Tag Archives: pyro-op

MTA Launch Event, 2022-06-04

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By Dave Nordling, President, Reaction Research Society

The RRS held a launch event on Saturday, June 4, 2022, at our Mojave Test Area (MTA). I was the pyro-op in charge. Winds were brisk and steady, but still under the 25 MPH limit. We had two operations that day.

The first was the UCLA Senior Capstone project led by Professor Brett Lopez. This quarterly class has seniors build and balance their own rockets from scratch. They load F-sized motors and fly them at the end of the quarter to prove their team’s skills in flight.

The UCLA students gather their materials in the propellant loading area.

Secondly, RRS member Wolfram Blume returned to the MTA with the latest rebuild of the Gas Guzzler. He had concerns about flying in the strong winds that day so he limited his work to testing the staging system with both halves on the 1515 rail. Bill Inman and new member, Dale, offered their assistamce in positioning the rocket on the rail.

Dale, Wolfram and Bill Inman

Bill Inman and Dale assisted Wolfram in trying out the new staging system in the Gas Guzzler. The old system (e.g., last December) was a hassle and required assembling the upper stage (main body tube, cowling, nose cone) on the rail with a screw driver and a step ladder. The mating of the booster thrust rods into the upper stage was very difficult. So after December, he redesigned and rebuilt the thrust rods and the staging system. The result was a successful design. The new system is fairly easy to stage on the rail, does not require any assembly (with the ever-present danger of losing small screws) and does not require a ladder. Wolfram feels good about this system for future launches.

The Gas Guzzler during its fit check on 6/4/2022

Wolfram doesn’t think he’ll make it back to the MTA until the summer heat is over. His goals for the summer both involve the fuel system:

  • The flameholder is the ramjet needs to ignite every time.
  • The ramjet slows down very quickly after stage separation (25m/sec/sec = 60mph/sec), so the ramjet must ignite within less than 2 seconds after stage separation; less than 1 second would be better.

Using the 270-volt, 3-phase electricity at Wolfram’s laboratory, he can run a 20hp air blower which can mimic the air flow at stage separation with a K-motor in the booster (175 m/sec). The blower can be run higher to mimic stage-separation flight speeds of about 250 m/sec which is just below the separation speed of an L-motor in the booster (280-300 m/sec).

Wolfram’s workshop is good for the tuning and testing the flameholder. but running the main burner would require returning to the MTA. The main fuel flow could be tuned using water. After the summer’s heat is over, he will return to the MTA and finish testing the parachute system. The first powered flight of the ramjet with a short – 5 second burn is under discussion.

This short event was also a good time to clean up the site a bit. The society has big plans for the summer including some much anticipated facility upgrades.

The next monthly meeting will be June 10th (2nd Friday of each month) by teleconference. Contact the RRS secretary for details.

MTA Firing Event, 2022-04-02

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by Dave Nordling, President, Reaction Research Society

The RRS held a launch event at the Mojave Test Area on Saturday, 4/2/2022. Larry Hoffing was our pyrotechnic operator in charge. It was a very pleasant day with low winds for most of the day.

The sign arch welcomes people to the Mojave Test Area

It was also the first time in a long time that all four members of the executive council were present at the same event. We took the opportunity to capture the moment in a photograph.

The executive council for 2022; Keith Yoerg (secretary), Dave Nordling (president), Larry Hoffing (treasurer), Frank Miuccio (vice president)

The primary project for that day was the launch of 15 Baby Bertha rockets made by the students of Nickerson Gardens over the six-week educational program the society held with the support of LAPD CSP. The rockets give the students a tangible sense of accomplishment and seeing them in flight from the MTA gives them good memories of what hard work can do.

The newest armada of Baby Bertha’s ready for flight.
Students wait in the Dosa Building before the launch.
The launch rails made ready for the event.

There was an RRS standard alpha made for this occassion which flew at the end. It was prepared by our experienced pyro-op, Larry Hoffing, and made an impressive finish to this school event.

Larry Hoffing (right) trains his colleague in the assembly and loading of a micrograin alpha rocket.
Larry Hoffing oversees the launch rail with Keith Yoerg for an alpha launch.

Secondarily, we had a few members of the USC RPL team out at our site to begin repairs of the concrete pad area used in their static fire tests. Removal of the male anchor bolts in USC’s custom mounting pattern were finally distorted too much to be useful. They were a frequent tripping hazard and their removal was a blessing.

USC RPL cinducts repairs of the vertical test stand pad.
USC RPL team at work making improvements at the MTA.

Also, the USC RPL team made several contributions to improving the MTA site with earthwork, brush clearance, and just good old fashioned hard work. We’re grateful to them coming out to help keep the site in good shape,

Earthwork in progress to backfill the erosion.
View from the blockhouse of the Peregrine rocket ready for launch.

The last portion of the day was spent launching a few more model and high-power rockets before the winds became too high. We used the time to plan our next event and rearranged our materials in our new storage container.

Our next monthly meeting is Friday, April 8th. Contact the RRS secretary for information.

secretary@rrs.org –

March 2022 virtual meeting

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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.