Tag Archives: liquid rocket

December 2021 Virtual Meeting

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by Keith Yoerg (RRS Secretary)

The latest meeting of the Reaction Research Society took place by teleconference on Friday, December 10th and had twelve attendees.

Screenshot of discussion during the monthly meeting

RECAP OF KEITH YOERG’S NOVEMBER LAUNCH OF “THE HAWK”

Keith kicked off the meeting with a recap of the first launch of his rocket “The Hawk” an 8-inch diameter 14-foot tall rocket that was flown from the RRS Mojave Test Area on November 28th. The rocket utilized the 1515 rail launcher which was secured in place to one of the concrete pads using sandbags and tie-downs. The motor was a 98mm Cesaroni M1790 Skidmark which features sparks in the trail.

First launch of Keith Yoerg’s rocket “The Hawk”

Keith shared some slow-motion video of the flight captured with a GoPro camera and other data from the flight, including a 3D flight path. The rocket reached an altitude of 4,846 feet as measured by the barometer on the onboard AltusMetrum Telemega flight computer, and was successfully recovered with only minimal damage to the body tube. The rocket is in the process of being prepared for another launch on December 17th to coincide with the anniversary of the Wright Brothers first flight.

Map of the flight path with barometric altitudes in red and GPS in blue. The GPS appears less reliable on this flight.

RESULTS OF THE 2022 RRS EXECUTIVE COUNCIL ELECTIONS

Election chairman Drew Cortopassi presented the results of the 2022 executive council elections. The RRS Executive Council for 2022 is as follows:

President:    David Nordling
Vice President:    Frank Miuccio
Secretary:    Keith Yoerg
Treasurer:    Larry Hoffing

The society members in attendance congratulated the incoming new president and other incumbent officers and expressed their gratitude to outgoing president Osvaldo Tarditti for his stewardship of the organization. Osvaldo noted that the future of the group looks bright, and promised to send anyone who asks him a question a photo of him fishing.

USC SOLID ROCKET GRAINS STATIC FIRING

Osvaldo and Dimitri provided a recap of the lengthy solid rocket motor testing campaign that USC conducted at the MTA from December 4-5. On Saturday the 4th, the team worked through the night until around 2 am to be able to complete their goal of firing 20 separate grains of solid fuel by 2:45 pm on Sunday the 5th. The only reported mishap was that the U-Haul the USC team rented broke down just after leaving the dirt road to the MTA, which Dimitri suspected was because they had been using the battery from it to fire the rocket motors.

While the campaign was an ambitious one, the repetitious nature allowed them to get some of the younger students involved who wouldn’t normally be able to take part in on a day when only one motor is being fired. It was remarked that having more young members with hands-on experience is very good for the future of their program and the continuity of knowledge after the upperclassmen graduate. Dimitri mentioned that additional work will be needed to fill in the area of ground blasted away by all the recent USC solid rocket static firings – which has been affectionately named the “Trojan Trench.”

On the same weekend, a team at the FAR launch site launched their “Genesis” rocket – a hypergolic liquid propellant rocket that has been in development since the early 1980’s. Several RRS members had worked on the rocket at various times during its design and fabrication process. Unfortunately, the parachute system did not work and the tanks ruptured on the landing causing a small fire that self-extinguished but was visible from the MTA.

A THANK-YOU FOR DIMITRI’S RECENT WORK AT THE MTA

Our outgoing president, Osvaldo Tarditti, took a moment to extend a special thank you to RRS member Dimitri Timohovich for all of the recent work he has done in improving the facilities we have available at the MTA. Not only did he take the lead in the recent blockhouse roof repair which included several trips up to the site for the initial build, cutting the edges, and installing the tar paper, but he also donated four propane bottles for the society to use in the heaters and BBQ up at the Dosa Building.

The old blockhouse with a new roof.

In addition, Dimitri has agreed to take on the bulk of the work in building out the interior of the containerized bathroom. Three concrete pads have been poured at the MTA to accommodate this 20-foot high cube container as well as another one adjacent to it.

Future site of the RRS containerized restroom facility.

Osvaldo has procured most of the fixtures for the interior and plans to drop them off at Dimitri’s house – where the container will be delivered so that he can work on it more easily. Dimitri gave a tentative timeline of mid-January 2022 for when the container may be ready for transport out to the MTA.

