type of unit	men	description
Firefighting Platoon	1. 1st. Lt., 28 Enlisted men (1- Staff Sergeant, 4 - Sergeants,  12 T/5s, 5 PFCs, 4 PRVTs) per T/O&E 5-500, 26 July 1944	With 1 CLASS 325 fire truck and 3 CLASS 1000 trailer mounted fire fighting pumpers an Engineer Fire Fighting Platoon fought and suppressed fires in buildings, vehicles, dumps (food, ammuntion, petroleum and chemical warfare), ships, wild lands and if necessary burning aircraft.  Aircraft fire fighting was done principally by Engineer Aviation Fire Fighting Platoons who had the same staffing, but had 1 CLASS 135 fire truck, 1 CLASS 1000 trailer mounted fire fighting pumper and 2 CLASS 1010 trailer mounted fire fighting pumpers.
Airborne Aviation Bn	29 officers, 501 enlisted men	Equipped with light machinery, this unit prepared captured airdromes, usually located behind enemy lines, for early use by Army Air Forces.  It was sometimes flown in to clear landing strips when regular aviation battalions, because of their heavy equipment, could not be used.
Aviation Bn	33 officers, 744 enlisted men	The basic engineer construction unit of the Army Air Forces.  It was completely equipped to construct an airfield and all its appurtenances.  It might also be called upon to camouflage, maintain, and defend airfields.
Aviation Company, Separate	5 officers, 171 enlisted men	Similar in organization to a company of a combat battalion, but with more machinery for runway construction.
Aviation Regiment	66 officers, 1 warrant officer 2,160 enlisted men	This large unit was organized, trained, and equipped in the early days of the defense build-up.  It constructed, repaired, maintained, camouflaged, and defended airfields wherever such work was concentrated in a small area.  The battalions of the regiment were the same as regular aviation battalions.
Headquarters and HQ Co, Base Depot Group	11 officers, 2 warrant officers, 62 enlisted men	Provided the overhead needed to supervise the operations of an engineer base depot group.  Normally such a group was at or near a port of embarkation.  The headquarters and headquarters company with its attached troops operated either the engineer section of a general base depot or an engineer base depot.  One or more of the following units were attached:  base depot company, heavy shop company, platoon or company, gas generating unit, quartermaster truck company.
Base Equipment Company	5 officers, 168 enlisted men	This unit, usually located at or near an engineer depot, made various types of heavy construction equipment available to engineer units on a loan basis.  Skilled operators were sometimes sent with the equipment.
Camouflage Company, Separate	5 officers, 62 enlisted men	Usually assigned to a task force or independent corps, supervised and inspected camouflage work, discipline, and training; experimented with new camouflage methods; and helped troops camouflage their areas.
Combat Battalion	29 officers, 3 warrant officers, 605 enlisted men	This was the Engineer component of the triangular infantry division.  It increased the division's combat effectiveness by means of general engineer work, including construction of roads and bridges, the clearing of mines, and the destruction of obstacles.  The unit thereby helped make it possible for the infantry to    advance, and by laying mines, erecting obstacles, and using demolitions helped the infantry thwart an enemy attack.
Combat Company, Separate	4 officers, 176 enlisted men	Usually employed in improving routes of communication.  The amount of work the company could do with its men and tools was relatively small.
Headquarters and HQ Co, Combat Group	15 officers, 69 enlisted men	The primary mission of this unit was to supervise the operations of corps and army combat engineer troops.  The composition of the group was determined by the engineer mission and the units and facilities available.
Combat Regiment	39 officers, 1 warrant officer, 908 enlisted men	The Engineer component of the square infantry division, the combat regiment performed the same engineer work for the square division that the combat battalion performed for the triangular division.
Headquarters and HQ Co, Construction Group	13 officers, 1 warrant officer, 80 enlisted men	Organized to supervisor the operations of from three to six construction     battalions.
Depot Company	7 officers, 202 enlisted men	Its primary mission was the operation of an engineer depot or other engineer supply point in a theatre of operations.  It sometimes was a part of a large special engineer depot or the engineer section of a general depot; sometimes it operated as a separate engineer supply unit.
Dredge Crew	Varying from 5 officers, 4 warrant officers, 47 enlisted men to 6 officers, 4 warrant officers, 57 enlisted men	This unit dredged rivers, harbors, and channels.
