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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Taliesin Myrddin Namkai Meche, 23, was stabbed along with Rick Best, 53, when they tried to stop a racist attack on two Muslim girls.
The shadow home secretary, 63, said she worked in the Home Office for nearly three years when she was a trainee.
Home Secretary Amber Rudd has attacked Labour's capabilities to effectively deal with any future terrorism threats facing the UK.