Frequently Asked Questions: Electromagnetic Railgun
Frequently Asked Questions: Electromagnetic Railgun
Q1. What is a railgun and how does it work?
A1. An electromagnetic railgun uses electrical energy to accelerate projectiles to extreme velocities. Railguns do not require chemical propellants to fire the round or explosives to create an explosive effect on impact -- thereby freeing magazine space for other mission areas or additional projectiles. The high-velocity kinetic impact of the round is so great that even a solid metal round can have an explosive effect. In addition, electromagnetic guns provide a highly consistent and uniform propulsion that allows for much greater accuracy.
Q2. Why is this technology being pursued by the Navy?
A2. The system has the potential to provide responsive, long-range, accurate, high-volume naval surface fire support to U.S. Marine Corps units. It also is envisioned that railguns will also be able to engage surface targets in direct-fire mode. It is estimated that a railgun will be able to fire 6 to 10 rounds per minute. The railgun will offer numerous advantages over conventional naval gunfire systems. Most important is an extremely long range, which could extend more than 200 nautical miles. The current Mk 45 5-inch/54 naval gunfire system currently used for naval surface fire support has a maximum range of slightly more than 13 nautical miles.
Q3. At what stage is the Navy’s railgun program in development?
A3. The Navy’s railgun program is currently in the science and technology phase of development. The Office of Naval Research (ONR) has program lead at this stage of development.
Q4. Are there any prototypes in development?
A4. BAE Systems and General Atomics are currently under contract with ONR as part of the Innovative Naval Prototype Program. Under this 30-month phase, BAE Systems and General Atoms are taking the state-of-the-art electromagnetic railgun technologies through technology maturation and developing a 32-MJ railgun. Thirty-two megajules is equivalent to a firing speed in the range of Mach 7 or seven times the speed of sound. This will be an intermediate step on the road to a 64-MJ Tactical System capable of deployment on board naval surface combatant ships. Delivery of the BAE system was in September 2007.
Q5. How long before a weapon system is fielded in the fleet?
A5. It is estimated that is would take at least another 15 years to field a viable railgun weapon system in the fleet.
Q6. What are some of the advantages of railguns?
A6. Railguns offer numerous advantages over conventional naval artillery:
* Extended range – Railguns ultimately will be capable of engaging targets at distances in excess of 200 nautical miles. Currently, the Mk 45 5-inch/45 naval gunfire system has a range of slightly more than 13 nautical miles.
* Higher velocity – Railgun rounds will achieve hypersonic speeds in excess of mach 7 (5,550 miles per hour). Railguns can provide more responsive fires than current naval gunfire systems, cruise missiles, or aircraft on strip alert.
* Safer ammunition handling – Without the need for explosive propellants or warheads, there is no danger of accidental explosions during ammunition loading and magazine storage.
* More rounds aboard ship – Because railguns eliminate the need for explosive propellants, logistics for the weapons system is greatly simplified. The additional space can be used for additional rounds or for other uses in the ship. This means a ship can stay on station longer, providing fire support for ground forces ashore.
* High angle of trajectory - Because railguns can fire into the stratosphere, they have a high angle of fire that allows them to engage targets on the reverse slopes of hills and mountains along the gun target line. This is an advantage over current naval surface support systems, which have relatively flat fire trajectories and consequently have a very limited capability to engage targets on reverse slopes in defilade.
Q7. What are the specific technological applications or material that allow railguns to work?
A7. We cannot discuss specific technical details for reasons of national security and classification.
Q8. How do railgun projectiles destroy their targets?
A8. Railgun projectiles destroy targets by kinetic energy only. The tremendous velocity of the round on impact releases enough kinetic energy that explosive rounds are not necessary. This prevents the danger of dud rounds being left in place after a battle that would endanger civilian population after the conflict has ended.
Q9. What is the Navy’s budget for railgun development? How much has it cost already?
A9. The total budget for ONR’s Innovative Naval Prototype railgun program currently is $237 million from FY 06-FY-11.
Q10. What types of targets can the EMRG be deployed against?
A10. Currently, plans call for developing three different rounds for the EMRG: a unitary round for engaging “hard” targets such as prepared positions, bunkers, and buildings; a rod-dispensing round for vehicle targets; and a pellet-dispensing round for personnel targets.
Q11: What are the Navy’s partners on this project?
A11. The primary partners are:
* Charles Stark Draper Lab, Inc.
* General Atomics
* Department of Energy (Lawrence Livermore National Laboratory)
* U.S. Naval Academy
* Naval Postgraduate School
* Naval Sea Systems Command (PMS 500)
* NAWC -- Rhode Island
* NSWC -- Carderock
* NSWC -- Dahlgren
* The United Kingdom
Q12: Is this system being developed for any specific future naval platform?
A12. No. With the planned timeframe of having a deployable weapon system by 2020-2025, we are working on understanding railgun system impacts for ships of different sizes. Integration could occur on new vessels or by retrofitting on existing platforms.
Q13. What are the major scientific hurdles to making such a weapon possible?
A13. The most important developments that will take place during the lifetime of the railgun Innovative Naval Prototype program fall into four key categories: the materials that will comprise the bore and containment system of the launcher; the projectiles; the pulsed-power network; and ship integration.
Q14. Will the projectile have any internal guidance system?
A14. Yes, the projectile will have a guidance system.
Q15. How does the gun’s power (range/velocity) compare with common weapons used for the same general purpose?
A15. See diagram showing comparison with current and historical naval guns. Compare with SR-71 (mach 3.5 maximum -- 2,500 mph) and launch of the Space Shuttle (two minutes into the ascent, the space shuttle is about 45 kilometers [28 miles] above the earth's surface and is traveling nearly 5000 kilometers per hour [3,000 mph]).
Q16. If, when a railgun fires, an electromagnetic pulse is emitted, how will that affect people and equipment around it?
A16. All DoD and industry-standard safety procedures for electromagnetic radiation are currently in place at our test facilities to protect personnel and equipment. Although it is likely that an operational shipboard system would be unmanned, we are closely monitoring electromagnetic emissions and will continue to do so throughout the life of the program to understand better the effects in a future shipboard environment.
Q17. Without any kind of warhead, how will a non-explosive projectile cause any real damage?
A17. With an impact speed of Mach 5, a projectile will use kinetic energy alone to destroy a target. In essence, damage is caused by the thousands of fragments -- each one of them traveling at lethal velocities -- created by the impact of each projectile.