The Germans famously used the Spanish Civil War to test out many of their military aircraft. This book looks at the two experimental units that first used most of the bomber and fighter types to see service in Spain, tracing their activities on an almost day-by-day and aircraft-by-aircraft basis.
I don't agree with the author's decision not to discuss Guernica, claiming that it falls outside the scope of the book. That is exactly the sort of topic that needs to be addressed in any history of any unit that was involved in the attack, and refusing to discuss it can only raise suspicions, as well as reducing the value of the work. Elsewhere their actions are put into the context of the wider battle, rather going against their own argument.
The very details approach is possible because neither unit contained many aircraft, and nor did they last for very long before their aircraft went to non-experimental units. It also allows the author to look at every aircraft loss.
These units helped test the aircraft that did o much damage in 1939-41, and those that didn't make the cut, so we see details of the Bf 109 and the He 112, the He 111, Do 17 and Ju 86. The pictures this give us a rare view of some of the less familiar aircraft (in particular the He 112), as well as of very early versions of the more famous aircraft.
This is a useful reference work, and tells the story of an early stage in the combat history of these famous German aircraft, but it would have been stronger if Guernica hadn't been side-stepped.
Part I: VJ/88 Versuchsjagdgruppe 88
Part II: VB/88 Versuchsbomberstaffel 88
Author: Rafael A. Permuy Lopez & Lucas Molina Franco
Year: 2017 edition of 2013 original