June 2018 meeting

The RRS held its monthly meeting for June 2018 on Friday the 8th at the Ken Nakaoka Community Center in Gardena. We were well-attended but got a late start on the agenda items. Wilbur Owens came back to see us again and has decided to become a member. Mohammed Daya who has joined the RRS also was able to stop by before the meeting started just to say “hello”. We were also glad to have Sam Austin back in town. Sam is a student at MIT interning at SpaceX this summer. He also paid us a visit both at the MTA on June 2nd and at the meeting tonight to discuss the liquid motor he built. There was lots to talk about at this June meeting between our outreach events and the hot fire testing.

RRS discussing things before the June 2018 meeting starts

A lot to talk about at the June 2018 meeting

[1] The RRS event at the Two-Bit STEAM Circus in Hawthorne was quite a success. The RRS was a bit short-handed, but we have great volunteers that stayed busy the whole time. The air rocket launcher was one of the big hits at the Circus event and we have been invited back for the next event in September. Frank made some improvements to the paper rocket template that is cut, folded and secured with tape to make the narrow tubes with attaching fins that comprise a paper rocket for the pneumatic launchers we have. The build process can be challenging for some, but it always is satisfying to see the finished product fly. The RRS is glad to have these events and we will surely do more.

Here’s some photos that Osvaldo took at the event.

RRS at the Two-Bit Circus STEAM Carnival in Hawthorne, CA. Frank works with kids to make the paper rockets for the RRS air launcher.

The air launcher is made ready to fire a paper rocket.

On a side note to this topic, USC is having a CRASH STEAM Carnival in 2019. We were invited to attend this year’s carnival, but the RRS is shorthanded and couldn’t support. We hope to expand our society to be able to come out for more events across the great city of Los Angeles. We’ll have more information on this event later.

[2] UCLA held their launch event at the MTA on June 2nd. The event was two-fold, it was the final project for the UCLA rocket propulsion class taught by Dr. Spearrin. It was also an opportunity for the UCLA Rocket Project team to static fire their hybrid motor. The event was a success for the class with the winds being nearly calm for most of the day. The small hobby rockets with F-sized motors reached good heights without being carried too far by the winds. Each had an altimeter and a hard-boiled egg as a payload that had to be safely recovered. Most were successful, but others not so much. A full write-up was done on an earlier RRS posting.

RRS MTA launch event – 2018/06/02

As a further note, UCLA was using a Jolly Logic Altimeter 3 model in their hobby rockets. These devices used by UCLA have proven to be very reliable and easy to use. The RRS will acquire some of these to fly in the payload tube of an alpha rocket to see what heights we reach in this micrograin mainstay rocket of our society.

Jolly Logic Altimeter 3 – manufacturer’s site

After UCLA’s static firings of their hybrid motor, the RRS flew an alpha rocket with a parachute system. This is a first in a long time. Osvaldo’s design had a safety switch to engage the battery only when the rocket is loaded to prevent it from getting depleted in waiting for launch. The parachute system also had a pull pin to start the timer circuit when the rocket lifted out of the rails. Osvaldo did bring another prototype of the alpha parachute system to discuss its features at the meeting, but we didn’t have enough time.

Osvaldo’s parachute deployment circuit that fits in a standard alpha rocket

After the June 7 launch event at the MTA, Osvaldo managed to find an RRS standard beta launched by UCLA last year. Although the payload segment sheared off in the extraction process, the nozzle is the precious part that can be cleaned up and reused.

RRS standard beta recovered from the RRS MTA; payload segment was not recovered

Osvaldo was also kind enough to make the adapter piece necessary for testing the RRS standard alpha second-stage solid motor I designed in the horizontal thrust stand at the next event. With this simple doubled-ended adapter that goes in place of the nose cone, the second stage motors once finished can fit into the load cell adapter and the RRS can get thrust measurements. Chris Lujan is working on a sucrose-KN solid grain and Larry Hoffing is working on an AP/HTPB/Aluminum motor grain. I have done the preliminary calculations for both and pressures should be appropriate for the 1.75″ aluminum payload tube. More discussion on this topic in future posts.

