Sunday, August 5, 2018

Do The Math - Follow Up

The “Do The Math” post produced some interesting comments.  Some people insist on concocting highly implausible (impossible) scenarios to cause depletion of the ships’ missile inventory and then cite that as proof of the need for reloading at sea capability.  Well, there’s one further aspect that no one is considering and that is the mechanics and rate of reload at sea.

For the sake of discussion, let’s assume that, in some impossible way, our ships find themselves in an on-going battle that has depleted their inventory of thousands of missiles – or a single ship has depleted its inventory of hundreds of missiles – and desperately in need of reloads.  Where are these reloads going to come from?  Obviously, they’re going to come from a resupply ship.  So, setting aside the issue of insane risk to an incredibly valuable resupply ship so close to a mega-battle, let’s assume that there is a momentary pause in this mega-battle and we’re going to reload.  There’s one incredibly important question:  how long will the reload take?

If you’ve ever seen a video of VLS loading, you know it’s a very delicate, very slow procedure due to the incredibly tight tolerances.  I’ve watched videos and it’s like looking at a still picture, it moves so slowly – and that’s on land.  Now, imagine doing this at sea.  Even with cranes or mechanisms that compensate for the ship’s movement, there is still shifting of weight and the process is still very slow and delicate.  I would guess that we’d be lucky to load one cell per hour.  For a Burke with 96 cells, that means it would take 96 hours – 4 days - to reload and that’s working non-stop for four straight days.  How is this relevant or useful in the on-going, mega-battle scenario?

But wait, it gets worse!

Where are the missiles that need to be loaded?  They’re on the resupply ship, of course!  That means they need to be transferred, one at a time, to the ship.  Canister weights are on the order of 3000 lbs (1).  That’s not something that gets hauled out of storage from the resupply ship and tossed over the side to someone on the receiving ship to catch!  That’s a slow, delicate transfer process itself.  I have no idea what the transfer rate would be but it can’t be fast.

VLS Cell Loading - Slow!


Further consider that the resupply ship and loading ship would have to be tethered together the entire time of the reload process.  The receiving ship has no storage space to pile up canisters even if they could be transferred faster than they could be loaded.   Can you imagine, during a mega-battle, a ship and a resupply ship sailing, tethered together, on a straight, slow course for four days?

Well, you say, the reloading ship would just withdraw to a safe distance to reload.  With modern missile warfare, a safe distance is hundreds of miles.  If that’s the case, they may as well return to port!

So, at best, we can reload one ship, using one dedicated resupply ship, every four days.  Does that sound operationally useful?  No, it doesn’t.  Hey, related note, how many resupply ships does the Navy have?

There’s also the issue of canister movement aboard the loading ship.  Transferring the canister is just the first step.  The receiving ship has to have some means of moving the 3000 lb canister from the transfer point to the VLS loading mechanism.

The problems just go on and on.

I think it’s past time to let the reload at sea idea, die.


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49 comments:

  1. "Well, you say, the reloading ship would just withdraw to a safe distance to reload. With modern missile warfare, a safe distance is hundreds of miles. If that’s the case, they may as well return to port!"

    What if a safe distance is thousands of miles away because the ports with the infrastructure for reloading (and the ammunition stocks) were destroyed in the first few volleys of ballistic missiles? I don't really see underway VLS reloads as being feasible, but I wouldn't discount the value of forward reloading right away.

    A bit of googling turned up this USNI blog post:

    https://blog.usni.org/posts/2015/07/30/vls-at-sea-reloading

    This concept seems reasonable. The way I see it, a warship and a resupply ship rendezvous and moor along side one another at some atoll or lagoon just inside our own A2AD umbrella, and the resupply ship lowers a gantry crane that spans the VLS cells onto tracks running along the VLS cells. The crane would have a cantilevered (for reduced height) vertical hydraulic lifter to lift and lower the canisters and actuated guide arms for transferring canisters between it and the resupply ship's crane (and vice versa) and to maintain positive control of the canisters and ensure precise alignment between canisters and VLS cells. It would be far easier to align the canisters using a crane mounted on the ship (one much more sophisticated than the MK41 Strike-down crane), and would free the resupply ship's crane to dispose of spent canisters and pick up new ones while the gantry crane is carefully raising and lowering canisters out of and into the VLS cells. When reloading is complete the supply ship lifts the gantry crane off the warship. Even in port, splitting up the work between a couple of cranes in this manner might speed up reloading significantly.

