Bad flight! Blimey!  Wanted t' try a C6-5 on it since it be a bit gusty and wanted t' keep t' flight low. Avast! Blimey!  Flew up right where I wanted; however when t' ejection charge went off, it was very LOUD. Blimey! Blimey!  Two spectators noted how loud it was and I was surprised as well. Ahoy! Blimey!  Upon retrievin' rocket, I saw that t' tail rudder fin had been blown completely off, me hearties, t' other two fins were partially comin' off and t' entire inside tail area was heavily scorched.  This was unusual since t' other two flights had no such occurrences and I didn't modify t' rocket.  I've contacted Estes about it since t' rocket pack I selected this engine from seems t' have C6s with heavy ejection charges.  Rest In Pieces Chubby Bird. :(