RRS alpha second-stage load cell adapter piece for the horizontal thrust stand. It goes in place of the nose cone.

[3] The next RRS build event with the LAPD CSP officers will be with another group of kids in the Jordan Downs housing projects of Watts. We’ll get started next week, 6/15/18, and run six educational sessions on Friday’s and Saturday’s until the launch event at the end of the program at RRS MTA. This will take place on July 21, 2018. This had to be re-scheduled due to the extreme heat predicted for the original date of July 7th.

The students will paint and assemble a set of RRS standard alpha rockets. More alpha rockets means more fun for our guests and also more opportunities for our RRS members to try payloads. It’s my hope we can demonstrate another one of Osvaldo’s parachute systems and fly an altimeter chip if we can secure one in time.

Richard Garcia said that he already has an Eggtimer Quark chip which has an altimeter. I had the chance to meet Cris Erving of Eggtimer Rocketry at the last Rocketry Organization of California (ROC) launch event in Lucerne Valley on June 9, 2018. I hope we can get an altimeter payload ready to fly in a standard alpha payload tube by the July 7th launch.

Eggtimer Rocketry

Rocketry Organization of California

[4] The new RRS membership card design has been finished. Many thanks to Bill Janczewski for pulling this together. We have had a few requests for membership cards from members and the RRS has agreed to produce these only on demand.

Jim Gross will be the first recipient of this new style of RRS membership card. This year’s design has the 75th anniversary watermark on it.

The new 75th anniversary RRS membership card

There was some general discussion about the payment of dues. Even as we are growing in membership in our society, the RRS has not been collecting dues on a regular basis. We’re content to primarily use the honor system and gentle reminders to our membership to pay their annual dues of $40 per year or student memberships at $20 per year. It is this small revenue that helps the RRS stay on top of our bills. Student memberships are good as many university projects can require multiple tests at the RRS MTA which is covered with signing the RRS indemnification form and paying membership dues to the RRS.

All membership applications must be sent to the RRS president and approved by the RRS executive council.
president@rrs.org

Payment of RRS dues ($40) and the added cost of a membership card ($5) can be done by check and through the Paypal donation button we have on the RRS.ORG website. It’s important to make a note on Paypal that you’re paying your Membership Dues. The extra price of $5 for membership cards is pretty small and compensate for the cost of low-volume production as most members may not opt to get one. To those desiring a membership card, please contact the RRS secretary.

secretary@rrs.org

For all of our regular membership, I had proposed that the RRS return to using membership cards which were used in the past in the society. Membership cards were issued to all members upon payment and re-payment of their annual dues. This provides a physical mechanism to verify that each member is in good standing with dues paid. The membership cards would have their name and an expiration date that says when annual dues must be paid again.

Although some felt the idea had merit, others felt that we should continue to have the council take the initiative to track payments and remind members to pay their dues as we have been doing. Since members join at different times in the year, this can get complicated but we will rely on members to stay on top of this.

It was a good discussion that also raised issues about what constitutes “active status” in RRS membership and our broader membership policies including corresponding membership for those who live outside of the Los Angeles area but want to remain a part of the RRS in some capacity. It was agreed to revisit this broader topic in the July 2018 meeting as some of our newer members may not be familiar with the past and current membership policies at the RRS.

[5] Sam Austin gave his presentation the Hercules Rocket Engine project at MIT. His liquid rocket propellants are LOX and kerosene. Sam was kind enough to bring his liquid motor that he is finishing. It’s a 500 lbf, 600 psi LOX-kerosene engine with an unlike impinging injector. His stainless steel chamber with a graphite nozzle insert ought to hold up to short burn durations. Everyone was able to inspect the injector, chamber and nozzle parts that Sam made at the MIT machine shop. The delicate work to get a clean injector pattern was impressive. He’ll be water flow testing the injector soon to verify that everything looks right.

The RRS recommended Specialized Coatings, a ceramic coating vendor in Huntington Beach, that we have used with success in the past on alpha and beta nozzles.