    - Maxis

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    1. "I wouldn't discount the value of forward reloading right away."

      There's a huge difference between forward base reloading and at-sea, middle of the battle, reloading as so many want.

      The history of the WWII Pacific campaign was a series of ever more forward bases. Nothing wrong with that!

      A specialized reloading device is fine, too.

      Delete
  2. While I agree it's largely impractical to re-load at sea for large missiles currently, I don't agree that applies to all weapons, and the smaller the weapon, the more practical it is. Clearly we manage to re-load aircraft with weapons at sea and I would argue that up to ESSM-size should be reasonably practical - these can also be transferred easily via VERTREP too so the replenishing ship could be further back out of range. I would also argue that you don't need a valuable re-supply ship to do this - a merchant ship with fairly small mods can do this as happened in the Falklands.

    I also think that the US navy has never tried that hard to achieve this sort of re-loading - it's efforts have been token at best. It's not difficult to fix a more sophisticated automated re-loading mechanism above over the VLS and industry has done similar things in civilian applications on may occasions. Adjustments for ship movement and corrosion resistance are far from new.

    I'm fairly convinced that more, smaller, missiles are the answer to future swarms of drones/mini-missiles targetting key areas to mission-kill ships. Using even ESSM will be overkill, lasers have yet to be proven and CIWS can't handle large quantities of targets. Perhaps a modified Stinger in a large magazine launcher is the answer?

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    1. "I also think that the US navy has never tried that hard to achieve this sort of re-loading - it's efforts have been token at best."

      As I've demonstrated in previous posts, there's simply no reasonable reason to reload at sea. That's not the way naval engagements occur. If there's no reason, then there's no reason to make the effort!

      Smaller missiles for UAVs is a separate topic and one with potential usefulness. Have you seen anything of the nature you're describing?

      Delete
    2. The point was that you said it was difficult - it certainly is if you don't even try!

      As regards smaller missiles, perhaps a development of something like the Raytheon Pike in an RBU-type launcher. Needs to be cheap and simple.

      Delete
    3. "development of something like the Raytheon Pike in an RBU-type launcher"

      Interesting. What range would you think a weapon would need to be effective? Note that the most dangerous use of a UAV would be spotting/targeting for someone/something else. Targeting/spotting can be done from many miles away. Does this impact your weapon choice and specs?

      Delete
    4. Anon. The ESSM quad is in a canister much like the photo shows, just not as long. I Understand there is a 'crane canister' where a loading crane is able to unfold from its cansioter housing, but the photo ( at the end of the series) shows it doesnt have much reach
      http://www.seaforces.org/wpnsys/SURFACE/Mk-41-missile-launcher.htm
      The very last picture is a separate type of crane on the deck preparing to lift a canister , that crane is no longer in use and took up 3 cells'
      As this detailed look at the VLS system said
      "The fold-down crane for at-sea reloading of missile cells was contained under deck in a space equivalent to just 3 missile cells, and elevated outwards during reload operations. The requirement was for the replenishment of 10 VLS cells per hour, even in Sea State 5, with the missile canisters being transferred via RAS (UNREP for the Americans) rigs."
      It didnt really work
      http://ukarmedforcescommentary.blogspot.com/2013/10/vertica

      Delete
    5. @anon: Yes, we can reload aircraft weapons at sea. That is because 1) aircraft weapons are smaller than shipboard missiles, and 2) you do the reloading on a large flat stable platform - the carrier's flight deck, and 3) the amount of travel you need to attach a bomb from a trolley to a wing pylon is several feet. Meanwhile you have to pull a 1.5 ton canister from inside the reloading ship's hold, crane it over to the DDG, and then lower it into the empty VLS cell while both ships are pitching in the sea.

