"He would not have wished to do anything to hurt his family and I know he would be devastated to be the cause of our pain.
"We are so proud of him, he was a credit to us and he loved his life - he was always doing lots of things."
Mrs Hill said her son was a keen rugby player and always had a lot of friends.
"When he moved to the base at Ohakea, I not only missed him - I missed his friends as well.
Mrs Hill said the family are grateful for the support of the RNZAF - Joshua's brother Stave is also an airman, who was training in Auckland when he heard of his sibling's death.
"They organised a flight to bring him home to be with his family and I am very glad he is here with me and his dad Hunter, brother Sam and Josh's partner Elise."
The family will hold a service at their home in Longbeach Drive on Friday.