The accumulators for the AS350 are only there to assist the pilot in getting below 60kts and are dumped of all pressure when you have your hand on the situation and gotten over the lights and horn scaring the living out of you. Not that it is a common problem in the Squirrel anyhow no mater how hard you laugh at the Hyd drive belt they are very reliable. You can put the dual hydraulic system in if you have more money than brains and common sense (eg ADF). And as for the why can't you disable both systems gripe... why shut off both when you have a redundancy system? Like have you ever tried to fly a S76 with both systems off? A: No, as not possible to fly with out hydraulics or turn it off. Jack stall can occur in the AS350 but you have to really load up the hydraulics to do so and why on earth you would want to get into that situation in the first place is beyond me as it really takes a bit to do it and is quite scary when it does freeze up on you.