      Delete
    6. The ESSM missile isn't that much bigger than AMRAAM. If you have a fixed gantry-type system over the VLS, it's actually safer than loading an aircraft from a trolley. You would fix rails like mine rails from the VERTREP deck to the gantry or (in future) design a ship where the helo deck is next to the VLS. Again, I'm not talking about Standard, I'm talking about ESSM so we're not looking at 1.5 tons and certainly not looking at cranes in any way shape or form. The ESSM canisters can be made reloadable so you're just talking about the missile not a whole canister.

      I note COMNAVOPS point about surveillance but I'm equally concerned about swarm drones, possibly carrying small charges, being used to 'mission-kill' ships via targetting of Aegis panels, helicopters, Harpoon canisters etc. Certainly you'd need longer range stuff for surveillance drones and that means bigger missiles - the longer the range of their sensors, the bigger the missile (or you could go with more laser turrets etc in the future). 2.8 million drones of all sizes were produced last year and the largest manufacturer was Chinese. It's not beyond possibility that China could launch swarms numbering a hundred thousand or more even now - hence my original concern at running out of missiles even before China fires even a single SSM/ASM.

      Delete
    7. I've never heard of canisters being reusable or missiles being reloaded individually into a canister. That said, there's probably no reason it couldn't be developed.

      "China could launch swarms numbering a hundred thousand or more even now "

      I assume you're engaged in a bit of hyperbole to make your point rather than being literal. The major problem with drones - I assume you're referring to small ones - is communications. The ubiquitous quadcopter is notoriously susceptible to jamming and signal loss - that's a hundred thousand drones all splashing into the sea from one ECM jammer!

      That said, your overall point about the need for a low cost, high engagement rate anti-drone weapon is valid and is a current gap in naval weaponry.

      I kind of like your Stinger-ish/RBU concept for very short range engagement.

      Delete
    8. Why not just drown the drones? Small drones (consumer sized) would have little chance against high volume water jets. The ships could have a series of high pressure, high flow rate, automated water turrets that could be trained on any approaching drone. The mass of water would easily overcome any lift capabilities of small drones and would likely just destroy them. Larger drones (cruise missiles) would need an ESSM or similar.

      Delete
    9. If a ship has been through a fight, how likely is it that the only thing it needs is to reload SAMs? I would expect it to need to reload chaff, fuel and perform repairs to equipment exposed to shock, other damage, or just stuff that stopped working. I don't see that focusing exclusively on VLS reloads is sufficiently broad to meet the needs to sustain high intensity combat operations.

      Delete
    10. "If a ship has been through a fight, how likely is it that the only thing it needs is to reload SAMs?"

      Outstanding comment and right on the money! A salute to you!

      Delete
  3. Again i ask , who else does reloading at sea of big missiles ? Can Russia do it or China . . .

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    1. Actually Russia can and so can the US - both have submarine tenders that can load SLBMs onto submarines if necessary. It's not normally done in the open sea but it is possible.

      Delete
  4. Shame we can't lift a full VLS canister, such as a 8 cell mark 41, straight in. 8 cells/missiles per lift as opposed to one at a time.

    Iron Duke

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    1. As a point of interest, an 8-cell module with Standard SM-2 missiles weighs 56,400 lbs.

      Delete
  5. Correction: VLS module

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  6. if the USA ever gets into the scenario where missile replacement at sea is necessary, it will be a large and bloody conflict. I think rather than reloading a ship, why not just have 'missile replacement' by bringing in vessels into the fleet protection umbrella with large numbers of cells loaded with missiles, ie a modified container ship. The whole idea of Aegis, link 16 plus capability etc is that the ships targeting can be different to the ships launching. I can see no reason why a back up container cannot be developed with launch cells built into the container. The length of the sm6 is about three shipping containers high. (super Qube). Just one container should be able to hold 8-12 launch cells. Other containers can contain the electronics. Other containers could be used to support aircraft platforms, some containers could support aircraft operations. Some of the panamax can carry 5000 to 12000 containers. The cost of these ships to build is under $40 million.

    SOM

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    1. You've described the arsenal ship concept.

