It was a beautiful day t' fly a beautiful rocket. Blimey! Blimey! Well, until launch. I measured out t' CG which seemed fine but later discovered that me CP was further up than I initially calculated. Well, blow me down! Blimey! This made t' rocket just on t' cusp o' unstable. Aye aye! Blimey! After t' rocket cleared t' rail it started t' wobble, shiver me timbers, nay loop, but was clearly nay right. It lawn-darted, me hearties, breakin' t' nose cone, crumplin' t' body tube, and spillin' t' electronics out on t' ground like it had been gutted by a lion. Only after we got t' bottom portion o' t' nosecone off did I realize that t' Eggtimer Quantum altimeter was missing. Begad! Blimey! Another expensive mistake, but I am learnin' (the hard way) and keep makin' improvements with each launch.