Tag Archives: UCLA Project Prometheus

MTA launch event, 2021-05-29

Posted on by

by Dave Nordling, Reaction Research Society

The Reaction Research Society held a launch event at the Mojave Test Area mainly to support the UCLA Prometheus team for a static fire test of their high powered hybrid motor. UCLA chose one of the largest nitrous oxide hybrid motor designs, the M1575, made by Contrails Rocketry. Dave Crisalli was the pyrotechnic operator in charge for this event. I was his apprentice for the hybrid static fire.

There were three main activities at this event. The first was the UCLA Rocket Project making their preparations to launch their ethanol and LOX vehicle from the Friends of Amateur Rocketry (FAR) site from the 60-foot rail. FAR is just to the south of the RRS MTA where the UCLA Rocket Project had twice in one day static fired their 750 lbf liquid propellant rocket engine just four weeks earlier on 05-01-2021.

Weather conditions were ideal with winds being nearly still for most of the morning. This makes little difference for the hybrid motor static fire testing at the RRS MTA which was the second project by UCLA. Wind would factor heavily in the flight of the UCLA’s liquid rocket.

The third planned activity for UCLA was a series of model rocket flights from several high school teams mentored by UCLA graduate and undergraduate students. Still winds made for easier recovery of the first rockets launched that day.

UCLA Prometheus team prepares for static fire at the RRS MTA on 5-29-2021
Dave Crisalli gives the MTA safety briefing for the event in the loading area where the model rockets were assembled for flight.
UCLA graduate students conducted the model rocket launches from just west of the large test stand at the MTA

UCLA at the end of each Spring Quarter conducts a launch event where student groups build small rockets with egg payloads using single and dual-stage vehicles with model rocket class motors (G and under). UCLA graduate students and Professor Mitchell Spearrin were leading this event.

It is good experience for beginners and experts alike to build and fly model rockets., The RRS has it’s own such internal program called the Yoerg Challenge which is to motivate all members to build and fly a model rocket kit at least once from the RRS MTA. The RRS is known as an experimental society and not limited to the model rocket code, but we are also fully supportive of all forms of propulsion as long as it is safely conducted and compliant to the regulations set by the state of California.

As the UCLA hybrid rocket team was making their system checks, they discovered a problem in their nitrous filling system and valve commands. During this diagnostic period, some of the RRS members went to the nearby FAR site to see how the UCLA liquid rocket preparations were progressing.

UCLA’s liquid rocket set on the 60-foot rail launcher at FAR. The team preparing the vehicle for erecting, loading then flight.
RRS members from left to right, Bill Inman, Waldo Stakes, John Wells and Manuel Marquez, inspect the UCLA liquid rocket on the 60-foot launcher deployed at the FAR site.
A few last minute fixes and the rocket was made ready.
The liquid rocket sits on the rail before raising it for launch.
UCLA’s rocket is in position getting ready to clear the area for propellant loading and pressurization operations.

Some of the RRS members remained at the FAR site to witness the launch. After two years of design, planning, build and world pandemic, the UCLA team liquid rocket launch was an amazing success. Due to the relatively low winds that day under clear skies, recovery was made just under a mile away. Preliminary data from telemetry confirmed a new university team altitude record of 22,000 feet. It was an amazing sight to witness from the observation bunker at the RRS MTA.

UCLA’s liquid rocket had a perfect launch on 5-29-2021 setting a new altitude record of 22,000 feet by a university team. Photo by Xavier Marshall, RRS.

The UCLA Prometheus team had corrected their initial electrical problem and began the series of procedural checks to familiarize the new members of the hybrid rocket team. Some minor adjustments of the motor mount alignment was necessary before getting into test.

The UCLA Prometheus team makes some adjustments to better align the hybrid motor in the vertical skid mounted to classic I-beam at the RRS MTA.
The nitrous oxide K-bottle sits inverted in the sloped stand to allow the liquid to flow from the port. Some nitrous oxide bottles come with an internal siphon line to avoid having to invert the container. The bottle is also being chilled with ice to keep the oxidizer sufficiently dense and improve performance in hot-fire.
The top bulkhead of the hybrid motor is attached to the load cell for thrust measurement. A pressure transmitter is tapped into the nitrous oxide volume to further gauge performance.
The high-powered hybrid motor by Contrails uses four 1/4-inch fill lines and a single smaller vent line from the same floating injector at the mid-point inside
Dave Crisalli (right) inspects the hybrid motor on the test rails before the firing
UCLA Prometheus team tracks their written procedures as they progress to hot-fire in the old blockhouse.

