by Dave Nordling, President, Reaction Research Society
The University of Southern California (USC) Rocket Propulsion Laboratory (RPL) conducted a series of six propellant sample burns for characterizing their latest mixture. I was the pyrotechnic operator in charge for that day. New member and former USC RPL student, Michael Rouleau, was my apprentice that day.
Careful installation of the grains.
Testing took place in the horizontal configuration on our repaired pad with the new 3/4” female pattern using a load cell and chamber pressure transmitters reading from the bulkhead in a modular nozzle can configuration.
USC RPL has had several motor failures in recent times which has led this year’s team to try a better known and safer recipe. COVID-19 played a role in creating a knowledge gap. This year’s team hopes to reclaim a success when the full static fire motor is tested at the RRS MTA in a little more than a month.
The Reaction Research Society held our monthly meeting on September 9th. It was the first in-person meeting in 31 months We met at the front office of the Compton/Woodley Airport at our usual starting time of 7:30pm. This was a new location for us and we are grateful to the staff of Los Angeles County for their hospitality.
We still held our teleconference which continues to allow our members living far from the city to join us. We will stay at this location for the next two more meetings to decide if this will be our permanent location.
September meeting agenda
Review of recent MTA/rocket events:
Upcoming MTA events
Bathroom work to continue this month
New concrete launch pad
USC RPL testing campaign
Catching-up in person
This is a placeholder until the full meeting minutes can be transferred.
Our next meeting will be on October 14 at the same location at the front office of the Compton/Woodley Airport. We will meet every 2nd Friday of each month. Contact the RRS secretary for information.
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.
