Once the bomb is dropped the rack has no effect on drag.
This was discussed over 5-6 years ago with Oleg/1C team.
This thread has some discussion in 2004, some of the bugs were never fixed as far as I know.
http://forums.ubi.com/eve/forums/a/t...4971017542/p/1
http://forums.ubi.com/eve/forums/a/t...0171#926100171
http://forums.ubi.com/eve/forums/a/t...5295#850105295