Both fires were doused and under control by 11.30am.
Fire officers Geoff Moore, Gary Anderson and Paul Doughty were at the front-line firing the high-pressure water at the flames. Intense heat forced them to retreat to rehydrate as station officer Jes Sorensen took over.
The heat was intensified by their protective clothing which one officer said was like "putting on a woollen blanket".
The Bronto aerial appliance with its ladder platform was used to fight the fire on the southern side.
In 30 minutes, 5000 litres from the 711 fire truck was used to fight the fire, while another 5000 litres was pumped to the site from a hydrant on Rogers St.
Senior station officer Bryce Coneybeer, still blackened from the fire site, said yesterday afternoon that the fire was spotted by Wanganui Aero Works pilot Dean Lithgow, who saw it develop very quickly.
Mr Lithgow was dumping lime on the treatment ponds near the airport and said when he turned around, he saw a big cloud of smoke billowing skyward.
"I was watching it ... it was very fast."
Mr Lithgow flew over and checked on the fire to see if lives were in danger. If necessary he would have filled his monsoon bucket to douse the fire before the fire appliances arrived.
"When I saw what it was and the fire appliances had responded, I left the area."
Mr Coneybeer said investigations were continuing into the cause of the first fire. The premises are about 200m apart.
Mr Coneybeer has warned the public to be extra vigilant around dry vegetation, as shown by the second fire.