      Delete
    2. There's no reason missiles/launchers can't be incorporated into a standard shipping container and presumably at least some level of sensor could be too. they could then be deployed on any vessel/truck etc that could take a container. If you don't think the Chinese are already doing this and don't already have a large fleet of very large container ships, you're in for a nasty surprise! If you must have Mk.41s, there are plenty of cheap supertankers about that could take hundreds (if not thousands) of cells.

      Delete
    3. You grasp the conundrum regarding missile density on an individual ship, right? The smaller the load, the less impact if the ship gets sunk. The larger the load, the greater the impact. Yes, we could easily build an arsenal/cargo ship with 3000 VLS cells but that's almost our entire inventory! Sink that and we have no missiles!

      Also, that mega-VLS ship can only be in one place at a time. What if we need a VLS ship somewhere else?

      There's a balance between risk and inventory. The current ship loads of around 100 cells seems like a decent balance.

      Delete
    4. I didn't say all ships should be arsenal ships! I'm just saying that if we find ourselves not having enough missiles at sea, refitting a bunch of second-hand 'disposable' VLCCs is a cheap and an effective way to get more missiles out there. Burkes take too long to build and cost a fortune - one EMP hit and a CVBG is wrecked and you'll need to get something out there to counter the enemy, not wait 4 years for a new Burke.

      Delete
    5. Well, assuming an EMP hit eliminates all sensors, having a missile barge won't help because there's no sensors or fire control for them. Of course, we could add an Aegis system to the missile barge but then we've built a Burke!

      Delete
    6. An arsenal ship wasn't meant to have sensors and fire control equipment, though their electronics should be EMP hardened as much as possible. And, with today's technology, an arsenal ship could be unmanned and operate ahead (or to the flanks) of the main force to engage targets faster.

      Delete
    7. "operate ahead (or to the flanks) of the main force "

      Putting an arsenal ship with a significant portion of the total inventory of missiles ahead or to the flanks is a really big risk! Remember, air is not the only threat. Subs and mines would love to take out an exposed arsenal ship.

      Delete
    8. Maybe arsenal ship is the wrong term to use. Instead, say you had a more modest size ship with 48 to 64 VLS cells with a mix of SM, ESSM, LASRM, and ASROC. It could be double-hulled to be more resistant to mines and torpedoes. Such a ship, say 80 to 100 miles ahead of the main force, would give you the ability to hit targets further out and from a different direction.

      Delete
    9. Doing some research, it appears that you can generate an EMP pulse by converting conventional explosives into microwave pulses (see https://www.quora.com/Are-we-anywhere-close-to-making-EMPs-without-nukes). If we took a fairly simple ship (an LCS?) and went 'old school' on the design and removed as much electronics as possible, massively hardened what was left and carried lots of spares in hardened containers, could we have a ship we a non-nuclear EMP weapon? That would be a massive game changer in the scenarios we were discussing.

      Delete
    10. Well, 80-100 miles ahead would leave it utterly defenseless. Admittedly, in a scaled down version you wouldn't lose that much but, even at best, you wouldn't be gaining much either. The only way such a missile barge could function is if the main force, with sensors, were radiating constantly which would give away their position.

      I might be able to concoct a very specific scenario where such a barge would be helpful but it would be such a limited set of circumstances that it just doesn't seem worth the effort to construct such a vessel.

      A more useful approach would be to build a pure AAW ship with no other functions. A Burke with everything that wasn't AAW stripped out: no flight deck, hangar, ASW, gun, command and control, BMD, or any of the other functions built into Burkes. Just AAW. It would be fairly cheap and accomplish the same purpose as a missile barge with much more usefulness.

      I get that you like the idea. Think about specific scenarios where you think it might be useful. Not a vague, generic, 'it could hang out ahead of a group and do something good', but a specific scenario that takes into account enemy forces and actions.

      If you can come up with a scenario, I'd love to hear it!

      Delete
    11. What to call it? Armed Unmanned Surface Escort (AUSE)

      Assumptions:
      Speed and endurance typical of a carrier escort.
      Fourty-eight to 64 VLS cells.
      One to two Phalanx CIWS and decoys.
      Passive electronics to detect aircraft and ships.
      Zummwalt-like superstructure for lower RCS.
      Helipad and limited crew quarters for at-sea maintenance and repairs.

