Attached are a couple of pages from my AFM regarding take off performance, flaps up, over a 50' barrier. The one on the left is "FAA approved", and only for max gross weight. The one on the right is from (shall we say) "Piper", and is used for various weights. I would think that the "Piper" graph when at gross weight should equal the "FAA" graph, but they don't. They are different by hundreds of feet. I am curious, why? What am I missing?
Note that there is also a similar thing for Landing, but the differences there are minor in comparison.
Note that there is also a similar thing for Landing, but the differences there are minor in comparison.