MTA launch event, 2021-02-20

by Dave Nordling, Reaction Research Society


The Reaction Research Society held another launch event at the Mojave Test Area (MTA) on February 20, 2021. The weather was not cooperative for much of this day with wind gusts well beyond acceptable limits for launch (> 25 MPH). Our neighbor, Dave Crisalli and his Polaris Propulsion team, were using the Dosa Building as he had construction activities planned but were cancelled for that day. The RRS and Polaris Propulsion were glad to share the Dosa Building as we both made good use of the day.

The three planned objectives (weather permitting) for this MTA launch event were:

  • Build a new pit toilet restroom just north of the original site.
  • Conduct Solar Cat operations at the MTA
  • Conduct model rocket launches from Keith Yoerg’s new wire launcher array

THE ALL-SOLAR POWERED SOLAR CAT PROJECT

Bill Inman and his colleague, John Wells, made the long journey to the MTA from Nevada. Bill had made further improvements to the launching system and solar collector powering the Solar Cat steam rocket. He was able to and a remote tracking motor and drive system to further automate his solar concentrator, but several minor problems in setup prevented a launch that day.

Bill Inman and John Wells examine and prepare the solar collector system from the trailer at the east side of our MTA.
Photovoltaic panel mounted to the front of the collector to power the tracker.
Bill Inman and John Wells set up the latest iteration of the Solar Cat steam rocket from just west of the alpha and beta launch rails

Bill is striving to use an entirely solar powered system including a photovoltaic power system for his auxiliary functions. Because of the east to west passage of the sun through the sky, the steam rocket must be launched in a northerly direction. This is possible if done from the northern or western edges of our launch site.

Although the winds were excessive throughout most of the day, Bill could still conduct some assembly testing and even conduct steam rocket heating operations while keeping the rocket secure on the ground. Launch would only be attempted if the winds lowered in that time. Sadly, much of the day passed in correcting minor problems and system tests. The system proved ready but insufficient sunlight remained that day and launch would have to be conducted from the MTA at the next opportunity.

BUILDING A NEW PIT TOILET AT THE MTA

The society has been examining many improvements to our Mojave Test Area which has stood for over 65 years. The site has been improved over the many years but time has taken its toll and renovations are needed.

The top priority selected by our membership and visitors was the restroom facilities. Our short term plan was to build a second pit toilet while we work on plans for a more luxurious option in the longer term. This effort is viewed as a stopgap solution which will serve our society for at least a few years. Dmitri Timohovich and Wilbur Owens contributed greatly to this effort. With the many people we had at the site, we were able to start and complete the project with time to spare that day.

Our starting point for the project.
Wilbur operates the backhoe to get the trench dug for the sonotube. While Dmitri completes the wooden deck for the new pit toilet,
The precarious job of installing the sonotube once the pit is at the proper depth.
After getting sonotube vertical, the rest of the pit was filled with a few bucket loads of dirt and a few of us with shovels.
The new restroom deck gets placed and aligned with the new sonotube.
The toilet booth is removed from the original concrete platform. Our president, Osvaldo Tarditti, pauses a moment to consider how much crap our society has taken from our visitors and members alike,
The toilet booth is placed on the new platform, but first some further trimming of the sonotube must be done,
RRS secretary, Keith Yoerg, and RRS member, Dave Nordling, stand at the original concrete platform now filled flush to the surface with dirt. The task is nearly complete.
Once firmly affixed to the new platform, the toilet booth was fit checked by Dmitri Timohovich. He is signalling that our pit toilet is now ready for business.

The pit toilet project was a success thanks to both our members providing their physical and material labor and the careful planning and coordination that took place starting in this new year. This improvement project will be only one of several to come. We hope to make our remote testing site both more functional but also a bit more comfortable to all who visit us after many hours drive from the city.

LAUNCHING ROCKETS FROM A NEW MULTI-WIRE RAIL STRUCTURE

With the last hours of the day upon us, the winds had subsided to a more reasonable speed. Keith Yoerg had a few model rockets prepared for launch with commercial motors. He had also built a multi-wire launcher which is a convenient way to display and launch several small vehicles successively.

Max Timohovich (left) views the Baby Bertha and the Big Bertha rockets as they sit on the launch rail made from PVC pipe and fittings.

