by Keith Yoerg, Reaction Research Society Secretary
The RRS Mojave Test Area (MTA) hosted a launch event and work party on Sunday, September 26th. The USC Rocket Propulsion Lab (USCRPL) had arrived a few days earlier to prepare for a static firing of their 8″ diameter solid rocket motor named “Earthshaker II” which took place on the 26th. Several RRS members also answered the “Yoerg Challenge” to launch model rockets, and Dimitri was out with his water rockets. On the work side of things the Dosa building was re-organized, a security camera was installed, and a discussion began on how best to replace the aging roof on the blockhouse.
USCRPL 8″ SOLID ROCKET STATIC TEST
USCRPL had their setup ready for a static test of their 8″ solid rocket motor in the late afternoon, which was secured below the vertical test stand. Unfortunately, shortly after coming up to full power the motor exploded. All personnel were at a safe distance in the bunker and no one was injured. RRS President and Pyrotechnic Operator in charge Osvaldo approached the site once it was safe and extinguished the resulting flames.
All requests to use the RRS MTA must be made to the RRS president and reviewed by the executive council. For any questions about this test series or any future test series, please contact the RRS president.
YOERG CHALLENGE MODEL ROCKET LAUNCHES
Many RRS members had model rockets on hand to answer the “Yoerg Challenge” and launch at the MTA site. Dimitri and his son Max launched a “Helios” and “Dazzler” on C6-3 motors. Keith launched a “Baby Bertha” on a B6-4 and a “Big Bertha” on a B6-2. Dave Nordling launched a “Baby Bertha” on an A motor. Bill Inman & Jon Wells also launched model rocket kits, and John Krell launched a model kit on a G motor. (I will endeavor to do a better job of recording the rockets & motors that everyone uses at these launches for more specific reports in the future).
We did not have the new wireless Cobra firing system at the MTA site during this event, so we used the 4-pad controller that Dimitri built earlier this year. The controller split its time between this low-power launch pad and the water rockets which Dimitri had set up on the underground blockhouse.
I will also mention that prior to these launches, we enjoyed a nice potluck BBQ of brats, (homegrown) potato salad, chips, beans, and corn. Several members contributed food which was expertly prepared by Becky. We’ve been doing this more often and seem to keep getting better at it every time!
WORK PARTY TASKS
In addition to the more exciting “fiery” aspects of the day, RRS members also completed a lot of routine maintenance at the MTA site. We completed several general organization tasks in the Dosa Building and the storage containers, and a security camera was installed on the Dosa Building. There was also a lengthy and robust conversation about methods to replace the aging blockhouse roof, which has been high on the the society’s list of desired site improvements for several years.
The latest meeting of the Reaction Research Society took place Friday, September 10th and had 16 attendees, including several members of the University of Michigan Aeronautical Science Association (MASA) team which conducted a long campaign of testing at our MTA site last month. After brief hellos & a short discussion on updates to this website, we got the meeting rolling with a presentation from the MASA team debriefing us on their August tests.
PRESENTATION ON MASA CAMPAIGN AT THE MTA
4 members of the MASA team who were present for the long campaign of testing at the MTA site were at the meeting and provided a presentation detailing how the nearly 2 weeks of work went for the team. A detailed write-up from RRS member Dave Nordling who was on site assisting for some of that time is available here.
While the end goal of conducting a hot fire test was not accomplished, there was a ton of great work and learning opportunities for both the MASA team and the RRS. The first challenge for the MASA team was in driving their equipment all the way from Michigan to Southern California. Unfortunately, they had some equipment suffer damage during the trip when their smaller “Ground Support Equipment” (GSE) trailer broke through the plywood floor of their larger travel trailer. This required them to stop in Texas and complete repairs to the travel trailer before continuing on to the MTA site.
Once at the site, the MASA team set up a 2-shift schedule (9am – 6pm and 5pm – 12am) effectively working 18-hour days to conduct the activities required for their tests. Many of these tasks took a lot longer than the team had anticipated, in particular with the supply and delivery of the gas & cryogenics needed. The MASA team was originally in contact with Airgas, but their communication was with the office closer to their home in the Midwest and not the Southern California branch. Ultimately sorting through those issues proved to be too difficult to secure a delivery while the team was at the MTA, but fortunately they were able to work with Praxair to secure a supply of the gas and cryo.
Once the gas and cryogenics were at the site, the team was able to complete pressure tests of the fuel side of the system, and were ultimately able to perform 2 coldflow tests through the entire system near their target pressures. These tests revealed many more areas for design improvements that the team hopes to implement, including reducing fittings, changing the location of vents and drains, and possibly even replacing the LOx and fuel tanks.
