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FROM : AIRBUS FLIGHT SAFETY DEPARTMENT TOULOUSE
TO : ALL AIRBUS OPERATORS / ATTN. : FLIGHT SAFETY
SUBJECT: IBERIA FLIGHT IB6463 ACCIDENT IN QUITO, EQUADOR
PREVIOUS REF : IBE IB6463 AIT N°1 dated 12 November 2007
This AIT is an update of AIT IB6463 N°1 regarding the A340-600 accident during landing on runway 35 at Quito, Ecuador, on the 09th of November 2007 at 17:10 local time.
The data which follows has been approved for release by the commission of investigation led by the Ecuador Investigation Authorities.
The analysis of available data, including the accident recorderas (DFDR & CVR),
indicates the following sequence of events.
IB6463 was approaching on ILS 35 to Quito airport. Latest reported information to the crew during the final approach were:
- wind 170/06;
- visibility 3000m;
- wet runway.
The Captain was the Pilot Flying (PF).
Quito runway 35 altitude is 9198ft. The total runway length is 3120 m. The Landing Distance Available (LDA) is 3120 m. The runway is equipped with a PAPI. However this runway has an ILS displaced threshold of 510 m (remaining LDA for ILS approach is then 2610 m).
The CVR records confirm the crew intent was initially to follow the ILS until sufficient visual references were available, then to leave the Glide Slope to visually capture and follow the PAPI path and use the full runway for landing.
The approach was performed with both AP1&2 engaged in LOC and GLIDE track
modes, A/THR engaged in managed speed mode. Till touchdown, A/THR maintained the VAPP. For final approach, the aircraft was configured to land (gear down, auto-brake set to HIGH, ground spoilers armed, flaps fully extended). Landing weight was 249t, Vapp 151 kt. Given the altitude and the tailwind, the True Air Speed was 181kt and the Ground Speed 189kt.
While AP 1+2 were engaged, the aircraft remained stabilized on the LOC and GLIDE.
Runway 35 was in sight just prior to minimum, DA(H) being 9850ft(652ft).
AP 1+2 were disconnected at the minimum. The PF applied nose-down stick inputs to reach the PAPI flight path. This resulted into an increased rate of descent above 1400ft/mn between 450ft and 150ft radio-altitude. The GPWS "SINK RATE" warning was triggered at 270ft radio-altitude, it was followed by transient nose-up inputs from the PF.
The "SINK RATE" warning was triggered again below 50ft AGL.
The touch-down occurred at about 200m after the full runway threshold (remaining distance was 2920 m).
The landing was extremely hard (more than 3g vertical acceleration, about 19ft/sec 1100ft/mn), which lead to:
- Breakage of the lower articulation link of both Main Landing Gear (MLG);
- Abrupt derotation of both bogie beams;
- Burst at impact of all 4 MLG front wheels;
- And damage of the wiring looms of RH and LH boogie proximity sensors that are used to detect the GROUND condition hence allowing engine thrust reversers deployment.
As a consequence of the 4 MLG front wheels burst, the AUTO BRAKE function was lost.
FROM : AIRBUS FLIGHT SAFETY DEPARTMENT TOULOUSE
TO : ALL AIRBUS OPERATORS / ATTN. : FLIGHT SAFETY
SUBJECT: IBERIA FLIGHT IB6463 ACCIDENT IN QUITO, EQUADOR
PREVIOUS REF : IBE IB6463 AIT N°1 dated 12 November 2007
At touchdown, engine throttles were retarded to idle thus A/THR disengaged, and the ground spoilers deployed immediately.
The thrust reversers were selected but did not deploy because the GROUND condition monitored by the Engines Control Computers was not fulfilled due to the above mentioned sensors loom damage. For the same reason, engines stayed at FLIGHT IDLE instead of GROUND IDLE.
Full manual braking was applied 5 seconds after touchdown for the whole rollout. The average deceleration achieved during this landing phase was 0.15g. It was consistent with:
- the wet condition of runway;
- the 4 MLG front wheel tyre burst;
- the non-deployment of the engine thrust reversers.
The runway overrun occurred at 85kt in a right turn sideslip attitude resulting from right rudder pedal inputs. The aircraft finally came to a rest at about 200m from the runway end. All passengers and crew members were safely evacuated.
At this stage of the investigation, Airbus reminds operators to comply with Standard Operating Procedure to achieve stabilized approach conditions. Go-around must be initiated if the stabilized conditions are not met at defined altitudes.