Second thing introduced at this MTA launch event was a four channel launch box built by Dmitri Timohovich. With a clean wood finish and a rugged latched case, this box proved its function well with the launch of three model rockets that day.

The new launch box was tested at the 2/20.2021 MTA launch event

After some glitches with the electric matches, Keith was able to launch and recover the Baby Bertha (A8-3) and the Big Bertha (A8-3) rockets. We got excellent footage of these classic model rocket types. The last of the three launches was the slightly larger Star Orbiter (E16-6) which left the rails cleanly and the recovery system deployed without issue. Although the winds had subsided sufficiently at ground level, the higher level winds carried the Star Orbiter for a long horizontal trek west well beyond the property line, After some searching, the Star Orbiter was lost to the desert hoping to be recovered

Baby Bertha leaps off the wire rail with its tiny A8-3 motor,
Big Bertha comes back under its parachute landing just to my left. This great video can be seen on the RRS Instagram account.
The last photo of the Star Orbiter as it sits on the pad before the wind carried it far to the west.

IN CLOSING

The team cleaned up the area and put away the gear at sunset. We talked about setting the next launch date in March 2021. We hope to have a new date set soon, likely after March 12th.


February 2021 Virtual Meeting

by Keith Yoerg (RRS Secretary)


The latest meeting of the Reaction Research Society took place this past Friday, February 12th and had 19 attendees – including several guest presenters. The meeting started with a discussion of the logistics surrounding the upcoming MTA launch & work event next Saturday, which overlaps with ongoing construction on Dave Crisalli’s adjacent land. The construction workers will be utilizing some of the MTA facilities, and following a discussion among RRS members it was agreed that the planned launch & work event could still be held without interfering with construction activities.

Screenshot of discussion during the monthly meeting

GUEST PRESENTATION – POLY RABBOTICS

Members from the Long Beach Polytechnic High School First Robotics Competition team made a presentation on their project and the adjustments they have had to make due to COVID-19 restrictions. Without being able to meet in person to fabricate and assemble parts on their robot, the student-run group has had to shift their work to virtual workshops and at-home competitions to keep their skills sharp. One such competition required teams of 3 to build a mini-robot able to climb a pole.

Title slide for the Poly Rabbotics presentation – checkout their cool logo!

Their team is currently meeting 3 times a week to prepare for competition later this year, which features an altered “at-home” layout. Despite the many challenges, it’s clear that this team is making the best of the situation and continuing to help their members gain knowledge and improve their skillsets.

GUEST PRESENTATION – CSULB ROCKETRY

A second guest presentation was provided by members of the Cal State Long Beach Rocketry team. They compete in the NASA Student Launch Competition which challenges teams to design, build, and fly a rocket to between 3,500 ft and 5,500 ft while carrying a drone payload. The drone must deploy away from the rocket and fly to a specific position.

Presenter Dan Dao in the CSULB campus lab in Feb. 2020.

Fortunately, this team has been able to continue fabrication work on their rocket by following strict precautions to avoid the spread of COVID-19. Their shop site is on the Starbase campus at the Los Alamitos Joint Forces Training Base, and only a small number of specific team members are allowed on site. During competition last year the team placed 12th out of 46 total entrants, and they hope to finish in the top-10 this year.

PLANS FOR THE UPCOMING MTA EVENT

The primary focus for the upcoming MTA event is construction of a new pit toilet on the property. Dimitri plans to build a wooden platform this week and transport it out to the MTA site on Saturday, along with a sonotube liner for the pit. The wooden platform will rest on posts dug into the ground, and once in place we will remove the port-a-john from its current concrete plinth and secure it to this new platform. Work on welding the new plate on the vertical test stand, clearing nearby brush, and other site maintenance could take place if time allows.

Bill Inman plans to continue work on his solar-powered steam rocket, which uses mirrors to heat water with sunlight. Seemingly unsatisfied with any energy source other than the flaming ball in the sky, Bill has decided to modify his setup so that the tracking mechanism (which automatically tilts the solar collector to track the sun) is powered by a solar panel. Bill will be testing this new setup at the next event and may attempt a launch of the steam rocket.

