The airshow, to celebrate the 75th anniversary of the Royal New Zealand Air Force, was expected to be a huge event. More than 10,000 people bought tickets online and another 50,000 were expected to turn up at the gates.
Those trapped in traffic had doubts they would even see the show as they crawled towards the air base at around two kilometres an hour.
Nic Steenhout, 40, said he left his home in Palmerston North at 9am. The journey would usually take 25 minutes but by 11am he was yet to reach halfway.
"We might not be there till after lunch at this rate. This is the military, you would expect them to be quite logistical and organised," Steenhout said.
"A whole lot of people are getting out and walking."
Steenhout was unable to see the planes flying from the road, he added.
Local resident Leslie Potroz said the traffic had built up from 8am - an hour before the show kicked off.
"It's terrible. It's been there all morning, since I went to get the mail. There must be a lot of disappointed people. A lot of people are turning around."
The motorcyclist involved in the accident near the air base was taken to Palmerston North Hospital with serious head injuries.
From Monday, ticket holders will be able to have their ticket price refunded through Eventfinder.