Fort Trumbull in New London in New London County, Connecticut — The American Northeast (New England)
Periscope Test Facility
Building 94
Photographed By Bill Coughlin, October 9, 2011
1. Periscope Test Facility Marker
An industrial-looking building with few windows stood on this site directly in front of the fort from the 1770s until 1999. It was designed specifically for top-secret work in periscope technology.
Originally, periscopes were simple tube-shaped optical devices that permitted a submarine crew to see above the surface when the ship was underwater. The research that took place in this building was instrumental in developing increasingly sophisticated types of periscopes, incorporating cameras and high-tech antennas.
The navy expanded a former machine shop in 1977 and added a tall tower to form this building. Nine years later, the navy enlarged the tower and added a second floor. The seventy-five-foot-high tower had room to test six periscopes in a fully extended, vertical position. Researchers could raise three periscopes to project above the building through trap doors in the tower roof. In this position the periscopes could transmit and receive communications from satellites, as well as receive radio, radar, and optical signals from various other sources.
Erected by Fort Trumbull State Park.
Topics. This historical marker is listed in these topic lists: Communications • Science & Medicine • Waterways & Vessels. A significant historical year for this entry is 1999.
Location.
this page online
Other nearby markers. At least 8 other markers are within walking distance of this marker. Magnetic Silencing (within shouting distance of this marker); “The Arches” (within shouting distance of this marker); Scientific Research (within shouting distance of this marker); Post Civil War to 1910 (within shouting distance of this marker); Coast Guard (within shouting distance of this marker); Civil War (within shouting distance of this marker); “Aim, Load, Fire” (within shouting distance of this marker); Merchant Marine (within shouting distance of this marker). Touch for a list and map of all markers in New London.
More about this marker. Pictures of the building appear at the bottom of the marker. On the left is photograph of “The periscope test facility seen from the water.” Next to this is an interior photo with the caption “The lower floor of the test facility contained three steel racks that held periscopes in a horizontal position. This allowed removal of the inner equipment from the periscope tube for testing, adjustment, and repair. Work on individual components
Photographed By Bill Coughlin, October 9, 2011
2. Periscope Test Facility Marker
Also see . . . History of Fort Trumbull. Friends of Fort Trumbull. (Submitted on October 16, 2011, by Bill Coughlin of Woodland Park, New Jersey.)
Photographed By Bill Coughlin, October 9, 2011
3. Marker at Fort Trumbull State Park
Photographed By Bill Coughlin, October 9, 2011
4. Periscope Test Facility Marker
Credits. This page was last revised on May 6, 2023. It was originally submitted on October 16, 2011, by Bill Coughlin of Woodland Park, New Jersey. This page has been viewed 542 times since then and 12 times this year. Photos: 1, 2, 3, 4. submitted on October 16, 2011, by Bill Coughlin of Woodland Park, New Jersey.
