You can have an idea, but getting it into production, especially if the entire design hinges around it, is an entirely different story.
From the article, the new engine is to wide to fit a number of existing planes.
"But for more than 40 years, his abiding passion has been the idea of a small jet engine for light aircraft."
Williams[1] had that vision too. He'd produced the jet engines for the first cruise missiles, and many other successful jet engines. But he was never able to break the cost barrier.
Below 6 passenger bizjet size, jet engines don't seem to get much cheaper. Smaller engines can be made, but the price doesn't go down by much. NASA had a big push for smaller, cheaper jet engines in the 1990s. Failed.
Maybe with better manufacturing techniques, like making all the plumbing in one big 3D printed piece...
Kind of a strange exercise they are doing. Not that I can blame them, I'd be pulling it apart to see what makes it tick myself.
As a practical exercise, however, this is rather futile; they aren't going to be able to replicate the stealth technology, nor the electronics, nor the engine...or anything else important, for that matter.
What they do have, however, is a large scale model making hobby. Maybe they should contact Airfix or Revell for a licensing deal.
Yeah as I was reading this, all I could think about was how there was no serviceability or reproducibility, the focus was on just building it, probably within a weight budget. There doesn't seem to be any long term breakthroughs or industry advancement here as all applications are specific to this model. By sealing the wings forever you are sort of guaranteeing steady business for the fabricator's check book as new ones will have to continue to be built for whenever there's damage (ground strike, etc).
At my dad's work (Rocketdyne-owned by Pratt&Whitney, used to be owned by Boeing, makes engines for space craft), they have several large rapid prototypers that are used to create prototypes for different designs to test, and they even make an air duct used in F/A 18s.
They're really fun, but what they can create is rather limited from my understanding. They can do very intricate designs (even objects within objects, like a triangle INSIDE of a complete sphere), but only out of certain plastics, and only one material at a time, so the usefulness is limited. You couldn't build an engine block with it, because it can't work with the metals.
I thought by now there'd be kits like plastic airplane models. Injection-mold a bunch of parts, connected by sprues, and throw in the odd bits of (metal) hardware where they are critical to the whole.
Safran's M88 should be sufficient for Boom's 1/3rd scale demonstrator I think? Then at least they'd have something to show other manufacturers and investors.
And you did, at least, go through full ISO 9100 certification, as the minimum to make the long list of suppliers for flying parts.
It is becoming so frustrating to read all those tech bro comments, believing that doing some messy 3D printing is the same thing as manufacturing. Ignoring that the whole field of mechanical engineering exists.
Thinking like that, a bunch of millions, get you the Titan and five dead people. Add some billions and it gets you FSD and a bunch of dead people.
Oh, and accounting and cost calculation seems to be a black art as well...
Do these designs scale up? Don’t see why we haven’t created full sized aircraft with this form factor. Seems like it would make a great aerial weapons platform.
Don't a lot of aerospace engineers today also design and build their own model airplanes? Sure, they aren't building 787s in their backyard, but neither am I building an SAP competitor in my bedroom.
This time, I don't see this being much better. My early childhood aspiration was aeronautics. I believe as somebody who built a semiflyable motoglider as a 15 years old in 2006, I can comment on technical soundness of this. Biggest red flag in the design are fans in front of the wing. Turbulence from them will be randomly stalling the wing, and most likely asymmetrically - which leads to a corkscrewing risk, especially with that huge elevator.
The classic of this is the Lockheed Skunkworks. It's success has never been repeated - lots of companies try to create a skunkworks clone, but try to fix it, and wind up thereby breaking it.
Any idea how often the final design and the prototype don't match in terms of volume and aerodynamics? I would have assumed that those parts are the easiest to model with high confidence.
My dad was in purchasing for various aircraft manufacturers, including McDonnell Douglas and Boeing.
It was literally his job to try and keep this nonsense under control.
It was extremely frequent that the engineers would request some screw with hyper specific requirements and would end up costing dozens of dollars or so per screw. Even more for the specialized tooling that would go with it.
From his perspective, the engineers loved designing new things rather than looking up, if anything previously existed.
So he would try and take the requirements and see if there was some off-the-shelf substitution that would meet the requirements. Saved companies a fortune again and again.
The real pie in the sky stuff is figuring out open designs that are durable but not so complex as to be totally out of reach.
I cannot claim to know the relative difficulty of such a task, or relevant regulations. But if there were some standard designs that multiple manufacturers were involved in, I bet parts would stay in production for a very very long time.
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