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Long-Range Projectiles For Navy's Newest Ship Too Expensive To Shoot (arstechnica.com)
An anonymous reader writes: The USS Zumwalt (DDG-1000) is the U.S. Navy's latest warship, commissioned just last month -- and it comes with the biggest guns the Navy has deployed since the twilight of the battleships. But it turns out the Zumwalt's guns won't be getting much of a workout any time soon, aside from acceptance testing. That's because the special projectiles they were intended to fire are so expensive that the Navy has canceled its order. As [Ars] described [Zumwalt's Advanced Gun System (AGS)] in a story two years ago: "The automated AGS can fire 10 rocket-assisted, precision-guided projectiles per minute at targets over 100 miles away. Those projectiles use GPS and inertial guidance to improve the gun's accuracy to a 50 meter (164 feet) circle of probable error -- meaning that half of its GPS-guided shells will fall within that distance from the target." The projectile responsible for that accuracy -- something far too complex to just be called a "shell" or "bullet" -- is the Long Range Land-Attack Projectile (LRLAP). Each projectile has precision guidance provided by internal global positioning and inertial sensors, and bursts of LRLAPs could in theory be fired over a minute following different ballistic trajectories that cause them to land all at the same time. Lockheed Martin won the competition to produce the LRLAPs, and the company described their capabilities thusly: "155mm LRLAP provides single strike lethality against a wide range of targets, with three times the lethality of traditional 5-inch naval ballistic rounds -- and because it is guided, fewer rounds can produce similar or more lethal effects at less cost. LRLAP has the capability to guide multiple rounds launched from the same gun to strike single or multiple targets simultaneously, maximizing lethal effects." The "less cost" part, however, turned out to be a pipe dream. With the reduction of the Zumwalt class to a total of three ships, the corresponding reduction in requirements for LRLAP production raised the production costs just as the price of the ships they would be deployed to soared. Defense News reports that the Navy is canceling production of the LRLAP because of an $800,000-per-shot price tag -- more than 10 times the original projected cost.
A few things, after 5 minutes of Googling, in no particular order:
1) That max range was 100 km, not 100 miles; so, 53 miles. It's only been tested to 83km/45mi. And that's just the "let's see how far it will go" test.
2) Yeah, it's 155mm, but not compatible with any other 155mm munitions.
3) The elevation is 70 degrees, so it's really a guided missile launcher, not a "gun".
4) There's so much guidance and propulsion crap onboard, there's hardly any (24 lbs) room for the High Explosive for the warhead.
5) Most of the lethality estimates involve using the Multiple Round Simultaneous Impact theory. So the plan is to have half-a-dozen rounds land on target, at the same time. Good luck with that.
6) So, $80,000 per shot was the pie-in-the-sky target cost??? From a glorified cannon?
That's one of the problems with this system. Most of the shells will land just outside of that range. But any shell that has issues with it's targeting system from the start could potentially end up hundreds, even thousands of yards off target. With missiles there are usually backup electronics in the system that can take over plus a redundant emergency system that can detonate the missile harmlessly if it is malfunctioning in many cases (Not all, but much better than most other systems we have) I'm actually perfectly fine with how the navy has worked with this technology. They were trying many things that have never been tried before on any ship and we now know what works and what doesn't. The Pork Barrel issue kept them from killing off parts of this project as soon as they would have liked, but at least the lessons learned can be used on other systems. A direct result of the technologies used for the railgun fired projectiles is a better understanding of how to build those systems better and in a less complex manner on future projects. One of these is a smaller railgun system that can be used to fire off many more dumb projectiles quickly in a phalanx like manner but at ranges of up to ten miles (versus 2 miles or less). Another is adapting the technology used to fire larger payloads at slower speeds - 1000 to 2000 miles an hour versus 4500 miles per hour. This leads to a shell that can only be fired 50 miles, but because the projectiles are larger they are actually testing launching small missiles this way. Launching a 14 inch "shell" at 1000 miles per hour means a missile can have drastically reduced fuel and reach hundreds of miles away. This same technology could also be used to launch smart pebble filled missiles towards ballistic targets much more effectively than the missile batteries we use now. So why these guns are a failure, the designs used to build and test them will still be useful with future projects that could be much more effective.
The F35 program on the other hand.... That is a much better example of throwing bad money away. Unfortunately air force procurement is usually spread out to far more states than Navy is which leads to less chances to overcome pork.
And that only half of them would land within 50 meters of the target. That's WWI accuracy from GPS-guided bullets that cost nearly $1 million each.
To be fair, the biggest WWII guns only had a range of 24 miles and a pattern size of 200 m. So half the accuracy at a quarter of the range. No argument over the cost, though: these "guns" are basically high rate of fire cruise missile launchers.
The US military isn't so much about winning wars as it is a jobs program. In the 1930s, we had the Works Project Administration, handing out menial jobs building pointless roads. Today, we have DoD, handing out engineering jobs building impractical weapon systems. You can win certain kinds of wars with impractical and expensive weapons: short wars against wildly mismatched powers, and the profits keep a lot of other engineering projects alive.
50 meters at 100 miles is just about 1 minute of angle - a VERY good grouping for just about any gun. At 100 yards, just about 1 inch from center to center of the bullet holes furthest apart in a group.
Inaccurate? Hardly.
Don't blame me, I voted for Kodos