GREEN BAY - "My dad's just a good guy. He was a great dad," said Steve Rank.Those words from the son of a Green Bay man who drove into the East River Friday afternoon.Officials say 74-year-old George Rank lost control of his van and died because of a medical condition.Rank was the owner of Green Bay's iconic, downtown eatery - Al's Hamburger Shop. The restaurant opened in 1934.Police and fire officials responded to the accident near the intersection of Main and Roosevelt streets shortly before five o'clock.Saturday, Rank's family and friends shared their memories of the man they knew."I was lucky to have him," Steve Rank said.He says his dad worked at the family owned restaurant for more than 40 years."He was always laughing, a hard worker, but goofing around and joking," said customer Lisa Delvaux.Others say he always made them feel welcome."There's a family atmosphere, everybody's family that walks through the door," said customer Susan Moore.People we spoke with during the lunch rush agreed Rank was dedicated to the restaurant.Steve Rank tells FOX 11 his dad also gave back to the community.He says his father was looking forward to this day - the Saturday Farmers Market opening day at its new location.That's because he had an outdoor seating area built for his customers.But George Rank won't get a chance to see his customers enjoying the new benches and tables.Green Bay Metro Fire crews pulled Rank from his van after it went down an embankment and into the East River Friday afternoon.Fire officials estimate he was underwater for around 15 minutes before rescue workers freed him.Steve Rank thinks his dad accidentally hit the wrong pedal while parking his van at Karen's Pub."We think his foot was swollen and that he might have hit the brake and the gas pedal," Rank said.A photo of Rank and his wife hangs in a corner of the restaurant."He will be sadly missed by all of us and everybody that knew him," said Rank.Green Bay police are still investigating the accident.The Brown County Medical Examiner says George Rank did not drown and alcohol was not a factor.There are apartments above Karen's Pub, and the accident damaged the exit stairs displacing at least five people.