Incident: Jazz CRJ9 near Los Angeles on Nov 29th 2021, temporary runway excursion on departure, fuel leak, engine shut down in flight

By Simon Hradecky, created Tuesday, Nov 30th 2021 08:44Z, last updated Friday, Jul 5th 2024 18:52Z

An Jazz Canadair CRJ-900 on behalf of Air Canada, registration C-GJZV performing flight AC-8767 from San Diego,CA (USA) to Vancouver,BC (Canada) with 69 passengers and 4 crew, was enroute at FL340 about 110nm northnorthwest of Los Angeles,CA (USA) when the crew reported a possible fuel leak at the #1 engine (CF34), shut the engine down and decided to divert to Los Angeles. The aircraft landed on runway 24L about 30 minutes later and came to a stop with two blown main tyres. The passengers disembarked onto the runway and were bussed to the terminal.

The FAA reported the aircraft diverted to Los Angeles due to a fuel and engine issue.

On Dec 8th 2021 the Canadian TSB reported the aircraft was departing San Diego's runway 27 on center line, during the takeoff roll the crew noticed the aircraft was left of the center line and corrected. Later enroute about 110nm NNW of Los Angeles the crew noticed a fuel imbalance, the crew worked the checklist and shut the right (?) hand engine down. The crew declared emergency and diverted to Los Angeles. During the roll out the crew noticed the aircraft was pulling to the left and stopped on the runway. Emergency services reported the #1 tyre was deflated and smoke was coming from the wheel, the fire fighters sprayed the left main gear for brakes overheat. The passengers disembarked onto the runway and were bussed to the terminal. Maintenance determined the fuel imbalance was caused by a fault of the Fuel Quantity Gauging Computer (FQGC). The left hand flap was punctured by impact with a runway edge light during takeoff from San Diego. The left hand flap was temporarily repaired, the FQGC as well as the #1 tyre were replaced. The aircraft was subsequently ferried to Calgary,AB (Canada) for further repairs. The TSB is still assessing whether or not to open an investigation.

On Jul 5th 2024 the TSB released their final report concluding the probable causes of the occurrence (the TSB did not reveal a classification as incident, serious incident or accident) were:

Findings as to causes and contributing factors

- The aircraft was operating at night and in fog, in an area where visibility was between � statute mile and � statute mile. As a result, there were few visible cues available to the flight crew to identify and verify the aircraft�s position on Runway 27 at San Diego International Airport.

- When taxiing to position on the runway, the captain taxied the aircraft off the taxiway centreline in order to increase the runway distance available for takeoff. As a result, he had to rely on other visual cues to determine the aircraft�s position on the runway.

- When the aircraft was turning left to establish the runway heading in preparation for takeoff, the limited and ambiguous visual cues that were available likely met the captain�s expectations. As a result, he perceived the left runway edge as the runway centreline and aligned the aircraft laterally with the left edge of the runway, rather than its centre.

- The complexity of instrument flight rules operations on a single runway surface, with arrivals on one end and departures from the other end, created an environment where the flight crew perceived a time pressure for the takeoff. As a result, the first officer was completing the line-up checks while the captain taxied to position, and the first officer therefore did not monitor the progress of the taxi.

- Due to the reduced visual cues and perceived time pressure felt by the first officer, he did not recognize that the aircraft�s nose was aligned with the left edge of the runway when he assumed the role of pilot flying shortly before the take-off roll commenced.

- During the take-off roll, the aircraft�s left main landing gear wheels contacted and severed 3 runway edge lights, causing damage to the aircraft�s tires and flaps.

- The aircraft�s contact with the runway edge lights was not recognized by the flight crew because they perceived the sounds and vibrations to be normal contact with the embedded runway centreline lights and consequently continued with the departure.

- During the completion of either the before-takeoff or after-takeoff checklists, it is likely that the flight crew inadvertently pressed the gravity crossflow push-button switch instead of the co-located crossflow auto override push-button switch. As a result, during the flight, fuel periodically transferred between the aircraft�s wing tanks by gravity when the aircraft was banked left or right, leading to a worsening fuel imbalance condition.

- While operating at night with the autopilot on, the aircraft was placed in a sideslip toward the wing tank with the greater quantity of fuel, and this opposite bank was not recognized by the flight crew. As a result, the lateral fuel imbalance was not controlled, and continued to increase.

