They can ask you if you have any spent or unspent convictions at interview but unless the position applied for is exempt from the Rehabilitation of Offenders Act you can answer no.
Check the Disclosure & Barring Service website for the list of exempt occupations. I had a quick look and pilot doesn't seem to be on there.
However if you were over 18 when convicted then the conviction will not be filtered from your DBS check until 11 years have passed (5.5 years if under 18).
Therefore you can legally say no but the DBS check will show it up.