PLANNING FOR MTA EVENT ON DECEMBER 17

Keith discussed his plans for a second launch of “The Hawk” on Friday, December 17th – this time on a Cesaroni N2600 motor. In addition, Dimitri has an RRS Standard Alpha rocket constructed and ready for launch and Osvaldo agreed to prepare one for Keith to get experience with the Zinc-Sulphur rockets. Dimitri volunteered to bring food for the group – award winning caribou chili made from meat they hunted, dressed, and prepped themselves in Alaska.

CALIFORNIA’S NEWEST ROCKETS CLASS 1 PYROTECHNICS OPERATOR

RRS member Dave Nordling informed the group that he recently learned that he passed his Class 1 Rockets Pyrotechnic Operator’s License exam. Congratulations Dave!

Office of the State Fire Marshall (OSFM) governs the licensing of pyrotechnic operators in California.

With additional members continuing to work towards earning their licenses, we can make sure that the RRS is able to accommodate a wide range of rocketry testing and schedule requests.

NEXT MONTHLY MEETING

As a reminder – yearly membership dues are due January 1st. Please click on the yellow “Donate” button on the right panel of this website to pay online via PayPal, or mail a check to the society post office box in Los Angeles.

Reaction Research Society; P. O. Box 90933; Los Angeles, California, 90009-0933

The next RRS monthly meeting will be held virtually on Friday, January 14th 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 are receiving the meeting invitation.

November 2021 Virtual Meeting

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by Keith Yoerg (RRS Secretary)

The latest meeting of the Reaction Research Society took place Friday, November 11th and had 14 attendees. After a brief discussion on updates to this website (which are currently underway), we got the meeting started.

Screenshot of discussion during the monthly meeting

NOMINATIONS FOR 2022 RRS EXECUTIVE COUNCIL ELECTIONS

Official proceedings began with the nomination of Drew Cortopassi as the election chairman for this year. The following candidates were nominated to the ballot for the listed offices (write-in candidates are allowed).

President:    David Nordling (new)
Vice President:    Frank Miuccio (incumbent)
Secretary:    Keith Yoerg (incumbent)
Treasurer:    Larry Hoffing (incumbent)

Administrative and lifetime members should have received a ballot via email. If you believe you should have received a ballot but did not, please contact the RRS treasurer (treasurer@rrs.org). Ballots must be submitted by Thursday, December 9, 2021. Election results will be announced at the December monthly meeting on Friday the 10th.

BLOCKHOUSE ROOF REPAIR RECAP

With the election business handled, Osvaldo proceeded to extend a hardy thank-you to the RRS members who assisted in replacing the aging blockhouse roof earlier in the month: Dimitri, Bill, Jon, and Keith. A few photos and a time-lapse video of the process were shown, and an extra thank-you was extended to Dimitri for his efforts over several weekends to both finish the roof and haul the materials to and from the MTA. A more detailed write-up of the process from Dimitri is available on this blog here.

DISCUSSION OF UPCOMING MTA EVENTS

Several groups appeared ready to take advantage of the cooler desert weather during the upcoming month. Most of these events have already taken place at the time of the writing of this report, but were still in the planning stages during the meeting. Reports will be available on this site for each event if they are not already.

The planned events included: on November 20th, UCLA conducting a static firing of an ethanol-LOX liquid rocket in support of attempting to earn the FAR-Mars prize for an altitude of 30,000 ft; on November 28th, Keith Yoerg launching his 8″ diameter, 13′ tall rocket “The Hawk” on a 98mm solid rocket motor; and on December 4th, USC conducting further tests on their 8″ solid rocket motor. Wolfram Blume also expressed interest in attending to continue work on his rocket the “Gas Guzzler.”

YOUTH ROCKETRY CLASSES

Frank updated the membership on the youth rocketry classes. The launch date for the class in Boyle Heights was rescheduled to January 22nd because of concern the students and group may not have had the logistics prepared for the field trip.

Classes with the “Strive” group (which had been discussed in more detail during previous meetings & their write-ups) have been scheduled to run from February 2nd – March 2nd at 4pm on Wednesdays. The launch for this class will take place on March 5th, with March 12th reserved as a contingency day. The plan is to use lessons learned from the Boyle Heights class to help inform how this class will be run, which will also use Baby Berth Estes model rocket kits so that each student will be able to take a rocket home after the launch. Frank is also working with the LAPD “Community Safety Program” (CSP) to schedule a class with that group for the summer of 2022.

Osvaldo showing off the e-match igniters sized for use in model rocket motors

Talking about the classes kicked off a discussion of the support the society has prepared for the launch day during these classes. Osvaldo showed an example of the igniters which we plan to use – something far more reliable than the nichrome wire igniters included with Estes rocket kits. Larry and Dimitri shared what they had learned about the Cobra Wireless Firing System which we intend to use to launch the rockets. Dave Nordling also updated the attendees on the status of the PVC launch pad systems he has been working on.

