A series of atypical circumstances preceded an early morning taxiway landing of a Delta Air Lines Boeing 767 at the Atlanta Hartsfield International airport from Rio de Janeirio on 19 October, according to a preliminary incident report published by the US National Transportation Safety Board (NTSB) on 23 December.
None of the 182 passengers or 11 crew on Delta Air Lines Flight 60 were injured in the incident, which occurred in pre-sunrise darkness and good weather at 06:05 EST that morning, nor was the aircraft damaged, according to the NTSB.
The chain of events that led to the incident appears to have begun during cruise flight, when a check airman in the cockpit became sick and was relocated to the main cabin.
While the nature of airman's medical problem was not identified, the NTSB says the crew notified Delta dispatchers of the situation "and a medical emergency was declared to air traffic control via the company". A decision was made to continue to Atlanta with the remaining two pilots, the NTSB continues.
Inbound to the airport, the air traffic controller handling the flight offered to switch the aircraft's landing runway from 27L to a parallel runway, 27R, via a "sidestep" manoeuvre in order to put the aircraft closer to the terminal for a planned medical evacuation of the sick check airman. The pilots accepted the modified clearance.
Runway layout at Atlanta
With a sidestep, pilots can fly the instrument approach to 27L, manoeuvring to the line up with 27R after sighting the runway visually on the approach.
The instrument landing system for 27R was not operating as it was not the baseline runway for the approach that night. Approach lights for runway 27R were also inoperative due to maintenance being performed.
"The crew landed on taxiway M, located 200ft north of runway 27R," says the NTSB. "After landing on the taxiway, the flight crew taxied to the ramp without further incident."