From the site military.com some examples of Engineer Battalion CoA:s. As can be seen the Engineer Corps colours of Argent and Gules dominates as regarding colours.
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401st Engineer Water Supply Bn. The Water Supply Role has ben apptly symbolised by an ancient Roman Aquaduct. As the Battalion served in Italy during WW 2 the Aquaduct can also be said to represent this service. Not seen here are the Motto: Favet Fortuna Labori (Fortune Favors Labor).
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12th Engineer Squadron. Originated as the 318th Engineers raised in 1917 and served with the 6th Division during WW 1. Become 12th Engineer Sqn during the 1930ies and disbanded 15 July 1940. The indented rodure symbolises field fortifications (Trenches). The Bend is taken from the Arms of Alsace and symbolises service there during WW 1. The Crest symbolises the Baptism of Fire at Bellefontain. The Squadron also hade the motto Ire paratus (Prepared to go). Arms approved 5 september 1929.
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983rd Engineer Bn. Activated in 1943 and served in Europe during WW 2. The brick backgrund symbolises the Construction Role of this Battalion. The wavy bend symbolises service in the Rheinland part of Germany. The Sable fesses symbolises Campaign honours earned in WW 2. The Battalion also had the Motto: Complere (To complete). As a reserve unit the Battalion also had the Reserve Unit Crest of the Lexington Minuteman. Approved 5 mars 1953.
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841st Engineer Aviation Battalion. Activated 1942 and served in the Pacific Teather during World War II as a Aviation Engineer Battalion. Later served in the same role during the Korean War. This is symbolised by the Stylized Airfield and the Waves in the Coat of Arms approved 2 september 1952 with the Lexington Minuteman Crest of the Reserve and the Motto: Build, Maintain, Defend.
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844th Engineer Aviation Battalion. Activated in 1942 and served in Europe during World War II, later allocated to the Organized Reserve with HQ Memphis, Tennessee. Arms approved 8 Decemebr 1952, with the Lexington Minuteman as Crest and the Motto: Terra ad Caelum = Through Earth to the sky. The Propeller denotes the Aviation support role, the red fields the Engineer role. The Ermines symbolizes service in Europe.