REAL jump/landing building

This is by far the best way.

there are a fairly simple set of calcs that you could use to precisely nail down the sizes, inrun length, angles etc. But honestly, an experienced park builder will be able to eyball it and get it super close to the "optimal" numbers.

Why waste time, when experience can get you a nearly identical result?

Yeah, unfortunately this isn't a very good defense in court when your a resort and getting sued for 20 million dollars.

Well said, well said.

Yup all good info here, to add a little bit, typical jumps, tables, stepdowns, we use a ratio of 2:1, if your deck (lip to sweet spot) is 45ft, your landing should be at least 90ft, in most cases. And the angles of takeoff and landing shoud match, general angles are somewhere around 30-35 degrees. Step ups and step-overs can be a little less of the ratio but same on the angles. Slope/terrain angles add some more math to these factors which in turn will affect spacing between your jumps and or rails in your parks, listen to your terrain.

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