Lateral Slope Qualification
GM, this is the qual test standard that the US Army applied to the UH-60 model line: For lateral slope landings, up to the limit ( in this case it was 15 degrees ) full lateral control is allowed. In fact for the left wheel up slope for that machine, the cyclic was on the stop with the right main about 6-12 inches off the down slope. We dropped it in with the stick on the stop and the Army approved it. Right wheel up slope had adequate control all the way to left wheel touchdown. If you are interested in why there is a difference, send me a PM.
Oleo settling: Not theory, but reality. The slope is measured with a protractor/level on a straight board or similar surface. In the above case it was 15 degrees. Once the landing is complete, the controls centered and the shutdown is accomplished, the roll attitude will indicate 2-3 degrees higher, and that is somewhat dependent on vertical CG as well as oleo design/gear geometry. I'm not familiar with the slope limits on the various Puma models, but would guess that a qualification flight test to whatever their limits are, has been accomplished in a somewhat similar manner to the above. Same oleo compression effects would be expected.
Would crosswind etc impact the results? Certainly. How then are these limits to be applied? Excellent question, as no pilot in the field has any way of eyeballing a slope and knowing whether it is within the approved envelope. The answer is in training the pilot in the procedure on a real measured slope so that he will know and be familiar with the aircraft and control system behavior under the conditions of maximum slope. Not sure the simulators are up to this yet.