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Britair CRJ7 at Lorient on Oct 16th 2012, overran runway on landing

The French BEA released their final report in French (English version released on Mar 18th 2014) concluding the probable cause of the accident was:

The accident was caused by the crew deciding not to abort the landing although they were not aware either of the degree to which runway conditions were contaminated or of the remaining length of runway available.

Continuing the landing can be explained by:

ˆˆ- Insufficient situational awareness linked to:

* „„Crew performance degraded by fatigue and routine,

* „„Unfamiliarity with safety margins and inadequate TEM training;

- An approach to safety by the operator that did not encourage crews to question their plan of action.

The following factors contributed to the incident:

ˆˆ- The crew’s under-estimation of the meteorological conditions;

- ˆOperational instructions that were sometimes unclear or contradictory, thereby undermining teamwork;

-ˆˆ The characteristics of runway 25, which were also not documented in the Brit Air Operations Manual;

ˆˆ- The organisation of aerodrome operations that contributed to the deviations identified concerning runway 25 not being corrected in a timely manner;

-ˆˆ A lack of common phraseology that would guarantee crews and controllers to have a shared comprehension of the true condition of the runway;

-ˆˆ The organisation of training and checks that prevented the operator from recognising and improving its safety performance;

ˆˆ- Incomplete integration of the risks of fatigue by the airline.

The BEA released safety recommendations to improve runway lighting, retention of water on runway 25, management of threats and errors, professional levels of crew, management of fatigue, clarification of documentation, certification of aerodrome operators and an European action plan regarding runway excursions. A symposium was held by the BEA.

The captain (42, ATPL, 6,910 hours total, 4,025 hours on type) was pilot flying, the first officer (45, ATPL, 5,244 hours total, 3,014 hours on type) was pilot monitoring. The crew prepared for an ILS approach to runway 25 with flaps set to 30 degrees, Vapp was determined to be 140 KIAS. While in contact with the approach controller the approach controller notified the crew that the runway was wet with puddles of water, the preceding aircraft had encountered hydroplaning, the landing was a "little bit complicated". The winds came from 160 degrees at 17 knots gusting up to 26 knots. A few minutes later the controller updated that there were heavy rainshowers at the aerodrome, the visibility reduced to 2000 meters, reiterating the precipitation was serious and repeating the previous aircraft had encountered hydroplaning on landing, and updated the winds from 150 degrees at 17 knots gusting 26 knots (tailwind component of 4 knots).

The aircraft intercepted the localizer at 1900 feet and 180 KIAS with the autopilot engaged, the landing gear is lowered and the aircraft slowed to Vapp with flaps at 30 degrees. Descending through 1500 feet the landing checklist is completed. At 1000 feet AGL the aircraft, according to flight data recorder, flies at 144 KIAS and 4 knots tailwind component, the captain called "stable approach, continue".

At 600 feet the crew establishes visual contact with the runway lights, the windscreen wipers are set to maximum speed, the speed increases to 155 KIAS, the aircraft descends through 400 feet AGL at 154 KIAS, the autopilot gets disconnected at 400 feet. Descending through 200 feet AGL at 147 KIAS the captain annotated "he'll use a rather high airspeed", the first officer agreed. The aircraft crossed the runway threshold at 53 feet AGL and an airspeed of 153 KIAS with a 4 knots tailwind component, the first officer comments visibility is bad, the aircraft was left of the runway center line. 9 seconds after crossing the threshold the main wheels contact the runway about 1130 meters down the runway at a speed over ground of 140 knots. The spoilers automatically extend, thrust reversers are engaged and maximum reverse thrust applied, the aircraft decelerates. About 9 seconds after touchdown the captain comments the aircraft won't stop, 12 seconds after touchdown the aircraft exits the end of the runway at 66 knots over ground, impacts the localizer antenna and comes to a stop 200 meters past the end of the runway. The crew declared Mayday and initiated the evacuation of the aircraft.

The aircraft received substantial including structural damage, both engines needed to be replaced. The localizer was damaged.

According to the operational manual by the operator the aircraft required a landing distance of 2,362 meters with flaps at 30 degrees and contaminated runway and 2,156 meters for a wet runway with 4 knots of tailwind (40 meters increase by each knot of tailwind). At flaps 45 the required distance would have reduced to 1,890 meters, however, flaps at 30 were preferred by the operator for passenger comfort.

The landing distance available (LDA) for runway 25 is 2,230 meters, while runway 07 offers a LDA of 2,403 meters. The runway was scheduled to be grooved, the work had not been conducted however at the time of the accident.

The BEA reported tower dispatched a ground staff to have the runway condition checked to determine whether the runway was wet, wet with puddles of water etc. The vehicle however had no tools or methods to determine the depth and extent of the puddles. The aerodrome operator was not aware of a Symposium held by the DGAC introducing and establishing guidelines to assess and communicate a runway condition.

The crew stated it was known that runway 25 was in poor condition with frequent presence of puddles after precipitation. They encountered moderate rain and puddles on the runway causing a temporary loss of control about one third down the runway.

There are different descriptions recommended by ICAO Annex 6 (wet, infected) and Annex 14 (wet, wet, puddles and flooded) while EU-Operations only know wet, wet and contaminated. The AOM referred to categorization of Annex 6. The term "wet with puddles" is not a recognized standard in Europe, standard phraseology may have alerted the crew to review the criteria (landing distance) for landing.

The BEA analysed that the crew was on their fifth sector of the day and had already expressed tiredness. During the descent towards Lorient a brief approach briefing was conducted, the landing distances were not recalled however. Although the controller informed and urged about the weather conditions present at the aerodrome, the crew did not react and conduct an additional approach briefing which likely would have resulted in review of landing distances in view of the runway conditions reported. Any possible thought process is being interrupted by the cabin crew informing the flight crew "cabin ready" at the same time. In addition, when the crew was about to run the "approach" checklist the controller interrupted (and ended) the checklist reading with one of his transmissions prompting the crew to put the checklist away.

The aircraft was stable while descending through 1000 feet, but accelerated to more than 10 knots above Vapp below 1000 feet and became unstable which would have required a go-around, however, there were no guidelines by the operator in case the aircraft destabilized later in the approach.

The crew did not query when the controller used non-standard phraseology to describe the runway condition in addition to incomplete assessment of the consequences of their decisions regarding landing configuration.

According to the threat and error management the crew verified the required landing distance and the landing distance available and found they had a margin of 80 meters. This however did not prompt the crew to review the threats when the runway condition and weather conditions deteriorated below what had been assesssed during the initial briefings. As a result the threat of an overrun was not identified.

Prior to the accident the lack of water retention had been identified on two occasions leading to the introduction of a project to groove the runway, the project was still being developed at the time of the accident and had not yet been implemented.

Standing water on the runway (Graphics: BEA):

Track of aircraft (Graphics: BEA):

http://avherald.com/h?article=4579315d/0000
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