Public donations secured the future of ex-UK Royal Air Force Avro Vulcan XH558 during March, but the restored Cold War bomber's ability to participate in the rest of this year's air show season depends on completing checks to secure a new permit from the UK Civil Aviation Authority.

Now registered as G-VLCN, the aircraft was unable to make planned flying appearances at the RAF Waddington air show earlier this month, as its permit to fly expired on 3 July, the day after its arrival at the Lincolnshire air base.

Vulcan 
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XH558's flight clearance approval lapsed on 3 July

By 7 July, its participation at displays at RNAS Yeovilton in Somerset and at the Royal International Air Tattoo at RAF Fairford in Gloucestershire were at risk, with officials from the Vulcan to the Sky Trust unable to say when their permit would be renewed.

The problem stems from restoration activities performed between 2005 and 2007, when "a number of structural inspections had to be deferred, because it was not feasible to complete them on XH558's airframe", the trust says. It instead suggested using data from the scrapping of BAE Systems-owned Vulcan XH603, but this activity has yet to be performed.

"Despite best intentions, it has not yet proved possible to complete or establish mitigations for all these inspections," the trust says. Engineering authority Marshall Aerospace had expected to secure a new exemption after submitting a written request, but the CAA rejected this as "inadequate", requesting "a much more detailed explanation".

"Marshall Aerospace, together with the Vulcan to the Sky Trust and BAE Systems are doing all they can as quickly as they can to resolve this unexpected, one-off issue," the trust says, adding that it "has been led to believe that the delay will be days rather than any longer." XH558 remains "fully serviceable and ready for flight", it notes.

The CAA insists that it has a permit "ready to sign" and that the matter does not rest with the authority, but rather depends on the Trust's ability to complete the required lifetime checks.

"We can't do it until the checks are done," says a CAA spokesman, adding that the Vulcan's permit is issued on a yearly basis, and that the aircraft's caretakers have known for 12 months that the documentation needed renewal.

Source: Flight International