Interstellar Technologies Inc. who are working towards a guided suborbital rocket flight (Momo) and eventually a small satellite launcher, have recently been making progress with their control system experimentations.
LEAP or Flight test for attitude control is a vertical take off lunar landing looking rocket that has been designed to test the team’s control system. Four flights have been carried out so far, and as can be seen in the video’s below, steady progress has been made.
Although not new video’s, I thought it was worth posting as it is interesting to watch and see the teams progression to date.
The team were due to hot fire test their Galactic Aztec Heavy rocket but ran into a few minor issues that forced a scrub.
Galactic Aztec Heavy is powered by an LR-101 rocket engine, is 25ft in height and 650lbs in weight and is expected to reach 50,000ft with a top speed of Mach 1.3.
Video Cation: Video from the 2nd test run out of four on February 4, 2017. This is the same BPM-5 engine being tested, which is also going to be flying with the Nexø II rocket, launching early this summer. For more information visit: www.copsub.com
Look like we will see another hot fire of the Galactic Aztec Heavy on Feb 4th. The last hot fire conducted by the team saw the LR101 engine run rich as it had a burn through at the throat. The team have since been able to obtain more surplus engines to enable the rocket to see flight!
An update on Roberts rocket project as he works towards the flight of his 250lbf liquid fuelled rocket. Robert has been working towards a full up static test of the rocket, with thoughts on how to use his existing infrastructure to conduct this.
The existing test stand structure will be reused but extra components have been added to secure the rocket vertically. Two 8-foot 3030-S beam extrusions from 80/20 Inc. will be attached to the test stand and supported by aluminum angles. The 80/20 beams are more than I need for this application but I plan to use them later during final assembly to help with alignment of the skin to the frame. The rocket will be mounted 6 inches away from the beam using 3 x 6 x 1/4 inch square tubes as spacers. The thrust load will be reacted through two 1 x 1 x 1/8 inch angles that tie into the injector manifold at the top of the engine and then to the vertical beam.
Robert also talks about modifying a CDI ignition system to provide feedback before opening the igniter valves, this guarantees 100% the sparkplug of the igniter will be working when the propellant is passed through it, thus allowing the main engine to be ignited.
One feature I wanted onboard was feedback from the CDI ignition module to verify it is working before opening the igniter valves. However, the CDI power supply comes from an isolated offboard source so I had to design an optoisolated current monitor circuit that ties into the onboard data system
I have just personally ordered a CDI ignition system for my own project so it will be interesting to see how this works out.
For the last few years I have been developing my 1000lbf (4448N) LOX/Ethanol rocket and engine, this rocket is based on the construction of rockets as by the SDSU Rocket Project. Consisting of aluminum bulkheads with square box stringers, I saw this design as a good starting point as it enables easy placement of components within the airframe when I am not entirely sure how it will work. Being my first liquid-fueled rocket, it gives me room to move and improve.
As of late though I have been thinking about the future, given the cost and my workshop capability, a smaller diameter rocket could be worth pursuing. Going smaller also means trying to fit all those valves and plumbing into a set diameter airframe.
Lucky for us, Tom Mueller, VP of propulsion at SpaceX has wrote a small article about pyro actuated valves that he has built in the past for his own experimental rocket projects. An example from the article is shown below.
These valves enable the builder to employ them in a smaller diameter airframe and in one case, were used in an airframe of only 1.5″ diameter for a liquid fueled rocket. The downside is that they can only be activated once and therefore you require a rocket/system that you know will work every time you hit fire. The plus side is that you can use them everywhere, from your main propellant valves to vent valves to your helium actuation valve as the document states and outlines.
Paul Breed of Unreasonable Rocket has also explored these valves, there is a nice blog post detailing his approach to the concept.
Although this is nothing new to the world of rocketry is does offer food for thought when going through the design phase and enables another option to be looked into when trying to downsize and save money.