- The fuel imbalance, which was unrelated to the damage sustained during the take-off roll, led the flight crew to declare an emergency and divert to a nearby airport for an emergency landing.

- The checklists did not require the flight crew to close the gravity crossflow valve following the attempted Gravity Crossfeed Procedure. As a result, the open valve occasionally made the fuel imbalance worse during the subsequent manoeuvring and was at one point more than 3 times the maximum permissible.

Findings as to risk

- If flight crews line up on runways in the area before the displaced threshold or conduct intersection departures under degraded visual conditions or at night and without confirming the aircraft's lateral position on the runway, there is an increased risk of runway misalignments or runway side excursions.

- If foreign object debris on runways is not detected and identified in a timely manner, there is a risk that it will result in aircraft damage during critical phases of flight.

- When the wording in a checklist is ambiguous or unclear, or when the wording in an operator�s checklist differs from that in the checklist provided by the manufacturer, a flight crew may, in an effort to correct an abnormal or emergency condition, conduct procedures in ways not intended by the manufacturer, increasing the risk of entering into an undesired aircraft state.

The TSB analysed with respect to the captain's perceiption:

While the approach lighting for Runway 27 was not on at the time of the misaligned takeoff, the runway edge lighting and runway centreline lighting were active. As the captain brought the aircraft to a stop on the left runway edge marking, directly ahead was the runway edge lighting, and the first light in front of the aircraft was embedded in the runway surface in the same fashion as the approach lights around the centreline.

Per the standards, the edge lighting in the area before the displaced threshold is red when observed by flight crews aligned with Runway 27 either on the ground or in the air. When an aircraft is lined up to take off from the displaced threshold area on Runway 27, the runway centreline lights immediately ahead of the aircraft are seen as white. During the occurrence misalignment, although the captain would have seen red lights straight ahead and it would not have made sense for the runway centreline lights to be red in this area, it is possible that the visual presentation of the runway as a whole was close enough to the captain�s expected visual environment. It is also possible that in the context in which they were seen, the red lights that the captain saw ahead of the aircraft were interpreted simply as lights, without taking the colour into account.

The size of the runway shoulder to the left of the runway edge lights ahead of the aircraft, combined with the captain�s visual environment ahead on the left side of the runway�s edge lights, likely matched the captain�s expectation of the left half of the runway, to the left of the centreline lights. Given the darkness, the absence of lighting from the Runway 27 embedded approach light installation, and the degraded visual conditions, the captain�s focus was generally on the area close to and directly ahead of the aircraft, rather than on a longer range. In the daytime and in non-degraded visual conditions, other non-salient peripheral cues are normally available in the area. However, given the visual conditions at the time of the occurrence, these cues were not available to the captain.

And with respect to the first officer's perceiption:

Immediately before the takeoff of the occurrence flight, 9 aircraft arrived consecutively on Runway 09 in very short succession, with the last aircraft in the sequence conducting a missed approach because the flight crew was unable to acquire the required visual reference to land. At this time, the occurrence aircraft was 2nd in a line of 4 aircraft waiting to depart from the same runway in the opposite direction (Runway 27) before the next sequence of consecutive arrivals on Runway 09. KSAN being a single-runway commercial service airport, and one of the busiest in the world, the volume of arrivals and departures produces a fast cadence in the movement of aircraft. On the day of the occurrence, the fast cadence combined with the deteriorating weather likely resulted in a time pressure being perceived by the first officer.

When the air traffic controller instructed the flight crew of the occurrence aircraft to line up and wait, the first officer read back the instruction. He then proceeded with the before-takeoff checks followed by confirmation with the checklist and did the same for the line-up checks and checklist. When the aircraft entered the runway, the first officer, as a result of his cockpit duties, was likely switching his attention between the primary task of the cockpit checks and the task of performing monitoring and crosschecking. In this unfolding situation combined with the perceived time pressure, it was likely that the environmental cues in the runway environment were not salient enough for the first officer to detect the runway misalignment.

...

