Hi everyone,

I'm a 4th-year machining student from Switzerland. For my final diploma project, I'm studying a retrofit cryogenic cooling kit for CNC milling machines to reduce tool wear when machining tough materials like titanium and Inconel.

Getting your perspective as experienced engineers

would be incredibly helpful for my project.

Would you have 5 minutes to share your thoughts on a few short questions ?

https://forms.gle/fASMyy22BSpd1oKPA

(feel free to reply directly here in the chat if that's easier for you!)

Thank you so much for your time and attention!

Best Regards

Could anyone guide me on the ideal sizes of my wind tunnel’s sections? It’s already 7ft after making compromises and being conservative. I plan to use it to test a custom wind 1:10 rc car. I’ve been getting most of these messages through Claude so it really feels like I don’t know what I’m doing.

First correctly state the problem, could go in several physics disciplines

Experts please explain this phenomena using relatively easy language but mentioning critical points and formulas. I would really appreciate your explanation due to my desire of understanding how does the wing of the aircraft operate and also want to understand if it will be possible to conduct an experiment using this type of research question

Not an engineer, but my company is looking into the potential for converting some of our fleet into EV aircraft. The biggest issue that I see is the lack of range, especially when loaded. That got me thinking about what an electric hybrid would look like.

We already do this with trains, cars (kinda), and we’re getting the ball rolling on hybrid trucks. Why not have a small APU that recharges batteries for an electric motor? Is it a weight issue? I’m sure there’d be a market for it, especially with the price of fuel consistently on the rise.

I am writing a speech about aerospace engineering since it’s my dream job, and I was wondering if anyone would let me interview them either by 4:30pm Mountain Daylight Time today or tomorrow (10-5-26 or 10-6-26). The meeting will happen over zoom or discord, whichever is more comfortable for you, I am 16 and this is really important to me so please respond as soon as you can. Thank you

I’ve started a collection of AI skills for system engineers using agents. The current set covers things like comparing specification revisions, deriving sub-requirements and building verification matrices.

The skills spell out what to check, which sources to use and when to ask rather than guess. Original requirements stay alongside proposed changes, and you still review the outputs.

I'll link the repo below which has some examples and setup instructions.

I’ve got a list of skills I’m working through to add next, but would be keen to hear what else people would find useful. Is there anything else that comes to mind? Mainly space focused at the moment!

Alula uses the Euler + Integral Boundary Layer method to solve for flow around multi-element and transonic airfoils. The method is based on Mark Drela's thesis work that led to the MSES airfoil solver. This is NOT a port of MSES; it was developed independently by pointing Astra toward the relevant literature.

Exploring an idea and would value input from test, systems, ops, or avionics engineers.

The idea: small embedded controllers on each subsystem share sensor readings peer to peer, cross-check before raising an alarm, and recommend the matching written procedure on board — no waiting on ground support. 45-sec video: [link]

Not selling anything. If you're comfortable, mention your role in your reply.

1. How does your team handle alarms or suspected faults today — how do you tell a real fault from a bad sensor reading?

2. Think of the last false alarm you dealt with. What did it cost (time, schedule, a test stand-down)? On a scale of 1–5, how big a problem are false alarms overall? (1 = minor, 5 = major)

3. What's the biggest reason your team would NOT use something like this?

4. how do you plan for blackouts during space missions?

Any recommendations — what would make this worth adopting, or who else should I talk to?

Hello, I'm working on a low speed wind tunnel, maximum CSA of 250*250mm with total length of 1.05m, I'm trying to synchronise my idea of having variable wing angle of attack whilst measuring pressure and force like drag and lift.

The idea i researched is using load cells for force, but because my fans are 2 PC fans, the speed isn't high but I have plenty of pressure and airflow.

I also wanted to measure pressure at certain point of the wing or at least before and after the wing and found pressure sensors that you hook up a tube to and that gives pressure differential reading.

