It's a CONFUSING world.
Thank goodness for Doctor Wiki:
"It was developed from the Bennett Airtruck designed in New Zealand by Luigi Pellarini. It has a 1 tonne capacity hopper and is able to ferry two passengers as a topdresser. Other versions can be used as cargo, ambulance or aerial survey aircraft, and carry one passenger in the top deck and four in the lower deck.
The Airtruk is also sometimes known as the Airtruck. Because the name "Airtruck" was registered by the New Zealand companies Bennett Aviation Ltd and Waitomo Aircraft Ltd, for their PL-11, Transavia