August 2021 Virtual Meeting

Posted on August 21, 2021 by kyoerg

by Keith Yoerg (RRS Secretary)

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.

Screenshot of discussion during the monthly 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 vicepresident@rrs.org for more details if interested.

Baby Bertha kit built by RRS Secretary Keith Yoerg

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.

Some info on the MASA liquid engine that is undergoing testing at the MTA

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.

Osvaldo showing his procedure for soldering a lead onto the nuts

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.

The switch & bulkhead installed in an Alpha rocket nosecone – note the leads attached to both nuts.

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 secretary@rrs.org.

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:

secretary@rrs.org

Please check your spam folders and add secretary@rrs.org to your email whitelist to make sure you receive the invitation.

MTA launch event, 2021-05-29

Posted on May 31, 2021 by Dave Nordling

by Dave Nordling, Reaction Research Society

The Reaction Research Society held a launch event at the Mojave Test Area mainly to support the UCLA Prometheus team for a static fire test of their high powered hybrid motor. UCLA chose one of the largest nitrous oxide hybrid motor designs, the M1575, made by Contrails Rocketry. Dave Crisalli was the pyrotechnic operator in charge for this event. I was his apprentice for the hybrid static fire.

There were three main activities at this event. The first was the UCLA Rocket Project making their preparations to launch their ethanol and LOX vehicle from the Friends of Amateur Rocketry (FAR) site from the 60-foot rail. FAR is just to the south of the RRS MTA where the UCLA Rocket Project had twice in one day static fired their 750 lbf liquid propellant rocket engine just four weeks earlier on 05-01-2021.

Weather conditions were ideal with winds being nearly still for most of the morning. This makes little difference for the hybrid motor static fire testing at the RRS MTA which was the second project by UCLA. Wind would factor heavily in the flight of the UCLA’s liquid rocket.

The third planned activity for UCLA was a series of model rocket flights from several high school teams mentored by UCLA graduate and undergraduate students. Still winds made for easier recovery of the first rockets launched that day.

UCLA Prometheus team prepares for static fire at the RRS MTA on 5-29-2021

Dave Crisalli gives the MTA safety briefing for the event in the loading area where the model rockets were assembled for flight.

UCLA graduate students conducted the model rocket launches from just west of the large test stand at the MTA

UCLA at the end of each Spring Quarter conducts a launch event where student groups build small rockets with egg payloads using single and dual-stage vehicles with model rocket class motors (G and under). UCLA graduate students and Professor Mitchell Spearrin were leading this event.

It is good experience for beginners and experts alike to build and fly model rockets., The RRS has it’s own such internal program called the Yoerg Challenge which is to motivate all members to build and fly a model rocket kit at least once from the RRS MTA. The RRS is known as an experimental society and not limited to the model rocket code, but we are also fully supportive of all forms of propulsion as long as it is safely conducted and compliant to the regulations set by the state of California.

As the UCLA hybrid rocket team was making their system checks, they discovered a problem in their nitrous filling system and valve commands. During this diagnostic period, some of the RRS members went to the nearby FAR site to see how the UCLA liquid rocket preparations were progressing.

UCLA’s liquid rocket set on the 60-foot rail launcher at FAR. The team preparing the vehicle for erecting, loading then flight.

RRS members from left to right, Bill Inman, Waldo Stakes, John Wells and Manuel Marquez, inspect the UCLA liquid rocket on the 60-foot launcher deployed at the FAR site.

A few last minute fixes and the rocket was made ready.

The liquid rocket sits on the rail before raising it for launch.

UCLA’s rocket is in position getting ready to clear the area for propellant loading and pressurization operations.

Some of the RRS members remained at the FAR site to witness the launch. After two years of design, planning, build and world pandemic, the UCLA team liquid rocket launch was an amazing success. Due to the relatively low winds that day under clear skies, recovery was made just under a mile away. Preliminary data from telemetry confirmed a new university team altitude record of 22,000 feet. It was an amazing sight to witness from the observation bunker at the RRS MTA.

