ASN Wikibase Occurrence # 221608
This information is added by users of ASN. Neither ASN nor the Flight Safety Foundation are responsible for the completeness or correctness of this information.
If you feel this information is incomplete or incorrect, you can submit corrected information.
| Date: | Monday 28 January 2019 |
| Time: | 18:48 UTC |
| Type: |  Embraer ERJ-175SU (ERJ-170-200 SU) |
| Owner/operator: | Air Canada Express, opb Sky Regional Airlines |
| Registration: | C-FEJB |
| MSN: | 17000086 |
| Year of manufacture: | 2005 |
| Fatalities: | Fatalities: 0 / Occupants: |
| Aircraft damage: | None |
| Category: | Serious incident |
| Location: | Toronto–Lester B. Pearson International Airport, Ontario (YYZ) -
 Canada
|
| Phase: | Take off |
| Nature: | Passenger - Scheduled |
| Departure airport: | Toronto-Pearson International Airport, ON (YYZ/CYYZ) |
| Dallas/Fort Worth International Airport, TX (DFW/KDFW) | |
| Investigating agency: | TSB |
| Confidence Rating: |  Information verified through data from accident investigation authorities |
A group of snow removal vehicles, consisting of three combination sweeper/snow plow vehicles and one snow blower vehicle, had begun clearing snow from the taxiways at Toronto/Lester B. Pearson International Airport (CYYZ), Canada.
Forward visibility was reduced due to the snowy conditions, and the snow removal equipment created more blowing snow. As a result, the drivers' forward visibility was reduced to near zero. In addition, snow had accumulated on the manoeuvring area, obscuring some of the visual cues such as paint markings on the surface of the taxiways, inset taxiway centreline lights, and holding position lights.
Due to the reduced visibility, the ground controller could not see all of the traffic on the airfield from the control tower but, as is common practice, was using the ground radar to identify aircraft and vehicles and to control traffic on the airport’s manoeuvring areas.
The vehicles were operating as a group. The lead plow vehicle’s call sign was PLOW 862, which was used during communication between the lead plow vehicle and the ground controller. However, the radar screen showed the call sign for this vehicle as PLOW 170.
Although all of the vehicles were equipped with very high frequency (VHF) radios capable of communicating with the ground controller, PLOW 862 was performing the radio work, and the ground controller was referring to the group as "PLOW 862 and company."
The operators of the other vehicles in the convoy were listening to the VHF radio on the ground frequency, and following PLOW 862, which is a common procedure for a group of vehicles operating together at CYYZ.
At 13:4716, PLOW 862 and company were proceeding south on Taxiway E and were instructed to turn left onto Taxiway C (eastbound and parallel to Runway 06L), and to continue snow removal operations. As the vehicles reached the intersection of taxiways E and C, they made a wide left turn to position some of the snow near the south edge of Taxiway C, and inadvertently lined up with the entrance to Taxiway C2.
Next, PLOW 862 inadvertently proceeded onto Taxiway C2 instead of Taxiway C and continued toward Runway 06L, with the other vehicles following. At this point the operator of PLOW 862 believed that they were on Taxiway C.
As the lead plow operator approached and then crossed the Runway 06L holding position, he did not see any of the associated lights or visual cues. In addition, the drivers of the 3 vehicles driving in the group behind the lead plow did not see any of the visual cues. The 2 vehicles behind the lead vehicle also crossed the holding position, and the 3rd stopped behind the vehicle ahead, before the holding position.
At 13:47:45, when Sky Regional flight SKV7665 was cleared for takeoff from Runway 06L, the runway visual range was 3000 feet. With visibility reduced to this level, the flight crew could not see Taxiway C2 from their position at the threshold. A few seconds later, the flight crew began their take-off roll.
At 13:48:21 the stop-bar overrun alarm in the control tower activated. The ground controller observed the vehicles crossing the holding position on the ground radar and instructed the lead plow to stop by transmitting the instruction "PLOW 170 hold your position." The driver of PLOW 862 (the lead plow) did not recognize that this instruction was intended for him. When the vehicles did not stop, the ground controller repeated the instruction, this time transmitting "PLOW 170 STOP."
The vehicles continued, and the ground controller transmitted "PLOW 862 STOP." With no immediate response, the ground controller then repeated the instruction. The lead plow came to a stop at 13:48:31. The ground controller then told the lead plow operator "you are on the runway, hold position there."
When PLOW 862 came to a stop, it was approximately 270 feet beyond the holding position for Runway 06L, but still on the taxiway surface, approximately 100 feet laterally from the edge of the runway.
At about the same time that the plow vehicles were crossing the holding position (13:48:26), the south tower controller instructed flight SKV7665 to abort its takeoff, using the phraseology "Maple 7665 abort."
Due to the snowy conditions, the flight crew could not see the plow vehicles ahead; however, the flight crew heard the abort call and immediately began the abort sequence in accordance with company procedures, using heavy brakes and thrust reversers. At this point, the aircraft was in the high-speed regime of the takeoff: the airspeed was 110 knots.
The aircraft came to a stop on the runway centreline, approximately 200 feet before the intersection of Runway 06L and Taxiway C2, and separated from PLOW 862 by about 200 feet laterally.
Findings as to causes and contributing factors:
- The transponder installed on PLOW 862 was not updated to remove the code from the vehicle on which it had previously been installed. As a result, the incorrect code was shown on the ground controller’s display.
- NAV CANADA did not have procedures in place to track or report vehicle transponder errors to the Greater Toronto Airports Authority.
- Due to the reduced visibility from blowing snow, the operator of PLOW 862 was not aware that the vehicle was on Taxiway C2 as it approached the holding position. As a result, the operator was not looking for, nor expecting to see, any of the visual cues that would have alerted him that the vehicle was approaching an active runway.
- Because some of the visual cues at the holding position were obscured by snow, and others may not have been working, the cues were not conspicuous enough to alert the operator of PLOW 862 to the vehicle’s proximity to the runway. As a result, PLOW 862 and the following 2 vehicles incurred on the protected area of the runway.
- The ground controller recognized the incursion by PLOW 862 and instructed the vehicle to stop 4 times; however, the first 2 instructions were addressed to PLOW 170 rather than PLOW 862. Immediately after the ground controller used the correct call sign, PLOW 862 came to a stop 10 seconds and 270 feet after crossing the holding position on Taxiway C2.
Accident investigation:
 |
|
Sources:
TSB
Images:
The intended and actual route of the plow vehicles, and the locations of PLOW 862 and flight SKV7665 when they came to a stop (Source: Google Earth, with TSB annotations)
Revision history:
| Date/time | Contributor | Updates |
|---|---|---|
| 06-Feb-2019 19:33 | harro | Added |
| 06-Feb-2019 19:43 | harro | Updated [Location, Narrative, Photo] |
| 21-May-2020 16:22 | harro | Updated [Narrative, Photo, Accident report, ] |
Corrections or additions? ... Edit this accident description
The Aviation Safety Network is an exclusive service provided by:
Quick Links:
| ASN Home | Send Correction / Feedback |
| FSF Home | Disclaimer | Copyright |
| Contact Us | Privacy Policy |
| Press / Media |
CONNECT WITH US:
©2024 Flight Safety Foundation