Solid rockets are a fun way to get started in rocketry. Brewing up a batch of rocket candy is something achievable even in the home lab, and anyone can give it a go with the right materials. Building a flight-capable liquid-fuelled rocket engine is another thing entirely, but the Purdue Space Program is up to the task.
The result of their hard work is Boomie Zoomie, a rocket which stands 15ft tall and weighs 130lbs. With peak thrust of 800 lbs, it’s got plenty of grunt to help get things off the ground. It’s fuelled by liquid methane, a first for a university-built rocket. The craft is constructed out of 6″ aluminium pipe sections, which were a best-case trade-off between weight, cost, and machinability. Special care was taken during the design process to make things modular, to both allow for future design revisions and ease of field prep. This allows different parts of the team to work independently, streamlining the process of preparing the rocket for launch.
Aiming to compete in the FAR MARS liquid rocket competition, the rocket has undergone two successful hotfires. The team estimates that the first launch should happen in the next few months. Preparations are continuing on the launch trailer and ancilliary support equipment to get things up and running. The aim is to reach a lofty altitude of 45,000 feet.
Putting payloads into model rockets can be more complex than simply shoving stuff into an open spot, so [concretedog] put some work into making a modular payload tube for his current rocket. The nose cone for his rocket is quite large, so he opted to give it a secure payload area that doesn’t compromise or interfere with any of the structural or operational bits such as the parachute.
The payload container is a hollow tube with a 3D printed threaded adaptor attached to one end. Payload goes into the tube, and the tube inserts into a hole in the bulkhead, screwing down securely. The result is an easy way to send up something like a GPS tracker, possibly with a LoRa module attached to it. That combination is a popular one with high-altitude balloons, which, like rockets, also require people to retrieve them after not-entirely-predictable landings. LoRa wireless communications have very long range, but that doesn’t help if there’s an obstruction like a hill between you and the transmitter. In those cases, a simple LoRa repeater attached to a kite, long pole, or drone can save the day.
We’ve seen [concretedog]’s work before, when he designed stackable PCBs intended to easily fit inside model rocket bodies, allowing for easy integration of microcontroller-driven functions like delayed ignitions or altimeter triggers. Better development tools, hardware, and 3D printing has really helped make smarter rocketry more accessible to hobbyists.
As the prospects for Germany during the Second World War began to look increasingly grim, the Nazi war machine largely pinned their hopes on a number of high-tech “superweapons” they had in development. Ranging from upgraded versions of their already devastatingly effective U-Boats to tanks large enough to rival small ships, the projects ran the gamut from practical to fanciful. After the fall of Berlin there was a mad scramble by the Allied forces to get into what was left of Germany’s secretive development facilities, with each country hoping to recover as much of this revolutionary technology for themselves as possible.
One of the most coveted prizes was the Aggregat 4 (A4) rocket. Better known to the Allies as the V-2, it was the world’s first liquid fueled guided ballistic missile and the first man-made object to reach space. Most of this technology, and a large number of the engineers who designed it, ended up in the hands of the United States as part of Operation Paperclip. This influx of practical rocketry experience helped kick start the US space program, and its influence could be seen all the way up to the Apollo program. The Soviet Union also captured V-2 hardware and production facilities, which subsequently influenced the design of their early rocket designs as well. In many ways, the V-2 rocket was the spark that started the Space Race between the two countries.
With the United States and Soviet Union taking the majority of V-2 hardware and personnel, little was left for the British. Accordingly their program, known as Operation Backfire, ended up being much smaller in scope. Rather than trying to bring V-2 hardware back to Britain, they decided to learn as much as they could about it in Germany from the men who used it in combat. This study of the rocket and the soldiers who operated it remains the most detailed account of how the weapon functioned, and provides a fascinating look at the incredible effort Germany was willing to expend for just one of their “superweapons”.
In addition to a five volume written report on the V-2 rocket, the British Army Kinematograph Service produced “The German A.4 Rocket”, a 40 minute film which shows how a V-2 was assembled, transported, and ultimately launched. Though they are operating under the direction of the British government, the German soldiers appear in the film wearing their own uniforms, which gives the documentary a surreal feeling. It could easily be mistaken for actual wartime footage, but these rockets weren’t aimed at London. They were being fired to serve as a historical record of the birth of modern rocketry.
While the jury is still out on 3D printing for the consumer market, there’s little question that it’s becoming a major part of next generation manufacturing. While we often think of 3D printing as a way to create highly customized one-off objects, that’s a conclusion largely based on how we as individuals use the technology. When you’re building something as complex as a rocket engine, the true advantage of 3D printing is the ability to not only rapidly iterate your design, but to produce objects with internal geometries that would be difficult if not impossible to create with traditional tooling.
So it’s no wonder that key “New Space” players like SpaceX and Blue Origin make use of 3D printed components in their vehicles. Even NASA has been dipping their proverbial toe in the additive manufacturing waters, testing printed parts for the Space Launch System’s RS-25 engine. It would be safe to say that from this point forward, most of our exploits off of the planet’s surface will involve additive manufacturing in some capacity.
