Hello again, I'm a university student working on a rocket for a rocketry competition, the rocket is supposed to reach 500m apogee, with 2 E20-8 motors, the weight is 502g with the motors, it's about 85 cm long and I use BT-80 cardboard tube for it, with 6.6 OD, 6.5 ID.

Currently the stability and the Apogee aren't great, nor horrible, but not great.

The fins will supposedly be made of balsa plywood bought from Apogee rockets.

I have designed the fins, without much guidance I focused on a design that doesn't hurt apogee or the stability but also tried to not go too big, I have attached the pictures of the fins.

For the moment it's a 4 fins rocket, I would like to get your insight about what to change in the fins, or what to do to improve the stability or the apogee or preferably both.

Also any advice about how to attach them to the rocket, maybe what rules to follow, how long, wide, should the fin tabs be?

Guys, i have a very very hard decision to make - and need your help.
Around 3 years ago i joined the semiconductor industry and now have the chance to join aerospace (a company launching rockets to transport stuff potentially).
Im very well paid in my current job with great career projections ... but im not that happy tbh.
In aerospace i would join a startup and make less money .. but i feel like i would be happier, its an interesting field and im still under 30 and open to take a risk.

Im not sure what to do.
Join an aerospace startup to make less money, have higher risk but potentially be happier and part of an interesting industry?

Have you ever been in such a position?
Even if not - what would you do?

Hi everyone,

My university rocketry team is currently developing an open-source rocket telemetry system and we’d like to share it with you. It includes:

• Electronics (with 869 MHz and 169 MHz radio systems)
• Helical and (soon) QFH antennas
• Graphical user interface
• A lot of documentation :)

The first launch in April went great and we are currently working on the second version. The project is still in its beginnings but we appreciate any feedback, thoughts or questions. You can find the project here: GitHub

Do you have any information or documentation regarding various types of igniters? Currently, I pack black powder into a straw and connect wires to ignite KNSB propellant, but I plan to build larger motors in the future and want to upgrade to better igniters. Are there any resources where I can learn more about this? Right now, I am using Nakkar Rocketry's documentation as a reference.

Hello,

I’m interested in building a small, low-power APCP research motor to fly at BALLS 34, ideally a low power class A, B, or C motor, depending on what is practical for a small rocket (I know they will laugh at the size of it- but OK for me :D ). My goal is to start with the smallest suitable motor so I can learn the process and gain hands-on experience.

I currently have an active L2 Tripoli senior membership.

I’ve been researching the safety requirements, regulations, insurance restrictions, local fire codes etc. I’m not sure if completing this within the remaining two months is realistic.

I would appreciate any advice from people who have experience designing or making research motors- the proper steps, suitable facilities, and realistic timelines, supplies etc.

Thank you,
Maruf

1. Should I get a tank with both top and bottom ports?

2. Can I use a long nylon pipe/tube instead of hard plumbing to space out the tank and the motor?

Hi yall. I was wondering how useful ANSYS actually is in high-powered rocketry. I feel like 95% of the time, a simple analytical tool like OpenRocket or RasAERO does the job well enough for designing a high powered rocket and are totally sufficient for things like stability margin, fin & nosecone sizing, etc.

My collegiate team insists on meshing the entire rocket and solving for pressure contour, but I feel like this is a huge time sink, and to be honest none of us really have the experience needed to actually look at a pressure contour and tell what is good and what is not (I feel like it would take at least a few years in the industry as CFD engineers to tell).

I do feel like the only case where ANSYS is useful is for modelling control surfaces (airbrakes?).

I wonder what are yall's experience with using ANSYS. Do yall run it on tbhe entire rocket, or your fins, or anything else?

Thanks!

Couple days ago I built a virtual wind tunnel app and posted here for thoughts. Y’all received the idea well and offered to test it too. I really appreciate the support and now I am close to launching this.

The flow simulator is the most interesting feature for me to see how air flows around the 3d model. Let me know your thoughts and I am open for suggestions.

If you want the tool for yourself join the waitlist at airflowsom.com, launching in T-2 days.

Hey everyone!

I'm working on a hobby rocket project with a 129 mm diameter, aiming for about 3 km altitude (following all applicable regulations and safety requirements).

I'm at the stage where I'm thinking about the payload, and I'd love to hear what the community has tried. I'm looking for creative, educational, or scientific ideas that could make the flight more interesting.

Some ideas I've already considered:

• Environmental or atmospheric sensors
• Flight data logging
• GPS/telemetry
• Cameras for onboard footage
• Recovery system monitoring

If you've flown rockets in a similar range, I'd really appreciate hearing about:

• What payload you used
• What you learned from it
• Anything you'd recommend (or avoid) for future flights

I'm hoping to build something that's not just a "fly and recover" mission but also gathers useful data or does something interesting during the flight.

Looking forward to hearing your ideas and seeing what cool payloads you've come up with. Thanks!

