Mid 70s Bing Bonzer slung in the rafters of the excellent ZJ Boarding House in Santa Monica, photo Gary Crockett 2010
Its hard to know why the Bonzer never really caught on. Possibly its racy hydrodynamics, splayed channelling and tilted pectoral fins were just too plain spooky. According to Geoff Cater at surfresearch, the US brothers Duncan and Malcolm Campbell came up with the design in 1973. The delta shaped concave echoed Rogallo hang gliders of the late 1940’s, used by NASA in the recovery of returning space capsules. While the early 70s saw several attempts at multi-finned boards, it wasn’t until 1980 that all the pieces fell into place and Simon Anderson’s thruster made history.
And further paraphrasing Geoff: By the early 1970’s, hang-gliding was a sport in rapid transition with a large amount of media exposure. In late 1973, the Campbell Brothers licensed the design to Bing Surfboards for commercial development. The design then became associated with Bing’s head shaper, Mike Eaton, who had played a significant role in the development of the Twin fin 1 in 1970. The Bing models were noted for the wedged Bonzer decal that was laminated on the side fins.
As a sign of the powerful influence of Australia in world surfing at this time, the name Bonzer (also Bonzar, Bonza) is an Australian expression for “excellent”.
Australian exponents of the design included … Peter Townend (Gordon and Smith Surfboards), Ian Cairns (Gordon and Smith Surfboards) who rode a Bonzer to first place in the 1973 Smirnoff Contest at Laniäkea, Hawaii and Terry Richardson (Skipp Surfboards). Preceded (contemporary?) by the Tri-fin of 1971, the design had some influence on Simon Anderson’s Thruster of 1981. Further adaptation in 1988, the Phazer – a Stinger/Thruster adaptation (3 similar fins with 2 small Bonzer D-Fins) initially credited to Rusty Priessendorfer for Rusty Surfboards (USA). Later identified as another original design by the Campbell Brothers.
this information (and heaps more) sourced from surfresearch
See John Wythe White :Surf Wars :The Bonzar, June 16, 1999
http://www.honoluluweekly.com/archives/coverstory%201999/6-16-99%20Boards/6-16-99%20Boards.html