December 2021 Virtual Meeting

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


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.


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.


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.


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.


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.


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.


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:

Please check your spam folders and add to your email whitelist to make sure you are receiving the meeting invitation.

November 2021 Virtual Meeting

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


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 ( Ballots must be submitted by Thursday, December 9, 2021. Election results will be announced at the December monthly meeting on Friday the 10th.


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.


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.”


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.


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


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:

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

MTA Blockhouse Repair Nov 6-7, 2021

by Dimitri Timohovich, RRS.ORG

Saturday started with bringing the loader over from FAR.

Loader and blockhouse with the old roof
Blockhouse with old roof timbers removed

Bill and Jon arrived as the demo was finishing up and we quickly jumped into removing the nuts that held the old 2x6s on top of the cinder block walls. 

It was a pleasant surprise to see that all the cells were filled with concrete.  Bill and Jon cleaned the bolts while I cut the new 2x6s and drilled new holes for the bolts to go through.

Bolts in the blockhouse walls

We attached the new 2x6s and added an additional one to the front of the blockhouse to give the roof a slope to shed rain water.  By the time this was done, it was lunch time.

Bill Inman looking at his favorite rocket power source
Another shot of the 2×6 beams installed on the blockhouse

After lunch the 1 1/8” Tongue and Groove plywood was installed.  I brought the loader over from FAR and Jon was able to send up pieces in the bucket.  The wind started to pick up and we had to fight a little to get the plywood in.  After lining it up and tapping the sheets together I screwed them down to the 2x6s.

Plywood installed on the blockhouse roof

We then used the loader to lift up a couple of the timbers into place and were able to do a test fit.  By now it was getting late and we decided to call it a day.

The first railroad timbers in place for a test fit
Discussions with our neighbors near the end of daylight
Getting the alignment right for the timbers & adding screws
Blockhouse state at the end of the first day of work

Sunday morning was dedicated to getting all the timbers up onto the roof and screwing them to the plywood and also to each other.

Working on installing the rest of the timbers
Jon Wells using the loader to lift timbers on top of the blockhouse as Dimitri moves them into place
View of the blockhouse from the vertical test stand with all the timbers installed

Keith Yoerg was able to come out for the day.  He wanted to do a couple of tests on the parachute deployment charges for his upcoming launch.

Still shot from a video of Keith’s drogue parachute test

After two successful tests (drogue and main parachutes), he jumped in and helped get lumber up to the roof, cleaning the site, and helping install the trim work.  He also received a crash course in how to drive a piece of heavy machinery and drove the loader for the first time.

Keith in the loader after learning how to operate it

After the timbers were all placed and secured, the top sheeting of 11/32” plywood was screwed down to them.  Some trim work was applied to cover up the gap created by having a sloped roof.

Picture from Saturday before timbers were installed showing the roof slope
Trim installed under the sloped roof

We tried to lay down the roofing paper, but the winds picked up and we had one of the cut sheets fly off the roof twice so we decided to leave that for next time

With a little sunlight left in the day, the USC trench was filled in before the loader was taken back to the FAR site.

Dimitri filling in the “USC Trench”
Dramatic lighting as Dimitri continues to fill in the USC Trench