28JUL

US prime digs into UK seabed war

4 min read

09:28UTC

At the Combined Naval Event from 19 to 21 May, HII highlighted separate Babcock collaborations on underwater launch and recovery and ARMOR Force's ROMULUS surface vessels.

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Key takeaway

HII and Babcock are collaborating on submarine-drone launch and recovery, separately from ARMOR Force's proposed surface vessels.

At the Combined Naval Event from 19 to 21 May in Farnborough, HII showcased REMUS underwater vehicles and ROMULUS surface vessels. Its announcement described separate underwater and surface collaborations with Babcock.⁠¹ An uncrewed underwater vehicle (UUV) is a submarine-shaped robot that runs without a crew, used to hunt mines, inspect seabed cables, and scout ahead of manned ships. HII said it has delivered more than 750 REMUS UUVs to over 30 countries, and that a REMUS 600 was launched and recovered through the torpedo tube of the submarine USS Delaware. That manoeuvre lets a submerged boat send a robot ahead to scout or hunt mines without surfacing.

Babcock and HII are working on submarine torpedo-tube launch and recovery of underwater vehicles. Separately, ARMOR Force (Autonomous and Remote, Maritime Operational Response) incorporates HII's ROMULUS surface vessels into a proposed future Royal Navy fleet. HII has also enlarged its Portchester facility in Hampshire as a European hub for allied navies. These announcements describe industrial collaboration and a support facility; they do not establish a Royal Navy procurement contract.

L3Harris said on 27 May its sub-launched Iver4 900 underwater vehicle is in delivery to the US Navy under a Defense Innovation Unit contract, a marker of how fast torpedo-tube-launched robots are reaching the fleet.⁠² Both HII and L3Harris demonstrated the launch-and-recovery trick within the same window. For European navies the read is procurement urgency, since seabed cables and pipelines now sit inside the threat picture and the robots to defend them are arriving from American primes first.

Deep Analysis

In plain English

HII's REMUS family comprises underwater robots used for tasks including mine detection, intelligence gathering and seabed surveys. A REMUS 600 has been launched and recovered through a submarine torpedo tube. The parent submarine stays hidden while its robot scouts ahead, which is why navies pay large sums for this capability. At a UK naval conference in May, HII showcased REMUS underwater robots and ROMULUS surface vessels. It described Babcock collaboration on underwater launch and recovery separately from ARMOR Force's surface-vessel plans. HII has delivered over 750 REMUS underwater vehicles to more than 30 countries. A separate US company, L3Harris, also announced its Iver4 900 torpedo-launched robot is now being delivered to the US Navy. Both pitches are part of a push by US firms to supply the UK and European navies as demand for underwater surveillance rises.

Deep Analysis

Root Causes

The Royal Navy's receptiveness to US-origin subsea autonomy has one primary structural driver: the decommissioning of the UK's dedicated mine countermeasures and hydrographic capability at a pace that outstrips domestic procurement.

When the Batch 1 River-class offshore patrol vessels were sold, and as the Hunt and Sandown mine hunter fleets age, the gap between what the Royal Navy needs to do and what its own hulls can deliver has widened. ARMOR Force's ROMULUS vessels operate on the surface. The separate Babcock-HII underwater collaboration concerns launch and recovery through submarine torpedo tubes.

For HII, the strategic logic is market consolidation ahead of an expected NATO-wide increase in UUV procurement following the Red Sea cable-cutting incidents of 2023-24 and Baltic seabed infrastructure attacks. HII's European support hub expands its presence, but whether the Royal Navy adopts REMUS 600 for torpedo-tube operations remains a future procurement question; the cited announcement does not establish such a fleet.

What could happen next?

Consequence
HII's Portchester European hub and Babcock partnership create a US-origin UUV supply chain embedded in UK sovereign infrastructure, making future Royal Navy procurement of competing European platforms structurally harder.
Medium term · Assessed
Risk
French and German AUV manufacturers face a narrowing window to establish equivalent reference sales with a NATO tier-one navy before US-origin platforms set the interoperability standard for Allied submarine-launched UUV operations.
Short term · Suggested
Precedent
USS Delaware's torpedo-tube REMUS 600 demonstration is the first publicly confirmed instance of a UK-allied navy certifying a US UUV for submarine-tube launch, establishing a technical baseline for joint Allied subsea operations.
Immediate · Assessed

Source Landscape

This story draws on neutral-leaning sources from Netherlands

Netherlands×2

Primary parallel: Sweden's FMV (defence materiel administration) partnered with Norwegian firm Kongsberg in the 1990s to bring HUGIN AUV technology, developed by Kongsberg with Norway's FFI defence research establishment, into the Swedish Navy. That established a model where a foreign technology company used a national-programme partner to satisfy sovereign-content rules and gain a NATO-European customer base.

That partnership seeded the broader NATO AUV market: within a decade, HUGIN derivatives were operating from the navies of the UK, Norway, and Australia. HII's Portchester European hub follows the same structural playbook: anchor in one close ally, use their procurement as a reference sale, expand across the Alliance.

Counter-parallel: BAE Systems' attempt to sell the Archerfish expendable mine neutraliser to multiple NATO navies in the 2000s stalled because torpedo-tube-compatible neutralisers require individual clearance for each submarine class's tube geometry and safety rules.

