The guys at Warnervale used to use a C182 for PJing. Dunno whether they still use it or indeed still operate. Try the phone book or yellow pages online (Central Coast, NSW). In a C185 I used to use 18" and 2000 rpm for descent, but I would suggest ALWAYS using the power setting that you are told to use by the owner or operator, after all, it is his a/c.