Dump Truck Company	4 officers, 103 enlisted men	Its primary principal mission was to assist other engineer units by furnishing transportation for the movement of heavy materials.  This unit was usually attached to engineer units engaged in road and railroad construction involving earth moving, clearing, grading and paving.
Engineer Squadron	14 officers, 441 enlisted men	This unit, the Engineer component of the cavalry division, did work comparable to that performed by the combat battalion for the infantry division.
Headquarters and HQ Co, Forestry Battalion	8 officers, 2 warrant officers. 82 enlisted men	The headquarters and headquarters company supervised 3 or more forestry companies (each with 5 officers and 150 enlisted men) whose job it was to supply lumber and other forest products from woodlands in or near a theatre of operations.  The companies either set up and operated the sawmills with which they were equipped or they used sawmills already in the area.
Foundry Team	1 officer, 16 enlisted men	This team was capable of producing molten metal in the following quantities:             Cast iron - about 108 lbs per hour Steel - about 100 lbs per hour
General Service Regiment	39 officers, 11 warrant officers, 1,221 enlisted men	Performed general engineer work-especially that requiring a fair amount of skilled labor- throughout the army service area and communications zone of a theatre of operations.  A general service regiment, with its large HQ organization, large number of specialists, and special equipment, plus the fact that it remained a longer time in an area, could undertake extensive and permanent work.  General service regiments could be reinforced with other engineer units.
Heavy Ponton Battalion	12 officers, 462 enlisted men	Transported and maintained four units of heavy ponton equipage, 25-ton M 1940, with which it constructed bridges and rafts, sometimes with the assistance of other engineer troops.  In an extensive river crossing operation, the battalion was attached to a corps to provide a bridge capable of supporting heavier loads.
Heavy Shop Company	6 officers, 165 enlisted men	A semi-mobile unit, the heavy shop company performed fourth echelon maintenance on all equipment for which the Corps of Engineers had maintenance responsibility.  Fourth echelon maintenance included rebuilding a units equipment, overhauling the the attachments and accessories, doing emergency overhaul of major units, and recovering equipment from the battlefield, reclaiming, and salvaging it.
Light Equipment Company	4 officers. 114 enlisted men	Furnished supplementary equipment with operators to engineer combat battalions and operated as a replacement pool for construction equipment.  Light equipment companies were attached to corps or army.
Light Ponton Company	6 officers, 215 enlisted men	Organized and trained to maintain its stream-crossing equipage, to construct floating bridges and rafts, to guard and maintain completed bridges, to regulate traffic thereon, and to dismantle bridges and rafts.
Maintenance Company	6 officers, 185 enlisted men	A mobile unit, the maintenance company had as its primary mission third echelon maintenance of all equipment, including that  used by other arms and services, for which the Corps of Engineers had maintenance responsibility.  Third echelon maintenance included the making of minor repairs on a unit's equipment.
Map Depot Detachment	1 officer, 11 enlisted men	Received, stored, and issued maps.  This unit was adequate to provide map depot facilities for one base section.
Model Making Detachment	1 officer, 18 enlisted men	Constructed scale models of terrain to assist air and ground forces in planning. Normal attachment was to a topographic unit since photo processes were used in model making.  The unit was assigned as directed by the commander of the theatre of operations.
Parts Supply Company	6 officers, 168 enlisted men	Established and operated an engineer spare parts supply depot and other spare parts supply agencies.  This company was a non-mobile unit which operated as part of the engineer depot organization of a base installation.  It could not operate as a separate supply unit unless it was furnished with motor transportation.
Petroleum Distribution Company	7 officers, 209 enlisted men	The primary mission of this unit was to design, construct, operate, and maintain military pipeline systems for transporting, distributing, and storing gasoline in a theatre of operations.
Pipeline Operating Detachment	1 officer, 24 enlisted men	Organized and equipped to operate a bulk petroleum terminal consisting of 50,000 barrels of tankage with the necessary tanker unloading facilities and a three-pump station pipeline system.
Photomapping Team	2 officers, 78 enlisted men	This team was equipped to perform original topographic mapping from aerial photographs.  It was normally attached to a topographic unit having planning, computing, and reproduction facilities; it was sometimes used to increase the capacity of a base topographic battalion.