NZFF

Fact is , Its called 'The Crawler', look carefully you can see 'National Airways Corporation' Logo on the rear, It was pointed out to me that under the red paint one can still see its military heritage, still showing and old NZ Army number, this bulldozer was used in the Pacific during WWII , it did get around , only a couple months back Air NZ gifted the unit to the Wigram Museum , putting a a Goblin engine into a Vampire one said how are we going to do this , one bright spark said what about 'The Crawler' , Sam told me it started like it was brand new and proved itself again 80 years later lifting the engine and putting it into the Vampire ! .

Huh, interesting looking machine.
What would NAC have used it for?

I would say look at the height off the crane rig and probably a very good guess used to sling all sorts off engines, onto DC-3 for a starter maybe the Bristol Freighter as years went by it sat in the back in one off the old maintenance sheds collecting dust , maybe its the rebuild of Christchurch Airport recent and the current changes someone was wise enough to gift it to Wigram.

I did say next time they have an open day they should bring it out just to see it operation . It is amazing checking out the tracks on it , simple flat plate steel and causes no damage at all to the tarmac or concrete.