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Saving climb fuel

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Saving climb fuel

Old 7th Sep 2021, 13:30
  #21 (permalink)  
 
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I thought cost index 0 climb was the cheapest when the cost of fuel is higher than the cost of time.
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Old 7th Sep 2021, 13:50
  #22 (permalink)  
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Climbing point to point

BizJetJock

That is consistent with what I found. I found a way to calculate the best speed (least fuel used) to climb from point to point, not from level to level. The max rate climb speed in the flight manual, is the best speed to climb from level to level.
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Old 7th Sep 2021, 14:18
  #23 (permalink)  
 
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Have you seen this? https://ansperformance.eu/library/airbus-cost-index.pdf
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Old 7th Sep 2021, 19:43
  #24 (permalink)  
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Someone has done it

Thank you very much. This is the answer to my original question if someone has done this already. Figure 11 is exactly the concept I'm working on. However, Table 6 says that you use more fuel if you climb directly to target point. That is opposite to what I found. I'll recheck my calculations.
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Old 9th Sep 2021, 13:32
  #25 (permalink)  
 
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Borrow the simulator for a couple of hours. Then see for yourself.
Set your arrival window at 20NM/5000ft to compare as approaches are too variable and thirsty.


Last edited by Deepinsider; 9th Sep 2021 at 13:48.
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Old 22nd Sep 2021, 01:55
  #26 (permalink)  
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No journal is interested?

For a 747-100 starting a climb at 10,000 ft to a higher cruising altitude, the flight manual specifies 290 kts as climb speed. My study shows that B747-100 can climb at 40 kt higher speed and still save fuel. This may apply to other aircraft types as well. I sent this article to 2 journals, AIAA and AST, they both refused to consider it. Does anyone know of a journal that might be interested?
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Old 22nd Sep 2021, 10:53
  #27 (permalink)  
 
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Okay then, show us your sums......
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