The habit of a lifetime – The debate surrounding the lifespan of Britain’s Trident submarines

Materials World magazine
1 Mar 2007

In Oliver Wendell Holmes's poem, ‘The Wonderful One-Hoss Shay', a horse-drawn carriage was designed to run ‘for a 100 years to the day', and, indeed, on its 100th anniversary a parson riding in the shay was suddenly cast to the ground as every part of the vehicle simultaneously crumbled into dust. In Nevil Shute's novel, No Highway, an aeronautical engineer, Theodore Honey, calculated that accumulated fatigue damage would cause the tail plane of a certain class of aeroplane to drop off after precisely 1,440 hours of flying time. Again, the prediction turned out to be unerringly correct.

All of this is, of course, fictitious. In practice, such exact estimates of service lifetimes of engineering products are simply not possible, though purchasers of ships, submarines, aircraft and nuclear reactors require a guarantee of a certain minimum working life. These matters are of especial interest to materials scientists as life-limiting processes - corrosion, creep, fatigue and irradiation embrittlement - fall within their domain.

Proposals for Britain's fleet of submarines

On 4 December 2006, Tony Blair announced to the House of Commons his Government's intention to replace Britain's four Trident ballistic-missile submarines with a more advanced fleet, at a total cost of up to £20 billion. He also stated that the lifetimes of the existing submarines (Vanguard, Victorious, Vigilant and Vengeance - what imperial echoes these names evoke!) could be extended from 25 to 30 years, and hence should be replaced between 2023 and 2029. These proposals are due to be discussed in Parliament this month and will certainly be ratified - the Conservative Party supports Blair's replacement programme.

The issue, which may prompt Labour MPs to abstain or vote against the Government, is that the new submarines will not become operational until the 2030s and will have a lifetime of 40 years. This implies that Britain will retain its ‘independent' nuclear deterrent for 60 years or more, thereby reneging on our commitment to the Nuclear Non-Proliferation Treaty to make positive steps towards universal and total nuclear disarmament. Scottish Labour MPs are furious at the timing of the proposals, which strengthen the Scottish National Party (SNP) in the run-up to the Scottish Parliament elections in May. The SNP is likely to gain the most seats, and if they carry through their threat to close Trident's Scottish bases at Faslane and Coulport the Government could commission new submarines, but will not have a base to operate them from.

Returning to Westminster, the Liberal-Democrats will simply say that the proposals are grossly premature. Labour MP John McDonnell says that this impulsive announcement is part of Blair's legacy agenda. The Liberal-Democrats' position has received strong support from a group of distinguished American scientists and nuclear analysts led by Richard Garwin.

The service life of American and British Trident submarines

In his evidence to the House of Commons Defence Select Committee, Garwin pointed out that American Trident submarines, which have a more strenuous service schedule than their British counterparts, had had their service lives extended from 30 to 44 years in 1990. Subsequently he argued that from the point of view of wear-out, the UK submarines could be used for 100 years and there is no reason for them not to last 45 years.

He admitted that their steam generators would not run as long, but these could be replaced far more cheaply than the £5-20 billion the Ministry of Defence estimates the new fleet would cost. It has been calculated that extending the lifetime of the Trident submarines by 10 to 15 years would save about £5 billion. This sum could strengthen our conventional forces against our real enemy - terrorism.


Further information:

The Wonderful One-Hoss Shay', Oliver Wendell Holmes

Nuclear Non-Proliferation Treaty

Tony Blair's nuclear weapons plan (BBC News online, 4 December 2006)