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Old 27th November 2007 | 15:12
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delta3
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From: Belgium
Max performance take off

Topendtorque


Some results from the desktop world:

Simulation of power curve of a R44-I near MTOW at ISA conditions
Calculated output MR HP. To convert this in Engine HP, one needs to add all mechanical losses plus the TR power. At low speeds where the TR needs to produce approx 500N in this scenario torque I think that the max engine HP of 205 allows for approx 165 MR HP (=red horizontal line).

As Shawn pointed out this graph also does not convert to fuel flow so that for optimal economic speeds it is only approximative.


The results are :




Possible interpretations:

Between IGE and OGE there is 23 MR HP difference, what translates to 30 engine HP so 3 inches. To be added to that is a required acceleration which probably adds 1 inch. This leads to 4 inches. I took 3 ft as IGE instead of 0ft this could explain the difference of 1 inch.

With respect to MP take off the max setting allows for 300 ft/min from 10-15 knts onwards, but again probably one inch margin is needed which translates to a 15-20 knts range.

Does that make any sense ?

d3
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