Battery AMTB - Cabrillo

Fort Calendar

Fort Blogs

Battery AMTB - Cabrillo (1943-1946) - Battery AMTB - Cabrillo was a World War II, rapid fire, 90mm gun battery on Fort Rosecrans, San Diego County, California. Battery construction started 29 Jun 1943, was completed 26 Aug 1943 and transferred to the Coastal Artillery for use 14 Dec 1943. Deactivated in 1946.

World War II

Part of the Harbor Defense of San Diego.

The AMTB battery at Point Loma consisted of two 90mm guns mounted on 90mm M3 fixed gun mounts and two 90mm guns mounted on 90mm M1A1 mobile gun mounts. Concrete pads were provided for both fixed guns and wooden gun platforms were provided for the mobile guns. The mobile guns were not normally emplaced. Two earth covered concrete magazines provided protection for the ammunition. Electric power was provided by M-7 portable generators.

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 or 4.5 miles. Each weapon required a crew of 15, 9 men in the gun squad and 6 men in the ammunition squad.

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 - Cabrillo Armament** (edit list)
Empl No	Caliber Type	Barrel Length	Model	Serial No	Manufacturer	Carriage	Service Dates
1	90mm Rifle	186.15"	M1	3031	Wheland	Pedestal Mount, M3, #T3-92, GM	1943-1946
2	90mm Rifle	186.15"	M1	15327	GM	Pedestal Mount, M3, #T3-201, GM	1943-1946
Source: RCW Form 1, 12 Apr 1944, CDSG, 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

Battery AMTB - Cabrillo Plan

Current Status

Part of the Cabrillo National Monument, San Diego County, California. Battery destroyed, no period gun or mounts in place.

Location: Cabrillo National Monument, San Diego County, California. Map point is approximate.

Maps & Images Lat: 32.667676 Long: -117.243798

Street map from Google Maps or Yahoo! Maps
Topographic map from TopoQuest
Satellite image from Google Maps or Microsoft Virtual Earth
Wiki Mapping from WikiMapia
Mapping from Bing
Mapping from Bing Birdseye
Elevation: 39.9'

Sources:

U.S.Army, Supplement to the Harbor Defense Project of San Diego, (HDSD-AN-45), 1 Jul 1945, CDSG

Links:

CDSG

Visited: No