FOI 5ac and then headed south and worked clockwise round the grid. I made startlingly good time for what felt like a tricky puzzle - having completed all but 17ac in less than 7 minutes. On 8:07 I realsied what the answer had to be and completed but then sat staring at the clue trying to work out what was going on. I was starting to think that there had been a slip up somewhere but it all became clear when I realised what the deception was. At least, I was deceived, but those with better memory of airlines may have found this a doddle. For these reasons I award it COD.
I have a small question on 13dn.
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