MTA Launch Event, 2021-04-10

by Keith Yoerg (RRS Secretary)


The RRS held a launch event at our Mojave Test Area (MTA) on April 10, 2021, the day after our monthly meeting. COVID-19 still remains a threat so everyone continued to observe protective protocols – masks & physical distancing. For the first time in months, we had a day with great weather for launching rockets and we made the most of it! We had low-power, high-power, and experimental solid rocket launches, another launch of Bill Inman’s Solar Cat, the maiden voyage of Wolfram Blume’s Gas Guzzler, and a static fire of Larry Hoffing’s solid power motors. Osvaldo Tarditti was our pyrotechnic operator in charge.

Activity around 9:30 am at the MTA – prep work ongoing for CTRL+V (left) and Solar Cat (right)

CTRL+V (USC RPL)

Preparation for the first launch of the day: CTRL+V actually began the day before launch with motor integration and other preparation work taking place at the MTA site. On the morning of the launch, the team from the USCRPL installed the rocket on the launch rail, which was then raised into place south of the MTA’s vertical test stand. Wires running from the rail were staked to poles and hammered into the ground to provide additional stability for the rail. Several launch crew members can be seen prepping the rocket above, and a still image of the launch of the rocket can be seen below.

Launch of USC RPL’s CTRL+V, the smoke took a strange path up the rail faster than the rocket!

The rocket flew on a 6″ experimental rocket motor. A specific procedure was followed prior to launch, under the supervision of the pyro op, which included radio go/no-go call outs from several teams including tracking, avionics, and even a drone that took footage of the launch! All spectators and crew were in the bunker during takeoff at 11:04 am – ignition was prompt and rocket left the rail quickly and cleanly. The initial telemetry reported by the team indicated an altitude of over 11 km. Several members then went off on the daunting task of recovering the rocket from wherever it landed.

LUMINEER (BPS.space)

The next flight of the day came from BPS.space with the rocket Lumineer. This launch was conducted from one of the pads just west of the vertical test stand. The flight took place around 1:20 pm on a commercial Cessaroni “N” motor and was livestreamed to a reported 9,000 viewers on YouTube. The rocket utilized a “fly-away” rail guide to provide stability and eliminate the drag of rail buttons, which can be seen still in the process of falling from the rocket in the image below. The target altitude was 10 km, but telemetry was lost shortly after takeoff so the actual peak altitude was unclear after launch, and the rocket was not recovered for some time.

Launch of Lumineer from BPS.space

GAS GUZZLER (Wolfram Blume)

Wolfram Blume has been diligently making the pilgrimage to the MTA events over the last several months and the weather has been uncooperative for his chances of launching, but that finally changed in April! The maiden voyage of the Gas Guzzler took place from the pad just west of the vertical test stand. This flight was conducted to answer several questions about staging during the flight – so the ram jet second stage was flown empty and only the first stage, commercial solid rocket motor was used to power the rocket. A slow-motion (10% full speed) video of the launch can be seen here.

Launch of Wolfram Blume’s Gas Guzzler, it’s so calm the flag on the vertical test stand isn’t waving!

The ascent of the rocket was smooth, validating the rigidity of the rocket’s design and the stability when empty. The data from onboard altimeters confirmed that the ram air entering the 2nd stage was enough to separate the 2 stages immediately (0.1 second) after motor burnout which occurred at 1,440 ft. The parachute for the booster stage deployed successfully and that stage was recovered without damage. The ram jet, upper stage utilizes a dual-deployment of a drogue parachute at apogee and main parachute at 1,000 ft above the ground. While each of these deployments were successful, the main parachute did not pull out of the deployment bag so the stage landed hard and damaged a few parts. Fortunately, the 2nd stage is not the final parts intended for the full flight of both stages so there will not be delays to the project to rebuild. Wolfram collected lots of useful data and plans to add a GPS tracker and other upgrades before his next flight. We all hope the weather remains in his (and all of our) favor!

CHARLIE HORSE (Keith Yoerg)

Up next was the 12th flight of Keith Yoerg’s rocket Charlie Horse. This was the first flight test of the LoRa GPS tracking boards discussed in previous reports. There are several difficulties with getting the units setup properly, not least of which being the frequent firmware updates required to pair the board with the mobile phone app (2 updates in as many months). Powering up the boards the night before would have helped eliminate these struggles, but a successful launch was still completed, a slow-motion (10% full-speed) video of the launch can be seen here, which was on a commercial Cessaroni I280-Smokey Sam motor.

