Military

William B. Morgan Large Cavitation Channel (LCC)

This detachment, located on a 94-acre site on President's Island near Memphis, became part of the David Taylor Research Center (DTRC) in 1988. In 1992, DTRC consolidated with NAVSSES to become the Naval Surface Warfare Center, Carderock Division. This Detachment includes a 500,000 square foot industrial facility with a 10-story clear space and 35,000 square feet of office space. This detachment was developed as the operating site for the Large Cavitation Channel. Programs in the LCC have ranged from basic research to direct Navy ship applications, including SSN 21, NSSN, and LPD 17.

The William B. Morgan Large Cavitation Channel (LCC) is one of the world's largest and most technically advanced water tunnel facilities. It is capable of testing all types of ship and submarine propellers and propeller-hull interactions with model scales sufficiently large to match the largest towing and turning basins in the world. The tunnel test section has a cross-section area of 100 square feet (10 feet by 10 feet) and can accept models up to 40 feet in length.

Operational since 1991, the LCC was designed as a variable pressure, recirculating, cavitation tunnel with a very low acoustic background level. The LCC provides significant cost savings for testing large-scale models of advanced ship and submarine system designs and full scale torpedoes in a controlled environment. The LCC employs advanced hydro-acoustic silencing techniques for reducing acoustic reverberation introduced by the water flow of the tunnel. Commercial uses of this facility include maritime shipping industry applications.

Its sophisticated design permits the U.S. Navy to measure submarine and surface ship power, efficiency, and propeller noise by using models in a controlled but realistic environment. As a model is held stationary, water flow at speeds up to 35 knots combines with variable pressure to allow simultaneous measurements of propeller cavitation and acoustics from the models propulsion, hull, and appendages. Pressure in the LCC test section ranges from less than atmospheric to four times atmospheric pressure, the equivalent of water approximately 100 feet deep.

The Large Cavitation Channel is a vertical plane, closed recirculating 1.4 million gallon, variable speed, variable pressure, channel with lower half submerged in 2.5 million gallon water filled trench, plus numerous other acoustic treatment features, 6:1 contraction ratio, aeration/deaeration system, filter system (5-micron), temperature control, stainless steel shell, models mounted on large removable test top, low turbulence (0.1%). High speed capability up to 50 ft/s. Large test chamber with 10 ft by 10 ft cross-section and a 13.1 m (43 ft) working length.

The Division executed a real estate exchange with the Memphis and Shelby County Port Commission that provides an acoustic buffer around the Navy's Large Cavitation Channel (LCC) and avoids future maintenance costs for the site. The exchange was effective on May 19, 2000, and was the result of a six-year real estate process requiring legislation and extensive negotiations. The acoustic buffer gained in the real estate exchange will ensure a quiet environment to support LCC acoustic testing in the future.

In 1993, the Navy learned of plans to expand the industrial area of President's Island to the west of the LCC. This potentially threatened the LCC's acoustic environment should new roadways or noise-generating businesses locate adjacent to the LCC. To protect and preserve the LCC's quiet testing environment, options to control the area around the LCC were explored, such as purchasing additional property or obtaining restrictive easements to control the property's use.

The NSWCCD Memphis Detachment is located on a former commercial, industrial site used to produce pressure vessels in excess of 1,000 tons. The LCC, itself, was dedicated in 1990, and NSWCCD continued to lease the site the next few years. In early 1994, the Navy exercised an option to purchase the entire 90-acre site, which includes a large waterfront facility with a 1,250-ton crane and access to the Mississippi River. However, a 27-acre parcel comprising the waterfront and large-capacity crane was not required to support the LCC's mission. Later in 1994, the Memphis and Shelby County Port Commission expressed an interest in operating the site's waterfront facility to boost commerce and the economy in the Memphis/Shelby County area. This provided a "win-win" opportunity to acquire the acoustic buffer the LCC needed, while avoiding future maintenance costs.

Under the land exchange, title to the 27-acre waterfront area was transferred to the Port Commission, which will operate the facility as a public terminal under safeguards to prevent interference with LCC testing. In exchange, the Division acquired restricted easements on over 70 acres of the Port's property adjacent to the LCC to prevent interference with Navy testing. These restricted easements serve to provide a 1,000-foot acoustic barrier on each side of the LCC, without the Navy having to acquire any additional property with its associated costs and responsibilities. In addition, certain terms of the exchange allow for the Navy's continued access to the waterfront and crane should those needs arise.