Point Loma Navy Electronics Laboratory

[Subdeacon Joe]

Iowa class model at the antenna range, Pt Loma, Navy Electronics Laboratory. The model is made of wood and plated in brass. The model is 18'6" long, 27.5" wide and weighs 550 pounds.

 

1949 Press Release - 

   In planning communications systems for ships at sea, Navy scientists seek to design shipboard antennas capable of sending out substantially the same amount of energy on all directions.

 

   This problem is attacked at the US Navy Electronics Laboratory, San Diego, California, by the use of miniature ships whose topside structures are precisely scaled counterparts of full-sized naval vessels. These models make it possible to conduct investigations of shipboard antenna directivity under controlled conditions on land. Scale factors of 1/12, 1/24, and 1/48 are used in the studies and are applied both to the construction of the miniature ships and to the radio wavelengths most commonly encountered in shipboard communications.

 

   In practice, the scale model is mounted on a turntable and rotated over a mesh of hardware cloth while it antennas are supplied with energy at the correct radio frequency. The hardware cloth simulates the conductivity of the ocean at regular communication frequencies. The radiated energy is received and its intensity measures at special stations on the rim of the "ocean". These measurements give radiation characteristics of the small antenna, and by extension, the performance of a full size antenna aboard a full size ship at communication frequencies.

 

  Each ship is electronically complete down to the waterline. Each has operational antennas for transmitting and receiving radio signals at varying frequencies. Because metallic ship environments distort and alter the radiations from antennas, and obstructions topside provide added interference, antenna efficiency usually depends upon the placement, design, and number of the antennas.

 

   The Laboratory tests the efficiency of a particular antenna design by sending and receiving signals in all frequencies while the ship model turns through the 360° of azimuth on a 22-foot turntable in the center of a 160-foot lead and wire-coated field. The coating provides environmental conditions roughly approximating those of the ocean.

 

   An actual ship could make only a limited number of turns in a day, with consequent loss of operational time, manpower tieup, and interruption of other training. Moreover, changeable weather conditions would prohibit testing under controlled physical conditions, as is possible on a controlled range.

 

   A further great advantage of the range is the design and test of communications systems as an aid to ship preliminary design. Technically, the artificial ocean is a conducting ground plane, and the experiments measure on the ship models vertically polarized components of horizontal-plane patterns in the 96 to 1440 megacycle range, simulating the 2- to 30-megacycle band.

 

   A two-axis free space mount, available for measurement of zenith coverage patterns in the 1000 to 3000-megacycle range, can accommodate scale models (usually 1/4 scale) of ship masts and superstructures. Use of a wire mesh ground plane of about 40,000 square feet with five 90-foot wood poles permits realistic full-scale tests of simulated ship antenna systems, and an additional 120-by-150 wire mesh ground plane has a rotating antenna mount for development and test of specific antennas for ship and shore applications.

 

   Ship communication mock-up facilities in the antenna range building make possible the study and development of complete ship radio communication systems under conditions simulating those aboard ship. Improvements now under way at the ship model range will permit absolute measurement of antenna patterns and extension of measurement to evaluation angles above the horizon.

 

   Nearby microwave facilities include a range for rapid and accurate determination and recording of the free space radiation patterns, impedance, and gain characteristics of microwave antennas in the frequency range from 1000 to 10,000 megacycles.

 

   NEL engineers must study as many as 3,000 to 5,000 radiation patterns for each new ship design. To lighten their workload the antenna range specialists recently devised a Pattern Analyzer Computer (analog to digital) equipment which is used to determine values required from the antenna patterns by an IBM computing machine.

 

The history of US Navy electronic technology at Pt. Loma

 

The history of electronic technology began on Pt. Loma a long time before the establishment of the laboratory here in 1940. On May 12, 1906, a chief petty officer and two sailors drove a horse-drawn wagon to the downtown pier and loaded up a massive 5-kw. transmitter/receiver, the state-of-the-art in communications. This was the new age of "wireless radiotelegraphy," which the Navy would eventually shorten simply to "radio." Many hours later, in the little station house they’d set up on top of the hill, the equipment had been installed. The chief sat down and tapped out a hopeful message to the Mare Island Naval Radio Station. He was hopeful, because the distance record for Navy wireless communication at the time was about 125 miles, and Mare Island was 500 miles away. He was stunned by an immediate reply, and in celebration commissioned the facility as Navy Radio Station Pt. Loma.

 

On June 1, 1940, Secretary of the Navy Frank Knox established the Navy's first laboratory on the West Coast, the U.S. Navy Radio and Sound Laboratory. Its mission was to perform research and development in communications and radio propagation. In 1943, a second West Coast laboratory was established in the high desert at Inyokern, Calif., the Naval Ordnance Test Station (NOTS), charged with improving naval weapons systems, particularly those dropped from aircraft. NOTS became the Naval Undersea Warfare Center, the Naval Undersea Research and Development Center, and the Naval Undersea Center (NUC).

 

The naming history and name changes across seven decades is convoluted, so try to follow along. (see the SSC San Diego Org History flow chart in photos for more subornate commands involved and integrated along the way).

 

U.S. Navy Radio and Sound Lab (NRSL)(1940) Who also worked together with UCDWR (University of California Division of War Research) 

 

U.S. Navy Electronics Laboratory (NEL)(1945) UCDWR and NRSL combined to create NEL

 

Naval Command Control and Communications Laboratory Center (NCCCLS) (1967)

 

Naval Electronics Laboratory Center (NELC) (1968)

 

Naval Ocean Systems Center (NOSC) - On March 1, 1977, NELC and NUC were consolidated to form the Naval Ocean Systems Center (NOSC)

 

Naval Command, Control and Ocean Surveillance Center (NCCOSC) RDT&E Division (1992) combined to become NRaD

 

Space and Naval Warfare Systems Center San Diego (SSC SD) (1997)

 

Space and Naval Warfare Systems Center Pacific (SPAWAR Systems Center Pacific or SSC Pacific) (2008)

 

Naval Information Warfare Center(NIWC) (2019)

 

[Abilene Slim SASS 81783]

What became of the models?

[Subdeacon Joe]

2 hours ago, Abilene Slim SASS 81783 said:

What became of the models?

 

One comment in the FB thread:

 

"When you drive by the lab on the way to Cabrillo National Monument there are a number of these models still sitting in the yard outside the lab.  Many years ago the Maritime Museum borrowed one for a model exhibit, it was an aircraft carrier and as I recall it was over 20 feet long!"

 

And another 

 

USS Albany class model found in San Diego a few years ago. Restored and on display in Albany NY

 

Here's the link to that thread 

 

https://m.facebook.com/story.php?story_fbid=pfbid0mMZy9SWfg4JGzu2zFqGQ2kJ7W1nzBszJoCPUs3uoWfWJMMBjZLEGoKo1k4X6Czjel&id=100075613827574&mibextid=Nif5oz

 

[Sedalia Dave]

They are still in the model business. Meet the Navy’s only model ship builder

 

 

Island of the USS Gerald Ford

 

 

Some of the older models

 

 

[Sedalia Dave]

 

 

Popular Mechanics article from April 1959. Very informative.