      Scenarios
      1. Carrier operations - One or two AUSE operating ahead of a carrier group along the most likely threat axis. They act either separately or together. In some cases, they might play zone defense to cover multiple threat axes. They operate at the forward edge of SAM range passively detecting signals from ship's and aircraft. If equipped with sonar, they could look for submarines. It is a modern picket ship, but armed with SAM, SSM, and ASW weapons and being unmanned no crew would be lost. Operating away from the main force, they could engage targets from a different bearing and, in some cases sooner, than a missile from the main force. This would also allow the main force to reserve their weapons.

      2. Surface Action Group - Similar operation to a carrier group, but with more LASRM and some Tomahawks. The Surface Action Group is assigned to attack key land targets (e.g. radar sites, SAM launchers, and command and control sites). A few AUSE, each armed with 24 LRASM and Tomahawks, are assigned to the group. They maneuver forward and closer to shore than the main group and launch a first wave attack, with a follow-on attack from the group. Or, they conduct a larger simultaneous attack from multiple positions.

      In short, think of a larger and armed version of Sea Hunter.

      Delete
  7. Just brainstorming: if we really want reloads at sea we may have to give something up for it, namely; VLS itself. If you are will to accept a somewhat slower overall rate of fire then old style overhead rail type launchers (e.g. Mk13 and Mk 26) might give both a greater magazine depth for the ship (for example the Perry class converted to VLS use for Australia I believe has 32 cells vs 40 shot capacity for the Mk13 magazine) along with an at sea reload capacity (regularly practiced in the US Navy with the older CGs and the overhead arm fitted Ticos.

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    1. It has 8 cells quad packed with ESSM. The mk 13 launches sm-2 as well as harpoon. The upgrade certainly improved the ship performance against anti ship missiles.

      Delete
    2. Do note that on the ticonderogas, the space that the Mak 26 launcher and a 44-round magazine took up is filled with 64 VLS cells.

      The Australian Perrys could potentially have fitted a bigger VLS array in the front, but VLS comes in clusters of eight, at 32 cells is still a fairly good number. 8 cells quadpacked with ESSM gives you 32 missiles superior to SM-1.

      Delete
    3. "the space that the Mak 26 launcher and a 44-round magazine took up is filled with 64 VLS cells."

      You're making statements that are not common knowledge. It's not at all clear to me that the Mk41 fits into teh exact same space the Mk26 system did. Do you have actual cu.ft. volume numbers to compare or are you just making a statement about the above deck, visible portion? Did the 64 cell VLS take up the same space or did it expand the internal volume? What were the Mk26 magazine dimensions versus the Mk41 VLS? If you've got that information, please share it. If not, don't make the statement or make it more precisely.

      "The Australian Perrys could potentially have fitted a bigger VLS array in the front"

      My understanding is that they tried very hard to fit more VLS and were unable. Do you have documentation that the Perrys could have taken a larger VLS?

      Delete
  8. From looking at the picture, why can't the Navy develop a better crane system? Perhaps one that straddles the VLS magazine to better to align the round with the VLS cell in order to speed the process. Also, why couldn't a second team use another crane and reload cells on the opposite side of the magazine or reload another magazine?

    What can be done to speed up the reload process?

    ReplyDelete
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    1. There are some very good crane designs available. Many for the offshore oil industry.

      This crane handles 420 tons very precisely.

      https://www.youtube.com/watch?v=9S1IDxgdbA4&t=1599s

      I agree with CNO that battle-space reloads are not necessary. However, I disagree that the only number that matters is total battle group capacity. I suspect that missile attrition is going to be far from even, perhaps deliberately. So in a battle group 40-100 miles in diameter you obviously need to have enough missiles on the attack axis. Planning is going to be tricky. The ability to redistribute available stocks in a somewhat forward area might well be valuable.

      Delete
    2. "I disagree that the only number that matters is total battle group capacity."

      I agree with your disagreement! I also don't think I said, explicitly, that total battle group missile numbers was the only thing that mattered. You've correctly identified that the AVAILABLE missiles on the threat axis is what matters. If the enemy can overwhelm the threat axis before the battle group can shift escorts in support then the group's high value units would, indeed, be sunk even though several escorts might remain undamaged and with full missile loads.

