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What is the most accurate expression of the state of locomotives that were hit in strafing runs – destroyed, out of service or damaged? As far as I am concerned and in general, the correct answer is out of service. The reason is simple: This describes what really happened to these locomotives and was, by the way, widely used in police and railroad administration reports (dienstfähig or betriebsfähig in German).
As steam locomotive was in principle similar to a pressure tank even a single bullet penetrating the boiler or another crucial component of the engine caused that steam pressure to decrease immediately, which eventually brought the locomotive to a halt and it had to be towed to the repair shop. The period of maintenance obviously varied depending on how seriously the locomotive had been damaged.
Many locomotives that were initially considered only damaged (i.e. were able to keep on moving from the accident site) were subsequently, after further examination, denoted out of service. There is no statistics available to confirm this presumption, which is based on the "CVs" of locomotives kindly provided by blog readers.
On the other hand, the only case of total loss of a locomotive due to action of fighter-bombers I am familiar with occured at a RR station north of Pilsen on April 18, 1945. The others remained in service for twenty years, for instance, after being fixed.
U. S. fighter units made distinction between destroyed and damaged locomotives in mission reports but it's not clear (at least to me) whether pilots were really able to judge whether a particular locomotive was destroyed or damaged from their view when strafing or leaving the target area. I haven't found out any criteria for this classification.