Keith Yoerg’s Charlie Horse seen through the smoke of launch – the camera was tipping over!

One issue still to be resolved with the LoRa trackers is a setting within the Meshtastic mobile application which trades off tracking range for the speed at which new information packets are sent. The “medium” setting was used on this flight but for rocket flights it may be advantageous to reduce the range (which is purported to be up to 10 miles) in favor of more frequent location updates. More testing will be done on future flights in hopes of developing a cheap, simple GPS tracking available for rockets flying at the RRS.

SOLAR CAT (Bill Inman)

Bill Inman’s solar-heated steam-powered Solar Cat rocket took to the skies around 4:31 pm. While the weather was perfect for most of the projects, the light overcast that can be seen in the pictures above proved problematic for the solar heating required for the best flight. In addition by launch time, the solar collector was at its westernmost limit so no more heating was possible. At launch the water temp was 370 F and was at 130 psi.

Bill Inman’s Solar Cat takes to the skies for it’s 2nd launch at the MTA

The flight reached 41 mph speed and achieved a 60 ft altitude. While this was an improvement on the first Solar Cat launch at the MTA, with additional heating there could be even more impressive stats. While he can’t control the clouds, Bill hopes to arrive at the MTA site the night before a launch in the future to increase the chances ¬†of getting off a good test and launch before reaching our western limit of travel for the solar collector.

THE YOERG CHALLENGE (Dimitri Timohovich & Keith Yoerg)

With this being Dimitri’s last MTA event before leaving to Alaska for the summer, some other RRS members need to step up to the plate to keep the “Yoerg Challenge” alive. I have put out the call for more RRS members to build low-power rockets to fly at the MTA, and have left my 5-pad PVC launcher at the site for future launches. IT’S CHEAP, IT’S FUN, IT’S A CHALLENGE (and everyone is a winner)! What’s not to love? So get out there and build some model rockets!

The remains of the “Space Crater” – not covered in raw egg!

The entrants this month included Keith’s Big Bertha, Baby Bertha, and Hi-Flyer XL rockets and Dimitri’s Space Crater – which carried eggs in honor of Easter this month. Fortunately, Dimitri’s wife had the foresight to hard-boil the eggs because his rocket took the “Crater” part of its name a bit too seriously (the remains are shown above). A few of Keith’s flights before the GoPro battery died can be seen here.

SOLID MOTOR TEST FIRE (Larry Hoffing)

Larry Hoffing had some experimental solid rocket motors ready to test fire, but with all the other activity going on at the site he took the time to install a new “No Smoking” sign on the covered propellant loading area (shown below). Once things were a little less active, Larry was able to affix the motors and perform a test-fire. While the burns were long, they did not produce much thrust and need to be improved upon before use in a rocket.

No smoking sign added to the covered propellant loading area by Larry

CONCLUSION

In addition to everything detailed above, one of the USC RPL members flew a high power rocket to earn her Level 1 certification with the National Association of Rocketry, and Dimitri flew his water rockets with his son.

This was by far the most active event at the MTA in the past year and was an exciting day for anyone who likes to see rockets fly! Our next launch date has not been decided upon, but we hope to have an event in May to continue hosting at least one event per month at the site.

April 2021 Virtual Meeting

by Keith Yoerg (RRS Secretary)


The latest meeting of the Reaction Research Society took place this past Friday, April 9th and had 15 attendees – including another guest presenter. We kicked off the meeting by watching footage of Bill Inman’s Solar Cat launch from March, and a video of a liquid engine static fire from the Georgia Tech Yellow Jacket Space Program, who presented to the RRS about their project last month.

Screenshot of discussion during the monthly meeting

GUEST PRESENTATION – WILSON F/X LAUNCH CONTROLLERS

Brad Wilson from Wilson F/X launch controllers was our guest presenter for this month, continuing our recent discussions on wireless launch controllers. Brad started the company roughly 20 years ago with Dan Fox, after building launch controllers for their local high power rocketry club in the midwest. They began with a wired single pad controller, and have since expanded to build 64-pad systems as well as adding wireless firing capabilities. Their wired and wireless modules are in use by many local rocketry clubs including ROC and FAR, as well as others around the country. The largest motor known to have been flown on a Wilson F/X system was a size Q at a rocket launch in Black Rock.

