Ok aparently i didnt do a great job at explaining so ill try again. Flat earhers very often use the earth curvature calculator here and point out a vast drop that they then ask "wheres the missing drop". When using the metabunks curvature calculator they enter a distance. But this distance you enter isnt the distance as google maps would present it. Basically your curvature calculator shows quite a drop that isnt whats matching up with reality because they enter the curvature line where it should be the line of sight - simply because they can look up the distance along the curve but not the direct line. Would it be possible to get the calculator revised so you enter the distance along the curvature - the google maps distance, and the hight of the viewer and it calculates the right amount of hidden ? As it is now its being used wrong thus they get the wrong result as the line of sight cant be looked up. Im afraid im not very good with these kind of things.

For anything under 200 miles these distances are essentially the same. But if you click on "Advanced" it will calculate it using the curve (great circle) distance. https://www.metabunk.org/curve/?d=200&h=1000&r=3959&u=i&a=a&fd=60&fp=3264 The difference there, with 200 miles distance viewed from 1,000 feet up, is just 3.28 miles vs. 3.29 miles. So there's no great benefit to using the great circle distance.

The problem when using these formulas to calculate the apparent curvature works, but ONLY regarding a full circumference path. If your position between points A and B lie on an oblique angle, (one not parallel to the diameter), the curvature can be less than 2" per mile squared.

Your objection makes no sense. The calculator figures the distance of a line between A and B that grazes the surface at the horizon. There's no such line as "the diameter". If you'd like to explain, please draw a diagram.