Narrative:

I was approaching geg on the ILS runway 3 approach. While on the final approach I descended below the GS unintentionally approximately 2-3 mi from the runway threshold. I could see the ground below but did not have the runway in sight. I was notified by tower that radar indicated a low altitude warning. I then noticed that I had flown a full scale deflection below the GS. I made a correction with pitch and power to regain the GS, but in the process drifted to near a full scale deflection to the left of the localizer by the time I saw the runway near the threshold. I was approximately 200 ft to the left of the runway near the threshold. I was able to correct for this and landed long on the runway without further difficulty. Events leading to the problem: on the day of the occurrence, I had already been suffering 2 days from what I thought was a mild cold. That morning, prior to the flight, I felt reasonably well and had taken only 2 aspirin. I had not been using any decongestant, antihistamine or any other medication. I felt strong and did not see any need to postpone the flight. However, when the workload began to increase as I approached the final approach fix, I began having difficulty keeping up with the airplane (a pressurized small transport). The power and airspeed were too high while crossing the FAF. While trying to correct this, I was distracted from my instrument scanning and events were happening rapidly. I found myself trying to catch up with the airplane. When notified by tower that I was too low, I had the ground in sight and was a few hundred ft above the ground. I therefore did not feel any imminent danger and decided to recapture the GS and proceed with the approach. By the middle of that afternoon, I began to feel much more ill and had developed the flu with a low grade fever. I believe that the illness had effected my judgement and reaction time during that flight. Normally I would have done a missed approach under such circumstances and would have been better prepared for the second attempt at the approach. Fortunately I was able to land uneventfully, but the thought of what could have happened still haunts me. The moral: don't fly if you are sick!

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Original NASA ASRS Text

Title: ILLNESS REDUCES PERFORMANCE LEADING TO DSNDING BELOW GS DANGEROUSLY.

Narrative: I WAS APCHING GEG ON THE ILS RWY 3 APCH. WHILE ON THE FINAL APCH I DSNDED BELOW THE GS UNINTENTIONALLY APPROX 2-3 MI FROM THE RWY THRESHOLD. I COULD SEE THE GND BELOW BUT DID NOT HAVE THE RWY IN SIGHT. I WAS NOTIFIED BY TWR THAT RADAR INDICATED A LOW ALT WARNING. I THEN NOTICED THAT I HAD FLOWN A FULL SCALE DEFLECTION BELOW THE GS. I MADE A CORRECTION WITH PITCH AND PWR TO REGAIN THE GS, BUT IN THE PROCESS DRIFTED TO NEAR A FULL SCALE DEFLECTION TO THE L OF THE LOC BY THE TIME I SAW THE RWY NEAR THE THRESHOLD. I WAS APPROX 200 FT TO THE L OF THE RWY NEAR THE THRESHOLD. I WAS ABLE TO CORRECT FOR THIS AND LANDED LONG ON THE RWY WITHOUT FURTHER DIFFICULTY. EVENTS LEADING TO THE PROB: ON THE DAY OF THE OCCURRENCE, I HAD ALREADY BEEN SUFFERING 2 DAYS FROM WHAT I THOUGHT WAS A MILD COLD. THAT MORNING, PRIOR TO THE FLT, I FELT REASONABLY WELL AND HAD TAKEN ONLY 2 ASPIRIN. I HAD NOT BEEN USING ANY DECONGESTANT, ANTIHISTAMINE OR ANY OTHER MEDICATION. I FELT STRONG AND DID NOT SEE ANY NEED TO POSTPONE THE FLT. HOWEVER, WHEN THE WORKLOAD BEGAN TO INCREASE AS I APCHED THE FINAL APCH FIX, I BEGAN HAVING DIFFICULTY KEEPING UP WITH THE AIRPLANE (A PRESSURIZED SMT). THE PWR AND AIRSPD WERE TOO HIGH WHILE XING THE FAF. WHILE TRYING TO CORRECT THIS, I WAS DISTRACTED FROM MY INST SCANNING AND EVENTS WERE HAPPENING RAPIDLY. I FOUND MYSELF TRYING TO CATCH UP WITH THE AIRPLANE. WHEN NOTIFIED BY TWR THAT I WAS TOO LOW, I HAD THE GND IN SIGHT AND WAS A FEW HUNDRED FT ABOVE THE GND. I THEREFORE DID NOT FEEL ANY IMMINENT DANGER AND DECIDED TO RECAPTURE THE GS AND PROCEED WITH THE APCH. BY THE MIDDLE OF THAT AFTERNOON, I BEGAN TO FEEL MUCH MORE ILL AND HAD DEVELOPED THE FLU WITH A LOW GRADE FEVER. I BELIEVE THAT THE ILLNESS HAD EFFECTED MY JUDGEMENT AND REACTION TIME DURING THAT FLT. NORMALLY I WOULD HAVE DONE A MISSED APCH UNDER SUCH CIRCUMSTANCES AND WOULD HAVE BEEN BETTER PREPARED FOR THE SECOND ATTEMPT AT THE APCH. FORTUNATELY I WAS ABLE TO LAND UNEVENTFULLY, BUT THE THOUGHT OF WHAT COULD HAVE HAPPENED STILL HAUNTS ME. THE MORAL: DON'T FLY IF YOU ARE SICK!

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.