Specialized Coatings – Huntington Beach, CA

Sam Austin’s liquid motor nozzle with graphite throat

Sam Austin’s injector assembly for his liquid rocket

Sam is still working on the propellant feed system. He already has a pair of liquid carbon dioxide vessels that are of the right size. After safely removing the original valves and getting the rest of his control plumbing, he will hopefully have what he needs to conduct testing at the RRS MTA or at FAR next month in July 2018.

There were a few questions about different features of Sam’s liquid motor, but overall it looks like it should work. Sam is getting prepared to finish the propellant supply system for a static fire of this rocket motor. With luck, he should be able to get into hot-fire at the RRS MTA or FAR site next month and hopefully before he returns to MIT in the fall. We are glad that Sam has decided to join the RRS as a student member.

The RRS membership had a few suggestions for improvement and a few recommendation for low cost regulators, ball valves and relief valves that have been used in other amateur and professional projects.

[+1] We managed to talk about one bonus topic by showing the video from the vertical static fire of the vehicle-sized solid motor by Jack Oswald and his team at the RRS on Thursday, June 7th. The video clearly shows a nozzle failure after two seconds from start, but it seemed that there may have been grain fracture leading to a partial blockage of the nozzle and then the resulting pressure surge shattered the nozzle. We may upload the video to our YouTube channel once we ask Jack and his team. Hopefully, Osvaldo can extract a few still photos from his footage. I think some of those stills will show an impressive start followed by a change in the flow pattern and abrupt failure with ejecting fireballs of propellant that followed. The RRS works safely and are glad to have our own remote testing site like the MTA to do these larger projects.

Sam’s presentation was very engaging, but we ran out of time before the Community Center closed at 9:00PM. We did not address all of our main agenda items or some of those added at the last minute. We will roll these topics to the July 2018 meeting.

* Osvaldo’s alpha parachute system and the video of its launch on 6/2/2018 at the MTA
* Getting a sign at our first metal gate as you reach the MTA
* Saturday morning seminars for members and how to get those started
+ Richard’s progress with the RRS standard liquid rocket
+ Discussion about the 2019 symposium

+ We did agree to discuss the topic of RRS membership policy and what constitutes being an active member.
+ Also, on the meeting agenda for July 2018 is the quarterly update on the SuperDosa project. I hope to have something ready to present by July 13th.

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

Again, we will have another launch event at the MTA on July 21th with the LAPD CSP program and member projects to be discussed later.

The next monthly meeting will be July 13th at the same place and time (7:30PM).

April 2018 meeting

The RRS held its monthly meeting on April 13, 2018 at the Ken Nakaoka Community Center in Gardena. We had a full agenda with the most important item being the 75th anniversary RRS symposium that is coming in only 8 days. We had a prompt start at 7:30pm with Osvaldo calling the meeting to order and giving the reading of the treasury report. We had a full attendance including our new RRS members, Jack, Dylan, Connor, Cooper and Byron from the former Chaminade High School rocketry club. They have been very busy with their solid rocket project. We didn’t have time to add their progress to our agenda, but we hope they’ll give an update at the May meeting.

Bill Janczewski and Chris Lujan just before the April 2018 meeting

The first agenda item discussed the work done by the Aerospace Corporation of El Segundo, California, on March 26th and 27th at the RRS MTA site. RRS member and Aerospace Corporation employee, Drew Cortopassi gave an excellent summary of the work. Aerospace Corporation’s experimental work was a success and we hope that Aerospace may return to use our site to advance their designs. Aerospace Corporation is one of our exhibitors and presenters at the meeting. A fuller discussion of their rocket testing at the RRS MTA will be given at the RRS’s 75th anniversary symposium, next Saturday, April 21st.

Aerospace Corporation tests an experimental solid motor design at the RRS MTA, 3/26/2018.

