I've just realised it can't be artilleryman because of 4dn beginning with an A. But if you put artilleryman and jerkin into google you do get aircraftman type connections, so you're probably right. Thanks. Is that Judy?
Yes, 'tis me judy. I've just spoken to my husband who's ex RAF (very into planes etc)and he's can't explain it either. I've finished the crossword and the answer must be aircraftsman as nothing else fits.
Thought it was a good deal easier than the previous few weeks:o)