MTA launch event, 2018-08-18

The RRS had a small event at our private Mojave Test Area (MTA) on August 18, 2018, to allow Richard Garcia to test his liquid rocket motor. Richard built a pressure-fed, 1000-lbf kerosene-LOX motor including all of the static fire test stand equipment and control valves.

desert morning at the MTA

Richard Garcia reviews his list in the MTA blockhouse

Switch panel and electrical cabling

Richard had spent a good part of Friday and early Saturday getting his test stand mounted and ready. He had made arrangements to share the contents of a liquid oxygen dewar to supply the oxidizer he needed for his test with other RRS member, Sam Austin. Sam was also preparing to fire his liquid rocket motor at the Friends of Amateur Rocketry (FAR) site just south of the RRS MTA on this same day. Arriving early in the morning, I was glad to help Richard with the final preparations at the RRS MTA to start the initial checkouts and ultimately a successful hot-fire test.

Richard checks the wiring and pneumatic line connections

Richard’s 1000 lbf kerosene/LOX motor was designed for a chamber pressure of 300 psig and used a pintle-type of injector with an ablative lined chamber and graphite nozzle.

Richard Garcia tests both flow paths of his pintle injector in water flow

Ablative liner, G10, sits inside the combustion chamber of Richard Garcia’s 1000 lbf kerosene-LOX liquid rocket motor

Graphite nozzle within the chamber assembly of 1000 lbf kerosene-LOX motor

He brought his motor hardware to the January 2018 meeting, but now it was finally time to prove his design with a hot-fire test.

Richard shows his liquid rocket motor at the January 2018 meeting

Richard’s test used a high pressure nitrogen bottle to pressurize his propellant tanks, the left one for liquid oxygen (LOX) and the right one for kerosene. This regulated inert gas source also provided pneumatic pressure for the propellant valve actuators.

Richard’s static fire tanks and equipment mounted and ready for test, 2018-08-18

The top half of the thrust stand with the tanks and valves is fixed to the structure. The engine is suspended below and is secured to a plate which was mounted to an S-type load cell. These devices are an affordable means of measuring both compressive and tensile forces by the internal strain gauges built into them.

An S-type load cell used for thrust measurements in the static fire equipment

Caution was taken to keep the motor clean during handling and installation by caps on the ports and closing off the nozzle with aluminum foil.

View of Richard’s 1000-lbf motor from below; aluminum foil covering the nozzle exit to prevent foreign object debris (FOD) in the injector

With the validation testing complete and all valves are working, fuel was loaded, then preparations to load the cryogenic liquid oxygen (photo courtesy of Rick Maschek of FAR)

Careful review of the firing procedure before getting down to testing

Preparing for LOX transfer (photo courtesy of Rick Maschek of FAR)

All propellants loaded, everyone in the blockhouse, running the final checks before starting the countdown (photo courtesy of Rick Maschek of FAR)

The view from the blockhouse, a nice clean start of the liquid motor (photo courtesy of Rick Maschek of FAR)

Another view of the rocket firing from Richard’s tripod-mounted camera, 2018-08-18

A few seconds later with the dust kicking up from the motor firing, 2018-08-18

Closeup view of the rocket firing from a small mounted camera; it blew over from the firing but capture this image

Most of the testing seemed to work well. The motor had a clean start and stable run time for the full 5 seconds duration that Richard had predicted. Post-test inspection showed the engine to be in very good condition.

A view from up the nozzle after hot-fire; all looks good

Surface of the 1-inch thick steel plate was melted from the impinging plume; perhaps we’ll mount the next engine a bit higher

Tank pressure measurements were able to be recorded, however the thrust and chamber pressure (Pc) measurements were corrupted. Richard is working on downloading the hot-fire video to be posted on the RRS YouTube channel.

Soon he’ll disassemble the injector and chamber to see if the motor can be fired again. This was a great success for the RRS and we hope this to be the start of several liquid motor hot-fire tests as the RRS continues to improve on this powerful type of rocket.

Richard Garcia stands next to his 1000-lbf kerosene-LOX liquid rocket motor at the RRS MTA, 2018-08-18

I hope that Richard will be able to present his results at the next RRS monthly meeting on the 2nd Friday of the month. The next RRS meeting will be Friday, September 14, 2018 at the Ken Nakaoka Community Center in Gardena, California.

The RRS would also like to thank Mark Holthaus and Rick Maschek of FAR for their assistance on this test.

***

August 2018 meeting

The Reaction Research Society (RRS) held it’s monthly meeting on August 10, 2018 at the Ken Nakaoka Community Center. We were very well attended with four new people including returning member, Jim French. I was unable to attend the meeting, but other council members gave me their notes.