The next agenda topic was discussing the results from the launch event held last weekend with Florence Joyner Elementary School with the LAPD CSP program. Frank gave an excellent summary and Osvaldo discussed a theory explaining the odd bending of each alpha rocket found at the event. Most alpha rockets come down nearly vertically and burying themselves straight into the hard dry lake bed. At the launch event of April 7th, nearly all of the rocket propellant tubes were bent. Typically, this only happens if the rocket strikes a rock beneath the surface, but it is quite uncommon. Osvaldo’s invention of the Rockextractor proved to be a swift tool for reclaiming found alpha rockets.

Osvaldo’s newest invention, the Rockextractor

As a side note, Frank had mentioned that the USC short film “Rockets in the Projects” covering the November launch event with Grape Street Elementary class and the LAPD CSP program will be screened with other short films at Annenberg Hall on the campus of USC on Wednesday, April 18th. Seating is very limited so those interested in seeing the film should act quickly.

The third agenda topic was about the RRS expanding its roster of licensed pyrotechnic operators (pyro-op’s). We have great support from our current pyro-op’s but the society would benefit from having more. The RRS will be building a training manual that includes the materials mandated by the California Fire Marshal’s office to attain a license in rocketry. This tool will be an effective study tool for members looking to become licensed pyro-ops. At the very least, the training helps spread safe practices in the society. Given the limited time we had at this month’s meeting, we agreed to discuss this topic further at the next month’s meeting in May.

RRS pyro-op manual and training guide

The fourth agenda topic was something that Larry Hoffing discovered. The 2-bit Circus Foundation is a non-profit educational organization dedicated to the next generation of inventors to advance environmental stewardship and spur community engagement. The 2-bit circus has a futuristic arcade in downtown Los Angeles and has reached out to the RRS to be an exhibitor at their next event in Hawthorne, California. The RRS was supportive of this idea and once more details become available we will find a few members to attend the exhibition to help us reach more people at this event for STEAM (Science, Technology, Engineering, Art and Mathematics) education which our shared passion.

Two Bit Circus Foundation – STEAM education

The fifth agenda topic briefly discussed an idea that I have developed a second-stage design that fits with the RRS standard alpha payload tube. With a short segment of 1-1/4″ PVC tubing turned down to fit inside the 1.75″ OD payload tube and machined PVC end cap, a second stage motor with a graphite nozzle can be fired atop of the micrograin booster. A short length of Type-1 PVC round stock was donated to the RRS by Industrial Plastic Supply Inc. of Anaheim, California. There are many plastic suppliers, but not many that offer such a range of plastics in small quantities better suited for experimenters and hobbyists with modest personal budgets. I happily recommend them to all.

Industrial Plastic Supply Inc. – Anaheim, California

An interstage piece is necessary to trigger the second stage after a set time delay. I have designed an umbilical connector piece that uses a 3.5mm audio plug and panel-mount jack as a switch.

3.5 mm audio jack, panel mount

To internally mount the switch at a shallow angle for easy extraction of the plug as the alpha rocket lifts away from the launch rack required a unique plastic piece that Richard Garcia was able to 3D print for me in plastic. The fit check was a success so now I have to get the connector wired and mounted.

two of the umbilical jack mounts, plastic nozzle puck in the foreground

The solid motor grain itself was thought to be simple rocket candy, but other solid propellant types could be tried. Chris Lujan offered to pour a second stage grain for my design. Richard Garcia also offered to make his next motor grain to fit in this standard payload tube size. I have designed most pieces, but some aspects of this design need more work and testing. The RRS would like to encourage our members and our partner organizations to design and fly payloads with our standard alpha rockets which are easy to produce. Time was short so this topic was also tabled for the next month’s meeting as this work evolves.

RRS standard alpha, second stage assembly (work in progress)

The sixth agenda topic similarly had no real time to get into the details. The quarterly progress report of the SuperDosa project had only the RRS ballistic evaluation motor (BEM) to discuss. This workhorse tool will help the RRS accurately determine burn rate with variable nozzle puck sizes. Richard Garcia did turn out a basic set of graphite puck nozzles for the BEM.

