Battery AMTB 21 - Rockaway Point (1943-1946) - Battery AMTB 21 - Rockaway Point was a reinforced concrete World War IIAMTB rapid fire 90mm gun battery on Fort Tilden, New York. Battery construction started 3 Feb 1943, was completed 15 Mar 1943 and transferred to the Coast Artillery for use 15 Mar 1943 at a cost of $ 15,890.93. Deactivated in 1946.
Part of the Harbor Defense of Southern New York.
The AMTB battery at Rockaway Point consisted of two 90mm, M1 guns mounted on 90mm, M3 fixed gun mounts and two 90mm M1 guns mounted on 90mm, M1A1 mobile gun mounts. Two concrete pads for the fixed guns were laid just back of the beach at Rockaway Point, Queens County, New York. The two mobile guns were emplaced alongside the fixed platforms on timber firing platforms. 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.
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 21 - Rockaway Point Armament(edit list)
Source: RCW Form 1, 21 Jun 1943, 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, 207-208
Battery AMTB 21 - Rockaway Point PlanBattery AMTB 21 - Rockaway Point Fixed Mount PlanBattery AMTB 21 - Rockaway Point Mobile Platfom Plan