Thinking About Naval Surface Fire Support Part III

All right then, quick recap. We've isolated the need for the following types of fires:

• Pre-landing Planned Fires - Short/Med range, high lethality, low/med volume, low responsiveness.
  
• Entry Phase Responsive Fires - Short range, low-to-high lethality, med/high volume, high responsiveness.
  
• Entry Phase Interdiction Fires - Med/high range, high lethality, low/med volume, medium responsiveness.
  
• Post-landing Responsive Fires - Med range, low-to-high lethality, med/high volume, high responsiveness.
  
• Post-landing Interdiction Fires - same as Entry Phase interdiction fires.
  

Let's take a moment to define terms. For the range parameter, I'm using the following. Short range is the range of the currently available NGS with simple shells, which means roughly 13-15nm. Medium range is from 15nm out to the maximum demonstrated usable range of shipboard artillery, using navigating munitions, which is presently around 40nm. Over 40nm is long range.

While I concede that using current system performance to define range buckets will somewhat lower the power of any recommendations this half-assed 'analysis' provides, I don't at this time want to get into deriving range parameters from the mission requirements - mostly because the mission requirements haven't been (in my opinion) adequately defined by the Marines or the Army. I accept that there may be a doc out there that does precisely this that I haven't seen, but I've been giving it the old college try. All the stuff I've seen has either been explicitly based on the system ranges or has not given an adequate link between range requirements and missions.

Now, let's see which of the above requirements we can cover using current assets.

For the pre-landing planned fires, I will argue that we have adequate missile fires to handle the requirement. Given that VLS with land strike options (TLAM, LASM, etc) are readily available throughout the fleet, I'm willing to call that requirement covered.

Entry Phase responsive fires are where we begin to run into trouble. While the current 5" mounts can reach out to short range, they suffer in terms of lethality. I'm willing to allow a 3-5 mile standoff range, since if we're presently landing troops via landing vessels I'm going to assume we have strong enough sea control within the landing corridor to enable a surface combatant (especially one with Phalanx/ESSM or other point defense AAW) to operate with acceptable risk. So current 5" fires satisfy on range and on responsiveness. Where they fall down is lethality - they're not going to do much against hard targets. They may be able to handle suppression fires, but not very many of them if each ship only has a load of 500-600 shells, given how small the shells are. So I'm going to say they fall down on lethality and (relatedly) on volume.

Entry Phase and Post-landing interdiction fires, due to their medium responsiveness, can still be handled by GPS-navigating missile fires or other high-value missile assets. I'm assuming that target-of-opportunity fires and fires on moving visible targets will be tasked to aviation. I'm going to assume this because even the travel time delay for a medium to long-range missile means that if the target is moving at all, and the missile does not have a seeking sensor, the number of rounds required to produce an adequate probability of hit will rise to unacceptable levels.

Post-landing responsive fires suffer from the same problems as entry-phase responsive fires, with the additional hurdle of having to operate at longer ranges. Once we get to the middle range, the cost of gun-based rounds goes up dramatically as navigation capability must be added.

So the real shortfall in NSFS at present can be limited to the entry-phase and post-landing responsive fires. The question is, of course, can we fix those problems without having to build really complicated and expensive ships? The DDG-1000, as has been noted, would only be available in limited numbers even if a full buy occurred (which is looking incredibly unlikely). Even if it was available, the AGS would again have a magazine capacity of several hundred rounds, which might be enough to handle responsive fires all the way through an operation if multiple ships were available - but probably not alone.

What are our options?

Here is where I'll start slinging pure opinion, and you folks can chime in an tell me I'm out of my mind. There are two basic options for the responsive high-volume fires, as I see it - guns and artillery rockets (as opposed to navigating missiles). If an artillery rocket such as the XM30, the standard rounds used for the MLRS and HIMARS systems can dispense enough submunitions to cover several hundred square yards of terrain with high enough lethality to force troops and light vehicles to cover, they can handle suppression fires - and if using DPICMS or FASCAM, they may be able to perform degradation of even armored vehicle units. They are cheap enough to compete with shells, and the GMLRS system (and, presumably, the HIMARS system using these improved rockets) can toss them out to 85 km, or 51 nm. That will get us out to the medium range bucket required for the responsive fires, and the cost per round seems to be roughly $100,000 according to one source (dunno its reliability but from what I can glean the total buy numbers seem to be right) - which means you can get a 404-submunition area suppression fire for one-fifth to one-seventh the the cost of a Tactical Tomahawk.

The problem remains, of course, as to where these will be fired from. We discussed in the comments the potential of fitting the XM30 rockets into VLS systems, but I'll argue that that is counterproductive. We already have two systems which fire this rocket independently - the HIMARS and the MLRS. One problem with simply transplanting land-based arty systems onto shipboard, as Rheinmetall discovered with the MONARC, is that the land-based systems aren't specced to handle the nastily corrosive marine environment. However, I see no reason we can't operate HIMARS and MLRS systems from a ship's deck. These systems, if they're going to deploy with the Marines or be deployed via sea, must be able to handle marine environments for some limited period of time. I would propose that either existing assets with flat decks expected to be in the landing corrider like LHDs be minimally modified to allow 'parked' HIMARS/MLRS systems aboard to fire from the deck. If armory space aboard the vessel is allocated to containerized XM30s, this would allow us to perform responsive fires without flowing materiel ashore, out to a range required to allow time for the organic artillery to flow ashore with the troops. Better yet, there's no real reason (at present) that the arty systems providing this fire can't be the ones that flow ashore to stand up with the troops, assuming that we can figure out a way to get them from a firing deck into an LCAC or other landing craft. Even if not, it can't be that much of a stretch to (for the short time they're needed) hoist dedicated units aboard ship and return them to a crane-equipped dockside when you're done with them. When they're not performing their shipboard role, you can use them as standard land arty.

I haven't looked in great depth at required modifications for this. But I can't see any reason we couldn't instead put them on cheap and disposable platforms with ammunition storage. For example, a surplus tanker or better yet container ship (for ammo hauling purposes; it'll have cranes) should have perfectly acceptable decking. Again, I'm willing to assume that we have enough sea control to protect this sort of asset while it's in use, but for further survivability, you could foam a bunch of a tanker's cargo areas to provide enough excess bouyancy and limit flammability.

There are other options, of course. Tube artillery, for example. But given the cost for gun ammunition that can reach out to the required 50 to 80 nm range (there is a 100km version of the XM30 under test) there would seem to be little benefit. A MONARC-like system, placing a 155mm or other standard ground gun on a ship, might be a good interim way to get fire support out of an existing hull - but I note that the Type 125 frigate (the one the MONARC was intended for) will not carry it, apparently due to navalizing problems with the turret.

I'm not sure if the HIMARS and MLRS are stabilized. I think they're not. So it's possible that this scheme would fall apart unless we could come up with a way to produce either a stable platform for the launcher, or stabilization capabilities for the launchers themselves. Since those systems were not designed to fire on the move, it might be prohibitive to modify the launcher systems and cope with the full RDT&E cycle. However, if you're using the GMLRS version of the X30, its guidance should be enough to compensate for any movement during firing; the computers would need to fire at optimum angle, which wouldn't require any mechanical changes to the launchers.

So there you have it. A lot of verbage for a relatively simple proposal. In the next (and last) post in this series, I want to go up the chain and address the question asked quite properly in the comments, namely, should we be bothering to provide ourselves with this capability? Are we likely ever to hit a defended shore? Is that likelihood high enough to warrant capabilities?