B737-800
Air Traffic Control Fully Certified
Situational Awareness; Confusion; Communication Breakdown
ATC Issue All Types; Airspace Violation All Types; Deviation / Discrepancy - Procedural Published Material / Policy
General None Reported / Taken
Procedure; Human Factors
KOA Tower called me for a release on a B737. I issued a departure clearance of 'Depart heading 350 until joining V11; released your discretion Air Carrier...'.  The Air Carrier aircraft was inbound on the ILS17 Approach. The KOA Tower Controller then questioned this clearance by asking if I really wanted to send the departing aircraft at the inbound aircraft. I replied that 'released your discretion' meant that they needed to provide visual separation or the pilots had to provide visual separation between the aircraft or else don't release the departure until the arriving aircraft has landed. The heading of 350 insured IFR separation would be provided after the use of visual separation to protect for the missed approach. The LOA with KOA allows KOA Tower to provide visual separation between referenced aircraft; in this case the B737 and the other Air Carrier. When the B737 checked in on my frequency the aircraft was about six miles south of the airport out of 3;500 FT. When I asked the pilot why he was so far south he replied that the Tower had issued him Runway (17) heading and then; just before being switched; was issued a heading of 350 leaving 3;000 FT to join V11. By this time the aircraft was already past the point where it could join the airway and had now become a factor with another aircraft inbound to KOA from the northwest as well as was crossing over the missed approach fix for the ILS 17 Approach. KOA Tower must be staffed with competent controllers. I would recommend that the FAA take over the Tower and make the airspace surrounding the Tower Class Charlie airspace. This airport handles way too many air carriers and passengers; as well as a mix of military and general aviation aircraft; to remain a Contract VFR Tower
HCF Controller expressed concern regarding the competance of the 'Contract ATC Controllers' at KOA Tower; citing a recent example of a clearance issued that was not understood.