The following is the Sept. 15, 2021, Congressional Research Service report, Navy Lasers, Railgun, and Gun-Launched Guided Projectile: Background and Issues for Congress.
From the report
This report provides background information and issues for Congress on three potential new ship-based self-defense weapons for the Navy—solid state lasers (SSLs), the electromagnetic railgun (EMRG), and the gun-launched guided projectile (GLGP), also known as the hypervelocity projectile (HVP).
The Navy’s proposed FY2022 budget requests research and development funding for continued work on SSLs, but proposes suspending further work on the EMRG and GLGP programs and requests no research and development funding for them.
The Navy installed its first prototype SSL capable of countering surface craft and unmanned aerial vehicles (UAVs) on a Navy ship in 2014. The Navy since then has been developing and installing additional SSL prototypes with improved capability for countering surface craft and UAVs. Higher-power SSLs being developed by the Navy are to have a capability for countering anti-ship cruise missiles (ASCMs). Current Navy efforts to develop SSLs include
- the Solid State Laser Technology Maturation (SSL-TM) effort;
- the Optical Dazzling Interdictor, Navy (ODIN);
- the Surface Navy Laser Weapon System (SNLWS) Increment 1, also known as the high-energy laser with integrated optical dazzler and surveillance (HELIOS); and
- the High Energy Laser Counter-ASCM Program (HELCAP).
The first three SSL efforts listed above are included in what the Navy calls the Navy Laser Family of Systems (NFLoS).
The Navy had been developing EMRG since 2005. It was originally conceived as a naval surface fire support (NSFS) weapon for supporting Marines and other friendly forces ashore. Subsequently, it was determined that EMRG could also be used for air and missile defense, which for a time strengthened Navy interest in EMRG development.
As the Navy was developing EMRG, it realized that the guided projectile being developed for EMRG could also be fired from powder guns, including 5-inch guns on Navy cruisers and destroyers and 155 mm artillery guns operated by the Army and Marine Corps. The concept of firing the projectile from powder guns is referred to as GLGP and HVP.
Download the document here.