A routine call back to the club was made a few minutes before the emergency locator beacon went off, aero club president Bruce Govenlock said. There was no indication anything was wrong.
"I understand it was routine ... that he was advising they were going to fly lower," he told the Herald. "It was not many minutes from the last radio transfer that we noticed the beacon ... It doesn't appear there was any chance for a distress call and the last radio transmission indicated there was nothing wrong."
After the emergency beacon went off, another club plane already in the air went to investigate.
The crash site was close to the small settlement of Maraekakaho and State Highway 50 but was not visible from the road and difficult to access.
Mr Govenlock said it had been a harrowing day for the small club and its members, especially the ones who heard the beacon go off and realised the plane with their friend on board had crashed.
"They acted professionally and did what they needed to do ... It would have been very hard as they all know the pilot," he told the Herald.
Club members visited the home of the local man after the crash.
The plane reportedly appeared to stall before it nosedived into the river.
Alison Arthur was tending to her horses on her farm in Crownthorpe near Hastings when she spotted the plane in the air.
"It did a little loop and turned towards Hastings, but the plane was making a really, I have to say, shuddering and horrible sound ...
"There was this 'pop, pop, pop' and then there was this big bang," Ms Arthur told One News.
Mr Govenlock said the aircraft was 30 years old and had been well maintained.
Civil Aviation Authority investigators would arrive at the scene this morning.
