U.S. Rockets All Weather

U.S. Rockets - All Weather {Kit} (1013)

Contributed by David Urbanek

Diameter: 2.25 inches
Length: 24.00 inches
Manufacturer: U.S. Rockets
Skill Level: 1
Style: Sport
Rating
(Contributed - by David Urbanek)

Brief:
Very basic mid-powered rocket. Easy to build and it flies very well.

Construction:
Normal paper body tube and motor mount. Balsa nose cone (when was the last time you saw that in a mid power kit). The centering rings are very cheap, poor quality and splintery. The fins are also cheap plywood and one was slightly warped. There was no provision for motor retention. Elastic shock cord was pretty much par for the mid-power course. The parachute was paper, and fairly high quality. The launch lug is a 1/4" mylar lug (like Estes, just fatter). The 29 mm to 24 mm adapter is one of the better ones out there and I've standardized on this design. It works wonderfully and is light weight, as long as you use some form of mechanical retention.

RockSim Diagram

The rocket is meant to have surface mounted fins and for such a light rocket, I saw no reason to change that. A good epoxy joint is more than strong enough for this light rocket. I added a #6 blind T-nut and a screen door clip to hold the motor in place. Good epoxy joints on the motor mount makes is plenty sturdy enough. I added a length of light, tubular Kevlar® (available from Pratt Hobbies) to the forward centering ring for the recovery system attach point. I fiber-glassed the body in a single wrap of 2 oz fiberglass cloth and I applied the same to the fins. This gives a very strong surface and makes the rocket last longer. I expect this rocket to get a lot of flights. The fins were attached with a thick bead of 5 minute epoxy. Then I filleted the sides of the fins with the same epoxy. I attached the launch lug with 5 minute epoxy as well. I threw out the elastic shock cord and substituted a good 10' of braided nylon cord. This is attached to the tubular Kevlar® and gets it out of the way of the ejection charge. I added a Nomex® shield so I don't have to use wadding (I hate wadding in bigger rockets).

Finishing:
After sanding the fiberglass surfaces, I applied 2 coats of sandable, scratch filling primer. This was followed by two coats of flat white Krylon. I received a new airbrush for Christmas and since I had some of this obnoxious Tamiya pink paint left over, I used that. I didn't have quite enough to really finish the job. The paint scheme is a work in progress.

Construction Rating: 2 out of 5

Flight:
When you look at it, it's the very image of a basic rocket. Nice lines actually. It flies very well too. So far all the boosts in calm weather have been very straight. Wind does cause some weather cocking, but not too much. The rocket is of a very standard shape, so most altitude prediction software will be accurate with this design.

Recovery:
I'm using a 3' long piece of tubular Kevlar® attached to the forward centering ring. This is then attached to about 10' of braided nylon. The parachute is attached via snap swivel in a loop at the shock cord end. The nose cone is attached to a loop about 3' down from the parachute. The Nomex® shield is attached where the Kevlar® meets the nylon. I need to get a bigger shield. I'll probably get one form Rocket Rage. I liked the looks of their stuff at ROCStock. Right now I'm using a smallish Pratt shield and I get a hole in the chute every other flight. Descent on an 18" chute is very fast, but doesn't seem to damage the rocket and minimizes the drift.

Flight Rating: 3 out of 5

Summary:
PROs: It's easy, cheap and pretty much a normal beater rocket. I'm expecting this to be my sounding rocket that I fly to check launch conditions. PROs: It's nice shape and has good lines. It flies really well on E and F motor and really moves out on Gs, so it's cheap to fly. CONs: The entire stock recovery system needs replacing. CONs: Typical balsa nose cone problems. You'll forever be repairing nose cone dings. No big deal for those who know about balsa nose cones, but it might be a problem for plastic nose cone folks.

Overall Rating: 3 out of 5

MANUFACTURER's OPINION:
"7/00 - I noted the comments made by Mr. Urbanek regarding motor retention not being considered in the USR All Weather kit. I find this comment to be simply not true. In fact motor retention is one of the central BENEFITS of all USR kits as outlined in AIR-3 included in all cluster kits and AIR-1 included in all kits. I cannot speak for "upgrades" since I [didn't] designed them, but the kit was built incorrectly according to the wonderful rocsim drawing the reviewer provided. I believe a review should at least include a discussion of the stock design even if the builder replaces the recovery system so hailed by other reviewers." (J.I.) 

AUTHOR's RESPONSE:
"7/00 - AIR-1 discusses the wisdom of avoiding thrust rings in the motor tube and the use of tape thrust rings (hardly new ideas). In fact, AIR-1 (figure 4) extols the virtue of the Irvin's Motor Installation Method which has the advantages of "...unlimited motor length as well as secure ejection retention". This method uses a motor hook. No motor hook, however, was included in the kit. I had to ADD something to the kit to effect ejection retention. As the kit was, even the parts needed to implement AIR-1 were absent. Hardly a benefit.

It was not built incorrectly. Perhaps this writer is not aware that US Rockets has changed the All-Weather design so that it is now sold with a 29 mm motor mount.

Here are the changes I made. All of them were to make the basic kit more durable:
1: Added 1 layer of 2 oz fiberglass to body and fins. In retrospect, 1/2 oz fiberglass would have been better and lighter, but I used what I had on hand.
2: Added single T-Nut, screw and hook for motor retention
3: Anchored e feet of tubular Kevlar® to forward centering ring.
4: Tied 10 feet of braided nylon to the Kevlar®.
5: Replaced 18" paper parachute with 18" nylon parachute
6: Added a Nomex® shield.
7: Didn't cut the cut the launch lug in half.

Modification added 112g, or about 4 oz to the predicted weight. I don't think that a painted All-Weather would ever weigh a mere 4.8 oz though.

The stock recovery system was a simple, unimaginative upscale of an Estes recovery system. A length of elastic was to be attached to the body tube wall by means of a folded paper anchor. The parachute was a cheap paper chute (yes paper). To my mind, this parachute was going to be hard to protect adequately, and if it did ignite, might pose a fire hazard.

Far from being 'hailed', US Rockets, without exception, has the worst recovery systems in the business. The All-Weather's recovery system was the cheapest one can get away with. The 'recovery system' that I received with my high power Mega-Roc was an insult. They actually thought that I should try to recover a 4" diameter x 84" long rocket with four 24" parachutes. And what parachutes! They barely qualified for that name. They were 4 octagons of very thin, very porous fabric, not hemmed, not finished, but cut out with pinking shears. There were eight holes poked through the edge of the unfinished fabric and each suspension line was tied to the canopy by means of a single knot. Utterly appalling.

So don't talk to me about US Rockets recovery systems. They were the very worse features of otherwise passable kits." (D.U.) 

Flights

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