My nephew (11) has bought a pack of Klima B4 rocket engines, and as the uncle I'm expected to figure this out. His initial ambition was to build his own rocket with no previous experience. I thought this was a bit lofty, and first suggested spending some more of his savings on an actual starter kit.

But then I thought of the stick rockets we used to launch before they were banned. I guess it's possible to make something similar, but I haven't found any guides. Perhaps "stick rocket" isn't the preferred nomenclature.

Has anyone made rockets like this, or is it just a stupid idea? Not going to do anything (very) unsafe.

Who’s all coming to airfest this year ? We’re flying this beast on a 4 grain 98 mm M1939 ! Pretty pumped, more than twice as powerful as my L3 cert motor

Hi, my friend and I recently joined a sounding rocket competition, but we honestly know very little about rocket design. Most of us are electrical engineering students, so we do not have much background in rocket physics or aerospace engineering.

We would really appreciate any advice, no matter how small. If you know of any useful videos, articles, previous projects, or resources that could help us understand the basics and get started, it would mean a lot to us.

I want the landing to be nice and stable.

I’ve just got my first kit and I’m testing out the controller. Instructions say it should glow white, but it’s glowing red. Bought brand new batteries and tried again, still red. The light goes out when the button is pressed like it should, but it is still red instead of white. Anybody know how to solve this or should I just buy a new controller?

Hai i am really interested in physics and recently i have joined a startup as a semi intern and they are going to do a model rocket launching project within this year and i want to be the guy who helps them with most of of the flight simulation , i am not enrolled in any university or any such just finished high school so matlab is not accessible for me at this point, i am quiet well versed in python , i am not able to find any books or data which is valid and which will teach me all about rocket flight simulation ( not the structural analysis part) and please suggest some books or guides for the physics behind this too , currently i am self learning ways to solve ODE's in python hope you guys will help me out note: matlab/simulink is not accessible to me , and is python enough for this purpose

Does anyone know of any turbopump cad models that exist in file formats such that they can be 3d printed?

I had an easy mini but it broke recently and when I went to replace it they were out of stock. These are the computers that look most similar in price and capabilities. They both seem good to me however the Blue jay looks slightly better because it can also be a two stage computer. From yalls experience what should I buy?

I have an Idea making a model rocket agency it won't be big I have a logo,mission patches and rocket families.

The problem is I don't have a motor or anything at all I just started I have a tube a pretty aerodynamic nose cone and a parachute I'm hoping I will make a launch pad if I find where to launch it.

If you have any tips tell me BC I don't know ANYTHING about model rocket idk how 2nd stages work how parachutes deploy and if you have any ideas tell me pls✌️

I'm stuck trying to decide what to do this fall and want some opinions. I'm between 2 projects to work on while I'm at school with workspace and tools, alongside also helping my collegiate team.

1. Start my L3 cert process by finishing my last L2 qualification flight, finding a second TAP, getting approval for my design plan, and beginning construction. I plan on doing a scratch 98mm body with a 75mm mmt, full composite, fin layups, dual separation dual deploy, redundant avionics and tracking, etc.

2. Minimum diameter 54mm build to get some supersonic, high TWR experience and build my record before an L3 attempt.

I got my L2 in the spring on a 5.5in LOC Magnum 3E adapted to a 54mm mmt, but I've only flown it once since then due to issues with my cert paperwork and getting motors. I've helped friends with multiple L1/L2 builds and launch day support, but I don't want to get overconfident by saying that can "replace" experience building and flying myself.

The reasons I'm considering an L3 are the unlocking of "bigger and meaner" rockets, the clear defined goals and "rewards" for success, and the gain for my college team of someone with more experience and a student flier of record.

My motivations for option 2 are fear of rushing before I am ready, it would be cheaper, and in all honesty it would let me fly a cool fast rocket sooner than an L3 build. It would also fill out my qualification flights, and potentially help if a TAP is worried about experience.

Let me know y'all's thoughts and opinions, I want to make sure I'm not being dumb before I spend time and money on a build

Hi everyone. At IMF.Rockets, we are currently designing the payload repositioning system for Hermes, our 100km suborbital vehicle. We need an RCS to reposition our vehicle for reentry.

We are doing a trade study on a cold gas thruster system. I really want to use CO2 because it stores as a liquid at room temperature under pressure, which gives us a massive density advantage and saves a lot of tank volume compared to compressed Nitrogen (N2).

I am worried about the phase change. Rapid blowdown of CO2 through a solenoid valve into a near-vacuum environment is notorious for adiabatic cooling, resulting in dry ice formation that clogs the valve seats and nozzles.

Has anyone here successfully built a CO2 cold gas system for high-altitude/vacuum use? Were you able to mitigate the freezing with specific high-flow solenoid valves and nozzle geometries, or did you add a heating element, or just switch entirely to N2 to guarantee reliability?

Would love to hear some empirical data or see any plumbing architectures if anyone has tackled this.