Medium Large Transport
Conflict Airborne Conflict
Flight Crew FLC complied w / Automation / Advisory; Flight Crew Took Evasive Action
Airspace Structure
We were in close proximity to IWA; our intended landing airport.  We were given a heading of approximately 270 and then told by Phoenix approach we had traffic at our 12 o'clock contact IWA tower and cleared for the visual approach.  Immediately after this instruction we received an RA telling us to climb.  The Captain disconnected the autopilot and complied with the original climb order.  I made a radio call to Approach and told them we were responding to an RA.  During the climb we received course reversal commands telling us to then Descend; Descend.   Approach then instructed us to turn right.  After the RA was complied with we reported that we were returning to course and switched over to IWA tower.  I never got visual on the intruding aircraft.  The jumpseater reported seeing the aircraft and said it was very close.  There is a practice area for aerobatic aircraft very close to the approach corridor for IWA.  I believe this practice area should be moved further south to avoid conflicts.
The reporter states the event occurred near VPREN (visual point renaissance) and was likely caused by rapidly climbing aerobatic aircraft. Reporter is not sure of the location of the aerobatic box that they may have been departing.
Air Carrier First Officer experienced a TCAS RA at 5;000 feet descending east of IWA. The RA changed from a climb to a descend but the aircraft involved was not seen. Reporter believes the aircraft involved was returning from an aerobatic practice box.