The trailer mounted turbine unit must be operated only in a true level state. There are at least two sets of inclinometers that measure the pitch and roll of the trailer - one set at each end, as the unit can 'bend' under it's weight, hence the need for eight supports. The supports can be hydraulically extended and retracted, but actual extension position is not known. Only limit switches to indicate max or min extension. I had thought of a PID loop for each leg, but since each leg's position will affect the pitch and roll to at least one other leg and with only two sets of inclinometers, this can't work - not in it's purest form at least. Any thoughts as how to approach this problem ?