July 2019 meeting

Dave Nordling, RRS Secretary


The RRS held their monthly meeting on July 12, 2019, at the Ken Nakaoka Community Center in Gardena. We had a very large turnout with over 26 people coming in to see the three different presentations we had and catch up on the latest news.

After our reading of the treasury report, we had a special announcement of the induction of five new administrative members to the RRS. Our society is growing and this is in large part to the great participation we’ve been having and the dedication of the many talented people at the RRS.

Larry Hoffing gave us a short summary of the UCLA Rockets project he supervised at the RRS MTA. This Wednesday, July 10th, event was the first since the pair of earthquakes that rattled the nearby town of Ridgecrest in the Mojave. The RRS is happy to report none of our structures had any significant damage and the MTA is very much ready to operate.

We next discussed the upcoming launch event at the MTA tomorrow with Operation Progress in Watts with the LAPD CSP. We’ll have several alphas and a beta launch. We also plan to have an alpha with a parachute recovery system put together by new member, Kent Schwitkis and his friend Brian.

RRS vice president, Frank Miuccio, has started a new educational program this week with the students of Boyle Heights. There will be 10 teams launching their rockets from the MTA in September.

RRS alpha outfitted with a 36-inch parachute
Two alpha payload tubes with the nose cone and couplers installed. Reused parts from recovered alpha rockets.

Our first presenter was Kent Schwitkis who brought several of his students from Compton College to our Friday night meeting. Kent is a member of the Sierra Club and Ski Patrol and has many years of experience with wilderness survival and first aid. His presentation outlined the important of planning for many kinds of potential emergencies. One of the important results from this discussion was the need for the RRS to form a safety committee to begin preparing emergency plans and establish contact with the regional authorities in preparing to handle serious emergencies if the need would ever arise.

Kent Schwitkis and Waldo Stakes before the July 2019 meeting

The second presenter we had at the meeting was Sam Austin, a senior at MIT. Sam presented his two-stage solid rocket design to reach the von Karman line.

Sam Austin (right) presents his booster and second stage design for his solid rocket

Sam also detailed the kerosene-LOX liquid rocket design that was test-fired at FAR in January 2019. Although the test was short (3 seconds), his results were impressive and his injector survived intact..

Sam’s liquid rocket injector which was modified for 1500 lbf of thrust

The last presentation was by RRS members, Jack Oswald and Cooper Eastwood. They have been steadily improving their solid motor design and have fabricated their improved motor based on prior tests. Their goal is to reach the 50,000 foot altitude limit at the RRS MTA on July 20th. His “50 for 50” rocket is 12 feet tall and 5-inches in diameter built entirely from scratch. The launch is to be timed with the 50th anniversary of the Apollo 11 moon landing.

Jack and Cooper detail the progress they’ve made and their solid motor ready for flight from the RRS MTA on July 20th.

The solid rocket holds 30 lbm of APCP propellant with an estimated burn time of 3 to 4 seconds generating an impulse of 7000 lbf-sec. The rocket fully loaded is 84 lbm and should reach a peak acceleration of 30 G’s and a burnout velocity of Mach 2.5 as it reaches 50,000 feet.

A 100-foot drogue streamer will deploy from the recovery system followed by a 9-foot Apollo 11 replica parachute at 2000 feet. The flight events are driven by an upgraded classic flight computer from Eggtimer and an RRC3 dual deployment system from MissileWorks. The von Karman nosecone is 3D printed and the aluminum fin can was rolled onto the aluminum body to be painted in polished black and white pattern of the Apollo 11 vehicle.

The RRS looks forward to the successful flights of Sam and Jack’s rocket from FAR and the RRS MTA, respectively. Both will be on the 50th anniversary of mankind’s greatest achievement on July 20th.

If there are any questions or corrections, please contact the RRS secretary. The next meeting of the RRS will be August 9, 2019.

MTA launch event, 2018-06-02

The RRS held a launch event at our private Mojave Test Area (MTA) with the students and staff of UCLA on Saturday, June 2, 2018. The event was overseen by our pyro-op, Jim Gross, with me serving as his apprentice. It was a good day for rocket launching despite the 100 degree temperatures that day. The winds were very low and almost still at certain times.

The horizontal thrust stand was fit checked at the RRS MTA concrete slab. All footplate holes aligned with the 1/2″-13 female anchor bolt holes. The load cell blocks mated up to the adapter plates. Concern was raised about the horizontal stability “wagging” of an alpha rocket if it were fired in the adapter as is. Osvaldo started a design to create an extension on the thrust stand which will better retain the rocket from excessive side loading.

RRS horizontal thrust stand passes fit check at the MTA, new primer coating added for rust protection

UCLA was completing a quarterly course in rocketry which featured the hard work of five student teams building their own amateur rocket using commercial F-class motors of different types.