The RRS meeting got a late start at 8:00pm. (Our starting time is supposed to be 7:30pm.) The agenda items were not covered in order, but the list of topics to be covered were as follows:

[1]
This was to be a discussion of the 2018-07-21 launch event that the RRS held at the MTA with LAPD CSP and the student group at Watts. The event was successful with both the student alpha launches and a few RRS member alphas with payloads. The event was summarized in a previous article. A few things could have been done better which will make future events go more smoothly.

[+] A single, simpler briefing to the kids would have been more effective. The kids in the student classes do pay attention at the events (which is great) but the RRS is giving a lot of redundant information and a more concise presentation delivered by only the pyro-op will be far better than having three people talking at the same time.

[+] Also, every person conducting a launch or hot-firing at the MTA must submit a detailed proposal to the pyro-op for review at least a week in advance and gain the RRS and pyro-op’s approval PRIOR to coming to the event. The RRS used to be even more stringent on this requirement. The use of the RRS standard record form is required to be filled out by the experimenter for review by the pyro-op. The RRS requires advance preparation and there is no reason why this can not be done by all participants.

In recent times, our pyro-ops have been very casual about this requirement and have been kind enough to review things on the spot, but this was always at the pyro-op’s discretion. The pyro-op is the single and solo authority for what is and isn’t done at the launch event. The pyro-op should be the most informed individual about what is going to be attempted at the MTA.

The RRS has a Standard Record Form available on this website under the Membership tab of the Homepage and under the subheading of Forms. This downloadable document gives members a basic framework for the detailed information they must provide to the pyro-op describing their project and its goals. The RRS encourages members to present their proposed projects at the meetings and be very detailed in any reports submitted to the pyro-op and RRS president. The RRS wishes to keep good records to benefit the society and future projects.

RRS – Membership / Forms / Standard Record Form

[+] In future events where we have the student launch event conducted first, we should not plan nor conduct any events before the student launch. Getting back to an earlier point, having launch and hot-fire events declared, reviewed and scheduled days in advance will help make RRS events go more smoothly and safely. Years of experience at the MTA has shown that tasks ALWAYS take longer than planned and too much waiting can make coordination of large groups unnecessarily difficult. Therefore, having our coordinated events go off first without distractions from other planned activities will make it easier for our pyro-ops to conduct their duties and make our participants be more organized in their projects.

[+] The extreme heat of mid-July made it very difficult to conduct operations but having the motorized cart to shuttle the pyro-ops to and from the launch site made a critical difference. Bringing ice in the summer is a necessity. Having everyone well prepared for the hot weather continues to be the best advice.

[2]
Chris Kobel who is a member of Rocketry Organization of California (ROC) shared some advice for pyrotechnic operators (pyro-op). Chris has been a pyro-op for over 10 years and is pretty active with amateur rocketry. Safety was the primary emphasis of his presentation. He also mentioned a key point of contact at the Office of the State Fire Marshall (OSFM) of California, Tom Campbell. Mr. Campbell is very important authority at the California State Fire Marshall’s office who can answer important questions. Chris and the other pyro-op members at ROC were also willing to counsel RRS members interested in becoming pyro-op’s.

The RRS was glad to have Chris give our membership a wealth of information. We look forward to working more with Chris and ROC in the near future as the RRS is expanding our roster of pyro-ops for our growing events.

[3]
Osvaldo’s flight telemetry from his alpha flight on 2018-07-21 was briefly mentioned at the meeting. It was good that the flight was successful that data was taken. Given the time constraints, he’ll give more details at the next month’s meeting.

[4]
Progress on the RRS alpha parachute systems and future attempts was to be detailed by both Osvaldo and Larry who each attempted a unique recovery system built into the small confines of the alpha payload tube. Again, insufficient time was available at this meeting and this event can move to next month.

[5]
Sam Austin gave a presentation of MIT’s solid rocket launch and his upcoming liquid rocket hot-fire. Sam is here in Los Angeles for the summer on his internship, but managed to find time to launch his rocket from the FAR site on the same day the RRS held our launch event on 2018-07-21. The MIT team’s custom-built solid rocket motor (O4000) made from scratch reached an altitude of 33,132 feet as confirmed by dual altimeters. The vehicle weighed 121 lbm at liftoff and reached a peak velocity of Mach 1.8.

