Narrative:

Landed at the ism airport without landing clearance. We left ilm just after 10; went to spa; waited for about 2 hours. Left for lal. Just before we got to lal I became very disoriented. Thought we were low on fuel; landed in zephyrhills; fl; topped off the inboard fuel tanks; outboards were full. Departed zph for lakeland; fl. Again became disoriented; could not interpretation the compass or GPS. I was circling around when I saw the ism airport. Decided to land. Until I got on the ground I did not know what airport I had landed at. Had landed without calling the tower. I have about 1500 hours in the B200; just over 15000 hours total time. This was my first trip in this aircraft. The aircraft I regularly fly has a honeywell mfd; with a KLN94 GPS. The aircraft I was flying yesterday has 2 garmin 530's and an avidyne mfd. Also a different autoplt. My first thoughts on the cause for this were the antihistamine I had been taking for a head cold over the wkend. On my drive back (car) to north carolina; I experienced some pain in my left kidney area; also experiencing high fever. Upon my return; called the urologist. After arriving at his office found to have a temperature of 103 degrees. He took x-rays; immediately sent me to hospital. Ended up staying in the hospital for 4 days mainly for the complications of the high temperature. The doctor informed me that the disorientation was probably caused by the high temperature.

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Original NASA ASRS Text

Title: VERY EXPERIENCED BE200 PLT EXPERIENCED DISORIENTATION AND LWOC AT ISM.

Narrative: LANDED AT THE ISM ARPT WITHOUT LNDG CLRNC. WE LEFT ILM JUST AFTER 10; WENT TO SPA; WAITED FOR ABOUT 2 HRS. LEFT FOR LAL. JUST BEFORE WE GOT TO LAL I BECAME VERY DISORIENTED. THOUGHT WE WERE LOW ON FUEL; LANDED IN ZEPHYRHILLS; FL; TOPPED OFF THE INBOARD FUEL TANKS; OUTBOARDS WERE FULL. DEPARTED ZPH FOR LAKELAND; FL. AGAIN BECAME DISORIENTED; COULD NOT INTERP THE COMPASS OR GPS. I WAS CIRCLING AROUND WHEN I SAW THE ISM ARPT. DECIDED TO LAND. UNTIL I GOT ON THE GND I DID NOT KNOW WHAT ARPT I HAD LANDED AT. HAD LANDED WITHOUT CALLING THE TWR. I HAVE ABOUT 1500 HRS IN THE B200; JUST OVER 15000 HRS TOTAL TIME. THIS WAS MY FIRST TRIP IN THIS ACFT. THE ACFT I REGULARLY FLY HAS A HONEYWELL MFD; WITH A KLN94 GPS. THE ACFT I WAS FLYING YESTERDAY HAS 2 GARMIN 530'S AND AN AVIDYNE MFD. ALSO A DIFFERENT AUTOPLT. MY FIRST THOUGHTS ON THE CAUSE FOR THIS WERE THE ANTIHISTAMINE I HAD BEEN TAKING FOR A HEAD COLD OVER THE WKEND. ON MY DRIVE BACK (CAR) TO NORTH CAROLINA; I EXPERIENCED SOME PAIN IN MY L KIDNEY AREA; ALSO EXPERIENCING HIGH FEVER. UPON MY RETURN; CALLED THE UROLOGIST. AFTER ARRIVING AT HIS OFFICE FOUND TO HAVE A TEMP OF 103 DEGS. HE TOOK X-RAYS; IMMEDIATELY SENT ME TO HOSPITAL. ENDED UP STAYING IN THE HOSPITAL FOR 4 DAYS MAINLY FOR THE COMPLICATIONS OF THE HIGH TEMP. THE DOCTOR INFORMED ME THAT THE DISORIENTATION WAS PROBABLY CAUSED BY THE HIGH TEMP.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.