Slippery Surface Excursion Thread

[pelmet]

There is a runway excursion thread but that is mostly pilots coming in way to fast or high. I thought I would separate out ones under slippery conditions(and include taxiways and ramps)....

C-GWSA, a WestJet Airlines Boeing 737-800, was operating as flight WJA629 from Toronto/Lester
B. Pearson Airport (CYYZ), ON, to Calgary International Airport (CYYC), AB. After touchdown, the
aircraft's speed reduced to 60 knots; however, the flight crew were unable to exit as planned on
Taxiway D4. Due to windrows of snow, the flight crew continued the taxi to exit at the end of
Runway 35R. When the flight crew attempted to slow for the turn to exit the runway at Taxiway D,
braking action was poor and the aircraft overran the threshold by approximately 16 feet but
remained on the paved surface. The flight crew were able to turn around and taxi to the gate
without further issues. At the time of the landing the runway visual range (RVR) for Runway 35R was 2600 varying to
3000 feet with a report visibility of 1/4 statute mile in moderate snow. 20 minutes after the arrival of
WJA629, the Canadian runway friction index (CRFI) recorded for Runway 35R was 0.22 for section
A, 0.26 for section B, and 0.28 for section C. The GRF runway surface condition report was 2/2/3.
Following the flight, company maintenance inspected the aircraft and replaced 2 main wheels due
to tire wear. The aircraft was returned to service.


.....from TSB.