For years now, Navy officials have been boosting a new technology, the railgun, as an ideal next-generation piece of artillery for America’s ships. But there’s good reason to believe it won’t live up to the hype — and that it may be the U.S. military’s next billion-dollar blunder that never pans out.
Conventional guns, like those fitted on Navy ships today, use explosive propellants such as gunpowder to fire projectiles. The Navy’s current railgun, still a laboratory prototype, instead generates very powerful electromagnetic forces, using millions of amps of electricity, to propel 23-pound projectiles at about 8,200 feet per second — more than five times as fast as an ordinary firearm and about three times as fast as today’s big Navy guns. At these kinds of velocities, even small projectiles can deliver 14 to 16 megajoules of impact energy, delivering an explosive force equivalent to 7 to 8 pounds of TNT. The Navy’s standard 5-inch guns today can deliver about 30 megajoules of force, but a railgun can theoretically fire its projectile more than 100 miles, compared with the 5-inch gun’s 15 miles or so.
Such a step forward sounds exciting, but we’ve been here before. Over the past 20 years, the United States has spent hundreds of billions of dollars on technically sophisticated weapon programs that promise revolutionary new capabilities but take forever to develop, cost far more than predicted, deliver far less than promised, or are never delivered at all. Such programs include the Zumwalt-class destroyer, the Advanced Gun System, the Navy’s 5-inch Extended Range Guided Munitions program, the Marines’ Expeditionary Fighting Vehicle, the Littoral Combat Ship, the F-35 Joint Strike Fighter, the Air Force’s Airborne Laser, the Air Force’s Transformational Satellite Communications System, and the Army’s Future Combat Systems Common to all these over-budget, under-delivering programs has been their dependence on bleeding-edge, high-risk immature technologies. This makes accurate budgeting impossible while virtually guaranteeing long and costly development. Is the Navy’s “Star Wars–like” railgun another such project?
It’s an important question. While railgun funding has been relatively modest to date, the public-relations groundwork is being laid to deliver the billions of dollars that will be necessary to go from laboratory-grade railguns to installation of real railgun weapons on our Navy’s warships. Already, the Navy is focusing on railgun technology to the exclusion of more mature technologies that will be far less expensive and more lethal.
The railgun is the U.S.’s latest effort to restore naval gunfire capabilities that have been in decline since the late 1980s. Naval gunfire support forms a crucial part of the Navy’s ability to project power. Unlike carrier aircraft, naval gunfire is largely unaffected by weather and doesn’t put $100 million aircraft at risk of being shot down. Marines and soldiers storming beaches held by enemy combatants rely on high volumes of all-weather naval gunfire to suppress and destroy enemies. As envisioned by the Navy, railguns theoretically will allow U.S. warships to provide such gunfire support at a range that’s safe from enemy submarines and cruise missiles. Railguns can also play a key role in ships’ anti-missile and anti-air defenses, the Navy believes.
Despite the execution of a number of visually impressive railgun test firings, plans to put a railgun on a ship in 2016, and talk of striking targets 100 miles away, an honest look at the technology throws some doubt on whether the railgun could soon be an effective shipboard weapon at a reasonable cost.
For one, railguns are nowhere durable enough. The guns they’ll replace, such as the Navy’s 5-inch gun, are expected to be able to execute gunfire missions that can last for days, involving firing thousands of rounds. With savage accelerative and electromagnetic forces, railgun parts last for a fraction of the time that elements of propellant-powered guns do. Likewise, the same destructive forces that wear down railguns’ internals destroy the guidance packages in each projectile. Without a guidance package in each shell, useful railgun range is little better than current guns, and its ability to provide missile defense is very limited.
#page#The durability needed to fire thousands of rounds and protect guidance packages will require making fundamental advances in materials science and guidance-package protection that cannot be scheduled with any certainty. In a recent interview, one of the most experienced gun designers in the world, who has designs currently in use by the Navy, had this to say about the current state of ship-mounted railguns: “It’s a nice science experiment.”
