rjungcla@ihlpb.ATT.COM (R. M. Jungclas) (01/28/89)
I have been trying to respond to this for a few weeks, but things really bogged down at work and things are only slowly returning to normal. If you requested a list of rocket manufacturers, I will email you a copy as soon as I get caught up. So better late than never ... >Model rocketry may claim millions of accident free launches as a proud >heritage. That is fine for a pure MODEL hobby that is done for family >fun, for creative pleasure and so on. I won't knock it. I used to be a >model RAILROADER myself. Same difference. While I concede that the largest percentage of model rocket launches are done for fun, model rocketry/high power rocketry is more than a "pure MODEL hobby." Both of these have made positive research contributions. Unlike model railroading and other "imitation" hobbies, once a model rocket leaves the launcher all aerodynamic and structural principles apply. Only the magnitude of the forces differ. In many cases, the magnitude of forces, etc. are insignificant in studying the research issues; major aerospace companies use a "static" modeling capacity in studying research issues and designs. Because of the medium used in model/high power rocket construction, is often easier, safer, and considerably less costly to study structural failure. For example, it is easy to build a vehicle that exceeds "the speed of balsa." When this happens the forces applied to the vehicle exceed the tensile strength of balsa fins. Professional rocket engineers obviously don't talk about balsa, but the underlying principles are identical. There have even been investigative efforts into what it would take to place model/high powered rocket into orbit. Finally, there is also an R&D mechanism present within the NAR and presumably within Tripoli. The bottom line is that model/high power rocketry is what YOU make out of it. It can be a inexpensive way to complete research. Let me now site several research examples: 1. In 1966 James Barrowman developed a method for finding the stability of new model rocket designs. This approach eliminated the previous trial by error approach and used a greatly simplified approach based on stability design by professional rocket engineers. This technique so greatly simplified and produced reliable results that the stability design used by professional engineers adopted the approach for sounding rocket designs. 2. Considerable effort have gone into developing highly accurate altitude/speed prediction programs that take into account every conceivable factor and yet are available for most microcomputers. 3. A friend of mine has developed a miniature video camera, transmitter, and on board computer that fits inside an Estes PNC-80K nose cone - about 2.6 inches in diameter and 4 or 5 inches in length. The battery pack by comparison is almost as big!. This design was studied by a major robotics/machine vision corporation and Lionel trains who within the past year released a similar but drastically less complex video camera of their own. The original rocket design was considerably larger. This person was not the first to fly a video camera, but it illustrates what I call the "American" approach (ie miniaturization) vs. the "Russian" approach (strapping an off-the-shelf video camera/recorder to front end of a launch vehicle and flying it) 4. By the late 1960's, model rockets had demonstrated the Space Shuttle concept of launching like a rocket and gliding back to earth identical to present real Space Shuttle concept. (True, we didn't make it to orbit, nor did the hobby invent the concept) 5. >A high power rocket built by North Coast Rocketry and carrying a >research payload was recently launched (past 6 months) from Cape >Canaveral after months of red tape. Mark Johnson (Mark.Johnson@Wichita.NCR.COM) reports info on LOFT-1: The flight was launched from Canaveral Air Force Station on November 17, 1988 at 0745 EST, reaching an altitude of 3.25 miles. (LC 47 was the launch site, using a modified Loki-Dart launcher; telemetry was set up at LC 41). The vehicle itself and the Vulcan N5000-20 motor performed essentially perfectly, although E-Prime's aneroid main-chute deployment feature failed to eject...it was rigged to reduce drift by holding the main chute until the vehicle reached an altitude of 3000 feet on the way down, and it got fried by the ejection charge on the motor, which was used to eject a 24" (or so) drogue chute. The drogue chute thus was the only recovery system on the bird, which suffered only minor damage on splashdown. The flight vehicle was recovered within 1 hour of the flight, and was opened up in front of the news media shortly thereafter. Telemetry data was received the entire time the vehicle was airborne. Several NAR members were involved in the project in various ways: (The LOFT effort is NOT an NAR activity, but rather one that some NAR members branched out into by applying their model rocket technology and experience.) Matt Steele, part-owner of North Coast Rocketry, designed the vehicle and did some or most of the construction. Project engineer with Morton Thiokol-Huntsville. J. Wayne McCain, a PhD candidate at Univ. of Alabama/Huntsville, was payload integration manager. Wayne is an amateur radio operator. David Babulski, longtime MR telemetry builder (his