Lessons Learned. Headquarters, 864th Engineer Battalion (Const) Open PDF Document Details Document Type Technical Report Publication Date Jul 31, 1968 Accession Number AD0843469 Entities Organizations Adjutant General's Corps Tags Communities of Interest Biomedical Energy and Power Technologies Human Systems Weapons Technologies DTIC Thesaurus Topics Air Conditioning Concrete Construction Contractors Drilling Electrical Equipment Engineers Groundwater Helicopters Joints Lessons Learned Maintenance Masonry Materials Medical Personnel Military Equipment Training