John Harris 
Mercenaries [PDF ebook] 

Ira Penaluna, First World War pilot, sees his airline go bankrupt in Africa and grabs at the chance to instruct pilots in China. But Ira hasn’t reckoned on the beat-up, burnt-out wrecks he is expected to teach his students in, or on the fact that his pupils speak no English. Though aided and abetted by an enthusiastic assistant, an irresponsible Fagan and his brooding American girlfriend Ellie, Ira finds himself playing a deadly game, becoming embroiled in China’s civil war. The four are forced to flee but the only way out is in a struggling pile of junk flown precariously towards safety. Will they make it?