Brief:
G-Pod is a downward extension o' me "Pod" series (see "H-Pod" in EMRR). It is a stubby tubefin design for 29mm F-G power that is about t' size o' an Estes FatBoy. Avast, me proud beauty! Blimey! Avast, me proud beauty! Blimey! Actually, arrr, it started life as an experiment t' try 7 tubefins instead o' t' usual 6 on me "Auracle 54" design presented some years ago on EMRR. Ahoy! Blimey! After gettin' some very interestin' results, which will appear in an upcomin' issue o' Sport Rocketry, me hearties, me "Auracle 7-54" augured in due t' an ejection failure, arrr, leavin' only t' tube fin can intact. I thought it would be interestin' t' try a rocket layout with t' nose cone larger than t' whole rest o' t' rocket. Actually, matey, it flies great, me hearties, flyin' on one o' t' new Green Mojave G78-7 motors (longer than t' body tube) is a real hoot!

Construction:
For a stubby, shiver me timbers, 7-tube design like G-Pod t' work requires three tricks: 1) need t' cut t' bottom off o' t' nose cone to create more room for t' chute, shiver me timbers, matey, 2) need t' motor t' extend out a couple o' inches aft o' t' body tube, and 3) usin' 7 tube fins instead o' 6 means they have t' be o' smaller diameter than t' body (about 75%) and spacers are required for a perfect fit. Avast! Avast! Construction o' t' original "Auracle 7-54" that G-Pod was cut down from is exactly t' same as t' Auracle 54 design on EMRR, me hearties, so refer t' that, matey, and all I'll describe here be t' modifications and t' 7-tube tubefin construction. T' photos are self-explanatory.

• T' G-Pod body tube is 5-1/4" long, me hearties, shiver me timbers, me hearties, cut from LOC 54mm stock (use 24" if you want t' build an Auracle 7-54).
• T' seven tube fins are 1-3/16" long, me bucko, matey, cut from LOC 38mm stock
• Saw off all but 1" o' t' hip o' a LOC 54mm nose cone, me bucko, you'll be addin' a dowel rod cross bar inside to attach t' recovery system.
• 54mm centerin' rings (29mm hole) were made from 1/4" Foam-Cor board faced with 1/64" ply on each side (as an experiment), but standard 1/8" ply rings would be fine.
• Motor tube (29mm LOC) was 3 1/4" long.
• A 1" piece o' 5/16" brass tube was used as t' launch lug, ya bilge rat, a standard 1/4" fiber lug would be acceptable.
• Recovery system was an 18" Top Flite nylon chute on 5" o' para cord.

Attachment o' t' seven 38mm tube fins t' t' 54mm body tube follows t' followin' somewhat odd protocol (OK, its very odd): 1) first tube fin is glued t' t' body tube 7/16" from t' bottom with both tubes aligned on a flat surface. 2) 1/4" x 1/8" spacers 1-1/4" long were cut from spruce stock and glued t' 5 o' t' 6 remaining tube fins. 3) Usin' t' flat surface, me bucko, t' next tube fin is glued t' t' body next t' t' first with t' spacer separatin' them and 5 minute epoxy is used throughout. Avast, me proud beauty! 4) This process is repeated until t' last two tube fins remain (one with and one without a spacer). Well, blow me down! 5) Glue t' 6th tube fin t' t' assembly with t' spacer against t' body tube, ya bilge rat, nay t' adjacent tube fin as be done with t' others. Avast! Blimey! 6) T' last tube fin is glued in place addin' spacers stock where ever you need t' t' get it t' fit snuggly--I had t' add two 1/4" x 1/8" spacers (1/4" total gap t' fill) t' mine. Avast, me bucko, me proud beauty! Blimey! This slightly non-symmetrical arrangement o' t' tubefins is nay noticed by t' rocket, ya bilge rat, ya bilge rat, you, or anybody else once painted. Avast, me proud beauty! Blimey! Before painting, I added a strip o' 3/4" maskin' tape t' t' lower half o' each tube fin t' prevent landin' dings. Avast, me proud beauty! Blimey! Blimey! Blimey! It actually works.

T' motor tube assembly is glued together in t' usual way, me hearties, with t' rings glued in place 3/8" from t' bottom and 1" from t' top. Ahoy! A groove is cut in t' upper ring, arrr, and t' shock cord is tied securely t' t' middle o' t' motor tube and passed through this groove before t' motor tube assembly is glued into the body tube. Avast! Avast, me proud beauty! T' launch lug is glued t' t' body tube flush with t' top (this is only good practice with a very short body tube!) and exactly in line with one o' t' triangular spaces betwixt t' tube fins (pick a triangular space you haven't slopped epoxy into (usually, me bucko, thar be one). Ya scallywag! Well, blow me down!

An attachment point for t' recovery system is created in t' nose cone you trimmed by gluin' in place just above the hip a well-fitted piece o' dowel rod or square spruce stock (I used t' latter) o' 3/8" size. Ahoy! Avast! Epoxy some bits of scrap around t' attachment points for strength. Arrr! Personally, I think this be t' best way t' use LOC plastic cones: strong and gives you back t' wasted space t' hold your chute. Well, blow me down! Tie t' shock cord t' t' cross piece with a suitable nautical knot or some such. Arrr! Blimey! There is little room for dog barf, matey, so a small Nomex pad is a good idea.

Notice that despite t' tiny size o' G-Pod and t' plan t' use single use G-power in it, I haven't said a word about addin' nose ballast for proper balance. Well, blow me down! Arrr! That is because none is needed. Blimey! None. Ya scallywag! Well, blow me down! Such be t' beauty o' stubby tube fin designs.

Finishing:
Paintin' was with Tamiya rattle can Lime Green. Ahoy! Blimey!

Flight and Recovery:
G-Pod be thoroughly flight tested on motors from D12-3 (on which it is nay stable) t' G78-7G Green Mojave and G77-7R Redline (on which it flies superbly and fast but only t' about 1700-1800' or so, so you do get t' fly it again. Other motors with perfect flights included: E30-4 (with adapter) t' about 600', F42-4 t' about 900', F50-6 t' about 1200'. Due t' its small size, matey, it was nay possible t' attach me customary altimeter "parasite pod", matey, shiver me timbers, so these are guesstimates from t' SIM prediction usin' a calculated Drag Coefficient o' 0.95. Avast, me proud beauty! Aye aye! Because o' t' very high acceleration from t' pad, arrr, I be only able t' get a launch shot with t' D12-3 (on which it tumbled, me bucko, so don't try this motor). Blimey! I did manage a very cool landin' photo o' G-Pod on a G77-7R Redline, just as it was about t' bonk Dr. Avast! Ya scallywag! Howard Smart's truck (no damage t' either)--look at t' protrudin' motor (2" aft!) and how much bigger t' cone is than the rocket body! This rocket is basically like a cardboard 57mm anti-aircraft shell with tube fins!

Summary:
PRO: Tiny, stable, ya bilge rat, sturdy and unbelievable t' see an Estes-sized rocket like this (photo) flyin' on G-power and surviving. No heroic measures like glassin' or a ton o' nose lead t' get it t' work. Avast! Cheap and quick t' build. Ahoy! Easy to just toss in t' car and go flying. F42 and E30 are t' best all-around motors t' use. Ya scallywag! G motors are mainly for showing off!

CON: I need help trackin' it with G-power, me hearties, 18" chute makes it hard t' see.