The family of the second pilot killed in a light plane crash in Sydney's south-west have described him as "fearless, brilliant and above all else, a generous and loving man with a heart of gold".

Khadervali Gagguturu, 60, was flying one of the light aircraft that collided midair at Belimbla Park on Saturday. 

He is one of three men who died in the crash.

In a statement to ABC News, his son Saleem said those who knew him are "devastated" by his death. 

"He went out of his way to help anyone and everyone," he said. 

"My mother, brother and I love him so much and his loss has left us, and all our family and friends, devastated and broken.

"Despite being a highly intelligent mechanic, programmer and pilot, his lifelong passion has been flying and he died doing what he loved. 

It was confirmed on Sunday that experienced Qantas pilot Gary Criddle was also a victim of the crash.

His family remembered him as a "very much-loved husband, father, grandfather and aviator".

"We're absolutely devastated beyond words and in total shock by this tragic loss," they said in a statement.

"Gary was an extremely experienced pilot with 36 years at Qantas and 20 years in the navy and air force.

"He was a mentor to many aspiring pilots and an avid adventurer with plans to sail the world," they said.

A third man, who died at the scene alongside Mr Criddle and Mr Gagguturu, has not been identified. 

Investigators from the Australian Transport Safety Bureau remained at the scene on Monday afternoon, collecting forensic evidence from the two crash sites in attempt to determine what went wrong.

One of the planes had been travelling from Cessnock to Wollongong, while the other was from an airfield at The Oaks.