MIT’s rocket launch from FAR on 2018-07-21

MIT team poses with their rocket, 2018-07-21

Sam described a rough order of operations for their solid rocket grain making process and detailed their recovery. The rocket touched down safely 2 miles away and was fully recovered. The MIT team was elated and attributes their successful launch to careful design, many hours of testing that went into every component. The RRS is happy for MIT’s success and hopes they will test at the MTA with their next rocket.

[6]
There will be a liquid rocket hot fire testing on August 18th at both the Friends of Amateur Rocketry (FAR) site and the RRS MTA. Sam Austin has been working on his liquid rocket motor to test at FAR, next door to the RRS MTA site. Richard Garcia has built a small liquid motor for what could become the RRS standard liquid rocket design. Our two members have agreed to share resources and the hot fire events will take place on 2018-08-18.

Both projects will use a nitrogen K-bottle as their pressurization source and will share a liquid oxygen dewar to provide the oxidizer to both of their engines. Richard’s and Sam’s liquid rocket motors will use kerosene as a fuel. Richard’s design is a 1000-lbf thrust design with an assumed chamber pressure of 300 psig.

Sam and Richard have put a lot of work into these projects and we hope they have success. I plan to go out there to help document the event for a new posting to come shortly after.

[7]
The meeting was to discuss upcoming RRS launch events including the next one with LAPD. Frank has said that the next event with the LAPD CSP will be with the Boys and Girls Club. LAPD CSP is also working on setting up another school group in Watts for an RRS event. Specific dates were not yet set, but that information will be coming soon. We will post announcements of forthcoming launch events in the “Forum” section of this webpage.

[8]
RRS Instagram and YouTube account guidelines have been generated by RRS treasurer, Chris Lujan, and are now being reviewed by the RRS executive council. The idea of creating an RRS media manager position was proposed and accepted by the council. The RRS is considering offering this new position to RRS members, Bill Janczewski and Alastair Martin, who both have put forth a great deal of excellent work for the society. The RRS executive council will vote soon to better our social media presence to help our outreach efforts and give our followers a better view into the society.

Richard Garcia shared access information with the executive council on the existing social media accounts that the RRS has including Facebook and YouTube.

The RRS executive council now has access to Instagram and will be sharing photos from events more easily and quickly with our public audience. I have already begun to load photos I’ve had from recent events. More of the RRS will be posting to Instagram very soon.

Subjects not on the agenda included:

[BONUS 1]
The RRS will start to hold special Saturday morning seminars for special topics that can be covered in more depth outside of our monthly meeting. These bi-monthly sessions will take some work to coordinate, but should allow more of our membership to enjoy the quality of talks that we have been privileged to enjoy. Jim French agreed to give the first of the RRS Saturday seminars at a date to be determined very soon. Jim was a member of the RRS 25 years ago and we’re happy he’s come back to join us.

book by RRS member, Jim French

James R. “Jim” French also has the distinction of being a rocket engineer for over 60 years and worked at TRW on the Apollo program. He wrote a book about his experiences called “Firing a Rocket”. This first RRS Saturday seminar will be a great presentation to start this series. The date will be announced soon.

[BONUS 2]
I have been able to get the top and bottom plates made for the RRS ballistic evaluation motor (BEM) which will be a key part of the SuperDosa project and the RRS having the ability to take accurate burn rate measurements at the MTA for future motors. I am thankful to Matt Moffitt of CNC Specialty Machining in Huntington Beach. I hope to have the cylinder piece in the RRS BEM machined soon. This will likely require lathe work. Osvaldo is also looking into getting this part made. It is my hope the RRS BEM can be completed by the next quarterly update of the SuperDosa project in October 2018.

Top and bottom plates for the RRS BEM just back from the mill.

I have heard that Jack Oswald is trying to get into testing his large solid motor with an improved design. The RRS may have more to present next month on this subject.

[BONUS 3]
I wanted to bring a special device I bought from Additive Aerospace called a fly-away rail guide. I was introduced to this device by David Reese of ROC. Although the RRS has a very effective box-type rail launcher at the MTA site which will remain our standard technique, I decided to attempt a new method of launching an alpha just to get a longer guided path on launch.

Additive Aerospace – fly-away rail guides

This device allows a rocket to be fired from a extruded aluminum rail launcher such as the one we have at the RRS MTA, but without having to permanently attach the round launch buttons to the rocket itself. A spring-loaded clampshell piece goes around the rocket with a launch button on either side such that the clamp is closed when the rocket is on the rail. As the rocket takes off, the fly-away rail guide goes with the rocket along the rail launcher until the buttons clear the rail and swing open releasing it from the rocket as it speeds away.