series is currently running in AmSpam), ran the telemetry ground station for the flight. Dave is employed as a curriculum developer/trainer with Harris/3M in Atlanta (copiers, fax machines, etc.) Dave is also an amateur radio operator. Some other details...one of the original payloads scheduled to be launched on LOFT was a high-school biology experiment, coordinated by Dave Babulski, from Brookwood High School (east suburban Atlanta). When LOFT was repeatedly delayed, Dave, Wayne, and North Coast put together a replacement vehicle, called BABE-2 (the original experiment package was BABE-1), which was flown from Huntsville (Redstone Arsenal) last spring. This vehicle was powered by a Vulcan I283 and reached an altitude of 10,000 feet...15,000 had been projected but a structural failure occurred in the bird at Mach 2+ causing the vehicle to break up and the payload did a free-ballistic number. The experiment package was recovered with only minor damage, somewhat surprisingly; I think telemetry even survived the aerial breakup although it stopped rather suddenly on meeting the region of extreme drag coefficient known as earth. Another friend of mine reports that details of this flight are reported in a recent issue (January?) of Discovery magazine. >But the kind of rocketry that is likely to produce useful results is >also unlikely to be able to sustain such a record. If it did, it would >not be pushing the state of the art and would not be accomplishing >anything real. Again, we must look at volume of "fun" launches and subtract these. Don't confuse safety with failure. Pushing the state of the art does not necessarily imply lack of safety. Pushing the state of the art does mean failures and correcting the reason for these failures. >I found the article on Model Rocketry quite informative and >interesting, but I must say that I'm personally not interested in >building 'model' rockets. I've not really been in the hobby at all, but >if I were I'd definitely go into the amateur rocketry category with >intent to test new untried or undertried concepts and possibly to put >something in orbit. With or without permission. By the poster's own admission, he has never checked out the details of the hobby. Any good researcher will check previous work done in their field, related fields and any activity that could benefit their research. Model/High power rocketry can provide an excellent, inexpensive and a safe way without all the legal hassles in which "to test new untried and undertried concepts" without re-inventing the wheel. High power rocketry can trace it roots back to research and/or military applications. This does not imply that model/high power rockets are useful in every case; only that if they can be used it probably in researcher's best interest to do so. A good reference for a more detailed, in depth treatment of model rockets and theory/research behind them, consult G. Harry Stine's "The Handbook of Model Rocketry" that may be found in many libraries. >I personally know someone who has successfully fired a large >(suborbital class) teststand engine with an interesting hybrid type >fuel system. He and his crew did so in a very isolated area with >appropriate safety precautions. Their method of dealing with >bureaucracy is one that Admiral Grace Hopper would have approved of: >"It's easier to ask for forgiveness than to get permission." What they >don't know can't be regulated. No one is going to stop you from developing or static testing anything on your own property, provided you don't create a public nuisance (ie. noise) and don't create a public safety hazard (ie building your own nuclear warhead). However, the minute that you do this on public property, or in the national airspace, regulatory agencies will subject you to close scrutiny. Do you honestly think that an attempt to launch into orbit will occur without the appropriate agencies finding out about it? You might start to get away with it, but I guarantee that sooner or later you'll get caught and your research project is likely to be destroyed in the process. Moreover, ignorance is no excuse. I know of a case in which an individual attempted to use this approach that resulted in severe financial penalties and an agreement by the party involved to keep him out of jail that prevents him from attempting any rocket activities for life. Turns out that regulatory agencies really make examples out of these cases. So if you pursue this course of action be prepared for the consequences. R. Michael Jungclas UUCP: att!ihlpb!rjungcla AT&T Bell Labs - Naperville, IL. Internet: rjungcla@ihlpb.att.com
mmm@cup.portal.com (Mark Robert Thorson) (01/30/89)
Since you can't legally build your own amateur engines, I'm wondering about the other parts of the bird. Is it okay to build your own housing for a engine? Can you do experiments with manuvering and guidance? Let's say I build a rocket with an infrared quadrant detector linked to movable surfaces. If I use Estes engines and go somewhere legal for conventional rockets, would I be breaking any laws if I launched a rocket, and then shot it down with a second rocket (assume no explosive in warhead, just kinetic energy)? If I added rockets to a conventional R/C model airplane, for example to assist takeoff, would that be considered a model rocket or what?