Richard Dierking modeling the wireless launch module from Wilson F/X

RRS members had a lot of good questions for Brad, who was gracious enough to explain several different features and specifications of his system. Both the wired and wireless Wilson F/X systems use 32-bit encryption to send the firing signal from the control box (where the operator flips the switch) to the pad box (which supplies the current to light the ignition charge). This means the control box is required and the pad box cannot be used by itself to fire the motor. Brad sent along some product specification sheets for RRS members to review. Any member that would like a copy can request one by emailing the RRS secretary at: secretary@rrs.org

EVENTS AT THE MTA

After a brief discussion about the March launch event, the group began planning for the MTA event the day after the meeting. Several members with projects that have become staples at our recent events planned to join for the launch – including Bill Inman’s Solar Cat, Wolfram Blume’s Gas Guzzler, and “Yoerg Challenge” low-power model rockets from Dimitri Timohovich and Keith Yoerg. In addition, Larry Hoffing expects to have experimental motors ready for testing.

A low-power rocket launch near the MTA entrance

2 additional fights are expected – a rocket from the USC Rocket Propulsion Lab flying on an experimental 6″ diameter motor and BPS.space, flying on a commercial N sized motor. A write-up on these activities will be available within the next few days.

LAUNCH COORDINATION BETWEEN RRS & FAR

Rick Maschek joined for the meeting and began a discussion about coordination of launching activities between the RRS and our neighbors at FAR. With activity picking up at both organizations, it’s becoming more common for us to have event scheduled at both sites for the same weekend. Because of the proximity of our launch sites, rockets have been known to launch from one and land near the other.

Both groups are committed to safety when performing rocket activities, and improving communication about launches between on-site personnel in each organization has been identified as a priority. One option suggested is to alternate weekends between the organizations so that events do not overlap. Since weather and other schedule considerations can sometimes make that difficult to implement, it was agreed that radio communication should be established on days when both organizations are operating so that everyone will be aware of impending launches.

YOUTH OUTREACH CLASS

Frank Miuccio updated the membership on the status of the youth outreach programs that the RRS hosts, which seem likely to happen but are more complicated due to COVID-19 precautions. A classroom space large enough for adequate physical distancing has been found, but travel to the MTA site will likely not be possible until more restrictions are lifted.

Because the demonstration of rocket flights is one of the more engaging aspects of the class, Frank has begun developing a class plan that would allow for more hands-on activities without pyrotechnics. Soda straw rockets propelled by air and film canisters propelled by a baking soda & vinegar mixture are 2 ideas being pursued to give the students an exciting achievement until an MTA visit can be safely arranged.

NEXT MONTHLY MEETING

The next RRS monthly meeting will be held virtually on Friday, May 14th 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

March 2021 Virtual Meeting

by Keith Yoerg (RRS Secretary)


The latest meeting of the Reaction Research Society took place this past Friday, March 12th and had 20 attendees (who came & went at different times) – including a guest presenter. Society president Osvaldo began discussion by informing the group that USC has requested a launch of their 6″ booster rocket in April, before leaving the meeting to go on a Home Depot supply run.

Screenshot of discussion during the monthly meeting

GUEST PRESENTATION – GEORGIA TECH YELLOW JACKET SPACE PROGRAM

Sam Kim from the Georgia Tech Yellow Jacket Space Program made a presentation on their mission to be the first collegiate team to send a liquid rocket to Karman Line. The team conducted the first hot fire of an 800 pound-force LOX-kerosene engine in November 2019 (pictured below). This engine will support a sub-scale rocket which will be used to prove and test methods on this student-designed, -machined, and -assembled project.

November 2019 static fire of the Georgia Tech YJ-1S rocket

The team has planned a launch for the sub-scale rocket in October to an apogee of 5,000 ft. An 11-second burn static fire of this engine is expected in April. The team conducts testing out of the DeKalb-Peachtree Airport, and plans to make launches from the Spaceport Camden in southeast Georgia.

BILL CLAYBAUGH’S 6″ ROCKET

Bill Claybaugh presented a number of hardware pieces related to a 6″ rocket which he hopes to launch this year. The rocket will fly on a 6″-diameter, 60″-long motor producing 1,350 lbf of thrust with an 8.3-second burn time. This design is optimized to be used as the second stage in a rocket boosted by a 9″-diameter motor, but the impending flight is only the 6″ second stage. Bill mentioned that he has a test flight planed for the 9″ first stage some time within the next year. The combined 2-stage rocket will have to fly out of a national range because of the expected altitude of 120 statute miles.

