June 18, 2003
Senator Orrin Hatch
104 Hart Senate Office Building
Washington, DC 20510
Dear Senator Hatch:
Let me introduce myself, I am an aerospace engineer who was worked continuously in this profession since 1972. I also wrote Senate bill S724 with Senator Enzi’s staff. My letter is in response to the letter sent to you by the Department of Justice on S724. I can speak on this subject with some authority as the inventor of four new rocket propellants for NASA and the Department of Defense, a principal engineer for the MX missile second stage (my signature is on the drawings), consultant to Thiokol on the redesign of the Space Shuttle solid rocket booster field and nozzle joint, inventor of powdered propellant rocket engines and jet engines, a pilot (flown single and multi-engine aircraft), engineer for air to air and ground to air tactical missiles, which included rewriting Air Force software for simulating missile and aircraft encounters, college instructor for classes on rocketry and small business owner.
I understand the dilemma faced by you and your fellow Senators on the committee when you have conflicting information from the rocketry community and the ATFE. First, it should be noted that the Department of Justice and ATFE are not recognized authorities on missile technology or rocket propellants. Competent government authorities on missile and propellant technologies would be the Air Force, Navy or Army. If you show them the letter from the Department of Justice, I suspect you will get howls of laughter. Let me tell you why.
There are two basic types of APCP, detonable and non-detonable. Detonable APCP is a high-energy propellant used solely in military rockets. The Trident missile uses a detonable APCP since the submarine tubes are limited in volume and the missile needs the maximum propulsive energy in that limited volume. All of the land based ICBMs from Minuteman to MX as well as the Space Shuttle boosters use a non-detonable version of APCP. The fact that this propellant does not explode was proved during the Challenger disaster. In that incident, the support strut holding one of the solid rocket boosters to the External Tank failed and the booster rotated into the External Tank. This resulted in a rupture of the tank causing oxygen and hydrogen to mix and explode. The two APCP solid rocket boosters flew through the explosion (one of the most powerful chemical explosions possible) without damage or exploding. Several seconds later, explosive charges were detonated on the outside of the two solid rocket boosters to rupture the rocket cases and shut down the engines. Neither solid rocket booster exploded, even with explosive charges detonating on their cases. But, the explosive resistance of non-detonable APCP goes beyond that incident. The MX missile, which also uses non-detonable APCP, is designed to survive a nuclear explosion as it leaves a missile silo. Even a nearby nuclear blast will not cause the APCP in an MX missile to explode.
The ATFE claims these propellants deflagrate and are therefore explosive. At one time, the ATFE's Assistant Director of Firearms, Explosives and Arson, John Malone, stated it is accepted by the ATFE that the speed of the burn front in materials that deflagrate is on the order of several meters per second. The solid rocket propellants covered in S724 burn between 5/1000th to 10/1000th of a meter per second. By ATFE standards, which they conveniently forgot in their letter to you, the propellant in S724 does not burn fast enough to deflagrate. The ATFE claims when APCP is confined it produces a powerful explosion. This is a distortion of the truth. The APCP does not explode, the container holding the APCP ruptures. When you blow up a balloon with too much air, the balloon ruptures with a loud noise. The air inside the balloon does not explode. God help us if it did, the ATFE would demand we all get permits in order to breathe.
One of the most outrageous claims by the ATFE is the use of rocket motors and materials to make anti-aircraft rockets to shoot down civilian and military aircraft. Now, I understand to someone who has not designed these types of rockets for a living, this could seem plausible. Let me assure you it is not possible. First, the rocket will go into a gravity turn when it is fired and arc over. While calculations could be made to account for this effect in aiming the rocket, the exact altitude and speed of the aircraft would have to be known. This could only be determined by sophisticated ground radar. Second, assuming this radar was available, the aircraft would have to maintain this precise speed and altitude after the rocket was fired. As a pilot I can tell you that will never happen, even on autopilot. Third, since the rocket is unguided any winds aloft the rocket encounters will throw it off course and cause it to miss the aircraft. There has never been a place or time in the United States when there were not winds aloft at constantly varying speeds. In short, the rocket will always miss the target.
The idea of a terrorist building a guided missile is also ridiculous. The sophistication required in the way of sensors, computers, software and control mechanisms is beyond the capability of everyone except a few companies in selected countries. The reasons why would fill more pages than in a book. However, ask yourself this question, if it were so easy, why does the Department of Defense spend a small fortune on each ground to air tactical missile? Not to mention the support equipment that goes with it. If some “yahoo” from the Middle East can build an anti-aircraft missile by ordering out of a hobby supply catalog, then the Senate should begin hearings as to why the Department of Defense is wasting money on contracts with Boeing, Lockheed Martin and others.
The ATFE really went over the top with their claim that hobby rockets could be made into “light anti-tank” weapons. I find it hard to believe that plastic nosecones and cardboard tubes are going to have much affect on armored vehicles. To do any damage, the rocket would have to have an explosive warhead. It is already necessary to have an ATFE permit to obtain the explosive for the warhead. S724 does not change that. As for the five-mile range, that is pure nonsense. A guided rocket fired horizontally from the shoulder will hit the ground in about two seconds with a hobby motor for a distance of about 1000 feet. To get longer range, the rocket would have to be guided so that it generates lift and “flies” to the target much like a TOW missile. If you think someone is going to put that together in their garage, then call the Army and ask them what one costs and how much effort it took to develop it. The idea of hobby rockets being used to make bombs and shooting down airplanes and destroying tanks goes beyond the limits of credibility and more into the realm of “Roadrunner” cartoons.
Terrorism is certainly a real threat, but we are not going to be effective in our fight against it by going after phantoms. Why try to shoot down an airplane with a rocket that will not work, when you can use a rifle that will work? Why try to make a bomb using a propellant that will not work, when you can make one out of smokeless powder that will work? None of those items require an ATFE permit.
Many people say it is a new world after 9/11. They are wrong. It is the same world that has always been with us. The politics of fear are not new. In 1930’s, it was economic fear. Franklin Roosevelt rose to the challenge and told Americans, “We have nothing to fear, but fear itself”. In the 1950’s, it was the fear of communism. Senator Joseph McCarthy from Wisconsin briefly turned that fear into a nightmare by encouraging Americans to wonder if their neighbors were communists. Today, it is the fear of terrorism. Now, Americans are being encouraged to wonder if their neighbors are terrorists. Are we going to pass legislation based on those irrational fears or are we going to accept the wisdom of Franklin Roosevelt, “We have nothing to fear, but fear itself”. I hope and pray it is the latter.
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