A lecturer at the University of Canterbury for many years up until his retirement in 2002, he wrote several biographies of senior Royal Air Force officers, including Hugh Dowding and Keith Park.
[2][3] Orange authored numerous articles and conference papers in addition to several books, primarily biographies of senior officers of the Royal Air Force.
His subjects included Hugh Dowding and Keith Park, both of whom played prominent roles in the Battle of Britain as well as Johnny Checketts, a New Zealand flying ace.
[3] His last book, exploring the relationship between Prime Minister Winston Churchill and the senior command of the Royal Air Force, was released posthumously by the publishing company Grub Street.
It received praise for "offering a readable and at times insightful account of Britain’s leading airmen" but noted that its discussion of Bomber Command's air offensive "seems inadequate".