RRS BEM graphite nozzle pucks, courtesy of Richard Garcia

The cylinder piece is with Osvaldo once he can find time to machine the bore and pressure ports. The top and bottom plates will be made soon by CNC Specialty Machining of Huntington Beach. This is the same machine shop that did a quality job with milling the S-type load cell adapter blocks for the RRS horizontal thrust stand. Thanks to Matt Moffitt of CNC Specialty Machining which is soon to relocate their business in Huntington Beach next month.

RRS ballistic evaluation motor design concept

The last agenda topic was the last preparations necessary for the RRS symposium coming next Saturday, April 21st. This event will easily be larger than last year’s event with over 400 Eventbrite reservations made just before the meeting. We have a longer list of speakers including new participants such as NASA Goddard Spaceflight Center’s (GSFC) Wallops Island Flight Facility (WFF) in Virginia. We will need all of our members to help us support this event. Please spread the word!

There will be a lot of work in setting up the night before. Members are encouraged to come help set things up at 7PM on the Friday night beforehand, April 20th. Contact Frank Miuccio who is our symposium coordinator if you would like to help.

vicepresident@rrs.org

The RRS meeting went out to the exhibition hall of the Ken Nakaoka Community Center in Gardena. The RRS will have the whole center for our public event and we hope everyone can come. Frank will send me the final agenda with the speaker list and the presentation times. This is an all-day event, but consult the RRS.ORG website for updated information. I plan to make a posting for the RRS symposium soon.

The meeting adjourned as the Ken Nakaoka Community Center closed. Osvaldo did some work for our new members with a clamping assembly to hold their rocket casing in their own horizontal thrust stand to test their full-sized boosted dart motor. Although independently conceived, this work nicely fits with the SuperDosa project and the RRS is glad to have another project to help advance the work of the society and our members.

RRS members stand outside of the Ken Nakaoka Community Center after the meeting with the horizontal thrust stand

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

Our next meeting will be Friday, May 11, 2018. Please come as we will have much to discuss after the symposium and plenty to do in this summer of our 75th anniversary as a society.

MTA launch event, 2018-04-07

The RRS held a launch event with the students of Florence Joyner Elementary School at the MTA on April 7th, 2018. This event was the final step in the five-week RRS program that started in February thanks to the support of the Los Angeles Police Department’s (LAPD) Community Safety Partnership (CSP). The students got a tour of the RRS Mojave Test Area where both amateurs and professionals can test rockets in the open space of the Mojave Desert.

Students from Flo Jo Elementary at the RRS MTA

As always, we gave a safety briefing to the students to the hazards of the desert and our testing site. Dave Crisalli was our pyro-op for the event and gave an excellent background of the exciting work we do at the RRS.

Dave Crisalli addresses the students and officers as Frank Miuccio looks on

Safety briefing inside of the George Dosa building at the RRS MTA

The tour also included a live demonstration of burning the micrograin zinc/sulfur powders in the open air. The bright yellowish flame is a vivid demonstration of the combustion process.

Live demonstration of micrograin propellant at the MTA

We also demonstrated the burning of a more common solid propellant, an ammonium perchlorate, HTPB and aluminum powder composite grain. The same constituents used in the Space Shuttle’s solid rocket boosters (SRB’s). Thanks to Larry Hoffing for making the sample grain for the test.

Sample of a composite solid propellant grain just before the demonstration.

The Flo Jo elementary class built 10 RRS standard alphas for the event. Each painted uniquely by each of the teams.

Standard alpha rockets from Flo Jo Elementary

Once everyone had the safety briefing and completed the tour, we proceed to send everyone to our safety bunker as Dave Crisalli and I loaded each rocket into our rail launcher.

Dave Crisalli and Dave Nordling load an alpha into the launching rack

Each of the rockets flew straight and fast from the rails and did not disappoint the class seeing their hard work fly off the rails in a huge yellow cloud.

wide-angle still shot from Osvaldo’s high-speed camera, 2018-04-07

An RRS alpha rocket takes off, view from the bunker

After the clean launch of all of the rockets, the kids and the LAPD ventured out to the desert to try to find each of their rockets. Flag poles were made for the occasion to mark the locations so that they could be extracted later by shovel. 7 out of 10 rockets were found and two older rockets from previous events were also found and marked. It is tough to find each rocket in the desert scrub, but with the hard work of the students it’s good to recover at least some of the parts as they can be reused with some work.

