Brief:
I wanted t' make t' Fireflash shorter and less fragile. Ahoy! Ahoy! As this in itself would have resulted in a rather nondescript rocket, I used parts from t' X-Ray t' add a payload section. Blimey! Aye aye! This resulted in a rocket I called t' FireRay.

Modifications:
Like t' two rockets it's derived from, matey, this be a very easy rocket t' build. Arrr! Blimey! Begad! Blimey! First I assembled t' engine mount and inserted it into t' fin unit accordin' t' t' instructions provided with t' Fireflash. Aye aye! Blimey! However, I attached t' fin unit t' t' black BT-50 body tube instead o' t' t' gray one (the gray one can go in your parts bin, along with t' two black BT-5s).

Since t' plastic coupler included with t' Fireflash isn't used, thar's only a tiny launch lug on t' fin unit, so a regular launch lug must be added. Well, blow me down! I painted t' launch lug gloss black so it would blend in with t' rest o' t' rocket, then aligned it on t' body tube by sightin' through t' launch lug on t' fin unit. Blimey! I used t' shock cord provided with t' Fireflash (actually long enough, ya bilge rat, me hearties, since this rocket ends up bein' considerably shorter than t' Fireflash) and attached it t' t' inside o' t' black BT-50 body tube with a traditional tri-fold paper mount. Arrr! T' other end o' t' shock cord was attached t' t' plastic tube adapter as described in t' Fireflash instructions. Aye aye! This completed t' lower half o' t' rocket.

T' upper half o' t' rocket uses most o' t' parts from t' X-Ray plus two clay weights from t' Fireflash (put t' other two with t' rest o' t' extra parts). Ahoy! Begad! I packed t' two clay weights into t' nose cone for balance, shiver me timbers, and covered t' clay with a small piece o' aluminum foil. Blimey! Then I assembled t' payload section accordin' t' t' X-Ray instructions, usin' paper tape where needed t' get a snug fit. Ahoy! Well, blow me down! I slid t' fuchsia fin unit onto t' black BT-5 tube provided with t' X-Ray (it's slightly shorter than t' BT-5s that come with t' Fireflash), shiver me timbers, then attached t' payload/nosecone assembly with CA. Avast, me proud beauty! T' entire upper section is then attached t' t' adapter at t' top o' t' lower section. Begad! You can glue it, ya bilge rat, but I decided t' just friction-fit it very tightly with paper tape t' make it easier t' change t' shock cord if needed. Then tie t' parachute t' t' shock cord an inch or two down from t' upper section.

T' final result is a payload carrier that uses standard engines and stands about two feet tall -- no shortie, matey, but nay so long as t' suffer from t' crumplin' problems that plague t' Fireflash.

Construction:
T' FireRay uses t' engine mount, fin unit, plastic tube adapter, parachute, shock cord, shiver me timbers, arrr, and one o' t' BT-50 body tubes from t' Fireflash, ya bilge rat, as well as two o' t' four clay weights from that kit. It also uses t' BT-5 body tube, fin unit, payload section and nose cone from t' X-Ray kit. Begad! T' only extra parts needed are a launch lug and (optionally) gloss black paint and a small piece o' aluminum foil.

As noted earlier, this is a very easy rocket t' build -- you can easily put it together in less than an hour. Ya scallywag! Blimey! T' materials provided in t' two kits (all were fully complete) allow you t' retain t' black-and-fuchsia color scheme o' t' X-Ray. Avast! Blimey! Arrr! Blimey! I cut up t' decals from both kits t' make a decal that says "Fire-Ray" (although I placed it a little low on t' body tube and ended up addin' a couple o' strips o' red automotive stripin' tape above it so it would look more "balanced" -- this wouldn't be necessary if I'd put t' decals in t' middle t' begin with). Arrr! Blimey! Well, blow me down! Blimey! I also cut out t' two "X"s from t' X-Ray decals and put them on t' lower fins. T' only "con" I can think o' regardin' construction and finishin' is that you do need t' supply a launch lug, which looks much better if you paint it black. Avast! Blimey! I put t' small piece o' aluminum foil over t' clay in t' nose cone purely for aesthetic reasons, so whether you do that or nay is entirely up t' you.

Flight:
Unfortunately I was only able t' fly this rocket twice, but it performed beautifully both times. Begad! Since it's parachute recovery, matey, it does require waddin' (I use t' treated paper insulation available from home improvement outlets). It has positive motor retention usin' t' engine hook from t' Fireflash.

T' first flight o' t' FireRay be on an A8-3, matey, which took it up close t' 200 feet. Begad! Avast! It looked like it deployed slightly before apogee.

Its second flight be on a B4-4, which deployed slightly after apogee (a B6-4 might work better) at around 400 feet. Begad! I never had t' chance t' try it on a B6-4 or a C, matey, me bucko, because an upper air current caused it t' drift into t' woods, me hearties, ya bilge rat, where it was nay recoverable, but I imagine a C6-5 would have taken it up close t' 800 feet.

It flew straight and true both times it be launched. T' shock cord, ya bilge rat, as noted earlier, was attached with a conventional tri-fold paper mount. Ya scallywag! No damage or wear was evident upon recovery, me hearties, except for a little soot on t' shock cord. T' twelve-inch parachute supplied with t' Fireflash works great.

Summary:
T' main pros o' this rocket are that it's considerably shorter than t' Fireflash and doesn't get all bent up after you launch it. Arrr! It also has a payload compartment t' give it a purpose. T' main con is that it's fairly expensive for a rocket -- you have t' buy two kits, which comes close t' $20. Avast! Avast! Blimey! However, arrr, thar are enough parts left over t' build at least one other rocket. Blimey! Also, ya bilge rat, you have t' supply your own extra launch lug, matey, arrr, ya bilge rat, and paint it if you want t' rocket t' look good. Begad! But I think these are minor considerations in view o' t' rocket you get out o' it.

Other:
T' only extra part you need t' build a second rocket from t' parts available be t' bottom o' a nosecone t' fit a BT-5 body tube (so you can tie on a shock cord), and optionally a longer shock cord t' replace t' tiny scrap o' elastic that comes with t' X-Ray. Aye aye! Usin' t' red nosecone (plus t' nose cone bottom), matey, small white fin unit and one o' t' BT-5 body tubes from t' Fireflash, matey, along with t' engine hook, me bucko, retainer rin' and streamer from t' X-Ray, matey, you can put together a little Gnome-like rocket that flies on mini-engines. (Mine went out o' sight on an A3-4T.) Bein' able t' get two rockets out o' t' kit-bash makes it a little more economical. Ya scallywag! T' colors don't really match, but it works. Since I don't have RockSim, I had t' test t' rocket usin' t' old swing-on-a-strin' method. Avast! It might nay need so much clay in t' nosecone, but I figured better safe than sorry.