Fly-away rail guide from Additive Aerospace; custom-built for an RRS standard alpha rocket, shown in the open position.

These devices are intended for common model rockets of the standard metric sizes (38mm, 54mm, 76mm, 98mm). I had this rail guide customized to fit an RRS standard alpha rocket which is slightly smaller than the 38mm size at 1.25 inches in diameter. I hope to demonstrate the fly-away rail guide device with a loaded RRS alpha from the 12-foot rail launcher at the RRS at the next event. I will relay my findings to the society and back to Additive Aerospace who is very interested to see how their design can work with the RRS micrograin rockets.

[IN CLOSING}

Meeting adjourned at 9:16pm which isn’t too bad. Our hosts at the Ken Nakaoka Community Center continue to graciously allow us to finish up despite the center’s closing at 9:00pm on Fridays. The RRS should seek to better finish on time as the staff at the center need to go home.

The next meeting of the RRS will be held on September 14, 2018.

For questions, contact the RRS treasurer, Chris Lujan.
treasurer@rrs.org

July 2018 meeting

The RRS held its monthly meeting on July 13, 2018 at the Ken Nakaoka Community Center in Gardena. We got a late start (7:45pm), but we were very well attended. New member, Wilbur Owens, brought a friend of his from the Compton Aviation Museum. The RRS accepted a new student member, Bill Behenna. We also had two newcomers from Caltech stop by who were interested in stromectol drug joining the society.

Our July 2018 meeting gets started

We welcomed our newcomers and started our meeting with a very full agenda. Frank brought a new air launcher device he built which operates by a hand piston. We didn’t have time to discuss it but Frank is adding more teaching tools to our educational program to show how much fun even simple rocketry can be.

Frank’s hand pump air rocket launcher

We went a little out of order from the agenda, but we managed to cover all topics in this meeting that ran very late.

[1]
The first topic of the agenda was to confirm to everyone that the next launch event at the MTA will be on July 21st. We will host a new group of students completing the RRS educational program. This is another fine group of students from the Watts area and we are grateful to the LAPD CSP program for their continued support of this recurring and successful project. Frank and Larry noted that we will try to get this event started earlier to attempt to avoid the scorching heat of mid-day.

Also, we had a discussion about how to improve the society communications in the wake of a last minute unforeseen change of schedule for a launch event. This was an exceptional case and unlikely to happen again soon, but it did highlight an important aspect of RRS operations which is communicating with our membership. It is very, very important that all active members have their emails with the RRS secretary as the duty to send out the mass email falls to me. There are two ways that the RRS secretary communicates to our active membership:

    (1) the email list for meeting agenda notices

I have been building this email list and maintaining it, but I know that I am missing some interested parties. The communication between our membership is still important. Please be kind to other members and pass on the notices and encourage everyone not receiving their emails to let me know to make the proper inclusions. This is a constant work in progress and get xanax I am thankful to those who help make this happen.

    (2) posting of all launch event dates is on the RRS website

I regularly update the launch date information under the “Forum” section of the RRS website under the “Launches” tab. Modifications to the RRS.ORG website were discussed as a means to make a clearer way for anyone to see if we are “GO” or “NO-GO” before the launch event. I’m not sure what Chris Lujan has in mind, but we will discuss this issue further as time goes on. Effective communication to our membership is important. The use of other social media platforms like Twitter or Facebook were suggested, but it is not clear how widely used these platforms are with our membership that spans many generations of technology adoption.

[2]
The second topic from the agenda was my proposal for the RRS to acquire a road sign. This has been approved by the society and the cost is not unreasonable. Placement of a simple sign at the first gate leading into the RRS’s private testing site, the Mojave Test Area (MTA), will make it easier for newcomers to be sure they are going directly to our site adjacent to the Friends of Amateur Rocketry (FAR).

RRS sign at the MTA entrance

The RRS does have a great sign built on top of a metal arch right at the entrance to the MTA built by member, George Garboden, but the society felt a second smaller sign (24 inches tall by 36 inches wide) at the first gate would be another helpful feature to show newcomers the way in.

Proposed road sign for outside the first gate to the RRS MTA

Placement of the sign will be about 10 feet behind the barbed wire fence about 6 feet to the left of our larger metal gate. This should assure good visibility to those reaching this fork in the road.

We had a substantial discussion about the sign content. The results of this discussion are in the sample posted from the website. We also had a substantial discussion about mounting of the sign and the desire to have a solid structure that can withstand years of the gusting winds of the Mojave. The sign quality chosen was of the highest quality to assure a long life under the corrosive effects of Koehn Dry Lake. Richard has suggested that the sign include the RRS logo which I will look into with the vendor. The RRS has given the authority to proceed on this task.

