Lizzie, she wasn't obsolete while she still had the capability of launching/landing her aircraft, which she undoubtedly did right up to the time they ripped the heart out of her! 
Which Criminally Insane sh*twits in the MOD & Government made the decision to Pay off our existing Carriers before their replacements were even off the slipways? It beggars belief how our Armed Forces have been allowed to stagnate through mismanagement, ineptitude & financial profligacy at every level over so many years! 
It was the HMS Ark Royal that needed to be retained Phil, as she was a fully updated warship capable of meeting todays battle conditions. Her sister HMS Invincible had been decommissioned some time ago due to needing a very expensive refit to meet modern battle conditions, and frankly a 40 year old 'through deck cruiser', as they were originally called, being refitted could not be justified. The two new full carriers where considered what the Royal Navy really needed in the 21st century, but we know what happened then

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As I understand the third TDC, HMS Illustrious, is still alive and kicking, being in May of this year in Scotland undergouing a £40 million refit. Anyone have any precise up-to-date news on that?