Early investigation shows ice that crashed through roof was from WestJet flight

The ice made it all the way to the basement floor.

“This is a most unfortunate incident for the family whose home was damaged and we will be reaching out to pay for all necessary repairs to their home,” Stewart said in the email.

John Lee with the Transportation Safety Board said he has contacted the homeowner where Friday’s incident happened, and instructed the homeowner to keep the ice in the freezer until it can be tested.

Lee said incidents of ice crashing through roofs from passing planes are rare. However, he said the home where it happened Friday is very near to another home that had the same thing happen a number of years ago.

Lee said the ice from that incident fell from a Boeing 737 and originated in a lavatory sink. Planes don’t discharge their toilet water during flight, Lee explained, but they do eject the water that’s used for handwashing.

In order to keep that water from freezing as chunks, part of the drainage system is heated. However, Lee said the heating element on the 737 failed and ice formed as a ball at the end.

As the plane descended and the air became warmer, the ball melted and broke away.

“This ice has to come off at the right time and also be on a path that it’s going to hit a house. So I think the stars have to line up pretty good for this stuff to happen,” Lee said, although he admitted it could happen more than we know about.

“We only know about these things if it hits someone’s house or it hits the street.”

Lee said there are cases where water from aircraft toilets leaks from valves, forms ice and breaks away. Such cases were once known as “blue ice” but Lee said he isn’t sure if planes still use blue water in their toilets anymore.

Sometimes, he said, investigations into falling ice have a simpler explanation.

Lee said one case in Alberta turned out to be ice that broke away from the top of a steep roof.

“It slid down the roof and hit some lawn furniture,” Lee said.

—by Rob Drinkwater in Edmonton

The Canadian Press

by Canadian Press

Early investigation shows ice that crashed through roof was from WestJet flight

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