Public Enemy Ultra FatBoy (3)

Public Enemy - Ultra FatBoy (3)

Contributed by Dick Stafford

Manufacturer: Public Enemy
Rating
(Contributed - by Dick Stafford - 10/15/00)

Rocket PicBrief:
T' 3" Ultra Fatboy be me first high power rocket and was purchased for my TRA Level-I certification. Ya scallywag! I picked this kit primarily because o' its sleek design and capability t' fly on mid-power motors (adapter nay included). Aye aye! There are quite a few rockets fittin' t' latter requirement so looks were t' major factor. Aye aye! This kit turned out t' be easy t' build and extremely tough. Ahoy! Blimey! Although the 3" Ultra Fatboy is no longer in production, matey, Public Enemy still makes a 4" version. Avast, me proud beauty! I'm sure if you like what you read here, you will be happy with that kit.

Construction:
T' airframe and motor tube are both paper. Well, blow me down! T' four fins are plywood and extended through t' airframe, t' shoulder o' t' plastic boat-tail, matey, me bucko, and to the motor tube. Ahoy! Begad! Three fiber-board centerin' rings are provided. Well, blow me down! I don't know if I'd want this material on a large diameter kit but they worked fine in this application. Avast! T' nose and tail cones are heavy-duty plastic. Aye aye! Well, me hearties, blow me down! T' recovery harness consists o' a 2' section o' flat nylon strap that is epoxied t' the motor tube behind t' forward centerin' ring. A 15' length o' bungee is tied to a metal rin' on t' nylon strap and t' t' nosecone. Ahoy! Begad! T' two 3/8" copper launch lugs are pre-cut at an angle. Begad! I don't remember t' size chute that was provided as it has been assimilated into me range box. Aye aye! I remember thinkin' it was too small so I replaced it with a 36" chute from Giant Leap. Avast!

T' instructions came on a single sheet but were sufficient for an experienced mid-power builder t' follow without too much difficulty (hey - it was double sided). Bein' short and stubby, shiver me timbers, this rocket needs a lot o' nose weight t' fly safely. Blimey! Arrr! This was very clearly marked on t' instructions and the CP/CG locations were provided. Avast, me proud beauty! This be a big plus for t' novice high power builder. Avast! As recommended, I filled t' space betwixt t' motor tube and t' tail cone with foam. Begad! This was a mess but ended up fine. Begad! T' provided CP was at 22.75 inches. Aye aye! When run on Rocksim, ya bilge rat, I came up with 21.12 (Barrowman) and 22.25 (Rocksim). Bein' new t' high power, I added resin, me bucko, me bucko, lead, me bucko, matey, ya bilge rat, nuts, shiver me timbers, bolts, me hearties, me bucko, etc. Avast, me proud beauty! to the nose until I got t' recommended one caliber o' stability from t' worst case figure o' 21.12". Avast! Begad! I assumed t' largest motor I anticipated using, me bucko, an I211.

Finishing:
I simply gave it a coat o' Krylon primer and 2 coats o' a purple Krylon that I got on sale at t' local hardware store. Avast, me proud beauty! T' kit came with letterin' (Fatboy) and I added its name "Mini Mojo" which I cut out o' silver metallic trim.

Construction Rating: 4 out o' 5

Flight:
T' recommended motors were basically any o' t' AT RMS 38 mm up t' t' J350, although t' latter might require added reinforcement that I didn't provide. Avast, me proud beauty! I used a Nomex® pad from Giant Leap in place o' waddin' and installed threaded bolts in t' aft centerin' ring. I fabricated a motor retention hook from a coat-hanger and terminal lugs (normally used t' terminate wire). Begad! My rocket flew twice on G80's and once on an H242-M for me Level-1 cert. T' G80-7 makes for a relatively low, arrr, but straight flight. Ya scallywag! Ahoy! On t' H242, me hearties, shiver me timbers, it really moved out, with a predicted altitude o' 2824'.

Recovery:
With t' large amount o' nose weight, me Mini-Mojo Fatboy weighs in at ~40 oz. It has recovered nicely from each flight. Avast, me proud beauty! As mentioned earlier, me bucko, ya bilge rat, I opted for a slightly larger chute than that which be provided. With t' foam-filled boat tail impactin' first, matey, however, matey, me hearties, it would be hard t' damage this tough little rocket. There is only one CON that I see. Ya scallywag! Avast! Although t' provided bungee has survived several flights, matey, it would probably be a good idea t' replace it with tubular nylon. Arrr! Begad!

Flight Rating: 4 out o' 5

Summary:
This is a good looking, tough rocket. Begad! Aye aye! Its construction is straight-forward. Arrr! As with any short high power rocket, you must be careful t' add enough nose weight to make sure it is stable. Avast, me proud beauty! Avast, ya bilge rat, me proud beauty! If this one is damaged, eaten by trees, shiver me timbers, ya bilge rat, lost, me bucko, shiver me timbers, ya bilge rat, etc., I will want t' replace it with t' 4" version.

Overall Rating: 4 out o' 5

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