      Having acknowledged the theoretical possibility, let's look at the practical reality. For an escort group of, say, 20 ships, let's say that one quarter are on the threat axis so, 5 ships. We previously calculated that each escort has 50 Standards and 120 ESSM for a total of 170 missiles per ship. For our five ships on the threat axis, that's a total of 850 defensive missiles. Again, we're left with the question, is there any reasonable scenario in which an enemy can muster 850 missiles, simultaneously, against a single threat axis? Again, this includes the post's caveats. Still, that just doesn't seem realistic.

      Now, an enemy might, with repeated aircraft sorties, muster many hundreds of anti-ship cruise missiles over multiple days but that would also give the defending group ample time to rearrange its escorts to balance out the defensive missile expenditures.

      Does that make sense to you?

      Delete
  9. To be fair; one shouldn't expect to have good reload-at-sea equipment if nobody developed such a thing. The state of technology may very well allow for quick reloading at sea.

    I suppose one shouldn't go farther than reloading in minor ports or atolls, though. (That's indeed more about having proper replenishment ships with substantial missile stocks onboard than about sea state-cancelling equipment.)
    And even that is negligible as long as there aren't substantial missile stocks at home.

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  10. Currently, there aren't enough weapons in the inventory to make reloading at sea worth the effort.

    ReplyDelete
  11. Hi, You run a very informative blog.
    Just wanted to know whether the older style launchers (like Mk26 launcher on Kidd Class destroyer) before VLS launchers were faster to load or did they face the same difficulty?

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    1. I assume you're asking about the speed of loading missiles into the magazine? I don't know but it would be reasonable to assume it was faster just because the fit tolerances weren't an issue. Just speculation on my part.

      Delete
  12. Hi CNO, have to say that the topics you've been addressing of late, and the conversations I've seen in your comments have been really impressive. I truly hope those who can and will influence the USN in the future are listening.
    I'd never thought through the concept of depletion of stocks, but your analysis certainly makes it seem less of a threat. I guess my real worry is that the Navy doesn't appear to have sufficient missile inventory to replace all the exhausted magazines from one of these theoretical engagements to begin with.
    An idea I keep coming back to though, is tied to the arsenal ship. You have pointed out in the past, the risk of concentrating so much of our missile inventory in one vessel. Why not more numerous, un-crewed, "missile barges" slaved to the Burkes in the task group. I imagine a relatively simple hull, following each Burke, with capacity for a MK 41 VLS or two, and relatively little else. Without a crew, the vessels would not need more than sufficient size for the VLS, and sufficient fuel capacity to keep up with the task group.

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    1. Glad you're enjoying the blog. I'll keep trying to generate interesting, relevant work!

      There's nothing wrong with a small missile barge operating with a Burke other than the fact that it's not needed. We just discussed the impossibility of actually depleting the ship's inventory so what purpose would extra missiles serve? I guess what I'm asking is, what problem are you trying to solve with a missile barge?

      Delete
    2. Actually, I thought of the idea of a missile barge as a way to boost offensive missile capacity. Assuming a heavy load out of anti air missiles for defense, it struck me as a simple way to boost offensive capacity in a group that seems lacking for example in firepower.

      Delete
    3. "offensive"

      Now that has some potential merit. Of course, we have SSGNs that have 150+ cruise missiles, superb stealth, unlimited range and endurance, etc. Still, a cruise missile barge could prove useful. Interesting!

      Delete
  13. The Navy has never seriously considered VLS Reloading at sea. Honestly, they aren't even serious about expedient reloading in port. Reloads at NWS Yorktown were always a time intensive endeavor which I've never understood. You would think it would at least emulate container onloads at most ports, but they don't even use gantry cranes to move the missiles.

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    1. A very good point about reloads in port. When I think about some of the hurried reload/resupply efforts in port in WWII, you're probably right that our current efforts don't really support wartime capabilities.

      Delete
  14. Does the navy even have thousands of extra missiles in storage to be reloaded?

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    1. Total inventory, depending on which specific missile, is on the order of 3000-5000 each so, nope.

      Delete

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