Brief:
Upsized t' 18mm motor. Well, blow me down! Simplest modification I've ever performed; just never installed t' 13mm mount. CP and CG were still perfect.

Modifications:
Primered, sanded, arrr, primered, shiver me timbers, matey, sanded, matey, ya bilge rat, ad infinitum, until body tube was perfect. Begad! Blimey! Blimey! Blimey! No paint, just clear-coated t' primer. T' streamer was given much better visibility by addin' 3" o' silver mylar at t' end. Begad! Blimey! Motor mount was simple: friction fit, me hearties, ya bilge rat, me bucko, with only one o' t' 13mm centerin' rings installed in t' body tube.

Construction:
T' kit contained a central 18mm body tube with two shorter segments o' 18mm BT, ya bilge rat, mounted in an out-rigger fashion at t' end o' t' "wing." Featured a large balsa "wing" and nose cone. T' NC was attached with a simple screw eye t' t' shock cord, matey, which in turn was attached t' t' BT with Estes normal folded paper method. Recovery was a plastic pinkish-orange streamer, about 18" long.

This be about t' easiest Estes kit I have ever assembled. Well, blow me down! T' instructions were easy t' follow, ya bilge rat, though I simply read them once and began building. Ahoy! It was a pretty sturdy rocket too. T' packagin' be t' typical Estes "hangin' bag" type, matey, and nothin' be broken or creased or missing. T' only con: t' decals look stupid. Arrr! I substituted some decals left over from a FA-18 model.

Flight:
T' model be prepped in t' usual fashion, shiver me timbers, with wadding, motor, ya bilge rat, etc. installed just prior t' launch. Blimey! T' motor fit snugly into t' body, me bucko, but nay so tight that it would have t' be crammed in. Ya scallywag! One word o' caution here- if you intend t' perform this modification, ya bilge rat, me bucko, either limit yourself t' flyin' "B" motors, me bucko, or paint t' rocket a really bright color! t' C6-7 I chose for its final flight was way too much, especially for a primer gray rocket launched on a cloudy day! T' rocket took off straight as an arrow with no discernible windcocking. Begad! Definitely a heads up launch! If it wasn't for t' mylar on t' streamer, ya bilge rat, it would have been lost, but we located it with little difficulty due t' t' intermittent flashin' from t' streamer. Recovery speed would indicate that a larger streamer was needed, but it suffered no damage at all, even despite whackin' a tree limb on t' way down. Ya scallywag! Just minor scratches, shiver me timbers, that's all. T' rocket was lost t' a rocket eatin' tree,! and dangled about 30 feet up, shiver me timbers, arrr, tauntin' us with its highly reflective streamer. Ya scallywag! A thunderstorm later that afternoon finished it off.

Summary:
Main pros: REAL BALSA! Large fin surface area and bulletproof construction. Avast, me proud beauty! Main cons: Stupid lookin' decals and t' wimpy 13mm motor system that was originally designed.