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Review title: Ancestor of the U-2 spy plane.
Product review: During WW2, the German Research Institute for Sailplanes (gliders) developed a very high altitude photo-reconnaissance aircraft, which was basically a very large sailplane with large wings and a rocket motor to boost it into the stratosphere. By flying very high over enemy territory the DFS-228 could not be intercepted by any of the fighter aircraft of the day. The same concept was used by Lockheed when it developed the Lockheed U-2 spy plane in the 1950's. This book is a nice bit of techie history and is another interesting example of aviation technology that was "borrowed" by the USA after WW2.
