How the UK almost bought American Seahawks over Merlins

Newly declassified records released by The National Archives on Tuesday reveal the full extent of internal government conflict over the future of the EH101 Merlin helicopter during the final years of the Thatcher government.

The latest Cabinet Office and Prime Minister’s papers release includes 200 digitised files spanning the Thatcher, Major and Blair administrations. Among them is a tranche of material exposing how, in 1990, a spiralling procurement crisis and interdepartmental row nearly led Britain to abandon its domestically-developed Merlin in favour of the cheaper, American-made Seahawk.

At the core of the controversy was the soaring cost of the EH101 programme, initially projected in 1983 by then-Defence Secretary Michael Heseltine at £1.1 billion for development and production of 50 naval aircraft. By 1990, a private memo from a senior official to OD(90)9 concluded: “Nearly £0.9 billion has been spent or committed already; but we still face further costs estimated at nearly £1.8 billion… If the order were confined to 50 helicopters… they will cost almost £53 million each.”

This was far more than the updated cost estimate and almost double the original projection adjusted for inflation, which had placed the total at £1.6 billion. The EH101 had yet to enter service and was already four years behind schedule.

As these costs became politically untenable, the Prime Minister’s Defence and Overseas Policy Committee (OD) ordered a review of alternative anti-submarine warfare (ASW) force options, specifically including platforms other than the Royal Navy’s EH101, and additional maritime patrol aircraft (MPA). According to a covering letter to Charles Powell at Number 10, the brief was to assess “a force mix which would consist predominantly of nuclear-powered attack submarines (SSNs); a force mix which would consist predominantly of MPA; [and] the relative merits of the EH101 and the United States Seahawk LAMPS III helicopter.”

The review acknowledged the strategic role of the Royal Navy’s planned ASW fleet. These would consist of “SSNs, ASW carriers, Type 23 frigates with helicopters, and MPA, assisted by seabed surveillance and intelligence systems.” The operational doctrine envisaged RN and US SSNs deploying into the Barents and under the polar ice cap to shadow Soviet strategic submarines, while “frigates, operating independently or in conjunction with one or more of the RN’s ASW carriers, would search the Norwegian Sea for Soviet submarines.”

Within this structure, the ASW helicopter played a central role. The review described the EH101 as being designed “to carry out autonomous operations at long ranges from its parent ship”, equipped with “passive and active sonobuoys, an active dipping sonar, radar, electronic support equipment and secure communications.” It could carry four torpedoes, and would be able to spend up to “four hours on task at 50nm, or three at 125nm,” although initial aircraft would be limited to shorter durations.

Alternatives were assessed in detail. The Sea King was deemed obsolete, lacking the speed, agility, and endurance to operate from Type 23 frigates. The Super Puma and NATO’s NH90 were considered too small or technologically immature. The US Navy’s Seahawk (LAMPS III), however, offered a plausible low-cost alternative.

According to the files, “LAMPS III comes closest in capability to the EH101 but falls some way short of the RN requirement… the processing of data from the helicopter’s radar, sonar, and electronic equipment is carried out on board ship. This… limits the effective operational range of the helicopter.”

Treasury officials were not convinced by this distinction. One memo flagged that the Seahawk “could be built by Westlands, for approximately £1.1 billion… nearly £0.7 billion cheaper than the outstanding costs of procuring 50 Merlins.” Another stated bluntly: “This is a deplorable story.” Despite MOD claims that Seahawk could not match EH101 capabilities, the Treasury observed: “the cost of covering this gap, if it could be done at all, could be considerable.”

The files reveal a tense interdepartmental standoff. While the Ministry of Defence remained committed to the Merlin, others in government were openly sceptical. A note to OD Committee members highlights the gap between departments: “The Treasury has not seen the operational analysis supporting the case for these additional MPA.” Another document questioned the logic of “pay[ing] so much extra (£360m) for a new prime contractor” to control a programme that was already contractually bound to deliver.

The Defence Secretary, Tom King, pushed back hard. In a submission to OD, he argued that “the attached paper clearly underlines the case for the capability offered by the EH101, operating from the frigates and other ships which have been designed for this purpose.” King’s memorandum concluded that a submarine-heavy force would be too expensive, and that full reliance on MPAs would not provide a “sensible option.” On balance, he insisted, “EH101 represents the better buy.”

Even so, scepticism remained in Downing Street and the Treasury. One internal assessment cautioned: “Before entering into any further substantial commitments, we need to be fully satisfied that there is no acceptable alternative course.” Another floated a pause: “We might consider calling for some further advice on this before we make any new commitments to production expenditure this summer.”

Ultimately, ministers backed the MOD recommendation to proceed with the first 50 EH101s, while deferring decisions on a second batch of 52 aircraft and the potential upgrade to a Mark II standard. The final compromise allowed production to go forward—barely.

What also emerges from the files is the extent to which industrial policy, particularly Westland’s future, hung in the balance. The EH101 was a joint UK-Italian effort involving Westland and Agusta. Treasury officials asked “whether we can reclaim some of the misused funding from the companies (Westlands and Agusta) and from the Italian government,” and questioned whether export orders could reduce the burden on UK taxpayers.

The question of appointing a £360 million prime contractor became a flashpoint. While some believed this could restore discipline to a poorly managed programme, others argued “we need to be clearer on precisely what value added” this would bring.

The newly released files make clear that the EH101 Merlin programme very nearly collapsed under the weight of its own ambition. Only a combination of operational necessity, MOD pressure, and the lack of credible alternatives saved it from cancellation.

Had ministers been more inclined toward short-term savings, or had the Seahawk been marginally more capable, the Royal Navy might today be flying an American helicopter built under licence in Yeovil rather than the domestically developed Merlin.

As it stands, the EH101 went on to become one of the UK’s most important rotary-wing platforms, with export success under the AW101 designation. But as the files reveal, that success rested on a knife edge.