UCLA’s liquid rocket had a perfect launch on 5-29-2021 setting a new altitude record of 22,000 feet by a university team. Photo by Xavier Marshall, RRS.

The UCLA Prometheus team had corrected their initial electrical problem and began the series of procedural checks to familiarize the new members of the hybrid rocket team. Some minor adjustments of the motor mount alignment was necessary before getting into test.

The UCLA Prometheus team makes some adjustments to better align the hybrid motor in the vertical skid mounted to classic I-beam at the RRS MTA.

The nitrous oxide K-bottle sits inverted in the sloped stand to allow the liquid to flow from the port. Some nitrous oxide bottles come with an internal siphon line to avoid having to invert the container. The bottle is also being chilled with ice to keep the oxidizer sufficiently dense and improve performance in hot-fire.

The top bulkhead of the hybrid motor is attached to the load cell for thrust measurement. A pressure transmitter is tapped into the nitrous oxide volume to further gauge performance.

The high-powered hybrid motor by Contrails uses four 1/4-inch fill lines and a single smaller vent line from the same floating injector at the mid-point inside

Dave Crisalli (right) inspects the hybrid motor on the test rails before the firing

UCLA Prometheus team tracks their written procedures as they progress to hot-fire in the old blockhouse.

The hybrid motor firing proceeded without further problems and resulted in a spectacular test meeting expected performance. Continuous thrust levels over 600 lbf were recorded but data analysis is still ongoing.

The UCLA hybrid motor at full thrust. Chamber pressure was over 1000 psia.

The team had a second hybrid motor grain ready for another firing so they proceeded with disassembly and inspection of the parts. The floating injector seals were still in good condition but the graphite nozzle having survived many prior hot fire tests did not survive that day’s test. Although the throat was in good condition, the inlet taper had cracked requiring a replacement the team did not have.

The top half of the floating injector with its internal siphon tube protruding up to near the top bulkhead.

The floating injector being removed from the lower half containing the spent fuel propellant grain.

The floating injector was removed after hot-fire and the dual O-ring seals were inspected. Seals were ok for re-use.

The nozzle assembly did not pass inspection after the first and only hot-fire on 05-29-2021.

The graphite nozzle fractured at the inlet taper from the first and only firing that day.

UCLA Prometheus was pleased with the results from the single firing and will proceed with integrating the motor into their flight vehicle for a launch from FAR on June 19, 2021. The RRS will hold an event at the Mojave Test Area on this same Saturday for member projects and will observe the flight from our northern vantage point.

UCLA avionics team conducted a few tests on the GPS tracking module that will fly on their vehicle in June 2021.

In the last hours of the day, after most of the UCLA liquid and hybrid teams had cleared the area, packaged and carried away their trash, packed their equipment and departed the RRS MTA and FAR sites. The UCLA avionics team remained at the MTA to conduct another series of tests on the GPS tracking system. The society was glad to support this diligence which will help assure success in one of the most important aspects of rocketry which is data acquisition from telemetry. If there is no data, it didn’t happen.

For any group interested in using the RRS MTA for their propulsion related projects, download one of our Standard Record Forms from our RRS.ORG website and submit this request to the RRS president. The society has had a long relationship with UCLA and USC, but we are also supportive to any amateur, professional or academic groups wanting to learn from test.

president@rrs.org

MTA launch event, 2021-05-01

Posted on May 2, 2021 by Dave Nordling

by Dave Nordling, Reaction Research Society

The Reaction Research Society held an event at the Mojave Test Area (MTA) on May 1, 2021. Dave Crisalli was the pyrotechnic operator in charge. RRS president, Osvaldo Tarditti, was also present along with myself, It was not to be a launch event as all planned tests were static firings by the UCLA liquid rocket team and the UCLA hybrid motor team. The winds were very high that day consistently above 20 MPH and gusts above 50 MPH at times. The weather otherwise was very cooperative with comfortable temperatures.

