Flight crew incapacitation involving a Airbus A320-211, VH-HYE, 463 km east of Perth Aerodrome, Western Australia, on 25 February 1998

The Airbus A320 was enroute from Sydney to Perth when approximately 250 NM east of Perth, the co-pilot reported that he had a sudden onset of very strong cramp-like pain. He later reported that he had no prior discomfort or warning. The pain developed into very strong waves of lower stomach and right-side pain. As the pain intensity increased, the co-pilot could no longer remain seated and gained slight relief only by standing. The co-pilot was so incapacitated by the pain that he could not perform his duties. The crew decided not to divert to Kalgoorlie because it was an unfamiliar airfield and there would be increased workload for the pilot in command because of the lack of ATS facilities. Operations at Kalgoorlie are conducted under the mandatory broadcast zone (MBZ) procedures.

The pilot in command declared a medical emergency to Melbourne ATC and the aircraft was cleared for a direct track to Perth and received priority processing from Perth ATC. An ambulance was arranged to meet the aircraft on arrival. Because the co-pilot could neither sit or lie down, the crew decided that he would occupy the forward toilet compartment from the top of descent into Perth. The co-pilot used the handgrips and packing provided by the purser to support and brace himself during the descent and landing. The pilot in command engaged the autoland system and the aircraft landed without further incident. The co-pilot was transported to hospital by the waiting ambulance.

The co-pilot was later diagnosed as having kidney stones. He had no known previous history of the condition.