WITH TWR CLOSED; AN F900 CPR FLT DEPARTS ON A NIGHT OP VFR FROM KOA PRIOR TO A RELEASE BEING ISSUED BY ZHN CTLR.

Narrative

I WAS FLYING IN THE L SEAT AS PIC; AND THE CHIEF PLT FLEW THE FO POSITION. OUR FLT WAS FROM PHKO (KOA) TO THE UNITED STATES EAST COAST WHICH PUT US AT MAX RANGE WITHOUT A FUEL STOP ON THE MAINLAND. I OBTAINED THE IFR CLRNC FROM ZHN BECAUSE THE TWR AT KONA HAD ALREADY CLOSED. CTR REQUESTED IN THE CLRNC WE GET A TKOF RELEASE FROM THEM BEFORE DEP. WHILE TAXIING OUT I LISTENED TO THE PHKO TWR FREQ FOR AIRBORNE AND GND TFC AT THE ARPT. AT THE DEP END OF THE RWY I ASKED THE FO IF ZHN HAD RELEASED US YET. HE TOLD ME TO TKOF; I ASSUMED WE HAD AN IFR RELEASE. THE PHKO ARPT WAS CAVOK AT THAT TIME; AND I REMAINED IN VFR CONDITIONS AT ALL TIMES. THE FO CONTACTED CTR AT 1000 FT AND THE CTLR INFORMED US WE HADN'T BEEN RELEASED AND TO MAINTAIN 4000 FT AND PRESENT HDG. SHORTLY AFTER THEY PROVIDED US WITH A CLRNC. AT ALL TIMES WE WERE IN VFR CONDITIONS AND CLR OF TFC. I BELIEVE OUR PROB WAS A RESULT OF CREW FATIGUE AND POOR CRM. APPROX 10 HRS BEFORE OUR DEP WE HAD ARRIVED IN KONA AFTER XA09 FLT FROM ASIA. THE REST PERIOD WAS FURTHER REDUCED BY A LONG CUSTOMS CHK; THE NEED TO REPOSITION THE ACFT AND OUR HOTEL ROOMS WERE NOT READY. OUR BODY CLOCK MADE SLEEP DIFFICULT; AND TIME WAS NEEDED TO EAT. THE CREW WAS PRESSURED TO COMPLETE THE MISSION AS QUICKLY AS POSSIBLE BECAUSE OF THE OWNER'S FAMILY EMER. TO FURTHER COMPOUND THE SIT OUR CRM SKILLS WERE NOT UP TO PAR. ALTHOUGH THE CHIEF PLT WAS FLYING THE FO POS; THERE WAS NO MISTAKE HE WAS IN CHARGE. THE PRESSURE OF COMPLETING THE MISSION ASAP; AND THE LACK OF SLEEP MADE AN OPEN DIALOGUE DIFFICULT.