#### Roy Holmes

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Table 1548 inputs ambient density (slugs/ft^3) and outputs a scalar on "corrected" shaft torque. For 10K feet, 3 up from the bottom, the value of the scalar is 0.735. That would be fine except it is a scalar on "corrected" torque, not actual torque. With that value, torque in a helicopter at 10K feet is around 0.54 of sea level.

Corrected torque factor should be sqrt(sigma) not sigma. If you replace the values in 1548 with their square root the drop in torque with altitude now exactly follows the density ratio.

This is another example of where the MS engineers did not understand what "corrected" values mean when constructing the stock turbine tables.

I have been working on what these values should be in all the turbine tables and will post on the subject in the near future.

Roy