Creebec DH8A at Rouyn on Jan 23rd 2019, runway excursion during takeoff

Last Update: March 9, 2020 / 17:03:06 GMT/Zulu time

Bookmark this article
Incident Facts

Date of incident
Jan 23, 2019

Classification
Accident

Flight number
YN-926

Departure
Rouyn, Canada

Destination
Montreal, Canada

Aircraft Registration
C-GTCO

ICAO Type Designator
DH8A

Airport ICAO Code
CYUY

An Air Creebec de Havilland Dash 8-100, registration C-GTCO performing flight YN-926 from Rouyn,QC to Montreal,QC (Canada) with 6 passengers and 3 crew, was accelerating for takeoff from Rouyn's runway 26 at 21:34L (02:34Z Jan 24th) when the aircraft struck a wall of snow with its left main gear and veered off the runway to the left coming to a stop in snow south of the runway. The aircraft was evacuated.

The Canadian TSB reported one person received minor injuries. The aircraft was towed back to the apron, the damage to the aircraft is currently being assessed.

On Mar 9th 2020 the TSB released their final report concluding the probable causes of the accident were:

- The pilot flying did not look far enough ahead for long enough to notice that the aircraft was deviating to the left before veering off the runway.

- Given that the pilot monitoring was not looking out the window to monitor the aircraft’s path, he did not notice the deviation and was therefore unable to help the pilot flying correct the deviation in the path during the take-off roll.

- The strong authority gradient between the pilots reduced the effectiveness of monitoring, which resulted in a failure to detect and correct the deviation from the departure path.

- During the takeoff-rejection procedure, the pilot flying accidentally caught the right engine power lever with his finger, pushing the lever completely forward, and placed only the left lever in the idle position, which produced a significant dissymmetry in the torque and accentuated the deviation from the path, resulting in the runway excursion.

- Since the pilot flying was able to place only 1 power lever in the idle position, it is highly likely that he did not have his right hand on the levers, contrary to what is stated in the standard operating procedures. Consequently, he was not ready to quickly and safely reject the takeoff.

Findings as to risk

- If pilots do not carry out a take-off briefing, they may not have a shared mental model of the actions that must be taken during the takeoff, increasing the risk of an accident.

- If the roles and responsibilities of the pilot flying and pilot monitoring are not well defined, monitoring may not be effective, increasing the risk that an aircraft’s deviation from its path may fail to be detected and corrected.

- If the accompanying pilot is not informed of the other pilot’s state of health before the flight, the accompanying pilot will be less prepared to take rapid and appropriate action as necessary, which could impact flight safety.

- If operators do not take into account the restrictions associated with pilots’ licences when assigning crew members to a flight, they risk pairing 2 pilots who both have a restriction associated with their licence requiring that they fly with an accompanying pilot, which eliminates the protection put in place by Transport Canada to reduce risks in the event of pilot incapacitation.

The captain (ATPL, 12,500 hours total, 8,000 hours on type) was pilot flying, the first officer (CPL, 1000 hours total, 300 hours on type) was pilot monitoring.

The TSB described the sequence of events:

At 2136:38, the aircraft reached the runway threshold and began its take-off roll without first coming to a stop. The aircraft was 17 feet to the left of the runway centreline, on a heading of 4° to the left of the runway centreline (Figure 1, position 1). Visibility was approximately 2 statute miles (SM) in snow showers. The crew could see the runway edge lights along the entire runway, but could not see the runway centreline markings, which were covered with snow.

Throughout the take-off roll, the aircraft maintained a heading of 4° to the left, but the crew did not notice that the aircraft was veering to the left, getting further and further away from the runway centreline.

At 2136:50, when the aircraft had reached a speed of approximately 80 knots, the PF realized that the aircraft was near the left edge of the runway. As soon as the aircraft reached 80 knots, 12 seconds after beginning its take-off roll, the left main landing gear rolled off the runway surface and hit the snow windrow 5 feet beyond the edge of the runway (Figure 1, position 2). The left wheel then lost speed rapidly and the aircraft spun approximately 5° to the left. The PF attempted to control the aircraft’s direction using the rudder pedals, and decided to reject the takeoff by reducing engine power.

At 2136:53, intending to grab both power levers with his right hand, the PF caught the right engine lever with his little finger, pushing it completely forward. At the same time, the PF only succeeded in grabbing the left engine lever and pulling it back completely. The asymmetric power made the aircraft veer even further to the left. The PF then tried to control the aircraft using the rudder pedals, but the nose wheel and right main landing gear also hit the snow windrow. The PF continued to try controlling the aircraft’s direction using the rudder pedals, but the aircraft continued to veer to the left. Approximately 5 seconds later, the aircraft hit a compact snowbank approximately 36 inches high about 40 feet beyond the edge of the runway, and spun rapidly to the left.

