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A 1/48 scale model of the SpaceX Falcon Heavy rocket

bps.space

51–60 of 96 posts

Re: A 1/48 scale model of the SpaceX Falcon Heavy rocket

#51
post #37

Earlier quoted context omitted.

I just watched a couple of his videos, and it sounds like he got pretty close to landing with solid propellant ('echo'), but ultimately decided that it was too finicky and ended that project to move onto a liquid biprop rocket.

Are liquid engines still in the realm of hobbyists? The estes engines he's using are pretty widely used and understood to be fairly safe, is there something equivalent for liquid rockets?

>> understood to be fairly safe, is there something equivalent for liquid rockets?

No. Lighter fluid can be a reasonable fuel, but the oxidizer is the issue. Either you use liquid oxygen (very cold, explosive, generally dangerous) or something nasty like nitric acid or MMH that will eat your flesh for lunch.

Given the altitudes involved, I would suggest that small jet/turbine engines meant for model aircraft would be more useful. They wouldn't need oxidizer.

Re: A 1/48 scale model of the SpaceX Falcon Heavy rocket

#52
post #45
post #28

Gimballed thrust puts this squarely into all the cool hobbies involve ITAR territory.

The tube launched rocket looked decidedly weapon-like too. Cool tech though. Hope he doesn't get into trouble

He’s been pretty careful to not do anything illegal (he’s talked about this in a few live-streams), for example not open-sourcing any of his control software and using just local IMU data for in-flight control.

Re: A 1/48 scale model of the SpaceX Falcon Heavy rocket

#54
post #32

Earlier quoted context omitted.

Majority of engineers with a degree are useless right after graduation. Its a ton of random math that (most) of which you don't use again since you use modeling software. Source: Did Aero Someone doing this as a Amateur can damn well pick up whatever they need to.

Even at space X level of innovation ? I was under that impression that maths could still be useful when working at the very bleeding edge of an engineering field.

Bear in mind that companies at the scale of Space X doing safety critical work tend to parcel up tasks fairly minutely. Everything is compartmentalised, tested separately and there are whole teams devoted to the large scale architecture and integration. There's a joke that back in the space race days, an engineer might be responsible for a single screw on the Saturn V (and you'd be damn sure if the thing blew up, it wasn't your screw that did it). Same thing happens with ESA and NASA contractors.

There are lots of engineers who are basically building things to a spec and aren't what you might call innovating.

I think someone who builds rockets to this level would be absolutely fine in an entry position. They just might need to get some of the theory first. Saying that, he clearly understands mechanical design and control theory.

Didn't one of the chief engineers at SpaceX start out with model rockets?

Re: A 1/48 scale model of the SpaceX Falcon Heavy rocket

#55

Earlier quoted context omitted.

Rare gem - the bulk is made of open source stuff no one asked for, rants against employers, and weird calls to revolution. Worth staying for the rare ones tho.

Those open source tools are sometimes how I stay employed. Wouldn't want to be without HN.

True - but I am referring to useless open source posts. Forgot to add those claiming OOP, code documentation, and so on, are useless. Waste of time and are a distraction from what you mentioned.

Re: A 1/48 scale model of the SpaceX Falcon Heavy rocket

#56

SpaceX has a huge potential opportunity for raising funding / earning profits via toy licensing and sales: https://www.barrons.com/articles/spacex-overwhelmed-by-deman... Wouldn't it be interesting if Elon could achieve his Mars objectives faster not by selling LEO satellite services or space launch capacity but by selling and/or licensing toys (and sparking dreams) here on Earth? Despite the current pandemic, this i…

I know this is a tactic Elon has definitely used before - i.e. hats and flamethrowers to fund the Boring company.

I can't find the source because Google is a bit biased towards giving me articles about yesterday's launch but I know at a press conference w/ NASA Elon stated the technology they're developing for NASA should not be considered proprietary and that NASA could do what they wanted with it. With that being said, the Falcon 9 designs have to be SpaceX's IP.

Re: A 1/48 scale model of the SpaceX Falcon Heavy rocket

#57

Earlier quoted context omitted.

What he's done is super impressive and cool, but has he acquired the necessary base knowledge to work on an avionics, propulsion, etc team at SpaceX? I'm not in any of those fields, but I'd have to imagine there's a large amount of background knowledge that someone with an aero or mechanical engineering degree has, that he hasn't picked up with model rockets.

Majority of engineers with a degree are useless right after graduation. Its a ton of random math that (most) of which you don't use again since you use modeling software. Source: Did Aero Someone doing this as a Amateur can damn well pick up whatever they need to.

Might be true, but SpaceX is only hiring mechanical/aerospace engineering degree holders for the relevant positions: https://boards.greenhouse.io/spacex/jobs/4740817002?gh_jid=4...

> BASIC QUALIFICATIONS:

> Bachelor’s degree in mechanical or aerospace engineering

> 1+ years of experience designing and analyzing mechanical systems via professional work experience, project/research-based student experience, or a combination of both

which OP doesn't have. They're not just hiring randos who can do math, they're looking for people with specific backgrounds in this domain.

There are of course other jobs, like PR, graphic designers, accounting, HR, benefits, facilities, that require zero engineering background, that all big companies must have to just keep the lights on.

Re: A 1/48 scale model of the SpaceX Falcon Heavy rocket

#59

Earlier quoted context omitted.

From his about page: "I studied music production in college, and after seeing the ambition of SpaceX, and the excitement in the new space industry, I was hooked. I wanted to work in aerospace... " At first, I wondered what SpaceX role would suit him best and why SpaceX hadn't hired him. Then it occurred to me that humanity might be better off with passionate polymaths such as him working outside as opposed to inside…

What he's done is super impressive and cool, but has he acquired the necessary base knowledge to work on an avionics, propulsion, etc team at SpaceX? I'm not in any of those fields, but I'd have to imagine there's a large amount of background knowledge that someone with an aero or mechanical engineering degree has, that he hasn't picked up with model rockets.

He buys the rocket motors. From his FAQ:

> Do you make your own motors?

> Nope, I use commercially available propellants. Usually black powder motors from Estes or APCP motors from Aerotech. For custom or more complicated builds, BPS.space outsources propellant work to other manufacturers, who can often achieve higher precision and predictability than any consumer setup. I learn best by experimentation, which works very well for software and electronics, less so for explosives and propellants.

> I also got a C+ in chemistry during high school - designing and making rocket propellant is not a good idea for me :)

It sounds like he makes the rocket housings then tweaks some parameters to make them fly.

Re: A 1/48 scale model of the SpaceX Falcon Heavy rocket

#60
post #45

Earlier quoted context omitted.

The tube launched rocket looked decidedly weapon-like too. Cool tech though. Hope he doesn't get into trouble

He’s been pretty careful to not do anything illegal (he’s talked about this in a few live-streams), for example not open-sourcing any of his control software and using just local IMU data for in-flight control.

Is this a typically US thing or does this kind of thing risk getting you into trouble elsewhere too? I mean the first thing you'd want to try once you have a "platform" is things like GPS guidance, adding wings & making cruising rockets, trying terrain guidance etc. Isn't the cat out of the bag with this kind of tech already, much like strong crypto was once a non-exportaple technology in the US, but now it isn't? What exactly is the tech that is off limits (I don't mean tech that will get someone to come to your house and ask questions, but tech that is actually 100 % certainly illegal?)
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