Given the first officer�s familiarity with both KSAN and flying with the occurrence captain, there was an added expectation that the aircraft was lined up on the centreline when the captain confirmed the runway alignment and transferred control of the aircraft to him. The degraded visual conditions at night and the short amount of time spent monitoring the visual environment resulted in the available visual cues not being salient enough to alter the first officer�s expectation that the aircraft was aligned with the centre of the runway.

With respect to foreign object debris on the runway:

At KSAN, the ATC tower�s airport surface detection equipment � model X (ASDE-X) provides increased cues to controllers, allowing them to more accurately identify all aircraft and vehicles on the airport movement area. However, the system is not designed to alert controllers to the hazardous situations leading to misaligned takeoffs. Therefore, during nighttime operations in degraded visual conditions, with no alerts to a potential runway misalignment, it is unlikely that the tower controller had sufficient cues to identify the occurrence aircraft�s misalignment on the runway.

In this occurrence, damage to the aircraft was minor. It required the replacement of the left main landing gear wheels and patching to repair the puncture holes in the left inboard flap. While the flight crew were unaware of the damage to their aircraft, the airport operator and controllers were also unaware of the damage to the runway lighting and the debris that remained on the runway because KSAN does not have a foreign object debris detection system. During the nearly 8 hours between the misaligned takeoff of the occurrence aircraft and the time at which the San Diego County Regional Airport Authority became aware of the event, debris left by the broken lights remained in the runway environment, posing a hazard for other aircraft taking off.

And the TSB analysed with respect to the fuel imbalance:

Shortly before the aircraft entered the departure runway, the first officer completed the before-takeoff checks, which required him to press the XFLOW AUTO OVERRIDE push-button switch to select �MAN� (manual position). This push-button switch is located on the overhead panel directly below the GRAVITY XFLOW push-button switch (Figure 15, Section 1.17.5.2.1 Normal procedures). Expanded procedures in the operator�s AOM require that once this push-button switch is pressed, the first officer should then verify that the MAN XFLOW message is displayed on the engine indication and crew alerting system (EICAS) and that there is no GRAV XFLOW OPEN message displayed. The after-takeoff checklist, which is normally completed after setting climb thrust when workload permits, requires the flight crew to press the XFLOW AUTO OVERRIDE push-button switch again to return it to the AUTO position.

The Regional Jet Series 700 and 900 aircraft previously had a known issue where selection of the crossflow pump to manual would trigger a spurious �XFLOW PUMP� caution message if the selection to manual were made while the automatic transfer is about to stop. The spurious caution message issue was addressed by the manufacturer of the fuel quantity gauging computer (FQGC) in 2006 by incorporating a software update. This update had been incorporated into the occurrence aircraft�s FQGC. However, more recent information from the FQGC manufacturer indicates that the spurious messages continue to occur. The source of the repetitive issue could not be determined due to limited data.

On the occurrence flight, the XFLOW PUMP caution was recorded at approximately 6500 feet in the initial climb, very close to the time the pilot monitoring (PM) (the captain) was completing the after-takeoff checks, which involved pressing the XFLOW AUTO OVERRIDE push-button switch. If this switch had inadvertently been left on AUTO for takeoff, this action would have set the push-button switch to MAN (manual), instead of returning the selection to AUTO.

The close timing of the XFLOW AUTO OVERRIDE push-button switch selection, possibly to manual, and the appearance of the caution message are consistent with the conditions that were previously known to occasionally result in a spurious warning. Therefore, because there was no post-occurrence indication of a pump failure, it is likely the �XFLOW PUMP� caution message the flight crew received was spurious, rather than a genuine indication of a pump failure, even though the aircraft�s FQGC had been updated with software designed to address this spurious issue.

As the aircraft continued to climb, recorded data indicates that it maintained a very slight bank angle to the left of approximately 1�. The crew was likely unaware of this bank angle because the angle was so slight and was similar to the static bank angle the aircraft experienced on the ground before takeoff. During this period of steady bank, the quantity of fuel in the left-wing tank remained steady or slowly increased, whereas the quantity of fuel in the centre and right-wing tanks continued to decrease.

