40kg panel could have hit at 100km/h

The 40kg piece of cladding that peeled off an Auckland apartment building would have hit with the impact of a small car crushing someone against a wall, a physicist says.

The panel fell from the 13th floor of Victopia apartments on the corner of Victoria St West and Nelson St. A witness said she heard a “very loud bang” then saw dust fly up from behind a construction fence when the panel fell just after 1pm.

Several pedestrians on the footpath below visibly jumped at the impact before retreating to a covered pavement tunnel.

It appeared the cladding had not fallen straight down but had been caught by the wind and pushed several metres sideways as it fell.

University of Auckland physics lecturer Dr Geoff Wilmott, who made some rough calculations for the Herald, said assuming the panel measured 1m x 1m, and it fell edgeon, it could have reached speeds of around 100km/h by the time it hit the ground.

Anyone standing underneath would have sustained serious injuries even if it hit face-on — the best-case scenario — because that would spread the impact.

“The pressure would be about the same as for a small car (1000kg) running into a wall at about 20km/h,” he said.

“Not too bad for the car but you don’t want to be caught between it and the wall.”

If it had hit edge-on, it could have impacted at 10 times that pressure — like a small piece of a car hitting you at 200km/h, he said.

“If you had the choice, you’d want to be hit face-on. It’s definitely going to cause serious injury if it hits someone.”

Police closed a section of Victoria St because of debris and fears more panels could come down.

Inspector Cornell Kluessien said: “The wind and the rain is the concern because now that panel is missing more water will get behind it. Another panel may get loose and blow onto the road.”