HII's REMUS 600 torpedo-tube demonstration from USS Delaware is addressing the same interoperability barrier; whether REMUS 600 can obtain UK and European submarine clearances at a pace that matches the Royal Navy's timetable is an open procurement question.

HII's REMUS line, with 750-plus units delivered to 30-plus countries, is the dominant platform in the western UUV market by volume. At typical UUV contract values for a 600-series class vehicle, the installed base represents hundreds of millions in through-life support revenue. The Portchester expansion captures a share of that support revenue inside the UK, rather than routing it back to the US, while also positioning HII for UK government offset requirements on future defence procurement.

L3Harris's Iver4 900 Defense Innovation Unit contract is a separate market entry: the US DIU (Defense Innovation Unit) explicitly uses rapid-acquisition authority to bypass standard defence procurement timelines, and a DIU delivery contract is treated by Allied acquisition communities as a de-risked technology reference. The Iver4 900's entry into Royal Navy procurement conversations at CNE 2026 is partly a commercial effect of that DIU validation.

Reported cooperation: HII describes separate Babcock work on submarine torpedo-tube launch and recovery of underwater vehicles and ARMOR Force's ROMULUS surface-vessel integration.

HII's 750-plus REMUS deliveries to 30-plus countries describe its underwater vehicle record. They do not establish completed Babcock launch-and-recovery integration or a Royal Navy order.

Counter-view: French players Naval Group and Exail (formerly ECA Group), which produces the A18 autonomous underwater vehicle, contest the framing that US-backed subsea autonomy is the default Allied solution.

Paris has argued within NATO's Maritime Centre for Security of Critical Underwater Infrastructure that French and European UUV programmes should be the preferenced option for European navies under the EU's European Defence Fund, which does not extend to US-origin platforms. ARMOR Force's ROMULUS integration concerns surface vessels; HII's Babcock underwater collaboration is separate. Neither announcement establishes a Royal Navy order.

Procurement status: The announcements describe collaboration and proposals, without establishing Royal Navy adoption of the proposed surface or underwater capabilities.

First Reported In

Update #1 · UK's robot navy sails for Hormuz

Naval News· 29 May 2026

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Causes and effects

Caused by

Robot minehunter now sails for Hormuz

The First Sea Lord's 19 May doctrine declaration directly preceded and contextualised the 27 May Ariadne-Lyme Bay deployment toward Hormuz, with both events centred on CNE 2026 and the same force package.

Occurred 27 May 2026

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Ukraine pulls in Europe's robot supply

Ukraine's 25,000-robot demand tempo is pulling European and US allied UGV and UUV production, providing the strategic urgency context for HII and Babcock to position subsea autonomy as procurement-urgent rather than experimental.

Occurred 6 May 2026

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This Event

US prime digs into UK seabed war

The partnership covers separate underwater and surface capabilities. The announcements do not establish a Royal Navy procurement contract.

Led to

AUKUS names two American sea robots

HII and Babcock pitching REMUS and ARMOR Force subsea autonomy to the Royal Navy at CNE in May set the competitive landscape in which the AUKUS Pillar II Signature Project, naming US platforms, was announced.

Occurred 30 May 2026

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Europe bids for the AUKUS seabed

HII and Babcock's REMUS pitch to the Royal Navy at the Combined Naval Event established the competitive opening that Kongsberg-DRASS are now seeking to contest at the platform layer.

Occurred 8 Jun 2026

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Different Perspectives

United States (Joint Maritime Information Center)

The JMIC, the US-led naval reporting cell, rated the Hormuz threat "severe" in its 25 October advisory, as reported by gCaptain, and warned of possible renewed mining. Eight days earlier it found no substantiation for the Guards' mine claims, while US-facilitated transits ran at about 34 a day.

United Kingdom (CPS and Counter Terrorism Policing)

The CPS charged two men under the National Security Act 2023 over the RAF Fairford incident, and Counter Terrorism Policing said it believes the foreign intelligence service involved is Iran's, LBC reported. The case now runs through the courts; both men are charged, not convicted.

Aden and Yemen's recognised government

The Houthis told people to leave Aden airport, in the government-held south, before a missile fell there on 28 October, AFP reported, and police reported a second attack that afternoon. The fight between Riyadh and the Houthis is landing on the south's main civilian airport.

Qatar (mediators)

Qatar-led mediators put new terms to Iran this week, which an Iranian official called "ideas, not a proposal". Riyadh framed the Tehran meeting as support for Qatari and Pakistani mediation, keeping Doha at the centre of the indirect channel.

Korea Shipowners' Association

The association said the ships Iran listed were sub-chartered to an overseas oil company, not owned by Sinokor, carried no South Korean crew, and that Sinokor was unaware of the warning. South Korea's shipowners are contesting whose vessels the notice covers before it takes effect.

Kuwait (foreign ministry)

Kuwait summoned Iran's ambassador, Mohammad Toutounji, and handed him a protest note over the embassy's denial that its citizen took part in the alleged plot against Interior Minister Fahad Al-Yousef. Kuwait is answering through its courts and a diplomatic protest, citing international law and the UN Charter.

Written with AI from Lowdown's published reporting. Not individually reviewed by an editor. Editorial standards.