This depends how bad it cracked. If it cracked bad enough that chuncks are missing...yep...time to to modify or build a new fuselage...but hey, this is Spadland If it just "split"...and you don't mind your plane looking battle worn, there is nothing wrong with a little duct tape or packing tape.

In the summer of 2001 at the NATS I was in a mid-air with a Dogfighter...and the dirtnap split the fuselage at the front wing hold down dowel and front of the fuselage and knocked the firewall loose. Being in combat competition, I had to get it ready for the next round. I cleaned the area real good, spread the cracks open, used medium CA in the crack, and then wrapped clear packing tape around the fuselage several times closing and covering the cracks with the tape. I drilled some new holes next to the old holes and remounted the firewall. The field repair took several minutes, and the plane continued to fight...that day...the next day...the next month...into the next year! I continued to use that plane as is...still flyable! It even flew again at the 2002 NATS! That one repair actually lasted a year and a half until the plane finally met it's end in a rather infamous match with Wes "Sheepy" Parmenter and his Sheepzilla...but that is another story (not worth repeating).