Further to this subject, Richard Garcia has suggested the sign be accompanied by some kind of metal sculpture representing a rocket. This would nicely complement the sign, but this is a topic beyond the original scope of the meeting. In times past, George Dosa had a large metal pipe embedded vertically into the dirt which used to have fins on it like a rocket reaching the end of its ballistic flight. I think the pipe is still there but the fin decorations have been long removed.

[3]
The subject of Saturday seminars was only briefly discussed at the July meeting. In past meetings, the RRS has had special presentations made by invited guests. These are very enjoyable to our membership, but they do often run long and consume a lot of meeting time. To be more effective in our meetings, it was recommended that for lengthy presentations, the society ought to schedule a special meeting for our membership on a Saturday morning at the Ken Nakaoka Community Center in Gardena. This way, those of us with day jobs can come to the center before the heat of the day and enjoy the presentations at our leisure. The RRS has identified several potential candidates for these “Saturday seminars”, but thus far, the first session has yet to be scheduled. We will revisit this topic in later meetings. Our vice-president, Frank Miuccio, will be the point of contact on this topic going forward. Updates on this topic will be posted on this website.

[4]
The RRS director of research, Richard Garcia, discussed his progress with the RRS standard liquid rocket. This has been garnering a lot of enthusiasm as many universities have been pursuing similar goals.

RRS director of research, Richard Garcia, explains his liquid rocket prototype at the 75th anniversary symposium

The RRS has decades of experience in building these powerful but simplified launchers, but in recent times our activity in this area has been slight. Richard has made a lot of the key drawings, but is still working to finalize the dimensions and proceed with construction. The RRS membership at the meeting had the chance to review his current drawings and make suggestions. Richard will proceed with completing the design and drawings and with the RRS support begin with selection of suppliers, machinists and construction.

Richard’s rocket will use the RRS 15×15 rail launcher that we have at the MTA. The 16-foot rail length should be sufficient to guide the rocket to a stable initial flight. Further aerodynamic study will be needed to finalize the design. Preliminary pictures and features of the design will be discussed in future posts.

[5]
The next topic was the subject of pyrotechnic operators and the RRS’s mission to qualify more members as licensed pyro-op’s to expand our ability to conduct events and improve the knowledge of our membership in this important aspect of safety in operations. What we do can be very hazardous, but with the attention to detail and commitment to safety that we have shown over the decades of our history, we are blessed to not have ever had a fatality and very likely to continue this tradition long into the future.

The RRS has identified a few members including myself who are committed to starting the process of becoming a pyro-op with the California State Fire Marshal’s office. The first step is making a request to the Cal State Fire Marshal for their latest package of information which includes a PDF copy of the latest laws and regulations that every pyro-op is expected to know.

California State Fire Marshall rules on fireworks also governs amateur rocketry

In parallel, the RRS is creating a standard package of information for members that include these state provided materials and other resource materials deemed useful by the RRS to properly educate any current or aspiring pyro-op.

The second step in the process is getting five letters of recommendation from licensed pyro-ops of the same class or above the class level you are applying for. The first level of licensing is Rocket Class 3 which is what our new pyro-ops will seek. The final step is paying your exam fees to the state of California, sitting for the exam, passing the exam and getting your license information from the state. It is very important that our membership strive to keep their state license current and not let it lapse. The RRS is indebted to our pyro-ops for making a big part of what we do possible and safe.
https://metrowesthumanesociety.org/getting-lasix-without-prescription/
Letters of recommendation require a licensed pyro-op to vouch for your abilities to conduct safe operations and a demonstrate sufficient knowledge and competence in all relevant areas for rocketry all in a signed document sent to the state of California. It is not an easy thing to ask of someone who doesn’t know you well. It is not uncommon and very reasonable for many pyro-ops to refuse a request for a letter of recommendation. It is the requester’s sole duty to prove themselves to each licensed pyro-op that they are worthy of their endorsement.

In the past, the RRS had many pyro-ops and by attending MTA events and participating in meetings and other society events, RRS pyro-ops would get to know you and could more easily vouch for your skills to the state. Osvaldo has been successful in securing his letters of recommendation and sending his application to the state. He is now waiting for instructions on when to sit for his examination. This is a process that can take months.

