A helicopter found the wreckage, on the Killen farm about 3km northwest of the aerodrome, about two hours later. Police handed the scene over to the Civil Aviation Authority on Friday afternoon.
An expert from the police Serious Crash Unit starting mapping the scene about 4.30pm on Friday and was expected to continue all day Saturday and into Sunday.
Wreckage was strewn over a distance of about 200m.
Kaikohe Gliding Club secretary Keith Falla, of Omanaia, described the pilot as "friendly, outgoing and a very valued member of the club".
Although in his 70s Mr Legler was "young at heart".
Mr Legler , who had been flying since his youth and had been a club member for at least 20 years, was the last to take off on Thursday in his own self-launching, electric-powered glider.
Mr Falla said he had no idea what had caused the crash.