AN investigation into the cause of the ultralight aircraft crash that left Ballina pilot Ian Byrne critically injured is underway.
Recreational Aviation Australia CEO Michael Linke said he was unable to speculate about what may have caused the crash.
"We will continue to investigate over the course of the next few weeks and gather all the information we can to inform us as to the cause of the accident," Mr Linke said.
"This will include talking to eyewitnesses, gathering any information from the aircraft and aircraft reporting systems.
"That includes instrument panel readouts, log book entries and any additional information available to us from the aircraft history and usage."
Once the investigation is complete, the aviation body will put together a formal report together with the NSW Police Force Airwing PolAir and it will then be submitted to authorities with the findings.
Mr Linke said it would take about two to three weeks before preliminary findings were released.
He said incidents like this were "few and far between".
"In 12 months we average about seven incidents per 10,000 landings," he said.
"It's a very safe sport and our members are well trained."
The Drifter ultralight Mr Byrne was piloting crashed into a private property on Martins La, Knockrow about 9am on Monday.
Emergency services including the Westpac Life Saver Rescue Helicopter, police, ambulance, SES and RFS responded to the incident.
Mr Byrne was taken to the Gold Coast University Hospital in a critical but stable condition.
The hospital was unable to give an updated condition report.