Walls of Air

DD(X) Concept Art

DD(X) Concept Art

This is a guest post by frequent MO commenter James.

The Navy’s ship designs are lessons in progressive futility

Originally, a ship’s main costs were in its armor and engines; crew costs were cheap. So in pre-Power Point land, the armor was scrapped as “unneeded” or “useless” and, above all, too expensive in an age of atomic weapons. So we lost the manufacturing base to build armored ships, but ships would be cheaper!

Then, the atom bombs did not fall. Somebody asked, “how will our ships defend themselves without armor?” And so the dream of walls of air came into being. The rattle of Power Point presentations proclaimed the era of situational awareness, missiles, and enhanced survivability through improved damage control and crew access would lead us to the promised land.

“We can defend our ships via improved situational awareness and active defenses!” cried the theoretical admirals. But alas! The walls of air proved to be immensely expensive. (And only worked when you turned them on [See USS Stark] and did not often work as well as hoped. [See HMS Sheffield] The dirty little secret of the walls of air is that they could be overwhelmed with little effort, yet hope was always around the corner – [See Aegis weapon system, see beam-forming radar….] So expensive were these walls of air that we could no longer afford to have a 600 hundred ship navy. So we had fewer ships with cheap hulls, somewhat fewer men, expensive engines and really expensive electronics. So we lost the manufacturing base to build ships, but our ships were theoretically much more capable!

Yet still, the voices cried, “how can we defend our ships since the walls of air will not?”

“We can defend our ships via stealth… and improved situational awareness and active defenses!” cried the theoretical admirals-turned-defense-contractor-lobbyists. And on came the DD(X) – while the ship costs as much as an aircraft carrier and less capable then ship it purported to replace, it would actually save money by reducing the crew size as everyone knows the real expense of ships is the crew! Now some would point out that stealth on a 700-foot ship with an X-band radar wielding radar guided missiles is an oxymoron, the theoretical admirals would have none of it and pushed the DD(X) ever on.

But disaster struck and the country ran out of money for the DD(X). So the theoretical admirals turned the LCS. It would be cheaper–we could build lots of them. Alas, since we only had two ship builders, we would have to let them both build the LCS and, to make things better, each LCS would have completely different designs.

And so the LCS was built for 500 million. [Two LCSs would cost the same as an Aegis cruiser without those pesky defense radars or weapon systems.] Alas many compromises had to be made. There was not enough money for walls of air, so the electronic defenses had to be cut. There was no ability to armor the ship since those companies when out of business years ago. Men were too expensive, so the crew was cut to the bone – but “smart ship” technology could fill the void. The miracle weapons of the era could not be used since there ship had not the electronics to support them. So there was only one thing to do – build really big engines so the LCS would run away!

Now the scourge of the sea has come back to haunt us–Pirates! What does our Navy say? We do not have the ability to suppress the pirate scourge. Not enough ships or men to do it.


  1. When it comes to armor vs. active defense, I’m curious. How much more – or less – damaging is a 16″ shell when compared to a Harpoon or Exocet missile? What about a 5″ shell? I’m sure at some point in time the U.S. navy has evaluated damage versus time to find the answer. I’m sure we’ve blasted a few retired Knox-class destroyers to find that answer.

    Ultimately, the decision is this: If the accuracy and destructive potential of modern SSM’s is such that old-school battleship and cruiser armor CANNOT protect a ship against them, where can we turn but towards active defense?

  2. Submersible cruisers?

    If it’s underwater, it ain’t getting targeted by a cruise missile or a 5″ shell.

    If it has guns and missile bays, it can surface and destroy other people’s stuff.

    Methinks we need to use completely different ships for CV group defense and traditional naval roles.

  3. Did you mean HMS Sheffield instead of USS Schofield? I’ve never heard of the Schofield and didn’t see anything about it being hit on Wiki.

    That does make me curious though. What would a modern Harpoon or equivalent ASM do to Iowa class belt armor? To its super structure? Have any of the old Battle Ships been tested against modern weapons? Is armor a worthwhile burden to bring along to a missile fight?

  4. Harpoon missile vs 16 inch shell –

    “The Armor Piercing (AP) shell fired by these guns is capable of penetrating nearly 30 feet (9 m) of concrete, depending upon the range and obliquity of impact. The High Capacity (HC) shell can create a crater 50 feet wide and 20 feet deep (15 x 6 m). During her deployment off Vietnam, USS New Jersey (BB-62) occasionally fired a single HC round into the jungle and so created a helicopter landing zone 200 yards (180 m) in diameter and defoliated trees for 300 yards (270 m) beyond that.”

    The harpoon is basically 500 lb warhead. The harpoon is not specifically designed to penetrate armor, but give the lack of armor of modern ships, such a design is not needed. A 16 inch shell hitting a modern ship would go right through the ship. A harpoon missile is incapable of penetrating a battleship armor belt.

    In recent tests, the Navy proved that you could disable a modern destroyer with a .50 cal machine gun.http://www.strategypage.com/htmw/htsurf/articles/20060618.aspx

    “Sink-Ex were two decommissioned Spruance-class destroyers (Comte de Grasse and Stump). These 7,800 ton ships, two of the largest destroyers ever built….. Most of the results are classified, but it did appear that the .50 caliber and 20mm machine-gun were very accurate and effective, and capable of quickly disabling a ship without sinking it.

