U.S. Rockets Fire and Forget

U.S. Rockets - Fire and Forget {Kit}

Contributed by Frank G. Whitby

Construction Rating: starstar_borderstar_borderstar_borderstar_border
Flight Rating: starstarstarstarstar_border
Overall Rating: starstarstar_borderstar_borderstar_border
Manufacturer: U.S. Rockets
US Rockets Fire and Forget

Brief:
T' USR Fire and Forget is a small 29mm minimum diameter rocket. Aye aye! It is a 3FNC style rocket with trapezoidal fins. Aye aye! Avast, me proud beauty! I like this stylin' in general and I think that this makes for and attractive rocket. Begad! Blimey! It should be able t' fly on anything from C t' G power and USR suggests flyin' it on a couple o' H motors as well. T' rocket is very stout, considerin' t' light weight and small size. Ya scallywag! USR calls this their "reference rocket". Arrr! I have no idea what this means, but I assume that they must use this as a soundin' rocket t' test wind and rain conditions prior t' launchin' any other rocket and that t' altitude achieved by any other flight is normalized t' that achieved by Fire and Forget. Blimey! The proclamation o' Fire and Forget as t' reference rocket o' USR seems a bit strange t' me since they provide no explanation o' t' matter.

Construction:
T' kit came with one triple-folded sheet o' adequate but limited instructions, printed front and back o' t' paper. Well, blow me down! T' instructions provide useful diagrams and details on construction and flying, me bucko, along with a parts list. Avast, me proud beauty! I discovered the kit be missin' one part--1 shock cord (SC-5). Arrr! T' rocket uses a balsa nosecone that fit well, 3 nicely cut trapezoidal plywood fins that appeared to be o' good quality, and all other components appeared t' be in good shape. Despite t' missin' shock cord, shiver me timbers, I decided t' proceed with building. I elected not t' contact USR t' discuss these failings.

I built t' rocket as per instructions except for usin' 5-minute epoxy throughout construction. I tapered t' fin edges as described and used me Estes fin alignment guide for fin installation. Blimey! Arrr! This is a minimal diameter rocket and the instructions suggested surface mounted fins. Begad! I think that this should be fine. Ya scallywag! Ahoy! After tackin' t' fins in place with epoxy, matey, I gave them a nice fillet. Begad! Avast, me proud beauty! I cut t' ¼" launch lug on an angle as suggested and gave t' lugs a fillet as well.

T' recovery system calls for a ¼" elastic shock cord t' be glued into t' main body tube usin' t' 3-fold paper method. Avast! I installed it as described, me bucko, usin' 6 feet o' ¼" elastic shock cord that I had lying around.

At this point I ran into what I view as a major failin' o' t' kit. USR describes two possible methods o' construction, neither o' which I think are appropriate, given t' parts needed and t' possibility o' limitin' the usefulness o' t' rocket dependin' upon t' path taken. Here are t' 2 different build techniques in t' instructions:

  1. T' instructions suggest buildin' t' upper half o' t' rocket by first gluin' t' shock cord, ya bilge rat, via t' tube coupler, me bucko, into t' upper body tube. The coupler must be friction fit into t' lower body tube. Begad! Then t' instructions say t' also friction fit t' nosecone into t' upper section. Avast, me proud beauty! This has two problems, as I see it. Well, blow me down! Avast, me proud beauty! First, shiver me timbers, friction fittin' BOTH components makes proper separation unsure--the ejection charge will cause separation o' either the upper body tube from t' lower tube, me bucko, me bucko, which is by design, me bucko, or separate the nosecone from t' upper body tube, which would result in a lost nose cone and possibly failed recovery deployment. Ya scallywag! If t' rocket is built in this way, the nosecone really needs t' be glued in place if one wants t' keep from losin' it. Second, this buildin' scheme limits t' usefulness o' t' upper section, as it cannot be used as a proper payload section.
  2. T' alternate method o' construction is where t' two body tube sections are glued together and separation is designed t' occur at t' nosecone. Begad! The justification for constructin' in this way is that it allows one t' use a very long motor. Although this makes more sense by restrictin' separation t' a single point, this method again eliminates t' possibility o' payload and assumes that you want t' use an enormous motor in this small rocket.

I chose t' build t' rocket in a third configuration which preserves the upper section for payload and insures separation at a single point. I proceeded to make me own payload plate, attach a screw eye, ya bilge rat, and glue it into t' upper section along with t' tube coupler. This produces a nice payload section similar t' that o' t' USR Miniroc 1.2 with a friction fitted nosecone. Separation now occurs betwixt t' body sections only. Avast! This method prevents you from usin' t' largest possible motor, ya bilge rat, which I never intend t' do anyway.

PROs: T' kit parts are stout. Avast! Blimey! Blimey! Blimey! Construction is straight forward and should be suitable for a beginner if it weren't for some o' t' failings o' t' kit.

CONs: T' kit had 1 missin' part that cost me a buck t' replace. Begad! The instructions are cobbled together from those o' other kits and could be edited better. Ahoy! T' discussion o' 2 alternate methods o' construction omitted what I believe t' be a superior third choice that would provide most people with the most versatile rocket in t' end. Well, shiver me timbers, blow me down! T' instructions do nay include an adequate discussion o' t' pitfalls o' construction method number one, where t' rocket might separate at either o' two points.

