What is Reduced Visibility Operations (RVOP) during heavy snowfall?

Summary: Operational impacts of Environment Canada forecast over the weekend

We’re a winter airport, but sometimes Mother Nature throws us a curve ball and it can affect our operations. As you may have seen Environment Canada’s snowfall warning on Saturday evening, we experienced challenges airside despite being fully staffed and ready to keep up to snow clearing standards and airline deicing demand. Deicing operations were halted due to heavy and wet snowfall in the last departure bank of the day.

The unexpected change in the Environment Canada forecast was our biggest issue. Calgary was not originally slated for snow; which changed quickly and drastically as winds changed from the East.  We faced extreme conditions with wind and whiteout weather that lead to calling reduced visibility operations. To put it into perspective, if you looked outside your window from 9:30 p.m. to 1 a.m. on Saturday or tried driving anywhere, you would have seen snow blowing sideways.

In reduced visibility operations:

• Aircraft take longer to get to the runway before they depart
• NAV Canada confirms and monitors all airside vehicle movements
• Airport Duty Managers send out an x-matters notification to airlines, airside contacts and in-terminal support

Not only is driving problematic, depending on the temperature, deicing has its challenges. Prior to departures, pilots check charts and collaborate with the tower to determine what kind of deicing solution will take place. Type 1 deicing fluid, an orange and hot solution, remove ices and snow. Type 4 a green anti-icing fluid keeps the ice at bay until after departure. Type 4 is unique as it has a hold over time (the time it takes to get to the runway) in minutes for aircraft to take-off before the anti-icing fluid becomes ineffective.

On Saturday, the weather conditions meant a zero-minute hold over time. With that, we had to call a halt to deicing operations as no aircraft was able to deice properly before take-off. At 1:30 a.m. Sunday, the weather conditions improved and deicing resumed allowing aircraft to depart safely.