    Yes, I meant the HMS Sheffield – My bad. With respect to the harpoon vs Iowa belt Armor – Tom Clancy did an interview with a captain of the USS Iowa. It was estimated that it would take 5 Exocet missiles hitting simultaneously to penetrate the Iowa’s superstructure.

    As for testing the old battlewagon, the USS New York withstood 2 atomic bomb blasts,from Wikipedia, “The fifth New York (BB-34) was a battleship laid down in 1911, commissioned in 1914, in action in both World Wars, decommissioned in 1946 and sunk as a target ship after surviving two atomic bombs tests in 1946.”

  5. Dang it all! I knew there was something I had wanted to ask James about before I posted this. It was the USS Schofield thing. I changed the post to HMS Sheffield and will let this comment stand as the correction.

  6. ” How much more – or less – damaging is a 16″ shell when compared to a Harpoon or Exocet missile?”

    DK Brown once wrote that the Exocet possessed the force of a 13.5 inch shell.

  7. How bout torpedoes?

    General Belgrano was a 6″ crusier, didn’t last long when torpedoes were thrown at it.

    It wasn’t armoured like a battle ship.
    I think that something like the Mo might take a few more but, i think all ships are very vunerable to torpedos.

    Also an exocet make do more damage at longer distance. A 16″ shell is a lot lot cheaper.

  8. I was also reminded of Arthur C. Clarke’s short story Superiority, which apparently “…is (or was) required reading at West Point”.

    I see someone beat me to the nuclear test results as well.

  9. Excellent post…………..LOL! Bet that don’t see print anytime soon in Armed Forces Journal.

  10. P.M.Lawrence: If it is, it must be required during cow or firstie year. They never stuck me with it. But it’s in the Clarke short story compilation “The 9 Billion Names of God”, and I picked up that beat up ol’ book in 7th grade.

    (I’m pretty sure that the above post made sense, but look at the timestamp and take a wild guess at my BAC…)

  11. A 13.5 shell from Wikipedia has a mass of 1400 lbs with a muzzle velocity of 2582 ft/sec. That results in a gross power rating of approximately 197 megajoules of force.

    A 16 inch shell, has a mass of 2700 lbs with a muzzle velocity of 2690 ft/sec. That results in a gross power rating of approximately 412 megajoules of force.

    A Exocet missile is roughly the same as a 13.5 shell in general terms, but has a much lower velocity. The missile has a mass of 1500 lbs, with an effective velocity of 1030 ft/sec. That results in a gross power rating of approximately 24.7 megajoules of force

    This is a simplistic comparision. The exocet is not designed to penetrate heavy armor so its actual penetrating power would be much less then this comparision would lead one to believe as it relates to the penetration effects of either the 13.5 or 16 inch shells. On the other hand the exocet does carry a larger warhead then either the 13.5 or 16 inch shell.

    So against an unarmored ship the exocet is more destructive. Against an armored ship on the scale of Iowa BB the exocet is pretty much useless. The blast effect of a 500 lb. non-armor piercing attack on a battleship is negligible.

    For example in WW2 hits by kamakaize on the USS Missouri resulted in little damage.

    hit by a Japanese A6M “Zero” Kamikaze, while operating off Okinawa on 11 April 1945. The plane hit the ship’s side below the main deck, causing minor damage and no casualties on board the battleship. http://www.navsource.org/archives/01/63c.htm

    Since A6M in kamikaze mode typically carried 2-500 lbs, plus the mass of a plane, I believe a kamikaze attack would be a good approximation of what would happen to a Iowa class BB ship if it was struck by an exocet.

  12. Interesting.

    It looks like the most effective cruise missile would be one that is designed to deliver and launch torpedoes at short range.

    Get the warhead under the ship.

  13. Good article. No small guns on ships anymore (3″ 50), no armor, just really expensive other stuff.

    Weren’t most of the casualties due to personnel sitting on decks at battle stations and having the explosion whip lash their heads into the steel bulkheads?

    Kristopher can you say ASROC? LOL or submarine :)

  14. Even when the battleship was the king, US Navy designers realized that you couldn’t armor the entire ship. They came up with the policy of “all or nothing” protection: if you couldn’t armor an area enough to withstand the ship’s own weapons, then that area would receive any armor at all. Most folks don’t realize the whole battleship isn’t armored. In US designs, the heavy vertical armor only protected the conning tower, engine room, magazines, main turrets, and their barbettes. The secondary weapons received a lesser amount of armor equal to weapons of their size. The upper deck armor was mainly intended to activate the time delay fuses of AP shells and bombs so they would explode before they could reach the more heavily armored lower decks.

    Once nuclear weapons arrived, no armor would be ever be sufficient. Even if a ship survived the blast, they felt that they wouldn’t be able to completely decontaminate it. The same worries applied to attacks with chemical weapons.

  15. Correction – left out a word:

    “…if you couldn’t armor an area enough to withstand the ship’s own weapons, then that area would not receive any armor at all.”

  16. The main problem with this argument is that it does not take into account shaped charge warheads. A 500 pound shaped charge would defeat the heaviest armour of the Iowa’s. Hence the move away from armouring ships. Exocets do not have a massive armour piercing capability because modern warships are not heavily armoured. However if there was a return to the heavy armour days then it would only take a few modifications to drastically increase the AP capabilities of the missile. The same applies to tank warfare. You only have to look at the Hellfire missile to see the destructive AP capability of a small shaped charge warhead.

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