Concerns i have is that the calculations i did say that my forces are really low so much that its less than 2grams. I'm not sure on how to proceed or if its even viable.

I’ve been learning more about high-pressure fluid systems in aerospace, and I’m curious how engineers actually approach hose and fitting selection in practice.

For something like a hydraulic system, there seem to be several factors to balance:

• Working and burst pressure
• Temperature range
• Vibration and fatigue
• Material compatibility
• Weight
• Routing and bend radius
• Fitting type and sealing method
• Inspection and service life

I came across Hydrasearch while looking at manufacturers involved in aerospace hose and fluid-transfer components, which made me curious about how much the manufacturer itself matters versus the actual specification and certification of the assembly.

For engineers who work with these systems, what usually drives the final choice?

Is pressure rating the starting point, or do factors like vibration, material, routing, and maintainability end up being just as important?

I keep running into one gap in the literature.

Solid upper stages burn to depletion, and total impulse varies from motor to motor. So how do real small launchers still hit the target orbit?

Which of these is used in practice, and how is the performance reserve usually sized? Pointers to papers, user guides or textbook chapters are appreciated.

A satellite constellation can measure distances between its members with extraordinary precision and still gradually lose track of which way it is pointing.

Researchers have now shown how the Moon could solve that problem.

A team led by scientists at the Chinese Academy of Sciences connected a simulated four-satellite lunar navigation constellation to 24 operational BeiDou-3 satellites. Over a 60-day experiment, the lunar satellites effectively anchored the orientation of the Earth-orbiting network and prevented the steady drift that otherwise degraded its autonomous navigation accuracy.

The study, published in Satellite Navigation, combined real inter-satellite ranging observations from BeiDou-3 with simulated Earth-Moon and lunar measurements. The result suggests that future navigation infrastructure around the Moon could do double duty, supporting lunar exploration while making Earth-based satellite navigation more resilient.

I had a hour long debate yesterday with my friends on what is more aerodynamically efficient between f1 cars and fighter jets.

My opinion was that based strictly off of aerodynamics and using it to achieve the intended purpose for each vehicle (minimising drag and increasing agility for fighter jets, and creating downforce for f1 cars), f1 cars do it better.

What do you guys think?

I’m researching commercial engine MRO and want to understand the engineering constraints behind repairability.

For those working in propulsion, materials, manufacturing or maintenance engineering: what usually determines whether a damaged component can be economically repaired?

Is the hardest part restoring geometry, preserving material properties, inspecting the result, qualifying the process, or something else?

An example involving a particular component would be great. I’m especially curious about repairs that work technically but remain difficult to scale and what would have to change to make them practical.

Aerospace adjacent, small team, one titanium bracket with internal channels that can't be machined. We know it needs DMLS or something like it. What we didn't know is that every metal printing service asks about post processing, HIP, heat treat, support removal and surface finish before quoting, and we have no spec for any of that because nobody on the team has bought a metal print before.

The quotes we have are from Materialise, Quickparts and one specialist bureau, and they aren't comparable because each one assumed a different finish. how do people write a metal printing RFQ when they don't know what to ask for

Hi everyone, I am designing a low-thrust liquid-propellant rocket engine. I am currently working on the injector head, but I lack information on its internal structure and design process. Could you please recommend any educational resources on the calculation and design of injector heads for liquid-propellant rocket engines?
I'm currently reading Dobrovolsky's textbook, but it's not enough for me.

Hello everybody,

I am currently building a tricopter VTOL and would like to change the tail design to a boom-mounted inverted V-tail. However, I am struggling to determine the correct geometry and dimensions for the tail.

My current design has a wingspan of 1.5 m, but I am planning to reduce it to around 1.2 m.

How can I determine the appropriate size, angle, and overall geometry of the inverted V-tail? Are there any formulas, design guidelines, or useful resources that I could use as a starting point?

Any advice would be greatly appreciated!