UCLA students pose at the RRS MTA on June 2, 2018

The RRS was able to inspect each one of these model rockets and ask questions of the team members about its construction and the unique aspects used in their payload and vehicle design. Each of the teams ran flight stability tests at the UCLA wind tunnel to validate their design. Each rocket was fired from a rail launcher and a commercial firing circuit under the supervision of the pyro-op.

Six rockets from five teams at UCLA on display in the group photo (6/2/2018)

Before the flights of the student rockets, a test rocket was flown to check the wind speeds. Results showed low winds so the team flights proceeded. The winds at the launch site in the desert were very low throughout most of the day.

UCLA’s demo rocket to test winds before team flights.

UCLA prepares their custom rail launcher for their model rockets

One team attempted a two-stage rocket using a D-class motor in Stage 2. Results from all rockets were largely good. All were recovered and some were able to be relaunched.

UCLA’s Team Sharky prepare their rocket “Bruce” for his maiden voyage.

Each rocket flew an egg as a payload with a parachute recovery system. Each rocket also included a commercial altimeter chip which relayed the results to display on a cellphone application. Altitudes ranged from 1600 to 2400 feet.

UCLA also was static testing a hybrid motor adapted from commercial products to a design of their own. Two vehicle systems were built and alternately tested with replaceable HTPB-based fuel grain modules. UCLA brought a few nitrous oxide tanks to replenish their oxidizer supply. All seemed to go well, but the results were not good enough to proceed with a flight test as originally scheduled.

Dr. Mitchell Spearrin and Jim Gross oversee the hybrid rocket static firing procedure at the RRS MTA, 6/2/2018

UCLA’s Anil Nair prepares the hybrid motor for static firing at the RRS MTA, 6/2/2018

UCLA’s first of three hybrid motor firings, 06-02-2018

Results from first hybrid motor firing left a white residue around the outside of the nozzle

UCLA did buy two of our RRS standard alpha rockets which were custom painted in the blue and gold colors of the UCLA Bruins. At the end of the long day, UCLA opted not to fly their two RRS standard alphas and save them for another flight. The RRS and UCLA discussed flying an altimeter chip in a vented payload tube on the next UCLA flight of the RRS alpha.

Two RRS standard alpha rockets for UCLA

The RRS already had the micrograin propellant mixture ready so we proceeded with a flight test of our own RRS alpha rocket. We had plenty of daylight left in the summer month of June. For those that stayed at the MTA into the late afternoon, the RRS did conduct a first test of a payload recovery system in a standard RRS alpha rocket. This system was built by RRS president, Osvaldo Tarditti.

Jim Gross and Osvaldo Tarditti load an RRS standard alpha with parachute payload into the launch rails

An RRS alpha with its payload being installed.

Instrumented RRS alpha in the launch rack. A manual switch with red flag is used to arm the system before launch. This keeps the battery from depleting while waiting to launch.

The payload timer is started when the rocket lifts out of the launch rails and the pin is pulled out by the yellow wire tied off to the launch rails.

Despite some problems initializing the payload one the first attempt at the launch rack, the rocket was successfully reset, reloaded and flown. The deployment of a parachute from inside an RRS standard alpha rocket’s payload tube with a successful recovery was the only objective of this flight.

In the still winds, the rocket didn’t drift very far from due west and the orange parachute was very visible against the clear blue afternoon skies once it reached lower altitudes. The alpha rocket booster portion was recovered, but the lanyard holding the nosecone and payload segment tore loose on deployment and was not recovered.

Lanyard failure lost the payload and nose with the timer circuit inside, 6/2/2018

Also, the orange parachute did show signs of localized overheating and melting from the 1-gram black powder ejection charge used to deploy the parachute.

scorching of the parachute from the ejection charge; parachute was still effective

The parachute did deploy fully and significantly slowed the descent of the rocket booster. With the low winds, the rocket did not drift very far downrange and was easily recovered 50 feet from the roadside going out west from the MTA

Osvaldo kneels behind his RRS standard alpha parachute system successfully flown at the MTA on 6/2/2018

I took several photos of the assembly and loading process. Osvaldo has promised to explain the full details of his parachute system and deployment timer. The RRS will definitely reattempt parachute recovery with our alphas and hope to fly again at the next event.

As a final step, we make sure to burn off our residual propellants. Jim Gross set this up near the launch pad and used the firing system already in place at the bunker.

Pyro-op Jim Gross prepares to safely dispose of residual micrograin propellant at the RRS MTA

Residual micrograin propellant safely burns up at the end of the day

At the end of the propellant burn-off, the smoke cloud lazily lingered as it rose away from the site. Taking several minutes to do so, this was a very visual reminder of just how favorable the winds were that day.

minutes later, a spent micrograin propellant smoke cloud slowly drifts away in the low winds at the MTA

If there is anything I have missed or misstated, please let me know.
secretary@rrs.org

The next monthly meeting is this Friday, June 8th at 7:30PM. Discussion of the UCLA event and our next event with LAPD CSP will certainly be on the agenda.