Thanks Nigel. The airshow was put on by The Vintage Aviator, who build and restore WW1 fighter planes. Some are accurate replicas, some are the genuine article. Likewise, some are NZ owned, some have international owners. The planes aren't all related to The Vintage Aviator, many have been restored/built elsewhere, but these guys are responsible for putting the show on.

They have an excellent website with lots of info: www.thevintageaviator.co.nz