Rate of climb analysis for a fixed pitch propeller powered aircraft
I did a spreadsheet(.XLSX) of the Snorri Gudmundsson book 'GA aircraft design' on chapter 18 'Performance Climb'. It is quite self
explainatory, but I didn't used column Advance Ratio for the propeller efficiency (that is a cubic polynomial of the ratio for the propeller
of the Cirrus SR22 in the book) .
I inferred efficiency of a fixed pitch propeller at 0.75 for cruise speed at 65% power and 0.7 at max speed, that is a question
of propeller choice explained in the book.
Max ROC speed is at 55 KCAS for my example (A 109sqft aircraft with 950lbs MTOW and a 62BHP VW conversion).
I hope it can help you to choose a powerplant for your design. My interest in that spreadsheet was air density effects with
altitude and temperature on rate of climb, that is always interesting to know about a specific configuration (aircraft and
powerplant choice).
I can answer question about the spreadsheet.
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