But one of the latest players to enter the commercial spaceflight industry, Relativity Space, thinks we can take the concept even farther. Not content to just 3D print rocket components, founders Tim Ellis and Jordan Noone believe the entire rocket can be printed. Minus electrical components and a few parts which operate in extremely high stress environments such as inside the pump turbines, Relativity Space claims up to 95% of their rocket could eventually be produced with additive manufacturing.
If you think 3D printing a rocket sounds implausible, you aren’t alone. It’s a bold claim, so far the aerospace industry has only managed to print relatively small rocket engines; so printing an entire vehicle would be an exceptionally large leap in capability. But with talent pulled from major aerospace players, a recently inked deal for a 20 year lease on a test site at NASA’s Stennis Space Center, and access to the world’s largest metal 3D printer, they’re certainly going all in on the idea. Let’s take a look at what they’ve got planned.
Ever since the Pan Am “Space Clipper” first slid into frame in 1968’s “2001: A Space Odyssey”, the world has been waiting for the day that privately funded spaceflight would become as routine as air travel. Unfortunately, it’s a dream that’s taken a bit longer to become reality than many would have hoped. The loss of Challenger and Columbia were heartbreaking reminders that travel amongst the stars is not for the faint of heart or the ill-equipped, and pushed commercial investment in space back by decades.
Although Pan Am has since folded, we now have a number of companies working hard towards making the dream of commercial spaceflight a reality. SpaceX and Rocket Lab have shown private companies developing and operating their own orbital class vehicles is a concept no longer limited to science fiction. Now that private industry has a foot in the door, more companies are coming forward with their own plans for putting their hardware into orbit. In many ways we’re seeing the dawn of a second Space Race.
If all goes according to plan, a new challenger should be entering the ring in the very near future. Scheduled to perform their first test launch before the end of the year, Virgin Orbit (a spin-off of the passenger carrying Virgin Galactic) promises to deliver small payloads to Earth orbit faster and cheaper than their competitors. But while most other commercial space companies are using fairly traditional booster rockets to do their heavy lifting, Virgin Orbit is opting for a the less common air launched approach. Before Virgin joins the ranks of commercial companies exploring the final frontier, lets take a look at their plan for getting into space and the advantages it offers compared to the competition.
Model rocketry hobbyists are familiar with the need to roll their own solutions when putting high-tech features into rockets, and a desire to include a microcontroller in a rocket while still keeping things flexible and modular is what led [concretedog] to design a system using 22 mm diameter stackable PCBs designed to easily fit inside rocket bodies. The system uses a couple of 2 mm threaded rods for robust mounting and provides an ATTiny85 microcontroller, power control, and an optional small prototyping area. Making self-contained modular sleds that fit easily into rocket bodies (or any tube with a roughly one-inch inner diameter) is much easier as a result.
The original goal was to ease the prototyping of microcontroller-driven functions like delayed ignition or altimeter triggers in small Estes rockets, but [concretedog] felt there were probably other uses for the boards as well and made the design files available on GitHub. (Thanks!)
We have seen stackable PCBs for rocketry before with the amazingly polished M3 Avionics project, but [concretedog]’s design is much more accessible to some hobbyist-level tinkering; especially since the ATTiny85 can be programmed using the Arduino IDE and the boards themselves are just an order from OSH Park away.
On January 21st, 2018 at 1:43 GMT, Rocket Lab’s Electron rocket lifted off from New Zealand’s Mahia Peninsula. Roughly eight minutes later ground control received confirmation that the vehicle entered into a good orbit, followed shortly by the successful deployment of the payload. On only their second attempt, Rocket Lab had become the latest private company to put a payload into orbit. An impressive accomplishment, but even more so when you realize that the Electron is like no other rocket that’s ever flown before.
Not that you could tell from the outside. If anything, the external appearance of the Electron might be called boring. Perhaps even derivative, if you’re feeling less generous. It has the same fin-less blunted cylinder shape of most modern rockets, a wholly sensible (if visually unexciting) design. The vehicle’s nine first stage engines would have been noteworthy 15 years ago, but today only serve to draw comparisons with SpaceX’s wildly successful Falcon 9.
But while the Electron’s outward appearance is about as unassuming as they come, under that jet-black outer skin is some of the most revolutionary rocket technology seen since the V-2 first proved practical liquid fueled rockets were possible. As impressive as its been watching SpaceX teach a rocket to fly backwards and land on its tail, their core technology is still largely the same as what took humanity to the Moon in the 1960’s.
Vehicles that fundimentally change the established rules of spaceflight are, as you might expect, fairly rare. They often have a tendency to go up in a ball of flames; figuratively if not always literally. Now that the Electron has reached space and delivered its first payload, there’s no longer a question if the technology is viable or not. But whether anyone but Rocket Lab will embrace all the changes introduced with Electron may end up getting decided by the free market.