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

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

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). Aye aye! Arrr! Bein' short and stubby, this rocket needs a lot o' nose weight t' fly safely. This was very clearly marked on t' instructions and the CP/CG locations were provided. Ahoy! Aye aye! This was a big plus for t' novice high power builder. Avast! Avast, me proud beauty! As recommended, I filled t' space betwixt t' motor tube and t' tail cone with foam. Arrr! Arrr! This be a mess but ended up fine. T' provided CP be at 22.75 inches. When run on Rocksim, I came up with 21.12 (Barrowman) and 22.25 (Rocksim). Aye aye! Bein' new t' high power, I added resin, lead, me bucko, nuts, me hearties, ya bilge rat, shiver me timbers, bolts, etc. Avast! Ahoy! to the nose until I got t' recommended one caliber o' stability from t' worst case figure o' 21.12". I assumed t' largest motor I anticipated using, an I211. Avast, me proud beauty!

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. Well, blow me down! 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. Begad! Begad! I used a Nomex® pad from Giant Leap in place o' waddin' and installed threaded bolts in t' aft centerin' ring. Ahoy! Aye aye! I fabricated a motor retention hook from a coat-hanger and terminal lugs (normally used t' terminate wire). Ya scallywag! My rocket flew twice on G80's and once on an H242-M for me Level-1 cert. Begad! T' G80-7 makes for a relatively low, but straight flight. On t' H242, it really moved out, with a predicted altitude o' 2824'.

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

Flight Rating: 4 out o' 5

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

Overall Rating: 4 out o' 5

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