I have also been fortunate to secure letters of recommendation from licensed pyro-ops, but I am still in the process of qualifying in the eyes of other pyro-ops I have asked for their endorsement. It was suggested that the new class of RRS pyro-ops combine our efforts and share our resources. It was also suggested that we ask some licensed pyro-ops to make a presentation at an RRS meeting or special event as a way of educating us in the practical knowledge that they have gained as a pyro-op. Perhaps through these sessions, more of our members can get the letters of recommendation necessary to begin the process.

Dave Nordling assists in the loading of an RRS alpha into the rails under the instruction of pyro-op, Dave Crisalli

It is my intent to encourage the RRS to adopt a more unified approach to gaining this knowledge either by seminar or by apprenticeships that could be offered by other rocketry groups such as Rocketry Organization of California (ROC). I took the action to approach ROC and other amateur rocketry groups about sending a set of our aspiring pyro-op members to a launch event or special training session in the hope to achieve wider endorsement and help build the RRS roster of pyro-ops.

[6]
As required since the start of the SuperDosa project, I presented my quarterly update.

To remind everyone what the SuperDosa project is, it is the society’s desire to retake the amateur rocketry altitude record lost in 2004 to CXST. At a height of 380,576 feet (116 km), this is a daunting challenge, but we have a substantial amount of knowledge and experience from our past members to drawn upon. Many boosted dart designs, similar to the SuperLoki or Viper III, are capable of reaching this altitude range above the von Karman line of 328,083 feet and 4 inches (100 km).

Boosted Dart – Viper IIIa

We have decided to begin a long process to build a boosted dart type of rocket and launch it from Spaceport America or Blackrock to retake the amateur rocketry altitude record by aiming for 400,000 feet (121.92 km). This will take several attempts and perhaps a few different designs, but eventually we will succeed.

For comparison, USC recently set an altitude record for a university built rocket of 144,000 feet (43.89 km).

Some of our newest RRS members just recently fired a full-scale solid motor at the MTA with the aim of reaching 150,000 feet (45.71 km).

The vehicle that succeeds in meeting this challenge and restoring the RRS title will be named after long-time member and a mentor to many in the RRS, George Dosa. George was the first licensed pyro-op in California for rocketry and wrote large portions of the rules governing our hobby. George is still active with the society and we are showing our gratitude by using his name for this project.

SuperDosa-mockup (2)

George Dosa at the 75th RRS symposium in April 2018, third from left

Substantial progress has been made by Larry Hoffing in making sample batches of the RRS standard recipe, although I understand he had to make some deviations to the mixture due to lack of particular chemicals necessary for plasticizing and release from the mold. Addition of accelerants such as iron oxide is not necessarily part of the RRS standard mixture, but it has been used in other mixtures to increase burn rate with good results. The RRS is in the process of re-establishing suppliers for the key materials such as the HTPB binder and the ammonium perchlorate and aluminum powder of different sieve sizes.

Substantial progress has been made with some of our new members and their booster design which was unsuccessfully tested on June 7, 2018 at the MTA. The mixing procedure and some of the equipment necessary for casting larger grains will surely be useful in this sustained effort to build motor of this size. Part of the issue was poor subscale testing to get burn rate data.

The RRS is working on completing a ballistic evaluation motor (BEM) to attain proper propellant curve data which should benefit all society projects using the same solid mixture. I have not had any luck with the getting our top and bottom plate assemblies yet, but I hope my machinist will be available soon to complete all parts well before the next quarterly update.

RRS ballistic evaluation motor design concept

Some of the parts are ready. Richard Garcia was kind enough to turn out the initial set of nozzle pucks of variable throat sizes. I have the fasteners and gasket materials which need to be cut for the seals. The RRS has a 5000 psig pressure transducer and some of the fittings, but we need a short length of clean stainless steel tubing to make the pressure connection. We have a data acquisition unit, but the wiring harnesses needed to be made to route back to the blockhouse.

Chris Lujan has recommended that instead of bringing someone’s personal laptop we get a simple computer like a Raspberry Pi unit to do the data crunching and output the results. The desert environment can be very damaging and it would only take a simple computer to manage the data and output the results. Chris will work on this hardware and software aspect of the data acquisition and processing.

RRS BEM graphite nozzle pucks, courtesy of Richard Garcia

More progress on the SuperDosa progress will be presented in October at the next quarterly report.

[7]
The next topic of discussion was led by Alastair Martin. Alastair is a very active member of the RRS and the Mars Society. He is a filmmaker and producer and brings many talents to the society.

Alastair Martin records elements of Richard Garcia’s rocket candy propellant manufacturing process at the RRS MTA, 4/7/2018

Alastair discussed the necessity of the RRS embracing a larger social media presence. The benefits are that the RRS can reach a wider audience, particularly in the younger demographics. Alastair recommended that the RRS open an Instagram account and do work on improving our Facebook page that is already online. Although there are other social media platforms, it was these two services that he has the most success in his businesses.