This campaign goes down in the books as the longest to ever take place in RRS history, and proved to be challenging for both the MASA team and the RRS. Several society members graciously volunteered their time to help make this testing effort possible, and the experience revealed many ways that the society could improve our procedures to better support extensive tests like this. Namely: limiting the duration of a test period to no longer than 1 consecutive week, requesting that some members of University staff be on-site when these long campaigns take place, and requiring a longer notice time before approving this sort of test were all brought up by RRS president Osvaldo.
Progress is continuing on the permanent RRS Bathroom structure. Work on cutting holes for doors and windows has been completed on the 20-foot shipping container and delivery is expected imminently to the new work site at Wilbur’s hangar. The next stages of construction including adding plumbing, fixtures, and the doors and windows, and Osvaldo has already acquired some of these items to install
SEPTEMBER MTA EVENT & WORK PARTY
The USC Rocket Propulsion Lab (USCRPL) plan to be out at the MTA site from Friday, September 24th – Sunday, September 26th to conduct a static fire of an 8″ diameter solid rocket motor. The first few days will consist of prep work and the firing is planned on that Sunday. Several members including Bill Inman and John Krell indicated in the meeting that they have stepped up to the Yoerg Challenge and built model rocket kits to fly at the MTA. This will give us a great excuse to test out the new PVC wire rail launchers as well as the newly purchased Cobra wireless firing system.
In addition, the society has decided to use Sunday, September 26th as the date for our annual “Work Party” to perform maintenance and cleaning tasks at the MTA site. The expected tasks we would like to complete are:
Weld the plate on the vertical test stand
Removal of dry vegetation
Move drum of RP1 (from MASA testing) into one of the lockable containers
Fix the 2 broken latches on the Dosa Building roll door
Prep/measurements in area for new container bathroom
YOUTH ROCKETRY CLASS
RRS Vice President Frank updated the membership on the upcoming youth rocketry class in Boyle Heights with details on the schedule and overall plan. As opposed to 2 alternating classes, we will now be working with a single class of up to 30 students. The classes will run every Friday starting on September 24th, with a launch planned at the MTA site on November 13th. The plan is for each student to build their own Estes Baby Bertha kit and fly it twice on launch day. RRS Secretary Keith is currently working on 3D printing fin alignment jigs for the students, which will help in both teaching the students about that technology as well as properly installing straight & aligned fins on their rocket kits.
The end of the meeting consisted mostly of miscellaneous discussions around the various projects that RRS members are currently working on. Some of the highlights included John Krell’s new, very small (20x80mm) electronics board capable of collecting 7 channels of data onboard a flight, with over half of those channels at 500 Hz! Bill Inman updated members on the progress with his Solar Cat steam rocket, and there was a brief discussion of ham radio operations with Tom Hendricks sharing some of his wealth of knowledge in that subject. Overall it was a fun meeting with a lot of good discussion & participation from the membership.
NEXT MONTHLY MEETING
The next RRS monthly meeting will be held virtually on Friday, October 8th at 7:30 pm pacific time. Current members will receive an invite via e-mail the week of the meeting. Non-members (or members who have not received recent invites) can request an invitation by sending an email to:
Please check your spam folders and add email@example.com to your email whitelist to make sure you receive the invitation.
The latest meeting of the Reaction Research Society took place Friday, August 13th and had 12 attendees who came and went, including a prospective student member. We had a lot of topics to discuss and some members had to leave early so we got right down to society business from the start of the meeting.
YOUTH ROCKETRY CLASS PLANNING & UPDATES
The RRS starting to plan for youth outreach classes – which have been on hold during the COVID-19 pandemic. Unfortunately, due to the delta variant the LAPD classes that were being planned for September at the Strive learning center have been postponed. However, it looks like we are on track to begin classes with the Boyle Heights YMCA after labor day.
This class is expected to have up to 60 students – which will be split into 2 groups that will attend every other Friday at 4pm on a rotating schedule. The current plan is to hold 5 classes per group, which means the program will run for 10 straight weeks. Any RRS member interested in helping during these classes will be required to complete a LiveScan background check. Please contact Frank at firstname.lastname@example.org for more details if interested.
The current plan is for each student to build their own “Baby Bertha” model rocket manufactured by Estes. The EC is currently organizing logistics to allow each student an opportunity to fly their rocket twice (assuming the first launch is successful, of course!) at our MTA site in late October or early November. In addition, we are looking at the instructors building a high power rocket in tandem to show the similarities and differences between the construction methods. A demonstration flight of the high power rocket would be held on the same day as the model rocket flights, to give the kids a sense of what a more powerful flight would look like.
