The tallest fire trucks needed to battle Auckland's SkyCity blaze were out of service or partially broken when the fire started, a union boss says.
New Zealand Professional Firefighters Union vice president Joe Stanley claimed the fire could have been put out within two hours if at least two of the units had been immediately available.
The fire burned for nearly 30 hours, pumping tonnes of potentially toxic smoke into the air, wreaking havoc on the Auckland central business district and further damaging the unfinished $700 million New Zealand International Convention Centre.
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But Fire and Emergency New Zealand [FENZ] region manager Ron Devlin said extra heavy aerial appliances would not have changed the way the fire was initially fought.
"This is a complicated fire to fight. In this instance, the heavy aerial appliances arriving earlier, or additional heavy aerial appliances, would not have made any difference to the approach taken."
Stanley told the Herald the lack of heavy aerial appliances - which have 32 metre high turntable ladders - directly contributed to the fire becoming out of control and burning for nearly two days.
"It's absolutely our belief that the fire could have been put out within the first two hours if we could have responded two aerial appliances.
"We are not taking our aerial capability seriously enough. We are putting firefighters and public safety at risk and that's unacceptable.
"Continued under-resourcing of our aerial fleet will eventually lead to a significant injury or death of a firefighter or member of the public."
Auckland usually has two heavy aerial trucks, stationed at Parnell and Auckland City.
The one in Parnell was two days into a two-week service when the fire call came through at 1.13pm on Wednesday, the union said.
It said mechanics working on the oil change quickly recommissioned the truck but it was two hours before it got to the scene.
The other high-ladder truck, based at Auckland City, has been off the road for months because of concerns over its safety, the union said.
A third, relief heavy aerial appliance, usually stationed at Auckland City and shared between Hamilton and Auckland, was covering for Parnell yesterday.
In July, FENZ confirmed a rule removing all heavy aerial appliances from private fire alarm activations in the Auckland CBD.
But the union says what the rule actually did was remove heavy aerials from every call in the CBD including confirmed fires.
It meant yesterday's heavy aerial should not have been sent on the first alarm.
But the Herald understands a Northern Fire Communications Centre manager over-rode the procedure and initiated the response manually.
However by the time the 23-year-old truck got to the scene and set up, twice, 20 minutes had lapsed before it began spraying water.
NZPFU Auckland Local Branch aerial representative Adam Wright said because it was the only heavy aerial on sight it was set up twice to find the best vantage point.
"Up until they made cuts to our turn-out system we would normally send two heavy aerials to a building fire like that.
"The first one would set up and then if you're in the wrong place you can guide the second heavy aerial where to go.
"But because there was only one heavy aerial they set up, they weren't in the ideal location so they had to move and set up again, and then get water onto the fire."
At the third alarm Hamilton's aerial appliance, known as a snorkel with a 25m ladder, took almost two hours to arrive.
By then the fire was out of control despite the best efforts of firefighters to attack the blaze from neighbouring rooftops.
"Normally that would be the fourth arriving aerial into Auckland. But yesterday it was the second."
All of this meant that for the first two hours only 60 litres of water per second was being sprayed on to the fire by a heavy aerial appliance, instead of 200 litres.
While three small aerials from South Auckland attended the blaze, Wright said those trucks with 17m high ladders were better suited to fires in two-storey buildings.
"Our aerial fleet is completely depleted. They've introduced a procedure that removes all our aerials from all initial calls - even confirmed fires.
"And while there are adequate numbers of aerials there now, there was a huge time-delay and they are at their limit of their operating window on the Nelson St side of the building."
Devlin told the Herald a heavy aerial appliance was dispatched immediately when requested by the first arriving crew, who escalated the incident level.
"The heavy aerial appliance arrived to the scene within 10 minutes of being dispatched."
He confirmed one of the two heavy aerial trucks based in Auckland was undergoing routine maintenance but said it was "on scene in full operational condition by 3pm".
He said it was normal procedure for an aerial from outside Auckland to attend a fire of this scale.
"The aerial appliance from Hamilton arrived around 3pm and is currently still in attendance."
Devlin said while one of the appliances had a slightly damaged cable, all this meant was that it could only be operated from the top, which was normal practice.
"As with all major incidents, we will be reviewing our response and will take any learnings into consideration."
Stanley took exception to the implication the city was adequately resourced.
"I disagree absolutely and unequivocally with Ron. I think he's wrong. We're not in a good position when it comes to aerials," he said.
"Our aerial fleet is unserviceable or has faults in it. It is under maintained and we've under-resourced it for so long now it's ineffective for it's proper usage."