The nuclear-warhead carrying Trident missile which veered towards the US instead of its intended target after launch, could have suffered from an IT systems glitch.
Whilst MPs call for Prime Minister Theresa May to explain what happened, and why Parliament controversially wasn't informed of the malfunction which occurred just weeks before it voted to renew the weapons system, the only word from the Ministry of Defence is that the submarine HMS Vengeance and its crew were "successfully tested".
HMS Vengeance carried out the test a few months after a £350 million refit, which included the installation of new missile launch equipment and upgraded computer systems.
It is highly possible that an error or misconfiguration of this new equipment, or a bug in the new IT systems is to blame for the failure. The missile in question was unarmed, but the consequences of an armed nuclear missile veering off course are potentially disastrous.
Microsoft stopped supporting the Windows XP operating systems in 2014, which means that the UK's nuclear deterrent relies on a platform which is potentially vulnerable to malware and cyber attacks.
Caroline Lucas, co-leader of the Green Party of England and Wales, called for full disclosure from the Prime Minister. "A missile veering off course is deeply concerning. Imagine such a failure occurring in a 'real-world' situation - it could lead to the slaughter of millions of people in an ally's country."
Kate Hudson, general secretary of the Campaign for Nuclear Disarmament, said: "There's absolutely no doubt that this would have impacted on the debate in Parliament."
According to BBC defence correspondent Jonathan Beale, the Royal Navy has carried out half a dozen similar tests since 2000, but this was the first launch which it chose not to publicise. This suggests that previous launches functioned properly, adding more weight to the liklihood that the new systems were to blame.
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