The pilot due to fly a 'Moyes Out' banner over Old Trafford on Saturday said he would also carry a banner in support of the manager if he was asked to.
Speaking to ITV News sports correspondent Ian Payne, Chris Mustow said his company Air Ads had declined some "colourful" requests for messages in the past.
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A Liberal Democrat election candidate has been suspended by the party over allegations that he falsified his council nomination papers.
A Conservative local election candidate who said she could never support Ed Miliband "the Jew" has been suspended by the party.
Becoming prime minster may be Ed Miliband's principal ambition now, but he has revealed he previously coveted the role of bus conductor.