A direct hit on the pod containing observation decks and restaurants at the Sky Tower by a light aircraft would be life-threatening but would not topple the 328m tower, according to Gordon Moller, the architect who designed the skyscraper 12 years ago.
He said if a small aircraft flew intothe lower reinforced concrete shaft it would cause nothing more than surface damage. If it flew into the pod with five or six levels of observation decks and restaurants it would cause damage to the aluminium cladding and windows and, possibly, a fire.
The windows were made of sophisticated laminated, double-glazed thick glass but would break from the impact of a plane flying into them at 200km/h, he said.
Mr Moller said the tower was primarily designed from a safety perspective for threats such as fire, wind and earthquake. It was hard to design for a "severe impact", he said.
The tower had protected refuges in the lower part of the pod in the event of a fire, a fire-rated shaft and very good fire-fighting systems.
Sky City media relations manager Paul Gregory said a hit could have damaged communication facilities on the mast.
