"Our families are devastated to lose such wonderful men and experienced pilots; we would like to thank our family and friends, and especially the extended gliding fraternity for their support."
Mr Speight first learned to glide at the Taieri Plains near Dunedin in 1959. His contribution to New Zealand gliding both as a role model and aviator "will be greatly missed", the families said.
Mr Walker started out gliding in the early 1970s and was influential in the development of the Omarama Airfield.
He also flew for New Zealand at many international gliding events.
That led to the World Gliding Championships being held in Omarama in 1995, one of Mr Walker's "proudest moments", the family statement said.
The Queenstown community has also been left reeling following the deaths.
Gliding New Zealand president Karen Morgan, of Balclutha, summed up by saying, "The centre of our world has gone".
The two men were her "neighbours" at Omarama's glider hangar.
"I had Bill on one wing and Davey on our tail - so for me, personally, it's going to be an enormous loss of two of our closest friends."
She described Mr Speight as "the loveliest man", always cheerful and helping others.
Mr Walker was "a smiley, careful fella" and one of the greatest visionaries in gliding, she said.
The crash is being investigated by Namibian authorities.
-NZME. Otago Daily Times
