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Comment by Aurornis | Hacker News Reader

Awesome project, but are there any actual videos of it running the jet engine?

He says the jet engine moves 11,000 CFM of air, but that air can only come through the windows and the sunroof. Pulling 183 cubic feet of air per second through those little openings while sitting in the drivers seat isn't going to work. Just try to do the math on how fast that air would have to be moving through those windows.

Cool show piece though.

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This not a typical low-bypass, cigar-type turbofan jet engine you see on airplanes, rather, it’s a modified turboshaft jet engine used for helicopters, intended to provide longitudinal rotational energy. The air it moves from the intake is a fraction of what it produces as the combustion process itself results in gasses being chemically formed. There is no propeller or fan on this engine - it’s closer to a rocket than what we think of as a jet.

> it’s a modified turboshaft jet engine used for helicopters, intended to provide longitudinal rotational energy. The air it moves from the intake is a fraction of what it produces as the combustion process itself results in gasses being chemically formed.

It's not a turbofan no but it's a jet engine burning fuel the regular way (using air), like the ones on a B-52 or Concorde. Very different from a rocket engine that carries its own oxidiser.

I’m fully aware of the difference. The only parallel I’ve drawn is the fact that it uses gases as a result of the combustion as propulsion rather than spinning a fan. Whether it has its own oxidizer is irrelevant for the purposes of this analogy as I don’t see this vehicle achieving any sort of space flight.

Give 6 sq ft for openings, that's around 30 linear feet per second. ~30 feet per second is ~20 miles per hour. That's a stiff breeze, but it doesn't seem outrageous.

Yes, there's video online.

https://www.youtube.com/watch?v=TCqxWhKe_tA

https://www.youtube.com/watch?v=5zNdkXwFQ3c

(Noise warning, for obvious reasons.)

I see

> I don't know how fast the car will go and probably never will. The car was built to thrill me, not kill me. That doesn't stop me from the occasional blast on the highway though.

but I am unsure if that means he has never driven it using the jet engine, or whether the engine even will power the car or just kinda runs on its own. I'm curious to see it go at all under jet engine power.

Edit: maybe this is it https://www.youtube.com/watch?v=R-ipYAl3o40

I think he means he's used it plenty, but hasn't tried to max out the speed.

That's my reading as well.

I have a vague memory of this site or an interview previously saying he got up to 130 mph once, before deciding he'd rather not find out what speed a VW Beetle lifts off the pavement.

That videos's an original Beetle, not a New Beetle.

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