At 2137:01, the PF reduced power to the right engine.

At 2137:04, the aircraft came to a stop 3000 feet from the threshold and 200 feet to the left of the Runway 26 centreline, on a heading of 147° (Figure 1, position 3 and Figure 2). The PF then carried out the engine shutdown procedure.

The captain advised the FSS of the runway excursion and gave the order to evacuate the aircraft, but then changed his mind when he noticed that there was no danger and everyone could remain inside the passenger cabin while waiting for the emergency response crew. The emergency vehicles arrived, then the passengers were deplaned using the main door and taken to the terminal in the emergency vehicles.

One of the passengers received minor injuries. The aircraft sustained substantial damage to the fuselage, landing gear and propellers. The inspection of the aircraft after the accident revealed no faults before the impact that may have caused the aircraft to veer during the take-off roll.

The TSB analysed:

Given that Air Creebec serves many aerodromes where the runway has no centreline markings, the captain had enough experience to conduct a takeoff on such a runway. At night, with no visual references on either side of the runway, and with no runway markings visible on the snow-covered runway, the runway edge lights and the centre area at the point where the 2 rows of edge lights converge provide acceptable visual references for positioning the aircraft close to the centre of the runway on a heading close to the runway heading. It is possible for an aircraft to begin accelerating on takeoff while it is not exactly in the centre of the runway or exactly aligned on the runway heading. However, if the pilot looks far enough ahead for long enough during acceleration, the visual references produce a perceptible optical flow that enables the pilot to maintain the aircraft in the centre of the runway on the desired heading and to detect deviations from the centre of the runway.

In this occurrence, the pilot had positioned the aircraft 17 feet to the left of the runway centreline, on a heading of 4° to the left of the runway alignment. This heading was maintained without being corrected for approximately 12 seconds, until the left main landing gear hit the snow windrow.

Good spatial orientation begins with perception of external visual references to determine the current position, then anticipation of future positions by assimilating information pertaining to the speed, acceleration and direction of objects and surfaces in the observer’s field of vision. The runway edge lights and the centre area where the 2 rows of edge lights converged were sufficient to provide the crew with visual references that would help them to detect a deviation from the centre of the runway. However, the PF did not look far enough ahead for long enough to notice that the aircraft was deviating to the left before veering off the runway.

...

Although the PM does not handle the flight controls directly, he or she plays a crucial role in the execution of a takeoff. According to Air Creebec’s standard operating procedures (SOPs), the PM must check that the spoilers are retracted and the autofeather system is activated; once the aircraft has reached 80% torque, the PM must call “Through 80% torque” and set power to take-off power; once a speed of 70 knots has been reached, the PM must call “70 knots, power set”; finally, once the decision speed (V1 ) has been reached, the PM must call “V1, rotate”.37 Given that takeoff occurs quickly, the PM must direct his or her attention to the right place at the right time and spend enough time monitoring the flight’s progress and completing all of the tasks required for the take-off roll.

The evening of the accident, the PM completed all of his tasks and made all of the standard calls during the take-off roll. However, given that the PM was not looking out the window to monitor the aircraft’s path, he did not notice the deviation and was therefore unable to help the PF correct the deviation in the path during the take-off roll.

...

If the roles and responsibilities of the PF and PM are not well defined, monitoring may not be effective, increasing the risk that an aircraft’s deviation from its path may fail to be detected and corrected.

The lack of monitoring effectiveness between the crew members on the evening of the accident may be linked to a strong authority gradient between the PF and PM. On one hand, the PM did not believe that it was important to monitor the departure path since the PF was highly experienced. On the other hand, the PF felt obliged to closely monitor the actions taken by the PM, who was not very experienced, which diverted the PF’s attention longer toward what was happening inside the cockpit. The strong authority gradient between the pilots reduced the effectiveness of monitoring, which resulted in a failure to detect and correct the deviation from the departure path.

When the left main landing gear hit the snow windrow, the PF decided to reject the takeoff. However, during the takeoff-rejection procedure, the PF accidentally caught the right engine power lever with his finger, pushing the lever completely forward, and placed only the left lever in the idle position, which produced a significant dissymmetry in the torque and accentuated the deviation from the path, resulting in the runway excursion.

Since the PF was able to place only 1 power lever in the idle position, it is highly likely that he did not have his right hand on the levers, contrary to what is stated in SOPs. Consequently, he was not ready to quickly and safely reject the takeoff.

