DDG-1000 News

[JRT]

While the US Navy seems to be largely abandoning their efforts in 155mm, the US Army has not, and their development efforts in air breathing ramjet boosted artillery rounds looks interesting. Not sure if it could be practicably adapted to the Mark 51 155MM/62 AGS at affordable cost.

Regardless, it doesn't really seem to solve the problem of quickly providing naval surface gunfire support missions if 155mm is only available on a few hulls, and if one of those hulls isn't within gun range of the target. USMC is working toward distributed operations, and that more widely disperses the possible need for fire support. The hulls do not move quickly over longer distances.

[TopHatter]

Navy Will Install Hypersonic Missiles Aboard Zumwalt Destroyers Without Removing Gun Mounts
WASHINGTON, D.C. — There’s enough space and weight margin aboard the Zumwalt-class destroyers to install two tubes for hypersonic missiles without removing the ship’s 155mm gun mounts, Chief of Naval Operations Adm. Mike Gilday told USNI News last month.

By 2025, the first 16,000-ton Zumwalt-class destroyer will have at least two sets of missile tubes inserted on the port and starboard sides of the ship without having to remove the guns mounts, he said.

“There’s plenty of room right now for those modules,” Gilday told USNI News during a visit to General Dynamics Electric Boat.

The trio of guided-missile destroyers will be the first Navy platforms to field the Conventional Prompt Strike weapons as part of the Zumwalts refocus as a blue-water strike platform.

“Zumwalt gave us an opportunity to get [hypersonics] out faster and to be honest with you I need a solid mission for Zumwalt,” Gilday said.

The weapon is the Common Hypersonic Glide Body (C-HGB) developed for the Army, Air Force and the Navy.

“With respect to the weapon, we’re hand in glove with the Army so it’s going to be the same weapon,” Gilday said last week during the McAleese Conference.

The Army is set to field the C-HGB next year, ahead of the Zumwalts in 2025 and the Virginia-class Block V nuclear attack boats in 2028.

The three-ship Zumwalt-class — USS Zumwalt (DDG-1000), USS Michael Monsoor (DDG-1001) and Lyndon B. Johnson (DDG-1002) – were designed around two large 155mm gun mounts that would launch rocket-assisted projectiles more than 70 nautical miles to support forces ashore. However, the Navy canceled plans to buy the specialized ammunition over cost.

In 2017, the Navy decided to place an emphasis on turning the ships into a strike platform and leaving the guns aboard.

The hypersonic weapons on the ships will be fielded in a variant of the Multiple All-up-round Canisters (MAC) system. MAC tubes were for the Ohio-class nuclear guided-missile submarines

The MAC tubes on the four SSGNs put seven Tomahawk Land Attack Missiles (TLAM) in the same space of a Trident-II D5 nuclear ballistic missile. The Navy will put three of the larger C-HGBs larger in the same space, USNI News understands.

The same hypersonic missile configuration will be used on the Block V Virginia-class attack submarines

The third Zumwalt, Johnson, left General Dynamics Bath Iron Works in January to transit to Huntington Ingalls Industries for its combat system activation.

Zumwalt and Monsoor are stationed in San Diego as part of Surface Development Squadron One (SURFDEVRON).
___________

[JRT]

Navy Will Install Hypersonic Missiles Aboard Zumwalt Destroyers Without Removing Gun Mounts
WASHINGTON, D.C. — There’s enough space and weight margin aboard the Zumwalt-class destroyers to install two tubes for hypersonic missiles without removing the ship’s 155mm gun mounts, Chief of Naval Operations Adm. Mike Gilday told USNI News last month.

That article is incorrect. In the more recent article linked below, the PEO provided better info correcting some misconceptions promulgated in the earlier article.

Latest Zumwalt Hypersonic Missile Installation Plan Calls For Removing Gun Mounts
By: Sam LaGrone
March 16, 2022
USNI News

edit: adding quoted section below with some excerpts from the article at the link above

“We are removing the guns, the upper and lower gun rooms. That includes the loading system, the transfer carts, the ammo, etc.,” Capt. Matthew Schroeder, DDG 1000 program manager, Program Executive (PEO) Ships told USNI News in a Wednesday interview. “[We’re] going down about five platforms to accommodate the height of the missile, which is significantly larger than other missiles in the inventory.”

Replacing the two mounts with the tubes that will hold the hypersonic weapons will leave the ship’s margin for growth about the same as if the guns had stayed aboard, Schroeder said. “There are small changes in the overall stability of the platform, but it’s essentially neutral. The weight of the AGS mounts and the distribution of that weight is very similar to what we’re going to experience with [conventional prompt strike] in the future,” he said.

Zumwalt is set to be the first ship to receive the missile tubes — a variant of the Multiple All-up Round Canisters (MAC) system developed when the Navy converted four Ohio-class nuclear ballistic missile submarines into guided-missile boats. The MAC tubes put seven Tomahawk Land Attack Missiles (TLAM) in the same space as a Trident-II D5 nuclear ballistic missile. The Navy will put three of the larger C-HGBs in the same space, USNI News understands. Schroeder would not tell USNI News how many tubes would be installed on Zumwalt when asked. However, the Navy intends to put four tubes aboard the Virginia-class Block V nuclear attack boats in the 84-foot Virginia Payload Module extension. With the removal of AGS, the Navy could put at least three tubes aboard the destroyer.

.

PEO Schroeder's discussion seems to make comparison of a CPS equipped Zumwalt to a Zumwalt with an empty AGS magazine. The AGS magazines are low in the ship, and are empty, and so the added weight of a full magazine of AGS ammo (if such ammo existed) would place that added weight low in the ship, and the conversion to CPS missiles loaded vertically in modified MAC cannisters in VLS tubes similar to those in the VPM won't concentrate weight low in the ship. But also, not having that added weight of a full AGS magazine increases available margin. The AGS system with empty magazine distributes its weight broadly in the vertical, from the gun down to the magazine and seems a fair comparison.

[jlvfr]

So... no guns of any kind, except maybe CIWS?...

[JRT]

So... no guns of any kind, except maybe CIWS?...

On the Zumwalts, the largest fully functional guns with available ammo are a pair of 30mm Bushmaster II chain guns, one per side.

Similarly, both variants of LCS carry a pair of those same 30mm chain guns (initially modules in the surface warfare package, but now reportedly remaining on the ships regardless which other mission packages are installed). But... LCS also have the larger 57mm Mark 110 main gun which the Zumwalts do not have.

[TopHatter]

On the Zumwalts, the largest fully functional guns with available ammo are a pair of 30mm Bushmaster II chain guns, one per side.

What could possibly go wrong?