As we celebrate the 227th anniversary of our country's formal declaration of independence this coming Friday, it's always useful to review how we've evolved since then as a nation.

While I'd be the last to urge anyone to forego the barbecue and beer, and other festivities that have become de rigeur in recent years, I also believe that the event is one to be commemorated, as well as simply celebrated. Which is to say, that I urge all to take a few moments, as sadly too few do, and print out and read (or hopefully reread) Thomas Jefferson's work of genius, and reflect on why so many died then, and since, to preserve the idea that we have certain "inalienable rights."

In light of current events, it's also useful to remind ourselves that "...whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government, laying its foundation on such principles and organizing its powers in such form, as to them shall seem most likely to effect their Safety and Happiness..."

Along those lines (I'll explain why in a moment), there is another activity in which we partake on this date that is both a celebration and a commemoration. As dusk approaches, we settle in to watch a display of pyrotechnics that are at once not just awesome and beautiful, but a stark reminder of the price that must often be paid for freedom, in blood and treasure. In fact, it is memorialized in the words of our national anthem, by Francis Scott Key.

Of course, the rockets that we enjoy in our celebration are closely related to some of the weapons of war by which we won our liberation then, and in fact, for decades, and even today, still represent the ultimate weapon when tipped with nuclear warheads. Fortunately, yet more rockets are being developed that may finally render such devices relatively impotent.

But rockets have peaceful uses as well, and not just for fireworks displays. For decades, many young people (including yours truly, back when I was a young person) have built and flown model rockets, often as a prelude to a later career in aerospace engineering. Today, the sport has evolved to the point at which amateurs are about to actually launch payloads into space. The most common propellant for solid-propulsion model rockets is ammonium perchlorate composite propellant (APCP).

Sadly, the misnamed "War on Terrorism" ("terrorism" is a tactic, not an enemy--we are actually at war with radical Islam and Arab nationalism) is about to claim this hobby as another victim. The newly-formed Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATFE--formerly the Bureau of Alcohol, Tobacco and Firearms) managed to slip something called the "Safe Explosives Act" into the broader Homeland Security Act signed by President Bush last fall. In it, APCP became a controlled substance, and rocket motors containing more than 62.5 grams of it (only a couple ounces) were essentially reclassified as explosive devices.

This is a misclassification over which the rocketry community has been fighting the agency since APCP first mistakenly appeared on the list of explosives back in the '70s, and they've never been able to get them to remove it, despite pressure from sympathetic legislators. For example, in a letter to the ATFE director, Senator Mike Enzi (R-WY) wrote:"Congress defined an explosive as any chemical mixture or device whose primary or common purpose is to function by explosion. I am told that the ATF claims that the primary or common purpose of a rocket propellant (i.e., ammonium perchlorate composite propellant) is to explode. A rocket propellant is not designed or intended to explode."

The agency continues to refuse to budge, however. An attempt has been ongoing to get a regulatory exemption for the hobbyists through legislation. Such legislation (Senate bill S724) has been approved by the Senate Judiciary Committee, but it continues to place undue restrictions on model rocketry in terms of allowable propellant loading, and it only exempts APCP, leaving open the possibility that ATFE could restrict other (perhaps safer and more effective) propellant types in the future by placing them on its explosives list.

The Justice Department, predictably, is fighting such a change, but their stated fears of home-made anti-aircraft and anti-tank weapons, and their misunderstanding of the difference between detonable and non-detonable APCP are, frankly, laughable to anyone who actually understands the technology.

When it comes to decisions with potential implications for public safety, it's natural for a bureaucrat to want to err on the side of caution, but there are often unintended consequences (e.g., my point that it might actually make it more difficult to develop safer propellants). There are no risk-free choices, and in a free society, we must often make compromises of security versus freedom. In a sense, that's what the "War on Terror" is all about--how to maintain the proper balance. If our freedoms become too restricted as a result, then it can truly be said that the "terrorists win."

Ignoring the fact that the hobby of building model rockets has created at least a couple generations of rocket engineers, some argue that still, it is "just a hobby," and can't justify the possibly increased risk to the public welfare of reducing restrictions. Given the political response, perhaps it's been a mistake for the hobbyists to paint their endeavors as harmless and educational, because other than the obligatory "pursuit of happiness," there's no apparent constitutional right to entertainment and hobbies.

Ironically, if they were to return to their roots, and proudly proclaim their projects as weapons, then perhaps they could find a sympathetic court under the Second Amendment.

In any event, as we watch the rockets fly on Friday, we should reflect and be thankful that we haven't yet lost the freedom to view the fireworks with which we celebrate all of our freedoms.

Dale Amon was talking some months ago about a hybrid rocket that was just a hollow cylinder of butyl rubber with an oxygen injector on the top and an exast nozzle on the bottom. This seems simple enough to apply to models.

Actually, many modelers, particularly in the high-power rocketry organizations, do use hybrids. And with nitrous oxide as an oxidizer, they can be made fairly portable, so banning large amounts of ammonium perchlorate isn't going to stop, or even deter a determined anti-aircraft missileer.

