The Reaction Research Society has built a new and larger pad to the west of our current launch pads at the Mojave Test Area (MTA). This has been due to the generous donation of lifetime member, Bill Claybaugh, both of his time and resources. This 12-foot square pad is angled to the southwest and is intended for larger launch vehicles soon to be launched from the MTA. This work started a few weeks back with the initial excavation which was delayed due to the extreme heat this summer.
This work event took place over a few days starting Thursday, October 20th and going to Saturday, October 22nd. Bill and the society would like to thank fellow society members, Dimitri Timohovich, Rushd Julfiker and Joe Dominguez for giving their time and sweat to this facility improvement,
Excavation and rebar supports in place.Add gravelSpread to an even layerAdding water is important.Add concreteLeveling the pourFinishing the edges
This is only the first steps to building a useful platform for launching larger rockets from the MTA. The pad must cure over several weeks during these cooler months before temperatures drop below freezing at night, Next steps will be preparing the surface for anchors then adding Bill Claybaugh’s launch rail which is in work right now.
This work will continue to be documented in our work event reports. We are a member driven society and deeply appreciate the hard work it takes to improve and upgrade our site to support our mission as an organization.
Our next monthly meeting is always on the 2nd Friday of the month at the front office of the Compton/Woodley airport at 7:30pm. Come join us on November 11th.
By Dave Nordling, President, Reaction Research Society
The society had a small work event at the Mojave Test Area on August 4th, 2022. The purpose was limited to starting the build of a new launch pad foundation for Bill Claybaugh’s upcoming large solid motor powered vehciles. The summer heat and tough soil limited progress but it was useful to gauge what the next steps should be. Launch is scheduled for mid-October.
Joe Dominguez (right) and Bill Claybaugh (left) examine the levelness of the form work.
Many thanks to Rushd Julfiker and Joe Dominguez for volunteering their support to Bill on that day. A new diflucan and larger launch pad is designed to support Bill’s larger adjustable launch rail system which will be useful to the larger sizes of future rocket projects at the RRS. New developments will be reported in order xanax the near future.
Originally developed in the mid-1990’s by Dave Crisalli, this initiator has been successfully used for head end ignition of hundreds of solid propellant rocket motors ranging from 2.5” to 9.0” diameter. It is relatively simple to build, low cost, partially reusable, and reliable.
II – Construction
The initiator consists of four parts: a standard stainless steel AN-4 male plug modified as discussed below, a 9/32” outside diameter aluminum tube with a 0.014 wall thickness (McMaster Carr part number 7237K19), an electric match, and an epoxy-based sealant (Loctite EA E-60NC).
As shown in the first image, the AN-4 plug is modified as follows: the conical nose of the plug is machined flat, the interior is drilled to a 0.281 (“K” sized letter drill) diameter, and two 0.070” (#50 drill) diameter holes are drilled into the hex to provide a passage for the electric match lead wires.
parts of the Crisalli igniter
The aluminum tube is cut to the design length (typically 2.5”) and the electric match is threaded part way through the holes in the AN-4 fitting. Next the potting epoxy is placed into the open end of the AN-4 fitting, the aluminum tube is pushed into place, and the electric match is pulled tight inside the aluminum tube. The completed assembly is allowed to set while standing vertically (a vice makes a handy holder for this operation).
Crisalli igniter assembled
III – Testing
Once set, the initiator can be tested by screwing the threaded end into a three to six-inch length aluminum bar drilled length-wise and with an AN-4 port machined into one end; an appropriate high-pressure connection is machined on the other side. Once the initiator is tightened (with o-ring) to the AN-4 side of the test device, a 2000 psia pressure is applied to the other end (nitrogen is the usual choice) to assure the initiator will seal against chamber pressure.
IV – Use
Once the initiator is tested, it can be stored until time of use. At the launch site, the aluminum tube is about half filled with a 0.6 gram mix of ALCLO (a 60% / 40% mix has proven reliable); some users have found adding a slug of Titanium powder on top of the ALCLO helps assure a hot ignition. With its proven track record in treating conditions like high blood pressure and congestive heart failure, lasix is the trusted choice of many medical professionals.
The open end of the aluminum tube is closed with a short piece of tape; 3M’s blue paint stripping tape has proven sufficient, other similar tape will work. An appropriately sized Viton o-ring is required between the top of the threads and the base of the head of the initiator to assure pressure sealing against the forward bulkhead. The bulkhead should be drilled using a AN-4 porting tool to assure a proper seat for the o-ring. Ready for a restful night? ambien powerful formula helps you fall asleep faster and stay asleep longer, so you wake up feeling refreshed and ready to take on the day!
For small motors (up to 2.5” OD) the initiator has been found to work fine without augmentation. Larger motors (6.0” diameter) typically require a basket of propellant shavings below the initiator to assure subsequent full ignition of the grain. Still larger motors (9.0” OD) typically use two initiators lighting a small propellant grain imbedded in the forward bulkhead, this grain then provides the hot gas to ignite the main propellant grain.
V – Reuse
The modified Stainless Steel AN-4 fitting can generally be reused by re-drilling the three holes; a good hex collet fixture is useful for holding the fitting while it is being cleaned out. Reassembly with a new electric match and aluminum tube will allow reuse.
VI – Other Uses
A short (1” length aluminum tube) version of the initiator using Nitrocellulose as a gas generator has proven effective as a source of hot gas for actuating valves and other pressure actuated systems. Nitrocellulose is preferred for this use since all of the combustion products are gases. Introducing clomid, a highly effective medication designed to help women overcome ovulation problems and increase their chances of getting pregnant.