Bill showing off the avionics package on his rocket

The hardware that Bill C. presented from his rocket included the tapered fins, bulkhead assemblies, and a section of the 40″ avionics payload which will be mostly contained within the nosecone. In addition, Bill provided insight on the FAA paperwork that he is currently completing for the flight of the 6″ rocket. The FAA form 7711-2 he has been working on is the same one used for airshows, and requires a supplemental that covers both class 2 & 3 amateur rockets. The final hurdle is the “splash pattern” Monte Carlo analysis of over 1,000 launches with varying launch angles, wind, and other launch parameters to determine the probability of landing in a populated area. He expects the launch will be deemed safe, and plans to submit the paperwork soon.

PLANS FOR THE UPCOMING MTA EVENT – SAT. MAR 20

Several members stated their intentions to join the launch & work event at the MTA site next Saturday, March 20th. Work on welding the new plate on the vertical test stand, clearing brush in the launch/firing areas, and other site maintenance may take place if time and equipment availability allow. There has also been discussion of taking an inventory of the working order of some Society equipment (such as the PA system) stored at the site.

Bill Inman plans to once again bring out his solar-powered steam rocket, Solar Cat, which uses mirrors to heat water with sunlight. Bill has been a fixture at MTA events the past several months, perfecting the design and procedures so that he won’t be caught unable to launch because of a minor oversight like untested equipment or cables that are too short. Although all of his equipment is flight-ready, MTA launches are always at the mercy of the Mojave desert weather. Wind, rain, and sunlight permitting – we hope to see the Solar Cat take to the skies next weekend!

Early stages of Dimitri’s water bottle rocket module, which is now assembled & ready for testing

Wolfram Blume is vaccinated (an impediment to his attendance at last month’s event) and ready for another launch attempt of the booster stage on his rocket, Gas Guzzler. In the final version the upper stage will include a gas-powered ramjet, but this flight will be flown with water instead. The goal of this test is to measure drag & acceleration, particularly during separation of the booster stage, which will help inform the final design parameters. We’re excited to see this launch, and expect it will be a fun one to watch!

Keith Yoerg will bring his model rockets and multi-pad wire rail launcher to test out deployment boxes and high-power solid rockets to test LoRa GPS trackers as a cheap rocket tracker. Dimitri is finishing work on a his hybrid & water rocket launch controllers (pictured above), both of which should be ready for testing on Saturday as well. It was once again agreed that a grill-out should take place, which is quickly becoming an MTA event tradition.

WIRELESS LAUNCH CONTROLLERS

The last topic stimulated a great discussion on the use of wireless launch controllers, with many members providing thoughts and opinions. Richard Dierking presented the commercially available Wilson F/X wireless control box, which consists of the firing box shown in the photo below and 2 wireless modules which run on 12V gel cell batteries. This entire system cost him around $900, and larger versions of this system have been used by the Rocketry Organization of California (ROC) and Friends of Amateur Rocketry (FAR) for launches of high-power solid rockets.

Richard Dierking showing a Wilson F/X wireless control box

Dimitri expressed his comfort and trust in the Cobra wireless firing system, which he has used many times as the Pyro Op for million-dollar shots in movies and television. The Cobra system uses 64-bit encryption (it was suggested that the Wilson F/X system uses 32-bit) and the only issues Dimitri reported was when attempting to fire directly near an ultra high-speed camera. Richard stated that he would look into getting someone from the Wilson F/X company to attend a future RRS meeting to describe that system in further detail.

Most members expressed cautious optimism about the potential of using wireless launch controllers at RRS events, though it was re-iterated that the Pyro Op in charge has the final say in what firing systems may be used at any event. The consensus best path forward was progressing slowly by starting with LED lights & low energy firings like model rockets. The aim is to build experience with and knowledge of these systems to determine if they can be safely used for more energetic firings. Richard & Dimitri plan to bring the Cobra and Wilson F/X systems up to the MTA event next weekend, where (with the permission of the Pyro Op in charge) they will be tested safely on a small scale.

NEXT MONTHLY MEETING

The next RRS monthly meeting will be held virtually on Friday, April 9th at 7:30 pm pacific time. Current members will receive an invite via e-mail the week of the meeting. Non-members can request an invitation by sending an email to:

secretary@rrs.org

The Executive Council has committed to an additional monthly meeting moving forward to address administrative matters. Members who would like to discuss an admin topic in detail can request attendance at a Council meeting by sending an email to the Secretary at the address above.