April 2022 virtual meeting

by Keith Yoerg (RRS Secretary)


The latest meeting of the Reaction Research Society was held Friday, April 8th 2022 and had twenty-two attendees, including several student presenters from the UCSD Colossus project.

Screenshot of discussion during the monthly meeting

PRESENTATION FROM UCSD COLOSSUS TEAM

The meeting began with a presentation from the University of California San Diego (UCSD) Students for the Exploration & Development of Space (SEDS) team, led by the Colossus Project Manager Shannon Lin. Colossus is a trailer-mounted thrust stand developed by UCSD students with funding from a NASA grant, intended to accommodate a wide range of liquid bi-propellant rocket engines (up to 3,000 lbf).

Title slide from the UCSD presentation

The UCSD team hopes to market use time on Colossus to student, amateur, and professional groups that are building liquid rockets and would like to collect data without designing and building their own thrust stand. Colossus can collect concurrent data from 13 pressure transducers, 8 thermocouples, and 5 load cells at 1,000 Hz sample rate. They also expect to add a 20,000 fps high-speed camera as well as a mass-spectrometry camera to their data collection options.

The presentation prompted many questions from RRS members, and there was a lengthy description of the prior failure, refurbishment, and upgrades made to their mobile and modular test stand. The team expects to conduct coldflow testing in the coming months, and hope to use the MTA to test fire a CalTech rocket and a UCSD project sometime in the coming summer.

REVIEW OF RECENT MTA EVENTS

Following the UCSD presentation, membership discussed the recent events at the MTA since the March meeting. On March 12, Dimitri delivered and placed the new 40-foot storage container, Bill Inman performed his second and final burst test of a fired vessel for steam rocketry, and members conducted low and high-power launches. A firing report from Dave Nordling can be found here.

On April 2nd, LAPD CSP sponsored an event with STRIVE featuring Baby Bertha launches, a high-power launch, and one zinc-sulphur alpha. Maintenance of the MTA site was also performed that day by USC RPL and RRS president, Dave Nordling. A firing report from Dave can be found here.

The RRS executive council for 2022: from left to right, Larry Hoffing (treasurer), Frank Miuccio (vice president), Dave Nordling (president), Keith Yoerg (secretary)

UPCOMING MTA EVENTS

April 14th-15th the UCLA Rocket Project plans to use the Dosa Building at the MTA in preparation for a launch from our neighbor FAR on 4/16/2022. We are requiring that the group complete some site maintenance by way of brush clearance to help reduce the risk of fire at the MTA in exchange for use of the Dosa Building.

On April 23rd, USC RPL intends to static fire their Earthshaker 4 solid rocket, as well as launch a 6-inch rocket called Jawbone from the MTA. The group has been working with Jim Gross, who will be the pyro-op in charge that day. USC has also been conducting repairs on the concrete pad below the vertical test stand, including anchor bolt removal, concrete patching, and installing a new, larger female anchor bolt pattern via a template for accurate placement of future projects from any team.

The University of Michigan (MASA) is planning to conduct testing at the MTA from May 6th – 13th. Mutliple pyro-ops from the RRS will be required to support the campaign that the students hope to complete. The TRR is 4/21/2022, pyro-ops who are available should reach out to the RRS President to request the meeting details at: president@rrs.org Cryogenic deliveries to the MTA through Linde in Lancaster have been resolved, which was an important step considering the difficulties from the last time MASA tested at the MTA.

Frank and Larry have been teaching another rocketry class, this time with the YMCA. This class also uses Big Bertha launches and will likely include an alpha launch as well. This launch is planned for May 21st.

In early June, UCLA Senior Capstone project will use the MTA to launch rockets they have been building.

OTHER ITEMS

  • New and improved website coming soon!
  • Two new members of the society joined the Compton Comet team, Drake Perason and Alexis Monitel
  • Reminder for all pyro-op’s to renew their licenses with CALFIRE using new online system, deadline 6/30/22
  • Quarterly Amazon Smile disbursement

SAFETY AND RISK MITIGATION

Richard Dierking requested info on eye-wash station or similar on-site safety shower. Richard is researching and will present to the executive council in a few weeks.