rjungcla@ihlpb.ATT.COM (R. M. Jungclas) (02/02/89)
>Since you can't legally build your own amateur engines, I'm wondering >about the other parts of the bird. Is it okay to build your own housing >for a engine? Can you do experiments with maneuvering and guidance? Yes, you are free to experiment with other parts of the birds including maneuvering and guidance if you stay within the applicable (model vs. high power) safety codes. The limits to be concerned about are "non-metallic" structural parts and any weight limits. I had a friend who routinely "manufactures" his own fiberglass and carbon filament tubes (BTW not an inexpensive proposition.) >Let's say I build a rocket with an infrared quadrant detector linked >to movable surfaces. If I use Estes engines and go somewhere legal for >conventional rockets, would I be breaking any laws if I launched a rocket, >and then shot it down with a second rocket (assume no explosive in warhead, >just kinetic energy)? As long as you operated the vehicles within the prescribed safety code, this would be LEGAL. I would urge you to present this in a slightly different way to avoid the negative image that "shot it down" conveys. In particular, I would present this as a "dynamic mating or tagging of vehicles." BTW, I quote from the G. Harry Stine's safety report that the study of potential weapon use of model rocket components "tended to substantiate the US Army Ordnance data on the Loki rocket and indicates that the probability of a model rocket hitting a designated target is infinitesimally small - on chance in 14 billion for each launch with a 95% confidence level." >If I added rockets to a conventional R/C model airplane, for example to >assist takeoff, would that be considered a model rocket or what? Good question since it sent me back to the technical definition of what is a model rocket. A rocket assisted conventional R/C model airplane is NOT a model rocket. If this model airplane meets all other provisions (construction, weight etc.) for the definition of "model rocket," the provision under which the above case would fail to satisfy the definition would be "Its model rocket motor is ignited ... meeting the safety standard established by the NFPA/NAR/HIA." The NAR/HIA safety code requires all model rockets be launched within 30 degrees from vertical. Hence any conventional R/C model airplane requiring a horizontal take-off would clearly not be a model rocket. Would a conventional R/C model airplane using a near vertical liftoff be consider a model rocket? This is not as clear cut, but answer is probably no under the same provision since a conventional R/C model airplane is not designed (hence not safe) for a vertical takeoff. This Friday (2/3/89) I should be seeing a NAR representative at our club's meeting. I will discuss my comments presented here with him and get his (and NAR's) view, and post any clarifications or corrections to what I said above. I would like to ask what the poster's intent for this last question. Why do you want to view a rocket powered conventional R/C model airplane as a model rocket? R. Michael Jungclas UUCP: att!ihlpb!rjungcla AT&T Bell Labs - Naperville, IL. Internet: rjungcla@ihlpb.att.com
mmm@cup.portal.com (Mark Robert Thorson) (02/09/89)
R. Michael Jungclas writes: >"non-metallic" structural parts and any weight limits. I had a >friend who routinely "manufactures" his own fiberglass and carbon >filament tubes (BTW not an inexpensive proposition.) Can you tell me where he obtains his carbon filament material, and how much it costs? What equipment does he use for winding? >Why do you want to view a rocket powered conventional R/C model >airplane as a model rocket? I didn't mean to imply this would be desirable. Obviously, if I'm going to do it, I want the least regulation possible. If your interpretation of "model rocket" is correct, does that mean a rocket fired from an R/C airplane model is also not a model rocket? Gee, that sounds like fun!!!
mjohnson@encad.Wichita.NCR.COM (Mark Johnson) (02/11/89)
In article <14446@cup.portal.com> mmm@cup.portal.com (Mark Robert Thorson) writes: >of "model rocket" is correct, does that mean a rocket fired from an R/C >airplane model is also not a model rocket? Gee, that sounds like fun!!! That is correct...a rocket fired from an RC airplane is NOT a model rocket... it is not being launched in a safe manner AND is _NOT COVERED BY AMA OR NAR INSURANCE_. Sorry for the strident emphasis, but we've had such a battle with the states keeping model rocket products available on a general basis that I'm overly sensitive to anyone who talks openly about misusing them! To meet the definition of 'model rocket' the following elements are necessary: (excerpted from memory from FAR Part 101, subpart C (47CFR101) - gross weight under 1 lb. - propellant weight under 4 ounces. - made of fragile materials such as paper, plastic, and lightweight woods. - launched so as not to create a hazard for persons on the ground or other aircraft. - specifically NOT launched against any target, on the ground or in the air. - containing no warhead or intentionally explosive device. these regulations are contained in, and expanded upon, in the NAR's safety code. -- Mark Johnson (Mark.Johnson@Wichita.NCR.COM) WB9QLR/0 (Monon RR enthusiast) NCR Engineering & Manufacturing-Wichita, KS phone: (316)636-8189 email:...!rutgers!hplabs!hp-sdd!ncr-sd!ncrwic!encad!mjohnson US snailnet: 3718 N. Rock Rd., Wichita, KS 67226