Mockup of the internals for Dimitri’s hybrid rocket module

Keith will bring his high power solid rockets “Charlie Horse” and “X2”, and intends to launch at least one of them. The goal of the launch will be to test whether the LoRa GPS trackers, which have been discussed at previous RRS meetings, can be used as a cheap way to track rockets. Dimitri is finishing work on a 4-pad solid rocket launch controller (a layout is shown above) as well as a water rocket launch controller, both of which should be ready for testing on Saturday. A discussion on what food should be grilled at the event was concluded immediately after Dave Nordling’s suggestion – brats.

RRS HISTORY

An additional guest with a connection to the society joined us for this meeting – Tom Hendricks. He was a member of the RRS from 1959 – 1960 while he was a student at Glendale High School. He recounted launching micrograin rockets fueled by zinc dust and sulphur, displayed a rocket nozzle he had once launched, and recalled that the only test stand at the MTA site at that time was a lone I-beam (there’s a lot more on-site now!).

Tom also mentioned that back when he was an active member, the majority of the fabrication for the RRS was provided by 1 society member who had a lathe in their home. Many current members were excited to have Tom back in the fold, and he expressed a desire to join us for an event at the MTA soon. We’re looking forward to having him!

EXECUTIVE COUNCIL MEETING RECAP

The final item of business was a recap of topics covered during the January 2021 meeting of the RRS executive council. Council members have received the recommended edits to the constitution from the 2020 Constitutional Committee, and expect to have a version ready for the voting membership to review during the March meeting.

Image of Chris Lujan explaining different setups for security cameras

Council members Keith and Larry have been working on plans to install a security camera at the MTA, and presented the current status of the project. The goal is to have a network hotspot run WiFi security cameras. The project will start with the installation of a hotpot in the Dosa building (once shipped from backorder). The plan is to power the hotspot with a solar panel and determine the installation location that provides the maximum WiFi signal range. This will allow for optimum placement of WIFi security cameras. Chris Lujan has a lot of experience with home security cameras as a result of personal research, and shared that knowledge to help with the project.

NEXT MONTHLY MEETING

The next RRS monthly meeting will be held virtually on Friday, March 12th at 7:30 pm pacific time. Current members will receive an invite via e-mail the week of the meeting. Non-members can request an invitation by sending an email to:

secretary@rrs.org

MTA launch event, 2020-11-07

By Dave Nordling, Reaction Research Society


The RRS held a launch event at the Mojave Test Area on November 7, 2020. It was a largely overcast day with brief periods of sun. The daytime temperatures reached only 50 Fahrenheit but the winds were no more than 20 miles per hour which meets the criteria for safe launch. Osvaldo Tarditti, our society president, was the pyrotechnic operator in charge for this event.

RECOVERY OF ANOTHER ALPHA FROM JULY

John Krell was able to find the standard length micrograin alpha rocket laumched at the July 2020 event. The rocket was found further north than expected but the downrange distance was about right. This was the rocket with the ceramic coated nozzle which was to have its performance compared to the standard alpha with a plain steel nozzle which is known to erode from the high temperature exhaust.

Recovered standard alpha from the July 2020 launch
The standard length alpha was recovered with its nozzle and the ceramic lined throat. No erosion seems to be present.

Unfortunately, the data was absent on the memory chip. It appears there was a malfunction and flight data wasn’t recorded. John is looking into the problem.

The nozzle was removed and inspected from the recovered alpha. Preliminary results show that the nozzle stayed intact. Careful removal of the largely zinc metallic residue firmly adhered to the entrance and nozzle throat must be done to determine how well the ceramic coating survived the 2300 Fahrenheit flame temperature for the quick four-tenths of a second burn time, John Krell is trying a traditional remedy of heated white vinegar (acetic acid) which has been modestly successful in this application.

The golden color of the coating can be seen at the inlet. The condition of the coating around the throat is what must be determined.

A FEW ROCKETS IN NOVEMBER

Keith Yoerg and a few others launched five model rockets from the MTA event that day. We’re getting a lot more participants at our launch events which is a trend the society will encourage as we are expanding our organization by supporting a range of projects.

