Narrative:

While tracking to the navasota VOR (approximately 15 NM southwest) at an altitude of 5700 ft MSL, I noticed brenham (11R) airport off of my left wing. Soon after this point, I became dizzy, disoriented, and unable to hold an altitude or heading. I immediately opened a window and started a descent, while also making a turn to the left to relocate 11R airport. After descending to approximately 1000 ft MSL and not being able to locate 11R airport, I dialed in the college station VOR and started tracking inbound on the 330 degree radial. My condition continued to deteriorate and simple tasks became very difficult to perform. I was experiencing tunnel vision and a loss of ability to judge time and distance. I made a radio call to easterwood tower requesting to land. However, I was much farther from the airport than I thought. After realizing this, and feeling like I was close to passing out, I decided that I had to land the plane as soon as possible. I found the first suitable field, made sure that the plane was heading into the wind, and landed the airplane safely. No damage was sustained to myself or the aircraft. My health has always been good, and I felt very good physically before the flight and during the flight until the incident occurred. The WX conditions were excellent and were not a factor in the incident. Looking back, I can't think of anything that I would have done differently. It was the correct decision to land the plane when I did, otherwise the results would have been much worse. The symptoms that I suffered from were consistent with carbon monoxide poisoning, but the exact cause has yet to be determined. Callback conversation with reporter revealed the following information: reporter stated that after the incident he was examined by his doctor which included blood work and the result was negative. Although he felt somewhat under the WX for a couple of weeks following the incident, he is feeling fine now and is back to flying with no restrs. The aircraft also has a clean bill of health.

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Original NASA ASRS Text

Title: A C152 PLT, WHILE CRUISING AT 5500 FT, BECAME ILL. UNABLE TO FLY THE ACFT HE ELECTED TO LAND IN A NEARBY FIELD.

Narrative: WHILE TRACKING TO THE NAVASOTA VOR (APPROX 15 NM SW) AT AN ALT OF 5700 FT MSL, I NOTICED BRENHAM (11R) ARPT OFF OF MY L WING. SOON AFTER THIS POINT, I BECAME DIZZY, DISORIENTED, AND UNABLE TO HOLD AN ALT OR HDG. I IMMEDIATELY OPENED A WINDOW AND STARTED A DSCNT, WHILE ALSO MAKING A TURN TO THE L TO RELOCATE 11R ARPT. AFTER DSNDING TO APPROX 1000 FT MSL AND NOT BEING ABLE TO LOCATE 11R ARPT, I DIALED IN THE COLLEGE STATION VOR AND STARTED TRACKING INBOUND ON THE 330 DEG RADIAL. MY CONDITION CONTINUED TO DETERIORATE AND SIMPLE TASKS BECAME VERY DIFFICULT TO PERFORM. I WAS EXPERIENCING TUNNEL VISION AND A LOSS OF ABILITY TO JUDGE TIME AND DISTANCE. I MADE A RADIO CALL TO EASTERWOOD TWR REQUESTING TO LAND. HOWEVER, I WAS MUCH FARTHER FROM THE ARPT THAN I THOUGHT. AFTER REALIZING THIS, AND FEELING LIKE I WAS CLOSE TO PASSING OUT, I DECIDED THAT I HAD TO LAND THE PLANE ASAP. I FOUND THE FIRST SUITABLE FIELD, MADE SURE THAT THE PLANE WAS HEADING INTO THE WIND, AND LANDED THE AIRPLANE SAFELY. NO DAMAGE WAS SUSTAINED TO MYSELF OR THE ACFT. MY HEALTH HAS ALWAYS BEEN GOOD, AND I FELT VERY GOOD PHYSICALLY BEFORE THE FLT AND DURING THE FLT UNTIL THE INCIDENT OCCURRED. THE WX CONDITIONS WERE EXCELLENT AND WERE NOT A FACTOR IN THE INCIDENT. LOOKING BACK, I CAN'T THINK OF ANYTHING THAT I WOULD HAVE DONE DIFFERENTLY. IT WAS THE CORRECT DECISION TO LAND THE PLANE WHEN I DID, OTHERWISE THE RESULTS WOULD HAVE BEEN MUCH WORSE. THE SYMPTOMS THAT I SUFFERED FROM WERE CONSISTENT WITH CARBON MONOXIDE POISONING, BUT THE EXACT CAUSE HAS YET TO BE DETERMINED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THAT AFTER THE INCIDENT HE WAS EXAMINED BY HIS DOCTOR WHICH INCLUDED BLOOD WORK AND THE RESULT WAS NEGATIVE. ALTHOUGH HE FELT SOMEWHAT UNDER THE WX FOR A COUPLE OF WKS FOLLOWING THE INCIDENT, HE IS FEELING FINE NOW AND IS BACK TO FLYING WITH NO RESTRS. THE ACFT ALSO HAS A CLEAN BILL OF HEALTH.

Data retrieved from NASA's ASRS site as of July 2007 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.