Metars:
CYUY 240400Z 01005KT 3SM -SN VV030 M10/M11 A2951 RMK SN8 /S02/ SLP019=
CYUY 240342Z 02006KT 3SM -SN VV030 M10/M11 A2951 RMK SN8 PRESFR SLP019=
CYUY 240300Z 03005KT 3/4SM -SN VV011 M10/M11 A2954 RMK SN8 SLP027=
CYUY 240254Z 03005KT 3/4SM -SN VV013 M10/M11 A2955 RMK SN8 SLP030=
CYUY 240247Z 02006KT 2SM -SN VV013 M10/M11 A2954 RMK SN8 SLP029=
CYUY 240203Z 03006KT 3SM -SN BKN038 OVC068 M10/M11 A2955 RMK SN3SC3AC2 SLP030=
CYUY 240200Z 03005KT 2 1/4SM -SN OVC038 M10/M11 A2955 RMK SN5SC3 /S01/ SLP031=
CYUY 240112Z 02006KT 2SM -SN VV020 M10/M11 A2958 RMK SN8 PRESRR SLP041=
CYUY 240100Z 03007KT 3SM -SN VV020 M10/M11 A2957 RMK SN8 SLP037=
CYUY 240012Z 04006KT 1 1/2SM -SN VV012 M09/M11 A2958 RMK SN8 SLP042=
CYUY 240000Z 04007KT 2SM -SN OVC020 M10/M11 A2959 RMK SN7SC1 SLP047=
CYUY 232300Z 06007KT 2 1/4SM -SN OVC016 M10/M11 A2960 RMK SN4SC4 PRESFR SLP050=
CYUY 232239Z 07006KT 2SM -SN OVC015 M10/M11 A2963 RMK SN4SC4 SLP058=
CYUY 232200Z 04005KT 1SM -SN OVC012 M10/M11 A2965 RMK SN5SC3 VIS VRB 3/4-11/4 /S03/ SLP067=
Aircraft Registration Data New!
Registration mark
C-GTCO
Country of Registration
Canada
Date of Registration
Pjpjpifqfhcpk Subscribe to unlock
Certification Basis
HnbhhbmhjfjhAdfqj Amjf gnqbnemiddgjpbkgggpebbn Subscribe to unlock
TCDS Ident. No.
Manufacturer
Dehavilland
Aircraft Model / Type
DHC-8-102
ICAO Aircraft Type
DH8A
Year of Manufacture
Serial Number
Aircraft Address / Mode S Code (HEX)
Maximum Take off Mass (MTOM) [kg]
Engine Count
Engine Type
Main Owner
Glqkjhcpciqpfcgepfbqlcclkcfdigbbedmljg lheblgqepqimlnq i bdflffj hnAjjdApnd Subscribe to unlock

Aircraft registration data reproduced and distributed with the permission of the Government of Canada.

Incident Facts

Date of incident
Jan 23, 2019

Classification
Accident

Flight number
YN-926

Departure
Rouyn, Canada

Destination
Montreal, Canada

Aircraft Registration
C-GTCO

ICAO Type Designator
DH8A

Airport ICAO Code
CYUY

This article is published under license from Avherald.com. © of text by Avherald.com.
Article source

You can read 4 more free articles without a subscription.

Subscribe now and continue reading without any limits!

Are you a subscriber?
Login
Subscribe

Read unlimited articles and receive our daily update briefing. Gain better insights into what is happening in commercial aviation safety.

Free newsletter

Want to know more and stay ahead? Get our free weekly newsletter and join 4933 existing subscribers.

By subscribing, you accept our terms and conditions and confirm that you've read our privacy policy.

Send tip

Support AeroInside by sending a small tip amount.

Related articles

Newest articles

Subscribe today

Are you researching aviation incidents? Get access to AeroInside Insights, unlimited read access and receive the daily newsletter.

Pick your plan and subscribe

Partner

Blockaviation logo

A new way to document and demonstrate airworthiness compliance and aircraft value. Find out more.

Virtual Speech logo

ELITE Simulation Solutions is a leading global provider of Flight Simulation Training Devices, IFR training software as well as flight controls and related services. Find out more.

Get updates

Never miss an article from AeroInside. Subscribe to our free weekly newsletter and join 4933 existing subscribers.

By subscribing, you accept our terms and conditions and that you've read our privacy policy.

AeroInside Blog
Popular aircraft
Airbus A320
Boeing 737-800
Boeing 737-800 MAX
Popular airlines
American Airlines
United
Delta
Air Canada
Lufthansa
British Airways