T154 / B752, en-route, Uberlingen Germany, 2002 (LOS HF)

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Summary

On 1st July 2002, a Russian-operated Tu154 on a passenger flight collided at night with a cargo Boeing 757-200 over Überlingen, Germany with the consequent loss of control of both aircraft and the death of all occupants. The collision occurred after an ATC control lapse had led to a conflict which generated coordinated TCAS RAs which the B757 followed but the TU-154, in the presence of a conflicting ATC instruction, did not.

Event Details
When	July 2002
Event Type	HF, LOS
Day/Night	Night
Flight Conditions	VMC

Flight Details
Aircraft	TUPOLEV Tu-154
Operator	Not Recorded
Type of Flight	Public Transport (Passenger)
Origin	Moscow/Domodedovo
Intended Destination	Barcelona
Flight Phase	Cruise
	ENR

Flight Details
Aircraft	BOEING 757-200
Operator	Not Recorded
Type of Flight	Public Transport (Cargo)
Origin	Bergamo
Intended Destination	Brussels
Flight Phase	Cruise
	ENR

Location
Approx.	Over Uberlingen, Germany at 34,890 feet amsl
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General
Tag(s)	Flight Crew Training Aircraft-aircraft collision Safety pilot present Inadequate Aircraft Operator Procedures Inadequate ATC Procedures Ineffective Regulatory Oversight

HF
Tag(s)	Procedural non compliance ATC clearance error

LOC
Tag(s)	Collision Damage

LOS
Tag(s)	TCAS RA Mis Flown Required Separation not maintained ATC Error Mid-Air Collision

Safety Net Mitigations
Malfunction of Relevant Safety Net	No
TCAS	Available but ineffective

Safety Net Mitigations
Malfunction of Relevant Safety Net	No
TCAS	Effective
STCA	Available but ineffective

Outcome
Damage or injury	Yes
Aircraft damage	Hull loss
Non-aircraft damage	Yes
Fatalities	Most or all occupants

Causal Factor Group(s)
Group(s)	Aircraft Operation Air Traffic Management

Safety Recommendation(s)
Group(s)	Aircraft Operation Air Traffic Management

Investigation Type
Type	Independent

Contents 1 Description 2 Synopsis 3 Related Articles 4 Further Reading

Description

On 1st July 2002, a Tu-154 collided with a B757 over Überlingen, Germany, following an ATC control lapse and failure of the TU154 to follow the coordinated TCAS RA guidance.

Synopsis

This is an extract of the synopsis from the official report into the incident published by the German Federal Bureau of Aircraft Accidents Investigation (BFU):

"…On 1 July 2002 at 21:35:32 hrs a collision between a Tupolev TU154M, which was on a flight from Moscow/Russia to Barcelona/Spain, and a Boeing B757-200, on a flight from Bergamo/Italy to Brussels/Belgium, occurred north of the city of Überlingen…Both aircraft flew according to IFR…and were under the control of ACC Zurich. After the collision both aircraft crashed into an area north of Überlingen. There were a total of 71 people on board of the two airplanes, none of which survived the crash.

The following immediate causes have been identified:

• The imminent separation infringement was not noticed by ATC at the time. The instruction for the TU154M to descend was given at a time when the prescribed separation to the B757-200 could not be ensured anymore.
• The TU154M crew followed the ATC instruction to descend and continued to do so even after TCAS advised them to climb. This manoeuvre was performed contrary to the generated TCAS RA.

The following systemic causes have been identified:

• The integration of ACAS/TCAS II into system aviation was insufficient and did not correspond in all points with the system philosophy. The regulations concerning ACAS/TCAS published by ICAO and as a result the regulations of national aviation authorities, operations and procedural instructions of the TCAS manufacturer and the operators were not standardised, incomplete and partially contradictory.
• Management and quality assurance of the air navigation service company did not ensure that during the night all open workstations were continuously staffed by controllers.
• Management and quality assurance of the air navigation service company tolerated for years that during times of low traffic flow at night only one controller worked and the other retired to rest.

The Report's lengthy conclusions, beginning on page 107, detail the institutional and organisational failings which contributed to the accident (see Further Reading).

Related Articles

• Loss of Separation

Further Reading

For further information, see the full BFU Accident Report and the Appendices to that report which include the CVR transcripts, FDR traces, and reconstruction of the event.