PLT DIZZINESS AND SLEEPY SENSATION CAUSES RETURN LAND.

Narrative

ON RETURN LEG OF A SOLO XCOUNTRY TRAINING FLT; AT CRUISE ALT; I HAD A SHARP DIZZINESS SENSATION; FOLLOWED BY A SLEEPY FEELING. SUPPLEMENTAL OXYGEN WAS IN USE AT THE TIME; SO I CHKED CONNECTIONS AND FLOW. FEARFUL OF SOME KIND OF CONTAMINATION OF PORTABLE OXYGEN SYS; I DISCONTINUED USE AND DSNDED TO 8500 FT MSL. I BEGAN FEELING A LITTLE BETTER BUT STILL FELT TIRED. DECIDED TO LAND AT WINSLOW; AZ; TO GET SOMETHING TO EAT (HADN'T EATEN SINCE EARLY AM). HAD A MICROWAVE MACARONI MEAL (ARPT RESTAURANT CLOSED) AND SOME WATER. I BEGAN TO FEEL BETTER AND PREPARED TO CONTINUE BACK TO PRESCOTT; AZ. WHILE PERFORMING PRETKOF CHKS; FATIGUE FEELING BEGAN TO COME BACK; BUT DECIDED IT WASN'T TOO BAD TO FLY. CLBING OUT; THE FEELING INTENSIFIED A BIT; SO I OPENED ALL THE VENTS AND WINDOW. APPROX 15 MINS AFTER TKOF; I REALIZED HOW LETHARGIC I WAS BECOMING. I MADE A 180 DEG TURN BACK TO WINSLOW AND TRIMMED ACFT FOR 500 FPM DSCNT. I WAS HAVING A HARD TIME CONCENTRATING; AND PERFORMED EVERYTHING ON CHKLISTS STEP-BY-STEP. I FELT A LITTLE BETTER AS I STARTED TO DSND; BUT DIZZINESS BEGAN TO RETURN DSNDING THROUGH 7000 FT MSL (ABOUT 1000 FT ABOVE TFC PATTERN ALT). THE SLEEPY FEELING RETURNED AND I MAY HAVE BLACKED OUT FOR A SECOND OR TWO; WHICH IS WHEN I DECLARED AN EMER OVER CTAF AND ASKED FOR EMER EQUIP. I WAS UNSURE IF A SAFE LNDG WAS POSSIBLE AND SUSPECTED CARBON MONOXIDE POISONING WHEN MY FINGERS BEGAN TINGLING. ANOTHER PLT ON THE GND AT WINSLOW TOLD ME THE WINDS AND SUGGESTED RWY 22. AS I DSNDED ON DOWNWIND; I BEGAN TO FEEL A LOT BETTER AND MADE A NORMAL LNDG. AN AMBULANCE WAS WAITING ON THE RAMP FOR ME WHEN I TAXIED IN; AND I WAS TAKEN TO THE HOSPITAL. THE DOCTOR IN WINSLOW SUGGESTED THAT IT MIGHT HAVE BEEN THE FLU; AGGRAVATED BY NOT EATING AND POSSIBLE HEAT EXHAUSTION. ALL BLOOD TESTS SHOWED NOTHING ELSE. I HAD INTENDED TO EAT SOMETHING EARLIER IN THE DAY AT MY ORIGINAL DEST (DURANGO; CO); BUT NO RESTAURANT WAS EVIDENT THERE EITHER. IF I HAD KNOWN THAT; I WOULD HAVE BAGGED MY LUNCH THAT DAY. GET-HOMEITIS WAS ALSO A FACTOR IN DEPARTING WINSLOW; BUT AS I REALIZED HOW MY PERFORMANCE WAS DEGRADING AND THE DANGER OF CONTINUING; I MADE THE RIGHT DECISION TO TURN BACK.