.e the total lift made up of wing lift componant and thrust lift componant , must be greater then the total downward acceleration due to gravity i.e. weight , therefore it cannot be steady state ! Steady state can only be applied to cruise where the aircraft neither climbs or descends , speeds up or slows down.


Krujje , quote:

Furthermore, if the climb velocity is not that great, then there is a good chance that the wings will actually be stalled, which means there will be airflow separation over the wing surface, and that means there will be lots of drag, not no drag. Therefore, the thrust from the engines not only has to act against the weight of the aircraft, but also against a good amount of drag.


Sorry have to disagree , I think you are confusing a stalled wing due to excessive AoA with one that is not producing lift due to insufficient airspeed . In vertical flight , AoA will be such that the wing produces no lift and therefore induced drag will fall to zero , of course all other forms of drag will remain. All upward acceleration will be provided by engine thrust alone acting against weight and the remaining drag....as for a rocket .
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