MISCELLANEOUS DISCUSSION

More RRS members keep catching the bug and deciding to build model rockets! Chris Lujan showed of a model rocket kit that he built with his son and they plan to launch during the next youth launch up at the MTA.

Chris showing off the rocket he built with his son

Keith Yoerg then did an impromptu presentation on the build process that he used for his rocket “The Hawk” by showing a series of photos that he took along the way. This project has been in process since early 2021, and it is very exciting to see it nearly complete!

Photo showing the epoxy injection process for the internal fin fillets on “The Hawk”

Fred Radford then shared about his 8″ rocket – one very similar to “The Hawk” – including some very clever tools for sanding and the build process. This rocket is expected to use s C02 cartridge system for the parachute deployment. Fred is building this and other rockets out of a Maker Nexus makerspace in the Bay Area of California, where he operates his nonprofit “Space Makerspace” to teach kids how to build rockets.

Photo of several of the rockets built in Fred’s classes

NEXT MONTHLY MEETING

The next RRS monthly meeting will be held virtually on Friday, December 10th 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, 2021-11-20

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by Dave Nordling, Reaction Research Society

The UCLA Project Prometheus held a static fire event at the RRS MTA for two of their latest designs of their liquid rocket engine. The pyrotechnic operator in charge was Osvaldo Tarditti with Dimitri Timohovich and myself as apprentices for these two static fire operations. This was a liquid ethanol and oxygen engine of the same 1500 lbf design used in prior years. There was a change in the injector pattern and a new ablative liner was used in the first of two engines.

UCLA positions their equipment and makes final checks before inspection from the pyrotechnic operator.

UCLA had come to the MTA on the prior afternoon to begin their setup with plans to be ready for the first of two hotfires when the pyrotechnic operator was to arrive that day. UCLA was in fact ready and after a short review of all plumbing and changes made since last year’s testing followed by the basic safety briefing to all attendees the tanking operations began.

During the pandemic, UCLA had a long pause without access to their laboratory. This time allowed the team to collaborate remotely and consider improving their testing rig which was deployed at the MTA for the first time.

The first engine hotfire had a few delays from the igniter failing to light in the last seconds of the count. The count was recycled with the same result. After the avionics team corrected the problem and the oxidizer supply was replenished, UCLA returned to their countdown and had a generally successful hotfire. The test ran the whole duration but the chamber internal wall ablative liner seemed to not be sufficient and a breach of the chamber jacket was seen.

Chamber ruptured on the first engine at the end of the burn after the ablative wall expired.

After purging the engine and safing the ground test system, UCLA waited for the engine to cool. Photos were taken of the post-test conditions and we all took a break for lunch before swapping engines for the second of two planned tests.

The second engine installed and ready.

The second engine had the old ablative liner material and went full duration without any obvious trouble. Also, the second engine used a small solid motor on a 3D-printed clamp-on mount which worked well. Similarly the engine was purged and allowed to cool before its removal for inspection back at the university. UCLA will likely examine the igniter firing circuit and system before their next engine firing or flight.

Second hotfire went full duration.
Group photo at the end of a successful day.

The team was very proud of the progress made and the data gathered will be very useful in anchoring their next flight vehicle’s performance. UCLA intends to surpass 30,000 feet with this next flight to claim the FAR-MARS prize. UCLA is still the current record holder at 22,000 feet from last year’s flight. Vehicle dry weight reductions in this year’s design and minor improvements to other vehicle systems could make the difference in claiming the prize.

The sun setting after a pleasant afternoon at the RRS MTA.

The old blockhouse had it’s roof replaced two weeks ago thanks to Dimitri Timohovich and other RRS members who lended a hand. Trimming of the roof beams was finished and the blockhouse was used for the first time with UCLA’s liquid rocket static fire.

As UCLA was packing up to depart the MTA, we used the time to build another wire launcher rail for model rockets in upcoming school events with LAPD CSP. Dimitri and his son, Max, launched a few volleys of some water rockets using a special system using an air compressor and solenoid firing box built for remote charging of nitrous oxide based hybrid motors. The system worked well and it was great fun.

Dimitri Timohovich reloads a water rocket based from Smartwater one-liter plastic bottles.
Under his father’s supervision, Max Timohovich prepares to launch the next volley of water rockets in the last hour of sunlight.