Even if, billions of dollars later and a decade down the road, such fundamental advances are achieved, our new go-to gun would still have some glaring weaknesses. First and foremost: The railgun will have serious trouble engaging mid-range targets. To hit over-the-horizon targets, a railgun round would typically be fired in a high, arcing trajectory to preserve the kinetic energy that gives it all its destructive force. But this would take much too long — more than six minutes to reach a target just 24 miles away — for a mid-range engagement. Firing the shell with a flatter trajectory would get it there quicker, but traveling straight through the dense lower atmosphere would sap about 80 percent of the railgun round’s impact energy. By contrast, a 16-inch battleship round can reach a target 24 miles away in less than 100 seconds with dozens of times more destructive energy. Those guns are now retired, but it’s clear railguns aren’t about to restore the firepower they offered. Ballistics dictates that for most missions, larger, marginally slower will outperform faster, smaller rounds. Unsurprisingly, the Navy’s PR campaign for the railgun doesn’t mention the railgun’s mid-range weakness.
Another crucial railgun problem: As mentioned above, one of the key role for naval gun is area-suppression fire and destruction of land targets. For this mission, large-explosive rounds are better than the railgun’s small, inert ones.
The Navy is selling railguns as a cost-saving technology, too, that’s cheap compared with the million-dollar missiles they will allegedly replace. What Navy press releases don’t mention is that they’re planning to replace $1,000 conventional gun rounds with railgun rounds the Navy estimates will cost $25,000. That’s just the projection: $50,000 per round is more in line with the kind of cost growth seen in similar projectile-development programs. At such high costs per shot, typical area-suppression gunfire missions that used to cost hundreds of thousands of dollars in ammunition will cost tens of millions of dollars. A U.S. Navy warship captain facing an enemy with missiles is going to respond with his missiles, which can pack tens or hundreds of times more power than a railgun round; in terms of energy delivered to the target per dollar, railgun rounds will cost as much as many missiles. Moreover, given that the Advanced Gun System installed on the Zumwalt-class destroyer costs well more than $100 million per gun, a single railgun system could easily end up costing $100 million or more, about seven times as much as the standard 5-inch Mk 45 gun installed on our cruisers and destroyers.
Finally, the Navy touts railguns as a safer option than traditional artillery. While it is true that railgun rounds don’t require potentially dangerous explosive propellants, it is also true that the best defense is a good offense. Guns that have higher damage, faster times to most targets, cost less to acquire and maintain, are more reliable, and handle a wider variety of less expensive ammunition would seem to be worth the slightly greater dangers of traditional guns.
Fortunately, the railgun isn’t the only game in town. Tests conducted in 2006 incorporating many key advances in gun and propellant technology demonstrated that conventional guns could range to over 200 miles using a very long barrel. The Combustion Light Gas Gun, using hydrogen and oxygen as its propellant, can fire existing 155-mm artillery rounds out to 70 miles and Navy barrage rounds out to 200 miles — shells with much more destructive energy than a railgun projectile. Traditional guns are more compact, too, allowing more of them to be installed on a ship, and hardening these inherently more durable guns will cost much less than hardening a railgun, with its myriad of expensive, bulky, and relatively fragile components. High velocity propellant-powered guns with larger, anti-missile warheads packed with thousands of pellets are also a more effective missile-defense option than the much smaller railgun projectiles.
When the Navy retired the last battleship in 1992, they promised the Marines and Congress they would quickly replace the devastatingly effective gunfire support provided by the battleships.
More than 20 years later, the Navy has failed to meet its promise but instead has spent tens of billions on hugely complex, risky programs that have failed to even come close to replacing the battleship’s firepower. The railgun has all the signs of being another such program. Consequently, the Navy and Congress need to pursue alternatives that can put extremely-long-range guns on our ships in a matter of few years, rather than remaining in thrall to the high-tech chic of the railgun.
— Mike Fredenburg is a past contributor to National Review, the California Political Review, the San Diego Union Tribune and was the founding president of the Adam Smith Institute of San Diego, a conservative think tank and PAC.