An 87-year-old pedestrian was hit by a car in Whitley Road, Whitley Bay at 09:45 GMT, the GNAAS said.
There was no room to land the helicopter at the scene, so the crew flew to the town's nearby war memorial intending to reach the man on foot.
But the team flagged down a passing bin lorry, which took them to him.
The man was hit by a black Audi at the junction with Crawley Road, police said. The road was closed for about two hours.
The doctor and paramedic treated the man at the scene and took him by road ambulance to Newcastle's Royal Victoria Infirmary, where he is in a serious condition.
Jane Peacock, the GNAAS paramedic, said: "We just thought a bin man would know the roads.
"We jumped in the front and they took us straight there. They were brilliant; we can't thank them enough."
The mayor of North Tyneside Norma Redfearn said she was "immensely proud" of the bin men.
Police are appealing for witnesses.
A crew from the Great North Air Ambulance Service (GNAAS) flagged down a bin lorry to reach a critically injured patient in North Tyneside.