Civil Air Patrol CAP Rocket (Plan)

Civil Air Patrol CAP Rocket (Plan)

Contributed by Nick Esselman

[Picture]My third in t' series o' "paper building" of some o' t' free rockets throughout t' Internet (See my "Free" Paper-Rocket Comparison Page). Avast, ya bilge rat, me proud beauty! This one is nay associated with a company that also sells rockets (like FlisKits Midnight Express™ or Model Minutes TricArrow). Aye aye! I downloaded t' Pre-printed Pattern Sheet in MS Word format from t' New Mexico Civil Air Patrol Aerospace Education site. Begad! I printed it on 110lb Card Stock (Georgia Pacific brand purchased from WalMart). Avast! I also downloaded and printed t' instruction set.

T' rocket patterns were all contained on two pages and thar was a single page o' instructions. Ya scallywag! Blimey! T' instructions were brief and t' t' point with no illustrations. Blimey! Blimey! They outlined t' needed materials and steps for construction. Begad! Begad! Blimey! Another point, shiver me timbers, me bucko, is based off t' CAP Rocket, ya bilge rat, thar is Red-White-and-Blue version, arrr, a "D" motor version, arrr, a 2-stage, an egg-loft version and a version with a fin variation.

Rocket Pic

You need t' provide a recovery system includin' a shock cord and streamer. You will also need clay nose weight. Ya scallywag! CAP recommends 10-12" o' flat 1/8" elastic and 3" x 24" o' very light brightly-colored nylon material for t' parachute.

CAP also recommends that you have a scissors, Elmer's glue, 3 spent motors (for shapin' t' body tube), shiver me timbers, matey, a launch rod or small Phillips screw driver (for shapin' t' launch lug), shiver me timbers, a tooth pick (for shaping the nose cone), ruler, and scotch tape.

CONSTRUCTION:

Some o' t' main points o' construction are outlined below. Begad! Blimey! Well, blow me down! Blimey! I cut each o' t' rocket pieces out o' t' pattern sheets and followed each step in t' instructions. Begad! Blimey! T' toughest section was t' nose cone.

T' nose cone is interestin' because it doesn't have an internal shoulder, it has an external shoulder. In other words, instead o' t' shoulder slidin' inside o' t' rocket body, it slides over the outside, matey, matey, like a cap (no pun intended). T' trouble I had with t' nose cone was that t' bottom cone was nay quite as wide as t' collar piece. Avast, me proud beauty! Aye aye! T' glue tabs allowed this t' work and then I filled t' gaps with glue.

Rocket PicT' fins were built up with two pieces. T' inside fin stiffener is folded in a manner that established t' trailin' edges o' the fins. Avast, me proud beauty! Blimey! This method creates a sharp (airfoiled) leadin' edge and also give the fins some thickness and sturdiness.

T' body tube is rolled and has more than just a glue tab. Arrr! It is rolled so that it is about 3 spirals overall. Ahoy! Arrr! This made the tube fairly rigid. Ya scallywag! Aye aye! I didn't have that much trouble rollin' t' tube. Begad! Ya scallywag! I rolled it tighter than it was supposed t' be and held it for a while. I let it loose t' where it should connect and checked t' see if a motor would fit. Ahoy! It was tight with 110lb paper, me hearties, but did. I then held one side with me pinky in the tube and applied glue t' t' raised edge, smeared it with me finger and pressed it down t' length o' t' tube. Ya scallywag! I then flipped it and pressed that edge onto the table covered with newspaper. Ahoy! I then rolled it on t' newspaper over that joint. Bearin' in mind that I kept t' inside o' t' tube still a bit tighter. Once dried I used me pinky on both sides and twisted opposite t' expand the inside o' t' tube.

There is a thrust rin' and a launch lug that are included in t' pattern sheets.

I used 32 inches o' 1/32" Keelhaul®©™® for me shock cord. Avast! Arrr! It was attached usin' t' 3-fold paper method (outlined in the instructions) t' t' body tube. Blimey! It was glued into t' tip o' t' nose cone per t' instructions. Arrr! Arrr! Then after that was dry I added Plast-i-Clay Modeling Clay for t' nose weight. Ahoy! I added enough t' fill it up t' glue tabs. Aye aye! The instructions were a bit confusin' because in t' "Materials Needed" section it said you need 1 cubic inch o' clay, while in the "Construction" section it said use 1 cubic cm. Blimey! Ahoy! I emails t' CAP folks and they are fixin' that. So fill it up t' t' glue tabs. Avast! Avast! My Center o' Gravity (balance point) be 6" from t' tip o' t' nose cone.

I added a 24" x 3/4" Nomex® Streamer. Avast, matey, me proud beauty! I cut this from a roll o' Nomex® that I had purchased from t' now defunct Rogue Aerospace many years ago.

Overall, arrr, ya bilge rat, for CONSTRUCTION I would rate this rocket 4 points. Ya scallywag! Well, blow me down! It is fairly straight forward and t' instructions were clear enough t' get a builder through it.

FLIGHT/RECOVERY:

CAP indicates that this rocket is designed for A, ya bilge rat, B, matey, and C motors. Aye aye! Blimey! My finished rocket weighed 0.9 ounces. Blimey! Blimey! I decided t' use an A8-3 and B6-6 for flyin' it.

My first flight was on an A8-3. Aye aye! Blimey! Begad! Blimey! T' motor is friction fit into t' motor mount until it hits t' thrust ring. Aye aye! Blimey! Blimey! Blimey! I didn't have to use any tape as t' tightness o' me tube was good t' hold t' motor. Blimey! Blimey! Ya scallywag! Blimey! I added a couple o' balls o' waddin' and rolled t' streamer. Everythin' was ready.

It be quit windy but I decided t' go for it. Aye aye! T' A8-3 be a pretty good match and t' ejection be at (or just before) apogee. Arrr! There seemed t' be some tail wiggle on t' way up, but it was straight overall. Avast! Aye aye! Recovery be fine, arrr, arrr, although t' wind really carried it. No damage.

My next flight was a repeat o' t' first on an A8-3, but on a calmer day. Well, blow me down! Begad! It too showed a little bit o' tail wiggle going up. Ya scallywag! Ejection was just before apogee and recovered it just fine.

T' next flight was on a B6-6. Avast! This time the "little bit o' tail wiggle" turned into a lot o' tail wiggle with larger circular motions. Blimey! Aye aye! It really looked bad, arrr, although t' flight was straight up. Avast, me proud beauty! Avast! T' ejection seemed t' happen perfectly at apogee.

T' rocket is showin' no wear. Begad! Everythin' is sound with t' exception o' me shockcord and streamer. Arrr! T' thread twisted a lot and t' streamer attachment is tore slightly.

For FLIGHT/RECOVERY, I would rate this rocket 4 ½ points. T' flight o' t' CAP Rocket is good but this wiggle could be a problem. Avast! Yes, yes, shiver me timbers, is it t' design or t' builder? Conceptually it could be t' builder and t' placement o' t' fins and such. Ya scallywag! It is kind o' like the Estes Blue Ninja that for me always has a slight wobble, Someone else noticed it too, so it could be t' rocket. Ahoy! We'll never know for t' CAP rocket, matey, unless someone else builds it.

I give t' rocket an OVERALL ratin' o' 4 ½ points. Avast, me hearties, me proud beauty! Hey, it is a "free" rocket and has some expendability t' a two-stage and egg-lofter. Ahoy! It provides other unique techniques for paper rocket building. Give it a try!

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