Battery AMTB 911

Battery AMTB 911 (1943-1946) - Battery AMTB 911 was a reinforced concrete World War II AMTB rapid fire 90mm gun battery on Fort Terry, Plum Island, Suffolk County, New York. Battery construction started 18 May 1943 was completed on 28 Jun 1943 and transferred to the Coast Artillery for use 20 Dec 1943. Deactivated in 1946. Battery AMTB 911 History Part of the Harbor Defense of Long Island Sound. The AMTB battery at Pine Point consisted of two 90mm guns mounted on 90mm M3 fixed gun mounts and two 90mm guns mounted on 90mm M1A1 mobile gun mounts. Concrete firing platforms were laid for both of the fixed guns. The battery had a dual mission of defense against fast enemy motor torpedo boats and enemy aircraft. The effective range of the guns was about 8,000 yards. Each weapon required a crew of 15, 9 men in the gun squad and 6 men in the ammunition squad. Ammunition was stored in igloo type magazines behind the batteries. Power was provided by two M-7 portable generator sets in revetments. AMTB Front View AMTB Interior View AMTB Side View AMTB Back View The above photos were taken at Fort Monroe, Battery Parrott From FM 4-91: "This weapon consists of the 90-mm gun M1 and top carriage M1A1 on the 90-mm gun mount M3. The mount M3 is of the turret type, the shielding being constructed of boiler plates. This boiler plate shield provide fragmentation protection only. No shielding is provided at the rear due to the requirements for service of the piece. A sighting port in the shielding in front permits sighting in direction by the gun pointer." References: FM 4-91 - 90-MM Gun, Fixed Mount Service of the Piece FM 4-126 - Antiaircraft Artillery, Service of the Piece, 90-mm Antiaircraft Gun TM 9-373 - 90-mm Gun M1 and 90-mm Gun Mount T3 (M3) Battery AMTB 911 Armament (edit list) Empl No Caliber Type Barrel Length Model Serial No Manufacturer Carriage Service Dates Notes F1 90mm Rifle 186.15" M1 6932 GM Pedestal Fixed Mount, M3, #117, GM 1943-1946 F2 90mm Rifle 186.15" M1 6699 GM Pedestal Fixed Mount, M3, #25, GM 1943-1946 M1 90mm Rifle 186.15" M1 ? Unknown Mobile Mount, M1A1, #?, Unknown 1943-1946 M2 90mm Rifle 186.15" M1 ? Unknown Mobile Mount, M1A1, #?, Unknown 1943-1946 Source: RCW Form 1, Aug 1944, Coast Defense Study Group, Berhow, Mark A. ed, American Seacoast Defenses: A Reference Guide, 2nd Edition, CDSG Press, McLean, VA, 2004, ISBN 0-9748167-0-1, pages 80-81, 206 Battery AMTB 911 Plan Current Status No period gun or mounts in place. {"selectable":false,"width":"500"} Location: Plum Island, Suffolk County, New York. Map point is approximate. Maps & Images Lat: 41.165236 Long: -72.198785 Multi Maps from ACME Maps from Bing Maps from Google Elevation: 11.67' Sources: U.S.Army, Supplement to the Harbor Defense Project of Long Island Sound, (HDLIS-AN-45), 15 Feb 1945, CDSG Links: Coast Defense Study Group, CDSG Press, CDSG Digital Library Visited: No Battery AMTB 911 Picture Gallery Click on the picture to see a larger version. Contribute additional pictures - the more the better!