  1. The first was “Star Orbiter” which was prepared and launched by Wilbur Owens, and successfully recovered about 3/4 of a mile from the launch site. 
  2. The second launch of the “29mm Rocket” was prepared and launched by Ivan DeDios, and unfortunately was not found after a lengthy search. 
  3. The third launch of the day was “Charlie Horse” and featured the largest motor flown that day. The rocket was prepared and launched by Keith Yoerg and resulted in his first flight above Mach 1.0. In addition, it was the first flight of a GPS carabiner used to track the rocket which performed extremely well & was easy to use. Cheaper options of similar technology are being researched for future flights.
  4. The fourth launch was the “Bell X-2” which was prepared and launched by Keith Yoerg, and was a textbook flight with a simple recovery.
  5. The fifth and final launch of the day was “Low and Slow” which was prepared and launched by Alexander Jones. Unfortunately, the parachute failed to deploy at apogee and the rocket came back ballistically & was destroyed along with one of the carabiner GPS units.
The aptly named “29mm rocket” by Keith Yoerg, powered by a 29mm H115 Darkmatter motor, seen at take-off from the RRS MTA on 11-07-2020
The 29mm Rocket taking off.
Keith Yoerg’s “Charlie Horse” takes flight again frim the RRS MTA on 11-07-2020 powered by a 38mm J520 Skidmark motor.
A great still capture on the Bell X-2 at launch.
Camera view of the Low and Slow rocket at take-off
The recovered remains of the “Low and Slow” rocket by Alexander Jones.

The RRS encourages all forms of reaction-based propulsion including commercial solid motor rocket flights. We have our traditional love for the micrograin rockets, but our society is open to all ideas as long as they contact the society and our pyro-op in charge well in advance of our launch events.

The five commercial solid motors laid out on display.

BILL INMAN’S SOLAR COLLECTOR

Bill Inman came out to the MTA to test his next prototype of a solar collector. Bill’s latest project is exploring the idea of a solar-based heating system for a steam rocket. This second device had a wider collection area and a longer pipe length. He didn’t have good sun conditions that day and his larger collector structure was a little unstable in the wind, but he was able to get ideas for improvement.

Dimitri Timohovich aids Bill Inman in deploying his second generation prototype solar heater. It was a less than ideal day for solar insolation at the RRS MTA. Even the Mojave Desert can be cold on winter days.
A wider collector area in the new design. It was a less than sunny day.

There was a very short period of sun that day and in that time a measurable temperature gain was seen with the new collector.

A wider view of Bill’s solar collector

Testing the same device in the days following the MTA event at another location showed this second design to be a substantial improvement with the larger parabolic mirror area which allowed the water pipe to reach fluid temperatures exceeding 300 Fahrenheit and internal pressures of 90 psig. This is closer to Bill’s goal of reaching above 400 Fahrenheit for his next generation steam rocket from his successful Scalded Cat design almost 20 years ago.

Vapor curve data for water, psia in the left column, degrees Fahrenheit on the right.
The vspor curve of water showing the whole range from triple-point to critical point.

STATIC FIRE OF THE USC RPL ALUMNI SOLID MOTOR

A group of USC RPL alumni static fired an 8-inch solid motor at the MTA. The team worked very hard from the night before and all through the day in getting the motor ready for static fire. The RRS MTA is an excellent location for these operations and conducting safe motor testing.

Unfortunately with some experiments, the results can be disappointing. The hot-fire in the very last hours of daylight ended with a rupture near the bulkhead after roughly one second of the burn.

The 8-inch motor in preparation for testing.
Preparation at the pad as the afternoon is fading at the MTA
Photo of the static firing, less than ideal performance

IN CLOSING

The details of the event will likely be discussed at the monthly meeting teleconference on November 13th. We’ll be also discussing our next launch event to be held next month in December.

We will likely attempt the nitrous oxide hybrid motor with the modified igniter. The colder temperatures should allow the propellant manifold to operate properly without any modifications.

The removal and replacement of the bent panel on the vertical thrust stand was deferred because of USC’s static firing of their solid motor. This maintenance activity will remain a high priority since the replacement plates are ready and at the MTA already.

Thanks to the many members that contributed to this report. We will be planning our next launch event for the month of December at the monthly meeting scheduled for Friday, November 13th.