If you're interested---
up until about 40 years ago, our then Department of Civil Aviation (who knew that they knew everything that was possible to know about aviation) required that any new type coming into the country had to be flight tested to establish it's takeoff and landing performance. They would not accept that the FAA approved figures for the PA22 (for example) were at all reliable.
The flight test data was then crunched and P charts were produced for takeoff and landing.
The attached ones are for a PA22-160 Tripacer. Basically they were for a level, short dry grass strip. Allowance could be made for pressure altitude, temperature, weight, and head/tailwind.
Takeoff was from a standing start, flaps 0, climb at Takeoff Safety Speed to 50ft.
The landing was based on the stated minimum speed in a power off glide from 50 ft. and maximum braking.
The distances obtained were then increased by 15% (ever conservative, our DCA).
Of course, these had to be carried in an approved Flight Manual in the aircraft. That type of Flight Manual was purely an Australian thing and bore no relationship to anything else around the world. Talk about creating an empire to protect jobs!
If you can't blow these up enough, I can post larger ones.
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