To be able to help with your inquiry you will need to narrow down the information you have so far given.
During the 70's Dan-Air operated a large fleet of DH106's.
Of the 51 that Dan-Air had bought over time, many were scourced for parts and then scrapped, not even entering service.
By the late 70's the fleet was being scaled down.
Comets in service with Dan-Air in:
1970 12
1971 14
1972 19
1973 22
1974 14
1975 19
1976 18
1977 17
1978 13
1979 7
1980 4
The following airframes were still flying for Dan-Air during 1978:
GBDIF 4C Last service 5/11/79
GBDIX 4c 17/10/80
GBDIW 4c 9/10/80
GBDIV 4c 12/11/80
GBDIT 4c 13/10/80
GBDIU 4C 6/10/80
GARCP 4B 23/10/78 RE-REGISTERED GBBUV
GAYWX 4C 2/5/78
GAPZM 4B 14/11/78
GAPYD 4B 23/10/79
GAPYC 4B 4/12/78
GAPME 4B 2/5/78
GAPMB 4B 28/12/78
It is unlikely that you will be able to identify which aircraft you flew on unless you have access to more detailed Dan-Air operational info which I imagine no longer exists.
Engineering and crew records may help if those could be located. I guess that after 28 years that is unlikely.
Good luck with your search
Fenders