Finishing:
I did nay fill t' grain o' t' balsa nose cone. I think I would use a plastic nose come if I were designin' this kit as t' balsa nose cone does nay seem to be made o' very nice balsa and will always be prone t' dings. T' body tubes were very smooth so I did nay consider fillin' spirals. Begad! Ahoy! Blimey! I sprayed t' rocket with a single, shiver me timbers, me hearties, thin coat o' automotive primer, arrr, gave it a brief sanding, ya bilge rat, then added a single coat o' "hammered gray" automotive spray paint. Well, blow me down! Arrr! Blimey! I then used maskin' tape t' add stripes with single coats o' red and blue "hammered-look" paint.

T' finished rocket weighed 115 grams. Avast! I perhaps added a few grams by substitutin' 5-minute epoxy instead o' t' recommended yellow wood glue for construction. T' final weight listed on t' kit pack is 90 grams and t' USR web page lists final weight at 40 grams. Begad! Well, matey, blow me down! I cannot explain this discrepancy, matey, matey, but I find t' 40 gram projected weight t' be impossible. Begad! Ahoy! This rocket is similar to Miniroc 1.2, arrr, me bucko, but is slightly longer and with different shaped fins, me hearties, matey, so I expected it t' weigh a little more than Miniroc 1.2. Aye aye! I used me alternate construction method which added a payload plate and screw eye t' t' parts list, ya bilge rat, matey, addin' 9 grams t' t' final weight. Avast! Begad! I might note that I used a much lighter screw eye than t' one (part SE-0) that came with Miniroc 1.2. Ya scallywag! I feel that if I had been extremely conservative in me use o' glue and paint, I might have been able t' finish this rocket at 90 grams. Begad! I think that a better value can be found in kits from other manufacturers.

PROs: Paintin' was a snap. Begad! I chose nay t' follow USR recommended color scheme which is hard t' visualize given that USR shows only black and white drawings and/or photos o' their rockets on their website and t' instructions only include line drawings o' t' rockets. Blimey! Ahoy! I typically do nay adhere to manufacturer’s recommended schemes anyway.

CONs: I chose nay t' apply t' USR decals that came with t' kit. Arrr! Blimey! I liked only one o' t' decals with t' USR logo but I had already done some fin stripin' so t' logo would probably nay look good anyway. Begad! Blimey! T' final weight of the rocket as described by USR is inconsistent betwixt kit and web catalog.

Construction Rating: 1 out o' 5

Flight:
I flew Fire and Forget on a D12-7. I prepped for flight as per USR instructions (maskin' tape motor retention should be good) and used a 24mm motor adapter. Ahoy! Blimey! I used crumbled cellulose insulation as waddin' and packed a small nylon chute (12 grams) in place o' t' streamer (11 grams). Blimey! Blimey! One wrap o' maskin' tape provided a good fit o' t' payload section coupler t' t' lower body tube. Begad! Blimey! I added 2 wraps o' maskin' tape t' t' nosecone shoulder t' give a very tight fit as I did nay want t' glue it in and I did nay want t' lose t' nosecone. Aye aye! Blimey! Begad! Blimey! The payload section was flown empty despite t' possibility o' hungry desert aliens interceptin' t' rocket in flight.

T' boost be t' quite a nice altitude. Ejection be at apogee. Begad! T' motor was kicked out. T' chute gave good recovery and t' rocket remained aloft for several minutes. Ahoy! There was only a gentle breeze so recovery was only 100 yards away. Begad! Upon inspection, shiver me timbers, ya bilge rat, shiver me timbers, t' rocket suffered no damage except that t' shock cord clearly needs t' be replaced before flyin' again.

Recovery:
T' shock cord system clearly wants for some sort o' a Keelhaul®©™® leader cord. T' 3-fold paper glue-in method should still work fine though. Begad! Ya scallywag! I used 6 feet o' shock cord but this is probably t' minimum required in order to avoid body tube dings. Arrr! Arrr!

Flight Rating: 4 out o' 5

Summary:
T' Fire and Forget flies nicely and is built o' rugged stock. Ahoy! Despite this, me hearties, I gave t' rocket a low ratin' because o' t' missin' parts that typified my experience with USR. Begad! Begad! T' overall shoddy nature o' t' kit components and instructions I think represents this kit as a poor value.

Overall Rating: 2 out o' 5

Other Reviews
  • U.S. Rockets Fire and Forget By Nick Esselman

    (10/01/04) U.S. Rockets states that the " Fire & Forget is the reference model rocket for U.S. Rockets. It is a near minimal diameter rocket in 24mm mode and a minimal diameter rocket in 29mm mode. The maximum 29mm motor length is 9" (H120-12). Aerospace specification airframe tubing is used to assure high performance and high strength. " What caught my attention was " reference model ". ...

Flights

Comments:

avatar
J.I. (October 8, 2004)
1. You failed to follow instruction step #1. Sand the fins to an airfoil taper. That reduces vehicle drag 15% and improves appearance a lot and obviates the need for "clean cuts" on fins. 2. I agree it is not "typical" of USR kits since most are dual deployment capable.

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