Example of a portable eyewash station from an RRS member on the meeting

Richard Garcia did research on flame stacks, and whether the RRS should require their use when methane is used at the MTA. He is working on building reference to know what safe distances should be based on existing plume models. As the RRS Director of Research, Richard may draft a paper to add this information to the RRS member library. Other members or student groups with papers they would like considered for addition to the library can contact Richard at:

research@rrs.org

NEXT MONTHLY MEETING

The next RRS monthly meeting will be held virtually on Friday, May 13th 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.

March 2022 virtual meeting

by Keith Yoerg, Secretary, Reaction Research Society


The society held its monthly meeting for March on Friday, the 11th, at 7:30pm by teleconference.

The following items were on the agenda.

  • Chris Lancaster’s presentation on rocket bikes and drag racing history
  • Review of recent MTA events, USC RPL static fire
  • Upcoming events at the MTA
    • Delivery of new 40-foot storage container by Dimitri Timohovich
    • Site maintenance and upgrades
    • Wolframe Blume’s next flight of the Gas Guzzler
    • Bill Inman’s testing for steam rocketry
    • Low power launches
  • Upcoming university event requests and inquiries
    • USC RPL static fire and flight
    • University of Michigan, MASA in May 2022
    • UC Irvine and Cal Poly Pomona
    • UCLA
  • Student classes and launches
    • LAPD CSP – STRIVE event, 4/2/2022
    • YMCA classes, launch on 5/1/2022(?)
  • RRS post office box, renewal and other options

We spent the majority of our time on the subject of early rocketry in drag racing and rocket bikes. Chris Lancaster of Pennsylvania spent an extraordinary amount of time researching this subject and the specific rocket bike built by Henk Vink now on exhibit in Germany. A stand-alone article on this topic may be forthcoming.

Henk Vink, racing a rocket-powered motorcycle in Europe

The MTA firing report from 3/12/2022 covers the events from that day following the meeting. The anticipated events were discussed at the meeting.

The RRS will continue to keep our post office box in Los Angeles (Inglewood) 90009 for another year. The annual cost has been rising but it remains well used for correspondence.

Reaction Research Society; P.O. Box 90933; Los Angeles, CA, 90009

Our director of research, Richard Garcia, agreed to investigate LNG safety guidelines with regard to flaring of this volatile fuel in amateur rocketry applications. He will submit his findings to the council for internal peer review. The RRS will be creating a policy on this issue as some amateur liquid rocket projects intend to use natural gas (largely methane).

example of an industrial-scale flare stack

Further updates to this meeting report are forthcoming.

Next meeting will be April 8th. For those interested in attending, contact the RRS secretary.


MTA Firing Report, 2022-02-05

by Dave Nordling, President, Reaction Research Society


UCLA Rocket Project conducted a static fire test series at the Mojave Test Area on February 5, 2022. i was the pyrotechnic operator in charge for the event. Bill Inman of the RRS was also present as my apprentice in overseeing operations leading to hot-fire that day. UCLA returned with improved launch control and instrumentation boxes. They also invested in plastic tube mounting fixtures for cleaner routing of their low pressure plastic pneumatic lines.

New launch control and instrumentation boxes.
Cryogenic liquid cylinder mobile cart used to place the vessel behind the vertical test stand frame

UCLA had three liquid engines prepared for testing which was a very aggressive goal. Some problems occurred in ethanol fuel tanking operation which resulted in a minor spill. Ethanol is volatile and very flammable, but dissipates quickly and doesn’t pose a lasting hazard or contaminant.

The issue was partially with the procedure lacking precise metering of a prescribed volume and part with a lack of coordination between the teams. Fuel loading is not considered one of the more challenging tasks but even simple items can cause serious problems if the team fails to keep their focus, The RRS has recommended UCLA reconsider and revise their procedures as needed but also to take a wider view of what operations are in place and who is doing what, where and when. Coordination is a full time job requiring diligent leadership and responsible participants,

Ethanol fuel transferred to the propellant tank by a low-pressure gas supply while the tared vessel is wieghed on a scale.

The first engine in the series was a modified version of a prior impinging injector used in last year’s flight. The team was able to complete propellant loading and retreat back to the blockhouse for pressurization operations. All proceeded well until the last part of the countdown.