As the flight continued, the flight crew monitored the fuel imbalance as instructed in the XFLOW PUMP checklist. Approximately 17 minutes after the �XFLOW PUMP� caution message, while the aircraft was climbing through flight level (FL) 310, the net fuel transfer from the right-wing to left-wing tank was greater than 5000 pounds per hour (lb/h). This rate of transfer is only possible with the gravity crossflow open given that it significantly exceeds the capability of the crossflow pump. This high rate of transfer preceded the �FUEL IMBALANCE� caution message by approximately 8 minutes, and the flight crew�s subsequent completion of the Gravity Crossfeed Procedure. While this recorded rate of transfer indicates that the gravity crossflow valve was open, the crew had not yet conducted any procedure that called for this valve to be opened.

The gravity crossflow valve is a completely manual selection and is not controlled by the aircraft�s FQGC. For the valve to be open at that time, it either had failed or had been inadvertently selected open by the flight crew. The push-button switch selections on the fuel control panel are not recorded on the aircraft�s flight data recorder, so it could not be determined with certainty that the flight crew opened the gravity crossflow; however, no mechanical faults were found with the valve, and the issue has not since reoccurred. The EICAS will display a message if the gravity crossflow shut-off valve fails, but there was no report of the message being displayed in this occurrence.

Furthermore, the gravity crossflow push-button switch is located directly above the XFLOW AUTO OVERRIDE switch on the overhead fuel control panel. The switches are in close proximity to one another and the recorded transfer rates indicate that the gravity crossflow must have been open. Therefore, the most likely scenario is that the valve was opened inadvertently by the flight crew pressing the push-button switch at some point before the high transfer rates occurred. The only 2 normal procedures that require the flight crew to press any push-button switch on the overhead fuel panel is when the XFLOW AUTO OVERRIDE switch is selected during the before-takeoff and after-takeoff checklists. It is, therefore, possible that the mis-selection occurred at either of these times.

https://flightaware.com/live/flight/JZA767/history/20211130/0100Z/KSAN/CYVR

Metars San Diego:
KSAN 300448Z 00000KT 1/8SM R09/0800V1000FT FG VV001 13/13 A3006 RMK AO2=
KSAN 300409Z 00000KT 1/4SM R09/1200V2200FT FG VV002 14/14 A3006 RMK AO2 T01390139=
KSAN 300351Z 00000KT 1/4SM R09/1600V5000FT FG VV002 14/14 A3005 RMK AO2 SLP176 T01390139=
KSAN 300304Z 34003KT 1/4SM R09/2000V3000FT FG VV002 14/14 A3005 RMK AO2 T01390139=
KSAN 300256Z 32005KT 1/2SM R09/1400V2600FT FG BKN001 14/14 A3005 RMK AO2 VIS E-SE 3/4 S-NW 1/4 T01440144=
KSAN 300251Z 33004KT 1SM R09/1600V2200FT BR SCT002 14/14 A3005 RMK AO2 SLP173 VIS SE 2 S-W 1/2 SCT V BKN T01440144 53007=
KSAN 300246Z 32004KT 1SM R09/1400V2000FT BR SCT002 14/14 A3004 RMK AO2 VIS SE 2 S-W 1/2 SCT V BKN=
KSAN 300235Z 30004KT 1/2SM R09/1200V2000FT FG BKN002 14/14 A3004 RMK AO2 VIS NE-E 2 S-W 1/4 T01440144=
KSAN 300156Z 00000KT 4SM BR SCT002 16/15 A3003 RMK AO2 VIS S-W 1 T01560150=
KSAN 300151Z 00000KT 3SM BR BKN002 16/15 A3003 RMK AO2 SLP167 VIS S 1 SW-W 3/4 NW 1 BKN V SCT T01560150=
KSAN 300149Z 00000KT 3SM BR BKN002 16/15 A3003 RMK AO2 VIS NE-SE 4 S 1 SW-W 3/4 NW 1 BKN V SCT=
KSAN 300141Z 00000KT 2SM BR SCT002 16/15 A3003 RMK AO2 VIS NE-SE 5 SW 1/2 W-NW 1 SCT V BKN T01560150=
KSAN 300051Z 31004KT 10SM FEW002 17/14 A3003 RMK AO2 SLP167 T01670144=
KSAN 292351Z 30004KT 10SM FEW005 19/13 A3002 RMK AO2 SLP164 T01940133 10233 20194 56008=
KSAN 292251Z 29006KT 10SM FEW005 19/14 A3002 RMK AO2 SLP167 T01940144=