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Hi,
I would like to know if there is a formula to determine the glide ration of a cessna 172.
Based on the graph in the cessna 172 POH, at 4000 ft I can glide 6 NM and at 2500 ft I can glide 4 NM. With only this information, how can I find the glide ration of this particular airplane whether it is 10:1 or 11:1 and so on?
Cheers
A nautical mile is 6080 feet. So
4000 feet is 4000 ÷ 6080 = .66 nautical miles. Therefore the glide ratio at 4000 feet is 6 to .66 which is approximately 9 to 1.
2500 feet is 2500 ÷ 6080 = .41 nautical miles. So, at 2500 feet the glide ratio is 4 to .41 which is also approximately 9 to 1.
If you convert the height given in the POH to nautical miles by dividing by 6080, you will be able to compare the height to the distance flown both in nautical miles.