Look, Rand: the whole thing is so ridiculous anyway. If I was a terrorist hoping to take out an airliner (not that I amm or ever would be. The only way I'd ever do something like this is if the increasingly fascist government pushes me to armed insurrection, in which case I'd be after military targets), I wouldn't fool with trying to fabricate my own missile. I'd buy a set of nid-sized R/C airplane model kits. put a small explosive payload on each, and add a very primative (relitive to any track/guide system you could put together for a missile), acoustic-based track/guide system that knows left from right and the airliner's expected glide path.I unlesh my twin angels of death on the next approching 777 and observe as they do a simultainous Canada Goose routine on each turbo-fan's intakes.

Trying to regulate APCP by requiring High Power rocketeers to get a Low Explosive User Permit will substantially increase the number of LEUP's that the BATFE has to process and track. One can also legally buy lots more than just APCP when you hold an LEUP, so the action of the BATFE could potentially end up increasing the amount of Real explosives (which APCP is not) in the hands of the public. I think the real reason for the action is that BATFE is acting like a typical bureacracy - trying to extend its authority, budget and staff. Rocket engines are actually still exempted from BATFE oversight by 27 CFR 55.141-a-8 since they are "propellant actuated devices", an officially acknowledged position of the ATF up to about 10 years ago. The question where this exemption was discussed was taken out of their Q&A document about 3 years ago - after amateur rocketry became a target - even though the PAD exemption hadn't changed. Attempts by the ATF to illegally regulate these rocket motors is the subject of a federal lawsuit filed in 2000 by a couple of amateur rocketry groups. Still no judgment.

Saying APCP is an explosive is like calling dry ice an explosive since I could put it in a sealed soda bottle. APCP is purposely designed to burn without exploding (unlike black powder, which has a high burn rate coupled with a high pressure coefficient - used in the Estes engines and fireworks) or detonating - even when promoted with a blasting cap or det cord (unlike TNT, a true high explosive. If anything, APCP is a little too difficult to ignite and doesn't burn fast enough. I think the fact that the ATF is trying to regulate something that is actually safer than the alternative tells you that the safety of the public isn't their real motivation. Flying these rockets is already well-regulated by the FAA and amateur rocketry has an exceptional history of safety. Contrast it to the number of people hurt each year by Radio Controlled model airplanes, for instance.

I agree 90% with Brad Hitch.

Black powder is not an explosive as tested. Only classified as an explosive for "DOT shipping purposes". 1.1D. However a blasting cap will not set it off. It will not sympathetically detonate or for that matter detonate at all. It deflagrates.

Furthermore this poster made a mistake in that BP has a LOW pressure exponent. It burns at close to the same burning rate at a wide range of pressures. That is one of the reasons it is so suitable to small model rocket motors as well as 12 inch guns.

Ya Know. All the Libs and Dems wanted to move to Canada because George W won the election. I got a question, Does Canada regulate APCP the way the US is trying to ban it? If not, I'm moving too, eh...

You know if a terrorist wants to target an aircraft, he is not going to use a ground based rocket (or even one hundred for that matter). That would be foolish as rockets have no guidance. If he were to engineer guided missiles, again that would be a waste of time and resources on his part.

To knock out an aircraft is much, much simpler than that. All the terrorist has to do is use an assault weapon and target the turbojets on an aircraft approaching an airport for landing. Hot lead will shatter the turbine blades akin to Kevin Connors' Canadian Goose (Kevin, KISS. Keep it simple stupid). And aircraft, on approach, are very vunerable as they haven't any altitude for evasive manouevers.

Since George Bush and Congress have allowed the Firearms Act expire, once again, the terrorists can easily obtain semi automatic assault weapons, convert them to automatics, and have at it. But instead of concentrating on the real threats, BATFE is concentrating on this amateur rocketry hobby and wasting the resources that they could be using to run extensive background checks on people buying weapons.

Do you feel safe? Really now, do you feel any safer than before 911? When politics (Republicans are pro guns and so am I pro gun) gets in the way of common sense, then you get the unreasonable laws as a consequence. GW Bush and Congress do not want to upset the NRA (National Rifle Association). They can't, that would be political suicide. So they'll screw with the technogeeks, like us, who design, build, and launch model rockets.

The easiest way to make sure that terrorists don't hijack another airliner is to arm all of the passengers to the hilt. Any raghead who would be insane enough to try to hijack the airliner would be shot. When they banned firearms in the late sixties or early seventies in the passenger cabin of airliners, the amount of hijackings increased. I mean this...Do you feel safe? I'd feel much safer if I were allowed to bring my 357 Magnum onboard the airliner. (I won't because it is unlawful. But, of course, I will no longer fly on commercial airliners. Take away one liberty, the consequence is that you take all of them away. And not only does rocketry suffer, so does the aerospace industry as a whole.)

Do you really feel safe? Common sense versus politics. I mean, personally I wouldn't think twice about icing someone who is going to attempt to kill thousands and/or me. If they don't value human life, then they don't deserve their own human life. And I value life...yours...mine because it is a God given gift. God bless you and may the good Lord Jesus Christ bless America.