United States Army Field Manuals are published by the United States Army‘s Army Publishing Directorate. As of 27 July 2007, some 542 field manuals were in use. They contain detailed information and how-tos for procedures important to soldiers serving in the field. – Wikipedia
These manuals are a wonder for writers researching multiple subjects whether writing about war/battles or not. I’ve used the first aid manuals for years because they show the basic techniques that can be applied in the field by non-medical personnel. If one of your characters breaks a leg, for example, the field manual shows you what first aid to use.
The manuals can be found in a variety of places, some for sale on Amazon, others are various free sites. Click on the word “Wikipedia” after the quote above for an overview. One handy downloading source (various formats) can be found at the US Military Manual Collection website. There’s quite a list here.
There’s good stuff (e.g. Sniper Training) for writers doing novels about battles and black ops. For general writing, there’s Map Reading and Land Navigation (very good: used this in ROTC and Scouting), Basic Cold Weather Manual, Carpentry, Welding, Diving.
Maybe you’ll find something here that helps your research.
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