Tree Frog - a 1960's spy story about unmanned aerial vehicles

I came was recently browsing through a list of books that the Readers Digest company had included in their condensed books series, and came across this one that looked interesting. Tree Frog was published in 1966, and is an easy to read thriller in the laconic style of Alastair MacLean or Desmond Bagley. The protagonist is similar in many of these books, being a slightly jaded hero who is thrown into a situation where his incomplete knowledge leaves him at the mercy of superiors who are orchestrating a web of deceit, espionage and treachery. The hero is no superman, and yet generally prevails in the end by cleverly figuring out what is really happening, and who the good and bad guys are. This genre of thriller can be imagined as the result of crossing the works of Agatha Christie's whodunnits with John Buchan thrillers, while sprinkling in a liberal dash of John D. MacDonald's world-weary cynicism
Tree Frog was written by Martin Woodhouse, and is one of a series featuring the character Giles Yeoman, a research scientist working for the British Government. In this novel, Yeoman is called upon to use his knowledge of hydraulic control systems to examine a crashed unmanned aerial vehicle, and gets drawn into a web of conspiracy, duplicity and misinformation. It's of mild current interest these days given the increasing use of Predators in the War on Terror. 6/10. Tree Frog (New Windmills)