ROL NEWS--Sky Ripper Motors Certified

Sky Ripper Motors Certified July 9, 2004 Web posted at: 4:34 PM EDT

(ROL Newswire) -- Sky Ripper Systems, makers of hybrid rocket motors for the sport rocketry community, is happy to announce their first product line: the Sky Ripper Systems 38mm motor system. This motor system is unique in several ways and offers great flexibility to all sport rocketry enthusiasts.

Sky Ripper hybrid systems currently are certified for use with multiple fuel types. Level 1 and level 2 fliers can choose between PVC and polypropylene fuels, depending on the flight profile desired. PVC produces lower average thrust rates, dark black smoke and a sound that is much like that of a solid motor. Polypropylene features a higher average impulse, more total impulse and a very loud hybrid-style combustion.

The reload kits are identical for all motor hardware, so one reload kit can be either an H, I, or J, depending on the hardware it is installed in. Ignition supplies are included with the reload kit and can be shipped by qualified dealers via USPS, with no hazmat charge required.

All internal motor components are identical, so the same injector and nozzle work for each of the six motor types. The durable snap ring based cases insure easy assembly and are compatible with both Slimline and Aeropak motor retainers.

Tripoli Motor Testing has certified the following 38mm reload kits and Sky Ripper Systems hardware for sport rocketry use:

Hardware: Fuel: Designation:

38/220 PVC H-124 38/220 Polypro H-155 38/400 PVC I-119 38/400 Polypro I-147 38/580 PVC I-117 38/580 Polypro J-144

For more information and a dealer listing, please visit

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Source: Sky Ripper Systems

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Just a personal note...I have helped demo these motors and they absolutely Rock...They are extremely simple to use and provide excellent lift capability. I received delivery of my hardware last week and will put them through their paces at this Saturdays Launch with the Jackson Model Rocket club at MIS....can't wait...oooh can't wait....and I hear they may have a 29 mm Hybrid G motor and 54 mm hardware hiding just around the corner....The hardware is flawless...well thought out...and well machined....and a great shade of Blue.

Mark A Palmer TRA 08542 L3

Reply to
Mark A Palmer

Little late, but I always wondered how these hybrid companies got away with selling plastic and rubber tubes for more than a couple bucks each.

Pax

Reply to
Paxton

They are "certified".

:)

Jerry

Reply to
Jerry Irvine

Aloha, It is called "profit". They are betting that you will be more willing to pay their price, than to do it yourself. It is the same as the convenience store. More conventient, but higher cost.

Larry

Reply to
AkaZilla

The hardware gets sold to fliers somewhere near cost. If you want the various companies to continue to be in business, then you must expect them to actually make a small profit on the reloads.

YES, the Propulsion Polymers, West Coast Hybrids, and Sky Ripper motors burn lightly-machined !plastic pipe!. Cutting and machining that pipe into consistent fuel grains for hybrids incurs non-zero production costs. Add to that the other consumables ('O' rings, 10-15ft of nylon hose, insulator sleeves, insulator washers), and a coupla bucks a reload starts to look like a money-losing proposition to me.

The meagre profit made from reload sales goes into keeping the companies going, developing new products, maintaining websites, travelling to the occasional launch to Beta/demo new product, get product certified, etc, etc. Ain't no yachts in the mediteranean for us hybrid folk, that's for sure...

Ammonium Perchlorate is about $8.00/lb in quantity--when was the last time you paid $8.00 for a light APCP 'J' motor that you didn't build yourself? Yeah, thought so...

Reply to
Marcus Leech

Let me educate you, Paxton.

The material that the fuel grain is made out of is one of the cheapest components of the reload kit, and I tell people that every time they say to me 'Boy.. It seems like you should be able to use this grain twice.'. There are no secrets here. Labor in machining the tube adds more to the cost of the reload than does the raw material. This is something that you may not understand. If I were making five of these grains for my personal use in my garage, I would most likely look at only the cost of the material, discounting my time investment. When I stand in front of the lathe for 10 hours making hybrid grains for retail sale, however, I have to be compensated for my time. Why would I do it otherwise?

There are also many other parts in the reload package, some with higher price tags. My kits, for example, come with the pyro devices and they aren't cheap. I package these pyro components in a seperate anti-static bag. I had to buy the bag as well as pay somone to put these parts into that bag and heat seal it. Nozzle liners, fill tube, sleeves, O-rings.... Some of these items require work before they are ready to be sold, and someone has to put all this stuff in a retail bag and seal it as well. It all takes time. Time=money.

We are BLESSED in the hybrid community by having a GREAT dealer network that believe in our products, and really work hard getting our wares out to the flyers. These dealers also expect to be paid for their hard work. Why would they do it otherwise?

If you look at this stuff in terms of raw materials only, you might think all rocketry products are over-priced. I'd say you are only looking at the smallest percentage of costs.

Todd

Reply to
Todd Moore

I've always wonders how people that think moronic things like this remember to breate.

Reply to
Phil Stein

This should be in the FAQ.

Reply to
Jerry Irvine

So where is your inexpensive hybrid system?

Tony Haga

Reply to
Tony H.

Aloha, I do not grudge them a profit. I hope they make a million bucks. That will make sure we have a motor supply for a long time. The reason I made my comment, "someone" started making noises about certification and I did not want this to degenerate into another argument about certification, DOT, shipping, etc.

Larry

Reply to
AkaZilla

If it doesn't it will have to degenerate into TRA corruption with the usual accusatons by the usual suspects.

Reply to
Phil Stein

Actualy I think they should give away the case hardware free, or at least provide a lifetime free replacement garantee against loss or dammage. Of course I'd also like to se more SU motors available. It is nature of the beast.

Alan

Reply to
Alan Jones

If you'd like to see reload costs go up by 50%, that just might be a possibility.

Consider this... By the time a particular motor makes it to market, the manufacturer has gone through multiple iterations of the motor, and LOTS of test-firings. That all costs money, not to mention the time involvement.

All that is an investment that the manufacturer HOPES to make up by selling reloads; we already know the hardware itself is at, or near, cost. At the lousy margins most of this stuff is sold at, it takes a LOT of reloads, especially on smaller motors, to make up that initial investment.

If the manufacturer gives away the hardware, it puts them that much further behind in making up their initial investment.

-Kevin

Reply to
Kevin Trojanowski

"The beast" is against SU motors being widely available.

Reply to
Jerry Irvine

No way. Even if cases were given away free (like when purchasing 8 loads for example), then it would work. The money is made on the reloads. Why do you think there is so much incessant whining about reload costs because they include "a hunk of plastic"?

A "certified" hunk of plastic BTW :)

Reply to
Jerry Irvine

With you "heckeling".

Reply to
Jerry Irvine

I look forward to YOUR motors being certified soon. I'm sure you will be giving away the hardware at that time. Will that be before or after you finish your business degree?

Reply to
Alex Mericas

Yep. Most folks don't want to pay the higher costs of single use motors, especially for larger motors. With small motor that are flown frequently (and often clustered) it's worth paying a bit more to avoid the hassle of cleaning and assembling between every launch.

Reply to
RayDunakin

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