Flight crew incapacitation involving a Beech Aircraft Corp B200C, VH-AMR, 80 km south of Coolangatta, New South Wales, on 22 March 1994

The pilot reported that whilst in level flight at Flight Level 200 (FL200) at approximately 0910 EST (Eastern Standard Time), he began to feel pain in the lower left of his abdomen. He then began feeling airsick, and asked the Flight Sister for a sick bag. Shortly after, he lost consciousness. The Flight Sister then administered oxygen to the pilot and swabbed his face with a damp cloth, until he regained consciousness about two minutes later.

The pilot stated that after regaining consciousness he initiated the oxygen mask drill, declared an emergency to Brisbane control, and directed the Flight Sister to occupy the copilot's seat and to check all radio communications and directions. The pilot said he carried out descent and approach checks two or three times and requested position information from Brisbane Control to cross check his own interpretation of his position. The pilot stated that he used the autopilot until on short final, as he was fearful of lapsing into unconsciousness again. The aircraft was diverted to Coolangatta, and landed on runway 14.

Medical investigation concluded that the most likely cause of incapacitation was expansion of bowel gas in a full colon and stated that abdominal discomfort resulting from this condition can lead to unconsciousness. Although the cabin altitude was 4000 feet the change in pressure would have been sufficient to cause considerable bowel gas expansion. The pilot said he had been on a high fibre diet which predisposed towards formation of bowel gases.