Ignition failure scrubbed the first firing attempt as the F-sized rocket motor lit but propelled itself downrange pneumatically under excessive pressure built up enough to eject the fixture off the engine before the team could commit to firing. Per UCLA’s procedures, the spotter correctly indicated ”no fire” which caused the launch team to safely abort the sequence. The team held on the release of the pressurant and opted to remotely relieve the system as allowed in their plumbing design after the umbilicals were released. As there was no remote means of draining the LOX, the pneumstically actuated vent was left open to allow the LOX to boil out and with sufficient time elapsed the team was able to approach.

View of the clamshell fixture holding the igniter before the first attempt on the first motor,

The 3D-printed clamp-on fixture that held the igniter was examined and reassembled. The decision was made to drill large vent holes in the plastic two-piece clamshell which would help in the next firing attempt. Unfortunately, the second firing attempt failed to achieve ignition. This time, the spotter did see and hear the F-sized hobby motor fire but the igniter was not energetic enough to light the initial propellant streams. The LOX and ethanol streamed from the engine during the blowdown period and quickly evaporated without fire or explosion. This is a potential failure mode that all liquid hot-fires must plan for. Ethanol and liquid oxygen do not contaminate the area and are quickly dissipated but a chilled pre-mixture of fuel and oxidizer is quite dangerous.

The modified igniter holding fixture with added vent holes.
UCLA removing the first engine and associated vehicle systems mounted to their vertical frame.
Facility connections being made as the mobile test stand is put in place.

Duringn the hardware switch, we had some discussion about different methods of ignition including automotive diesel glowplug systems and high-voltage stungun transformer cells all powered by 12-volt battery or capacitor-based small power sources, Both would require significant development and only a test with cryogenic propellant would be a fair test of these devices. UCLA had some interest in exploring these options but it would have to wait to the next academic year.

I discussed UCLA’s methods of scrubbing their test and recommended they put in a safer means of draining their LOX and ethanol in future operations. This will be discussed before subsequent tests at the MTA.

UCLA has had good results from pyrotechnic igniters using cut-down lances, but these are not easy to acquire as they are ATF-regulated. UCLA decided to try hobby rocket motors which had problems in this first engine test series. The only option forward was to continue using the vented fixture fitted for F-motors and a hope a prior ignition failure did not occur.

With the mobile test stand in place, the second engine tested was the injector design that will fly on UCLA’s rocket. It is the same one used lsst year which worked well. The first injector was unable to be tested that day due to ignition problems and UCLA’s decision to proceed with the second engine as their backup. Time was becoming short as the late afternoon arrived and UCLA had to switch over to their mobile testing rig which would hold the second and third engines when tested.

Second engine being put into the mobile stand,
Preparations for the second engine hot-fire run out to sunset,
UCLA in the blockhouse for final checks before firing

Liquid oxygen quantities in the cylinder ran low and full oxidizer tank load wasn’t possible for what would be the last test of the day. After finishing the LOX tanking, UCLA retreated to the blockhouse for final checks before second firing. No igniter problems were seen with this second engine, but it was a possibility given the recent problems with the first test series.

Hot-fire of the second engine by UCLA.

The hot-fire went to nearly full duration but the burn likely finished fuel rich. Some buzzing was evident so UCLA will review the data to see if the same instability seen in prior firings was present. It didn’t seem to be damaging and if the performance is still sufficient UCLA should have at least one good engine to fly in May when they try to surpass the university-built liquid rocket altitude record.

UCLA posed for a photo after the hot-fire and just before the lengthy teardown in the cold hours of the evening.

The third engine was left for a later test date. UCLA is considering another hot-fire series but only after a full review of the data from February 5th.

My thanks to fellow RRS member, Bill Inman, for making the long drive from Carson City, Nevada to support this test.

Also, a big thanks to Eric Beckner of Friends of Amateur Rocketry for staying late and handling the return of the liquid oxygen cylinder.

The RRS is glad to support university teams with our unique facilities at the Mojave Test Area (MTA). Contact the society at ”president@rrs.org” for those interested in similar projects.