AT43, vicinity Geneva Switzerland, 2006
AT43, vicinity Geneva Switzerland, 2006
Summary
On 29 March 2006 at about 1 mile from touchdown when in VMC on a night approach to destination Geneva, an ATR 42-300 being operated by Farnair on a cargo flight experienced a sudden electrical fire in the flight deck and an emergency was declared to ATC. Despite this situation the aircraft was able to land normally and vacate the runway via an RET after which it was forced to stop.
Event Details
When
29/03/2006
Day/Night
Night
Flight Conditions
On Ground - Normal Visibility
Flight Details
Aircraft
Operator
Type of Flight
Public Transport (Cargo)
Flight Origin
Intended Destination
Take-off Commenced
Yes
Flight Airborne
Yes
Flight Completed
Yes
Phase of Flight
Descent
Location
Location - Airport
Airport
General
Tag(s)
Inadequate Airworthiness Procedures
FIRE
Tag(s)
Fire-Electrical origin
EPR
Tag(s)
MAYDAY declaration,
RFFS Procedures
AW
System(s)
Electrical Power
Contributor(s)
Maintenance Error (valid guidance available),
Damage Tolerance,
Component Fault in service
Outcome
Damage or injury
Yes
Aircraft damage
Minor
Non-aircraft damage
Yes
Non-occupant Casualties
No
Off Airport Landing
Yes
Ditching
Yes
Causal Factor Group(s)
Group(s)
Aircraft Technical
Safety Recommendation(s)
Group(s)
None Made
Investigation Type
Type
Independent
Description
On 29 March 2006 at about 1 mile from touchdown when in VMC on a night approach to destination Geneva, an ATR 42-300 being operated by Farnair on a cargo flight experienced a sudden electrical fire in the flight deck and an emergency was declared to ATC. Despite this situation the aircraft was able to land normally and vacate the runway via an RET after which it was forced to stop. A significant loss of onboard systems was reported to have occurred due to many CBs tripping. However, because of this, the fire on board had lasted for only a few seconds and external intervention was not necessary to fight the fire.
The Investigation
The Swiss BEA/BFU carried out a Serious Incident Investigation which was published on 8 April 2009. The Findings included the following:
- an earth cable was fitted incorrectly. Its lower terminal was therefore in direct contact with the strand of electrical wiring, whereas there should have been a space of at least 12.5 mm (0.5 in) between these two items.
- The tubular support to which the strand was mounted was deformed; the routing of the bundle of wires modified in this way no longer permitted compliance with the minimum separations required between the structure and other cables.
- The collars used to mount the strand to the tubular structure were not tightened sufficiently.
- The damaged strand contained more electrical wires than the original design because of modifications resulting from application of service bulletins; its diameter had therefore increased.
- It was not possible to determine the precise origin of the assembly defects.
The cause of the occurrence was determined to be “due to an incipient fire caused by a short-circuit following several assembly defects”.
As a result of the occurrence, the aircraft manufacturer conducted an investigation among several ATR 42/72 operators to find out if other cases of incorrect assembly of the same earth cable existed. The results showed that several instances of this fault had been found. On 14 September 2006, EASA issued an AD requiring inspection of all ATR 42/72 aircraft in which the risk of a similar short-circuit resulting from this assembly defect might exist by 31 December 2006. No Safety Recommendations were therefore made in the Final Report.
Related Articles
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- Fire in the Air
- Fire Triangle
- Aircraft Fire Detection Systems
- Aircraft Fire Extinguishing Systems
- Accident and Serious Incident Reports: FIRE
