Human Failings Underscored In Report of 2002 Mid-Air Collision Over Germany

Air Safety Week, May 31, 2004

Pilots disregarding a coordinated TCAS RA while attempting visual avoidance do so at their peril.

(The full BFU report and appendices may be viewed at www.bfuweb.de/aktuinfo42.htm)

COUNTDOWN TO COLLISION CHRONOLOGY OF THE FATAL JULY 2002 MID-AIR COLLISION OVER GERMANY OF A B757 CARGO AIRCRAFT AND A RUSSIAN TU154

Time (UTC): 21:00

Zurich ACC: Controller begins his shift.

TU154M: - B757-200: - Time (UTC): 21:15

Zurich ACC: The second controller on duty retires to the lounge, leaving just one controller on duty

TU154M: - B757-200: - Time (UTC): 21:18

Zurich ACC: Upper airspace sector modification work under way, with computers in fallback mode.

TU154M: - B757-200: - Time (UTC): 21:23

Zurich ACC: Direct telephone lines to neighboring ATC units no longer available. TU154M: - B757-200: - Time (UTC): 21:29:50

Zurich ACC: - TU154M: - B757-200: Airplane reaches 36,000 ft.

Time (UTC): 21:29:52

Zurich ACC: - TU154M: Aircraft first appears on Zurich ACC radar B757-200: - Time (UTC): 21:30:11

Zurich ACC: - TU154M: PIC contacts Zurich. Airplane is at 36,000 ft. B757-200: - Time (UTC): 21:32:38

Zurich ACC: - TU154M: - B757-200: Aircraft first appears on Zurich ACC radar.

Time (UTC): 21:33:18

Zurich ACC: Distance between two airplanes 27 NM

TU154M: Crew notices for first time on its TCAS display another airplane approaching from the left.

B757-200: - Time (UTC): 21:33:24

Zurich ACC: STCA alarms at Karlsruhe ACC. Karlsruhe controllers make 11 attempts in vain to contact ACC Zurich by telephone.

TU154M: - B757-200: - Time (UTC): 21:34:30

Zurich ACC: - TU154M: - B757-200: Copilot hands over control of the airplane to PIC to go to the lavatory.

Time (UTC): 21:34:36

Zurich ACC: Distance between the two airplanes 10 NM. Closure rate is about 700 knots.

TU154M: PIC says, "Here it is, in sight" (apparent visual contact with B757). Two seconds later, he says, "Look here it indicates zero" (referring to TCAS display and zero altitude difference between the two airplanes). B757-200: - Time (UTC): 21:34:42

Zurich ACC: The two airplanes are 9.94 NM apart.

TU154M: TCAS issues a traffic advisory (TA): "Traffic, traffic." Both PIC and copilot acknowledge, calling out "traffic."

B757-200: TCAS issues a traffic advisory (TA): "Traffic, traffic."

Time (UTC): 21:34:49

Zurich ACC: TU154 crew instructed to descend to 35,000 ft., with reference to conflicting traffic: "Descend flight level 350, expedite, I have crossing traffic."

TU154M: Instruction not acknowledged by crew. However, PIC (acting as pilot not flying) commands in the imperative, "Descend."

B757-200: - Time (UTC): 21:34:56

Zurich ACC: Distance between two airplanes 7.11 NM. Minimum radar separation is penetrated.

TU154M: Control column pushed forward, autopilot switched off, thrust reduced to initiate descend. At same time, TCAS generates resolution advisory (RA): "Climb, climb."

B757-200: TCAS issues a resolution advisory (RA): "Descend, descend." Two seconds later, pilots switch off autopilot and begin descent.

Time (UTC): 21:34:59

Zurich ACC: - TU154M: Copilot says, "It (TCAS) says climb." PIC replies, "He (ACC) is guiding us down." Copilot responds, "Descend?"