CHARTER ACFT LANDS AFB INSTEAD OF GA ARPT.

Narrative

I WAS SERVING AS SIC ON A FLT FROM SAN TO IPL. OUR IFR CLRNC TOOK US TO POGI VOR; DIRECT IMPERIAL VORTAC; DIRECT TO IMPERIAL ARPT. WHEN WE WERE 20 DME FROM IPL; I ASKED THE CAPT IF HE WANTED TO CANCEL IFR AND GO DIRECT TO IPL ARPT. HE SAID YES; SO WE PROCEEDED. I OBTAINED UNICOM INFO AT THIS TIME AND WAS ADVISED TO USE 'R TFC; RWY 32.' ABOUT 10 MI (RNAV) FROM THE ARPT; WE SAW WHAT WE THOUGHT WAS IMPERIAL. THE CAPT SAID HE WAS GOING TO MAKE A L BASE ENTRY AS HE DSNDED. I CORRECTED HIM AND TOLD HIM WE SHOULD OVER-FLY THE ARPT AND ENTER A R DOWNWIND. THE CAPT DID SO AT ABOUT 3500 FT AGL. DSNDING ON THE DOWNWIND ON FIND; I NOTICED MIL JET TFC LNDG ON A CONVERGING RWY 26. ON ABOUT A 1 1/2 MI FINAL; I TOLD THE CAPT TO GAR BECAUSE OF THE TFC ON THE OTHER RWY. THE CAPT IGNORED ME; EVEN AFTER I POINTED OUT THE TFC (MULTIPLE MIL JET). I KNEW SOMETHING WAS WRONG AND WE SHOULD NOT LAND GIVEN THE CIRCUMSTANCES. AFTER STOPPING THE ACFT; I REALIZED WE HAD LANDED AT EL CENTRO MIL BASE. WE FILLED OUT THE APPROPRIATE RELEASE PAPERS AND WAIVERS AND LEFT FOR OUR DEST OF IPL; 4 MI BEYOND EL CENTRO. FACTORS LEADING TO THIS MOST EMBARRASSING EVENT: UNFAMILIAR AREA AND I WAS VERY TIRED; AS I HAD LITTLE SLEEP THE PREVIOUS NIGHT. WE WERE LOOKING FOR A RWY 32 WITH ANOTHER RWY XING THE 'A INTXN.' WHEN WE SAW THE 32 AT EL CENTRO; WE THOUGHT WE SAW WHAT WE WANTED TO SEE -- 32 AT IPL. A DEG OF STRESS BTWN ME AND THE CAPT STARTED TO BUILD WHEN I CORRECTED HIS ARPT PATTERN ENTRY AND CONTINUED TO A POINT WHERE HE IGNORED MY 'GAR' COMMAND. WE CANCELLED IFR TO AN UNFAMILIAR ARPT WHEN WE THOUGHT WE SAW THE FIELD. IF WE COMPLETED THE IFR PROC TO A LNDG; WE WOULD NOT HAVE MADE THIS ERROR. THE 4 1/2 MI PROX OF THE 2 ARPTS WITH SIMILAR RWY LAYOUTS HAVE FOOLED LOTS OF PLTS AS ATTESTED BY THE TWR OPERATORS AT EL CENTRO.IF WE HAD MADE A GAR; I AM CONVINCED THAT IT WOULD HAVE OCCURRED TO BOTH OF US THAT WE WERE AT THE WRONG ARPT! ON THE WAY HOME; THE AIR TFC CTLR ASKED IF WE COULD GIVE A MIN OF 250 KTS BELOW 10000 FT ON OUR DSCNT TO SAN. I ADVISED THAT WE COULD NOT (I WAS CONCERNED ABOUT TURB) AND WAS ASSIGNED A HDG TO ALLOW FASTER TFC TO PASS. THE CAPT SAID (TO ME) HE COULD GIVE '250-260 KTS; NO PROBLEM.' THIS TIME I CHALLENGED HIS JUDGEMENT AND INSISTED HE SLOW AND TURN TO ASSIGNED HDG. HE COMPLIED -- MORE STRESS! WE ENCOUNTERED LIGHT CHOP N OUR DSCNT. THIS IS NOT THE FIRST TIME OUR CREW CONCEPT HAS FAILED. I WILL DECLINE TO FLY WITH THIS CAPT AGAIN.