Other than gusting and persistently hugh winds, it was a great day at the MTA on 5/1/2021

Dave Crisalli gave a safety briefing in the George Dosa building to all attendees before the first static fire campaign would begin. The RRS pyrotechnic operator in charge is responsible for the safety of all during the event. Hazard identification (spiders, snakes, sharp objects) and good practices (hydration, sunscreen) are always part of the briefing, One of the most important things, Dave Crisalli mentioned was not to be in a hurry. It is very important to take the proper time to do things correctly and safely even if it means not proceeding with the intended test that day. Taking your time means avoiding mistakes and improving your chances for success.

Xavier Marshall observes the UCLA hybrid motor controls setup at the RRS MTA on 5/1/2021.

RRS members, Bill Inman and John Wells came to the MTA for the event, but only as spectators. The Solar Cat project is still active and undergoing improvements to its sun tracking method. Bill is also expanding the collector area and adjusting the necessary support structures. It is likely Bill and John will be back for the next RRS MTA event.

Dave Crisalli (left) and Bill Inman (right) at the RRS MTA vertical test stand on 5/1/2021

Also in attendance was the Compton Comet team who have all recently joined the society as members. It was their first time visiting the MTA and getting a chance to see another university team conduct liquid rocket test operations at our vertical test stand.

Members of the Compton Comet team, Manuel Marquez, Aarington Mitchell, Tre Willingham (from left to right) wait at the Observation Bunker at the MTA for the hybrid motor firing with Waldo Stakes (at right).

RRS member, Wolfram Blume came by the RRS MTA to take measurements of the vertical test stand for a future static fire test of his ramjet upper stage engine. He intends to use a leaf-blower compressor motor to simulate foward air flow, but a lot of calculations and planning is required before proceeding. The vertical test stand has a winch and pulley system still attached from Richard Garcia’s liquid motor test in 2017. It should be adequate for Wolfram’s lifting needs when mounting the test equipment to the stand.

The vertical test stand with the winch and pulley system still mounted.

The UCLA team spent the night before on our site setting up their equipment. This advanced planning paid off as they were ready for the first of two hot-fires of the liquid rocket just past noon.

Camera adjustments made before the first hot fire of the UCLA liquid rocket on 5/1/2021

Often, it can take several hours to verify all systems are in good working order before testing especially with a liquid rocket, The hybrid rocket was no exception that day.

The UCLA hybrid motor team installs the fuel grain and nozzle into the 98mm standard motor casing,

The UCLA hybrid motor mounted for static fire on the RRS MTA I-beam

One of the two load cells had failed so the two teams had to share the same load cell between the hybrid motor and liquid motor firings. UCLA chose to let the hybrid team go next after successful results were seen with the first firing, The UCLA hybrid motor team corrected a few issues and were able conduct a successful hot-fire by late afternoon.

The society members in attendance also had time to make some minor repairs to the new mobile trailer asset, A steel plate was added to keep intruders from entering. Thanks to Waldo Stakes for doing the welding for this temporary fix.

The mobile trailer at the RRS MTA needs a lot of repairs

There was sufficient daylight remaining for a second hot-fire of the UCLA liquid rocket, The team had another engine with the previous injector design from last built and ready with a fresh internal ablative liner. They had retanked another load of ethanol and the liquid oxygen cylinder had sufficient stores for another loading cycle.

Preparing for liquid oxygen transfer to the propellant tank

Thanks to the hard-won, acquired experience of the UCLA team and their commitment to training new members and holding to their proven procedures, they were able to conduct the second firing safely for an impressive finish that day.

The UCLA liquid rocket team poses before their liquid rocket after a second successful hot fire on the same day.

Initial data from both UCLA static firings of their liquid motor suggest that the 650 lbf nominal thrust motor outperformed expectations and will be ready for vehicle integration and flight by May 29, 2021. The UCLA team had reason to celebrate at the end of the day. The RRS was glad to be a part of UCLA’s continued campaign to fly liquid rockets that are competitive with any university team in the country.

For other universities interested in working with the RRS, please contact the society president submitting a Standard Record Form downloaded from our website,