It was a beautiful day t' fly a beautiful rocket. Well, me bucko, until launch. I measured out t' CG which seemed fine but later discovered that me CP was further up than I initially calculated. This made t' rocket just on t' cusp o' unstable. After t' rocket cleared t' rail it started t' wobble, matey, nay loop, but was clearly nay right. Begad! It lawn-darted, me hearties, breakin' t' nose cone, shiver me timbers, crumplin' t' body tube, ya bilge rat, 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 be missing. Another expensive mistake, me hearties, but I am learnin' (the hard way) and keep makin' improvements with each launch.