The use of Instagram can make the society better able to show the world a glimpse of our activities from a select group of our active membership. Instagram is useful for conveniently and frequently posting photos and short videos and is virtually instantaneous. This nicely complements the website we currently use. The RRS approved the opening of an Instagram account.

Once you have the Instagram smartphone app loaded, you can find us at our Instagram ID which is our full name without spaces:
Reactionresearchsociety

Our society treasurer, Chris Lujan, generated the account and he will be primarily responsible for the RRS Instagram account. The executive council, director of research and events coordinator will be the first members to have permission to post photos to the RRS Instagram feed. The RRS will consider allowing other trusted members to post on our new Instagram account as we go on.

Reaction Research Society on Instagram

The RRS has a Facebook page. I think it is our vice-president Frank Miuccio, that maintains this site. The RRS will strive to post more often on Facebook which is widely used by many people worldwide.

RRS on Facebook

As secretary, I will continue to maintain our world-wide web site, RRS.ORG as our primary means of advertising ourselves and posting updates to activities.

[8]
After some debate and discussion, the RRS has decided to proceed with holding the 2019 RRS symposium in April next year. Although it is a substantial commitment of resources and money by the society, the 2017 and our 75th anniversary symposium were successively larger hits with our public audience. We will strive to improve our symposium based on the lessons we’ve learned and use the momentum of enthusiasm built from two very successful events. However, it was agreed that after the 2019 RRS symposium, the society will not hold another for two years. Our commitment to what will be the 2021 symposium will be pending until the year before.

The 2019 RRS symposium is coming in April.

With this decision, setting the date and starting our long process of contacting industry, academia and government speakers will begin. There will be more discussed on this topic in future meetings. We are excited to confirm another symposium and hope to make this event even better than before.

[9]
The agenda had originally stated that our next launch event at the MTA with LAPD CSP will be Saturday, July 21st. We circled back to this topic reminding everyone that the safety briefing will be conducted at 10:30 AM and the launch event will proceed at 11:00 AM. It is the goal to have all eight of the standard alphas assembled by the students launched before the heat of the noon-day sun rises. We want to encourage our membership and invited guests to this event to arrive very early which for me means leaving Los Angeles at least before 7:00 AM. Dave Crisalli will be our pyro-op for this event and I have volunteered to be his apprentice unless one of our other pyro-ops in training would like to do so.

[10]
I had an agenda item to discuss future events at the MTA including one possible event with a BBC program in the UK. This may occur in October 2018 and discussions are still in work. The RRS will likely hold another educational event with the LAPD CSP in the fall which may be able to coincide. Larry had made contact with the Girl Scouts of Orange County who were seeking the RRS to participate in a regional STEM event. All of these projects will also be discussed further at the next meeting in August 2018 as more information comes in.

[11]
Osvaldo gave our meeting audience a demonstrate of his new method of loading micrograin propellant (without the propellant of course). For some background, the RRS standard alpha is a common platform in our society events. They are particularly common with our educational classes that we hold regularly. Based on the micrograin propellant invented by our founder, George James, this simple mixture of zinc and sulfur powders presents a challenge in loading. The coupler is installed with an O-ring seal at the head end. The 3-foot long, 1.25-inch DOM steel tube with four welded sheet metal fins and holes drilled for installing the nozzle is basically an open tube closed at one end.

alpha bulkhead loaded and bolted in

RRS standard alpha configured for propellant loading; nozzle is installed at the end of loading

The 80% zinc and 20% sulfur by weight propellants are premixed by tumbling and is loaded into the propellant tube by hand. Entrapped air is a frustrating factor in getting a tight packing of the propellant into the tube. As the powder falls to the bottom, the air can not completely get out of the way and empty pockets form. These pockets can be released by simple mechanical tapping or gently bouncing the tube vertically on a wooden block. In the finite volume of the propellant tube, entrapped air is a waste of space that could be filled with the mass of propellant. The loaded weight of the alpha subtracted from the empty weight of the alpha propellant tube at the start is the only real gauge of how well packed the propellant is.

Many methods of compaction and casting of the micrograin propellant to achieve higher densities have been tried over the RRS history. Some of these have had success, most did not. This topic is a long subject which can be researched and summarized in a separate article if there is sufficient interest. For now, only the simple method of manually loading the premixed powder will be discussed.

