San Diego (Jan. 31, 2006) – The Seahorse-class Autonomous Underwater Vehicle (AUV) is maneuvered into position in Sea Fighter’s (FSF-1) mission bay during launch and recovery testing. At 28 feet, six inches, and weighing 10,800 pounds, Seahorse is an untethered, unmanned, underwater robotic vehicle, capable of pre-programmed independent operations. The Office of Naval Research (ONR) sponsors the demonstrations. U.S. Navy photo by Mr. John F. Williams (RELEASED) (From Navy News Stand)
The Seahorse (more pictures here) was originally developed for the Naval Oceanographic Office (NAVOCEANO) by the Penn State University Applied Research Laboratory as an economical, long-endurance, unmanned underwater vehicle for oceanographic surveying and bottom mapping. The Navy, as is often the case, has a few ideas of its own for the vehicle.
SEAHORSE construction is modular to facilitate field maintenance, rapid mission turnaround, and payload flexibility. With an integrated afterbody for propulsion and hydrodynamic control, plus variable ballast systems fore and aft, the UUV can execute a variety of high-level commands, such as maintaining a constant depth, course, and speed; navigating between waypoints; and conducting search and survey patterns. Typical mission operating depths range from 15 to 1,000 feet, with endurance up to 72 hours. SEAHORSE vehicles are 28 feet long, slightly more than three feet in diameter, and weigh 10,500 pounds. Standard alkaline batteries (D-cells) power the vehicle, allowing a 300-mile range. NAVOCEANO plans to transition to rechargeable lithium-ion battery technology in the near future.
In standard operations, the Seahorse is launched from a T-AGS 60 Pathfinder-class ship. The most recent pictures show test operations on the FSF-1 Sea Fighter X-Craft. Test launches from Trident missile tubes have been performed, as well. The Seahorse’s diameter prevents it from being launched from standard torpedo tubes (maximum of 21 inches).
The Seahorse’s primary survey mission could be very valuable to the Navy in a supporting role, especially in the littorals, but the modular nature of the vehicle and rapidly-advancing technology could broaden the scope of the Seahorse’s mission extensively. At worst, it will serve as an advanced test-bed for the Navy’s wide range of unmanned underwater vehicle programs. These include the Long-Term Mine Reconnaissance System (LMRS), a torpedo tube-launched AUV for mine detection and countermeasures, the Mission-Reconfigurable UUV (MRUUV), which would be launched from submarines or surface ships and carry array of sensor payloads for performing a variety of information-gathering missions, the Advanced Development UUV (ADUUV), the large-diameter UUV (LDUUV), Remus (Remote Environmental Measuring Units), BPAUV (Battlespace Preparation Autonomous Underwater Vehicle), and Manta.
For more on this alphabet-soup, see Unmanned Vehicles for U.S. Naval Forces: Background and Issues for Congress (.pdf, particularly pg. 4), RECENT U.S. NAVY UNDERWATER VEHICLE PROJECTS (.pdf), and THE LOWER DEPTHS: Navy Plans for Unmanned Undersea Vehicles on Military.com.
More-direct support for military operations, such as real-time intelligence, surveillance and reconnaissance. resupply of special forces ashore, or even direct attacks against sea or short targets with weapons, are in the cards for these robot subs. The Seahorse will lead the way for follow-on vehicles, and might even get a chance to contribute a bit itself.