The hybrid motor firing proceeded without further problems and resulted in a spectacular test meeting expected performance. Continuous thrust levels over 600 lbf were recorded but data analysis is still ongoing.

The hybrid motor at startup.
The UCLA hybrid motor at full thrust. Chamber pressure was over 1000 psia.

The team had a second hybrid motor grain ready for another firing so they proceeded with disassembly and inspection of the parts. The floating injector seals were still in good condition but the graphite nozzle having survived many prior hot fire tests did not survive that day’s test. Although the throat was in good condition, the inlet taper had cracked requiring a replacement the team did not have.

The top half of the floating injector with its internal siphon tube protruding up to near the top bulkhead.
The floating injector being removed from the lower half containing the spent fuel propellant grain.
The floating injector was removed after hot-fire and the dual O-ring seals were inspected. Seals were ok for re-use.
The nozzle assembly did not pass inspection after the first and only hot-fire on 05-29-2021.
The graphite nozzle fractured at the inlet taper from the first and only firing that day.

UCLA Prometheus was pleased with the results from the single firing and will proceed with integrating the motor into their flight vehicle for a launch from FAR on June 19, 2021. The RRS will hold an event at the Mojave Test Area on this same Saturday for member projects and will observe the flight from our northern vantage point.

UCLA avionics team conducted a few tests on the GPS tracking module that will fly on their vehicle in June 2021.

In the last hours of the day, after most of the UCLA liquid and hybrid teams had cleared the area, packaged and carried away their trash, packed their equipment and departed the RRS MTA and FAR sites. The UCLA avionics team remained at the MTA to conduct another series of tests on the GPS tracking system. The society was glad to support this diligence which will help assure success in one of the most important aspects of rocketry which is data acquisition from telemetry. If there is no data, it didn’t happen.

For any group interested in using the RRS MTA for their propulsion related projects, download one of our Standard Record Forms from our RRS.ORG website and submit this request to the RRS president. The society has had a long relationship with UCLA and USC, but we are also supportive to any amateur, professional or academic groups wanting to learn from test.

president@rrs.org

MTA launch, 2020-02-22

Posted on by

by Dave Nordling, RRS.ORG

The Reaction Research Society (RRS) held a launch and static fire event for three UCLA teams and one of our own RRS teams at the Mojave Test Area (MTA) on Saturday, 2/22/2020. Poor weather was a persistent threat from the day before with light rains coming and going from the early morning hours and even throughout the launch day. Winds calmed just enough for a successful rail launch of UCLA’s solid rocket motor. Fortune favors the bold and this proverb did not disappoint our participants that day at the MTA.

Rain clouds still filled the skies on a very calm morning. Preparations began for UCLA’s solid rocket motor launch from our rail.

With the liquid and hybrid rockets, Osvaldo Tarditti, our RRS president was our pyro-op in charge. I served as his apprentice for this event as part of building my experience for becoming a pyrotechnic operator 1st Class. This was the second of two apprenticeships I have served under two first class pyrotechnic operators. Osvaldo gave our safety briefing to all of our attendees that day before beginning the scheduled events.

UCLA gathers around to hear our safety briefing. Most have been to the RRS MTA before but we give the briefing each time to reinforce good practices.

UCLA had three projects ready for flight or static-fire at the MTA. The first was the solid motor driven rocket built by the UCLA Project Prometheus team. They were using a commercial K-sized motor with a vehicle equipped with a downward-facing camera built into the lower body.

UCLA’s Project Prometheus built a rail-launched rocket with a commercial solid motor.
The Gerald Ticonderocket in the color scheme of a common wooden pencil.

Elizabeth, the UCLA team leader for this solid rocket project assisted me with the launch preparations. The rail launched rocket worked perfectly and the recovery system operation was visually confirmed as it descended to the west of our launch site.

