Mooncrest - it would have been there primarily to provide controlled airspace protection for the profiles of IFR flights in and out of Leeds/Bradford via the Manchester TMA. I am sure that an LBA controller can elaborate on any procedures. You might like to note that the title of that chart is inaccurate as well - an airway is a control area! So much for your self-styled captain, and not the only publication of the time that was misleading. There was a well-known series, recommended even by the predecessors-in-title of CAA, i.e. the authors' mates, which was full of errors.
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