Discussion at the meeting included ideas around fast-drying non-toxic glue options for the model rockets, 3D printed fin alignment jigs to ensure arrow-straight flights of the kits, and logistics around the launch day like adding more low-power launch pad capabilities to the MTA site. We may also try to add an onboard camera to the high power kit to show the students a view of the ground falling away from onboard the rocket!
PERMANENT BATHROOM & OTHER MTA UPGRADES
Progress is continuing on the permanent RRS Bathroom structure. Work on cutting holes for doors and windows has been completed on the 20-foot shipping container and delivery is expected imminently to the new work site at Wilbur’s hangar. The next stages of construction including adding plumbing, fixtures, and the doors and windows.
RRS president Osvaldo informed the membership that he purchased a forklift attachment for the backhoe that is stationed in the Mojave desert – which will be a great help with moving tanks and other heavy items that are often required for liquid rocket tests at the MTA. Members also discussed upgrading the launch structures at the site, including an idea for an adapter to allow Alpha and Beta micrograin rockets to use the same rail system and moving over the large launch tower from the “graveyard” on the northern end of the MTA to a more permanent & upright location.
AUGUST MTA LAUNCH EVENTS
After a short review of the July MTA events (writeups by Dave Nordling can be found here and here), members were briefed on the “long campaign” work that is underway by the University of Michigan rocket club “MASA” this month. While typical events at our desert site last only 1-2 days, this campaign is expected to run for 10 or even 14 days total. The exact length of time that they will be at the site depends on how quickly they are able to meet their objectives.
The ultimate goal of the campaign is to conduct a static, hot fire of their 2,500 lbf (10s total impulse) liquid rocket engine. The engine runs on RP-1 and LOX, and utilizes liquid nitrogen and helium as pressurants. Several RRS members and Pryotechnic Operators have generously volunteered their time on both weekdays and weekends to assist the student team in meeting their goals. A writeup of the events will be posted to this site after the testing.
OSVALDO’S MICROGRAIN ROCKET AVIONICS
RRS president Osvaldo Tarditti provided a show-and-tell of his screw type avionics switch, a very clever way to activate onboard rocket electronics when space is at a premium. This is certainly the case in the RRS Alpha and Beta micrograin rockets – which this switch was designed for. The basic mechanism uses 2 sets of electrically separated nuts with wire leads soldered on, which are epoxied to a bulkhead and affixed to the inside of the rocket’s nosecone.
When a screw is inserted – the circuit is completed between the nuts and the attached electronics turn on. With proper placement of the bulkhead and a hole drilled in the nosecone, this screw can be installed from the outside of the rocket just prior to launch.
Osvaldo completed the avionics package with a mercury switch and a cheap timing circuit board with multiple programming options. When placed together and activated on the launch pad, the mercury switch is jostled during launch which starts the countdown on the timing circuit board. When pre-programmed with the proper timing delay, the timing board countdown will coincide with the apogee of the rocket’s flight path and deploy a parachute. The hope is that this will allow for a more consistent recovery of Alpha & Beta rockets after launches.
CESARONI TECHNOLOGY / CESARONI AEROSPACE
Late in the meeting we were joined by RRS member and rocketry entrepreneur Anthony Cesaroni, who told members more about his companies and the time he spent at the MTA back in the 90s. With locations in Toronto, Florida, and Spaceport America (New Mexico) Anthony’s companies are major players in munitions, solid rocket motors, and even liquid engine components for Virgin Galactic. Among the major projects underway currently is a full 4-stage orbital vehicle, with hopes of full launches from Wallops and Kennedy Space Center in the 2023/2024 timeframe. Members were very excited welcome Anthony back into the fold and hear about the great work his companies are doing.
RRS WEBSITE UPDATES
The final topic of the evening was regarding updates to this website. The general consensus among members was that it is time for a fresh look and modernization to the website, and there was a robust discussion of the different avenues (and associated prices) that could be pursued. Anyone interested in helping to make this a reality can contact RRS secretary Keith at email@example.com.
NEXT MONTHLY MEETING
The next RRS monthly meeting will be held virtually on Friday, August 11th at 7:30 pm pacific time. Current members will receive an invite via e-mail the week of the meeting. Non-members (or members who have not received recent invites) can request an invitation by sending an email to:
Please check your spam folders and add firstname.lastname@example.org to your email whitelist to make sure you receive the invitation.