My 2-1/2 inch rocket with a commercial H-222 hybrid motor from Contrails Rocketry. The body has been extended for better packaging.
The motor has been successfully loaded into the body tube complete with retainer. All that remains is to complete the recovery system packaging and find our next opportunity to launch.

Larry, Osvaldo and I have made progress on improving the 2-1/2 inch rocket with a commercial H-sized hybrid motor. Larry made an extension on the payload tube to fit all of the recovery system more easily. We have the Contrails H222 motor fully integrated and ready for loading.

The RRS reloaded and refurbished our nitrous bottle and valve manifold, but we didn’t get to loading operations.

Our nitrous bottle was refurbished and reloaded for the testing and we successfully conducted a valve test of the manifold that verified that our control box works well. We were reworking the black powder charge and repacking the parachute when the weather shifted and the winds picked up.

Weather changes quickly in the desert. Our smaller rocket missed our window for launch that day.

The weather was perfect 15 minutes earlier with the launch of UCLA’s solid motor, but at the time we were discussing launch of our hybrid motor it became clear the weather would be getting worse and winds too strong for launch of a smaller rocket such as ours. Since the RRS will be returning to the MTA site on Sunday, March 1. We figured we would do some minor improvements to the payload packaging and try again when we are fully confident and hopefully with better weather for the flight.

The hybrid motor is secured to the RRS I-beam. This is one of the very first assets of the society which predates our arrival to this MTA site.
UCLA hybrid rocket team making load cell adjustments on their thrust stand before hot-fire.

UCLA’s hybrid rocket team under the same name, Project Prometheus, sought to static fire a commercial M-sized hybrid motor as part of getting ready for a flight later this semester. They secured their test stand vertically to our historical I-beam location which was the original article from even before the RRS moved to the current MTA site in 1955. The RRS was glad to assist UCLA in securing to this location and making ready for nitrous oxide fill operations then ignition for static fire measurements.

Hot-fire of the hybrid motor took place around 5pm which by all appearances was a success. The motor case was intact and post-flight assessments looked promising, but an error in data acquisition resulted in no thrust measurements being recorded despite successes in pre-test checkout. UCLA is considering re-attempting this testing at the RRS MTA very soon.

UCLA working on their liquid rocket’s pressurant system.

The last of the three projects would be the static fire of the liquid rocket for Project Ares. The liquid rocket team mounted their hardware to the vertical test stand simultaneously as the hybrid rocket team mounted to the I-beam thrust stand. Both teams worked hard to be ready before the other but in the end, the liquid rocket took longer to be ready.

This would be a second attempt to static fire their liquid rocket system from 2/1/2020 at the RRS MTA. UCLA had been finding and fixing leaks in their pressurization system in the weeks leading before this test.

Making some preliminary checks before commencing liquid oxygen tanking of the rocket.

They proved their fixes before departing to the RRS MTA, but again ran into problems with leakage in the pressurant system. After several more repairs and discussion with the team and pyro-op in charge, the decision was made to proceed. All other systems had passed checks and the leak rates measured were consistent and would only reduce the burn time while assuring safe engine hot-fire.

UCLA begins the final operations following their proven checklist.

Around 5:30pm in the last light of that long day, UCLA’s liquid rocket was proven in a brilliant, steady and powerful hot-fire of their ethanol-LOX propellant liquid rocket. It was an exciting time which showed reasonable thrust results that led UCLA to conclude that the testing that day was sufficient to proceed with flight vehicle integration operations for their motor.

UCLA’s static fire on 02/22/2020 was steady and well controlled.
All initial inspections of the liquid motor looked good. Preliminary review of the data was encouraging and will be useful in grounding their vehicle performance predictions.
In the last rays of daylight, all three UCLA teams pose with their project’s pride at the RRS MTA vertical test stand.

UCLA did a great job of cleaning up at the site. They also returned the LOX dewar back to the nearby Friends of Amateur Rocketry site. We’re thankful to everyone who made this day a triple success. Our next launch event is scheduled for March 1st. We’ll also discuss this and our other recent MTA events at the next RRS meeting on March 13, 2020.