At least two engineers signed off on a one-tonne eagle that broke its wires and landed on the floor of Wellington Airport.
The airport has commissioned an independent engineer's report into the incident, which happened during Monday's 6.2 quake centred near Eketahuna in Tararua.
Airport spokesman Greg Thomas said the sculpture - which was "rigorously" engineered - should not have fallen down in the quake, which was far from the biggest it should have been able to withstand.
At least two engineers - from Weta Workshop, which built the eagle, and the airport - signed off on the eagle when it was installed. Thomas refused to name the engineers yesterday.
The sculpture, and another one like it, were unveiled with fanfare by Weta Workshop boss Sir Richard Taylor last month, just ahead of the second instalment in The Hobbit trilogy.
The eagles sat alongside a sculpture of Gollum, another character from Sir Peter Jackson's Hobbit movies.
At the opening it was said each bird - weighing a tonne each, with a wingspan of 15 metres - were held firmly in place by eight wire cables.
Taylor would not comment on the mishap yesterday, a spokeswoman for him said.
Thomas said it was too early to comment on whether the airport would seek compensation from Weta Workshop.
Closed circuit cameras failed to capture the eagle coming to the ground but witnesses had described it swinging before a connection snapped. The eagle "swivelled around", breaking "a number" of other cables before coming to the ground.
Each of the eight cables had a safety rating, meaning each could theoretically could carry a tonne.
The fallen sculpture was removed from the airport yesterday. But the other eagle remained up, with extra straps installed. The area beneath the Gollum character had been cordoned off as a safety precaution.
Because it was a temporary installation it did not need a building consent, Thomas said. After an independent investigation was complete it would be decided if the eagle would be rehung, and if the other one would be removed.
"They are much loved by tourists and locals. They are certainly something we would like to keep up but safety is always paramount."
WorkSafe NZ confirmed yesterday it was not investigating.
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