After launch, the students and their mentors march to the desert to search for their rockets

The kids were very organized and had a great time. After taking a group photo at the gate, they returned to the city. The RRS was glad to host them and hope they can come back soon. Also, thanks to the LAPD CSP program for being supporters of this project to give this experience to the hard-working students of Watts.

Flo Jo Elementary and LAPD CSP pose before the RRS MTA sign

The RRS membership stayed behind to try a few experiments. The first test was trying to finish the foot plate welds on the horizontal thrust stand I have made for static testing alpha rockets motors of similar size with S-type load cell donated to the RRS by Interface Force Inc.

Interface Inc. – Precision Load Cells

The construction of the horizontal thrust stand is nearly complete, but unfortunately the desert winds made welding of the plates impossible. This steel frame will firmly hold alpha-sized rockets for static fire testing when bolted down to concrete slab in front of the old blockhouse. As a historical note, it was a young Dave Crisalli that helped pour this slab in the late 1960’s.

Osvaldo prepares to weld the foot plates of the horizontal thrust frame at the MTA

Scribe marks were made on the plates and the assembly was taken back to the city to be completed later. Many thanks to Jim Shirley of Shirley Design and Custom Fabrication in Huntington Beach for finishing the structural welds. The integration of the load cell and final mounting to the concrete slab will take place at the next launch event where the RRS hopes to measure the thrust and impulse bit of our standard alpha rockets.

The RRS horizontal thrust stand frame is complete and ready for mounting at the MTA

Richard Garcia built his own vertical test frame to support a small steel engine case he made for a rocket-candy grain.

Richard mounts his frame to the MTA structure for his experiment.

Rocket-candy is a simple mixture of potassium nitrate and sugar. Under moderate heat, the sugar caramelizes to form a viscous but firm mixture that suspends the oxidizer and can be packed in to the paper tube cases.

Richard “cooks” the sugar and potassium nitrate under low heat of the electric hot plate.

Richard’s work was documented by RRS member, Alastair Martin, who is working on a larger documentary of the RRS classes and our members’ experimental work at the society.

Alastair Martin films the tools and process of Richard Garcia’s rocket candy production

Once the motor grains had set, they were test fired to verify the quality of the mixture. The second motor grain was loaded in the steel rocket tube mounted to the vertical stand. Results were not spectacular as the end-burner grain design didn’t create much pressure. More testing will be done to improve performance, but the steel case and nozzle were undamaged.

Richard Garcia’s steel motor case and nozzle, just before loading the motor grain

Richard’s sugar rocket motor fires securely from the vertical mounted stand

One of the newest tools invented by our president, Osvaldo Tarditti, is a new ratcheting tool that pulls the rocket straight from the ground by a simple portable frame that can be angled to get the rocket to come out straight. The tool must be operated by two people to pull the rocket body straight from the ground. The tool was successfully demonstrated and nine rockets were pulled from the ground without any of the back-breaking work of shoveling. This is an excellent advancement for the society and will be very handy in the future.

Osvaldo’s newest invention, the Rockextractor

As this is the first launch event of this 75th anniversary year of the society those of us that were at the MTA at the end of the day took a group photo by the old I-beam which has been a part of the RRS since our earliest days of rocket testing. You can see the I-beam by itself in many of the old society photos. At the new MTA site, it is an integral part of our larger test structure that has seen hundreds of uses and still going strong.

Frank Miuccio, Alastair Martin, Dave Nordling, Richard Garcia and Osvaldo Tarditti pose by the iconic RRS I-beam

The RRS will be having their next monthly meeting on Friday, April 13th. The RRS 75th anniversary symposium is also happening on Saturday, April 21st. Please come out as it will be a great occasion with speakers and exhibitors from industry, universities and other amateur rocketry groups.