The common method used today is to pour in the propellant mixture one cup at a time and bounce the bottom of the tube on a wooden beam. Vibration devices do work, but they tend to work too well in that the zinc and sulfur being of different densities start to separate which is very undesirable. This method of one cup at a time is slow, but effective.

a cupful of micrograin propellant drawn from the tumbling mixing drum

traditional loading method that carefully removes trapped air by periodic mechanical tapping is very slow and very messy

When the RRS started to run more launch events with schools, loading a dozen or more propellant tubes started to take a great deal of time including coming to the MTA on the night before. Osvaldo who is the main person doing this loading sought a faster but effective means to loading.

He tried a few experimental practices including drawing a vacuum at the bottom of the tube with a special fitting and using a lowered piston on a string approach, both of which were flawed and not that successful.

His most recent method has proven to be very effective and quick. He gets a length of tiny brass tubing and loosely affixes a round cardboard disk. With this cardboard disk inserted into the mouth of the tube and a proper funnel attached, the full propellant load of the alpha can be loaded directly into the funnel.

Rapid micrograin loading by small brass tube and cardboard disk

By allowing the weight of the full propellant load to lower itself into the tube on top of the cardboard disk, the disk serves as a seal to divert any entrapped air beneath up through the hole in the brass tube. The air below the solid powder mass has a route to escape through the hollow tube up the center. With this technique the whole propellant load can drop into the tube in one motion, leaving the cardboard disk at the bottom. The brass tube easily pulls out from the cardboard disk and out of the propellant tube now loaded with the micrograin propellant.

tube and cardboard disk aligned in the funnel in the mouth of an empty RRS alpha propellant tube

Illustration of rapid method of loading micrograin propellant

This technique eliminates the barrier of the air below trying to move past the falling mass of powder and results in a reasonably dense packing of the propellant all done in one shot.

Osvaldo Tarditti and his rapid method of micrograin loading; note the very small but long brass tubing and the extra large funnel to hold the full ~4 lb load of micrograin propellant

I took photos of Osvaldo’s process at the last launch event with UCLA on June 2, 2018. The pictures and illustrations I have posted of the technique that has been successfully demonstrated at the MTA are hopefully clear enough to show the principle.
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[12]
This was intended to the first topic, but Osvaldo circled back it at the end. Osvaldo successfully flew a parachute system in an RRS alpha. This is a feat that I don’t think has been in done in a very, very long time. Most of our alpha rockets come back ballistically and require back-breaking extraction by shoveling out of the hard-packed dry lake bed. It has been a general goal of the RRS to encourage more payloads to be flown in the RRS standard alphas as we do a lot of these flights. It has been a goal of mine to eventually fly a parachute system in the tight confines of the alpha’s payload tube. Osvaldo developed a pull switch that activates a timer chip inside to delay the firing of a small powder charge that ejects the parachute by means of a rising piston. This was discussed in the details of the same launch event with UCLA on June 2, 2018.

Osvaldo stands behind his RRS standard alpha parachute system successfully flown at the MTA on 6/2/2018

We did not have a lot of time to show all of the parts, but Osvaldo did mention that he will fly his parachute system again at the July 21, 2018 launch event with a modified timer design and break-wire system that is more compact. I may get Osvaldo to write a full detailed article on this subject in a future posting to come. This parachute system if proven to be repeatably effective may become a standard part of our RRS launch events with schools, but we must consider the added costs of producing them with standard costs we already charge for our RRS standard alpha. This is a really good topic and I’m sure we’ll be talking more about this in August.

[BONUS]
Richard Garcia treated us to a short video made by Microcosm back in 2001 with their experimental launch vehicle that did engine test at the RRS MTA. This dual-engine liquid rocket had thrust vector actuators and went through a successful hot-firing in the video.

Microcosm’s Scorpius-S-RM-20k vehicle test at the RRS MTA in 2001

The video showed the later rocket flight. We may post this on the RRS YouTube channel for everyone to see. It was a nice way to conclude our meeting with a rocket firing and flight.

[IN CLOSING]
We adjourned the meeting very late (well past 10:00 PM) which is only possible due to the kindness of our hosts at the Ken Nakaoka Community Center which closes at 9:00 PM. We are very grateful to them, but the RRS must strive to be more effective in our meetings to start on time and finish on time.

If there are any topics for next month’s meeting, please contact the RRS and make your suggestion. In the August meeting, we will likely discuss the July 21st launch and lessons learned from that event. We also have other https://cohlife.org/diflucan-online/ events planned for this fall.

The next RRS meeting will be August 10th.

If there is anything I have missed or misstated, please let me know.
secretary@rrs.org