The aircraft depicted is his old mount Pilatus Porter XW-PCI in landing mode whilst being operated by CASi in Laos in the 1970's.
More of Keith's art work can be viewed on :-
You may ask : what has this to do with NZ civil aircraft.
Well this aircraft is none other than Andrew Wallace's ZK-PCI - as depicted in this blogs header photo.
ZK-PCI is currently lurking somewhere in the UK.