121–130 of 146 posts
This should be retitled "Now I'm going to finish adding jet engines to my wife's scooter."
The scooter seems like it could be a poor idea due to asymmetric thrust, and I have to wonder if he just mocked it up in jest. It does look pretty awesome though.
Seems like a good time to ask this question that has been bugging me forever, since all the HN jet nerds will be drawn to this thread: Why hasn't anyone made a hybrid car that uses a gasoline-powered turbine generator to charge its batteries instead of a piston engine? I'd imagine that hooking up such an engine directly to the drivetrain like in a Prius would be difficult, but surely a small turbine with one hell of…
I've been wondering about this very same question a lot myself and accidentally stumbled across the answer just a few days ago: Efficiency of turbines smaller than grid scale is simply not anywhere close to what piston engines can do at e.g. car size. Even at naval scale, turbines only win in use cases where power density is more important than fuel efficiency. Helicopters are deep in the (specific) camp of power den…
Although many navies do operate combinations of diesels and gas turbines (CODAG etc.), in such cases the diesels need to be installed on special shock absorbing mountings, in some cases even with a diesel-electric drive to avoid coupling the vibrations of the engine to the hull via the propeller shaft.
Earlier quoted context omitted.
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 tha…
> 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 tha…
Earlier quoted context omitted.
As an Australian-American living in the US I can confirm that the Australian concept of law (aka Nanny State) would ensure that this modification is illegal by default. Think of the children.
I was shocked as a Brit American living in the US how nanny state Aust is. Even more than Britain. Certainly when it comes to cars and driving. The whole ‘anti hoon’ thing seems shocking to me with my now mostly American sensibilities. But I guess that’s why we both live here rather than blighty or down under.
In the area I grew up, it was expected that your first car would be a V8. Hooning was ingrained into the culture. Back then it was a single spinner, no ABS, no airbags, basically no safety features at all. So what would happen is someone would get their licence, grab as many mates as they could, drive as fast as they could, and wrap their car around a tree killing everyone. Every week there was a news story about a multiple fatality P plate accident caused by hooning.
A culture of dangerous driving and dangerous vehicles led to Australia’s anti-hoon laws. It’s not just “ooh silly nanny state laws for no reason”.
Earlier quoted context omitted.
20 years ago in Australia my car got canaried because I had LPG and a pod filter, which was illegal because you were only allowed 1 modification to the intake system. I am 100% confident that if I strapped a jet to the car, it would be illegal. As it should be. If you want to do extremely dangerous modifications, do it on your own property. Not a public road where you risk killing a family of 5.
You're speaking from an Australian perspective about what is , to make an otherwise unsupported argument about what should be in the US. I'll be one of the first to point out problems and blindspots from the American conception of "freedom", but in this case it seems highly appropriate. You yourself even got bit by overregulation for something seemingly reasonable and forward-looking, and yet you're still reflexively…
What if a non-engineer who doesn’t understand the dangers makes this type of modification? This is is why it needs to be illegal. Just because someone straps a jet engine to their car it doesn’t mean they know what they’re doing, and _that_ is the risk, and why pretty much all laws exist in the first place. Many people could drive safely without speed limits, but we have speed limits to cater for people who can’t. My point is that if this type of modification truly is legal in America, that’s scary, and Australia got the laws right. A jet-powered car is not inherently safer in the US than Australia.
Seems like a good time to ask this question that has been bugging me forever, since all the HN jet nerds will be drawn to this thread: Why hasn't anyone made a hybrid car that uses a gasoline-powered turbine generator to charge its batteries instead of a piston engine? I'd imagine that hooking up such an engine directly to the drivetrain like in a Prius would be difficult, but surely a small turbine with one hell of…
A better option would be a constant speed ICE engine running at it's peak efficiency (like a diesel-electric train).
"The car has two engines: the production gasoline engine in the front driving the front wheels and the jet engine in the back." Careful wording to give the impression that the drive shaft of the helicopter turbine would be connected to the rear wheels, without actually claiming that it is. So it's a car with a large flame thrower in the back, minor The Boring Company vibes. Well possible that the author might have ha…
I don't think so. In another part he mentions > This is a helicopter turboshaft engine that was converted to a jet engine I can't see a way to get rotary power out of this engine after the modifications.
If you think there is anything done in this project to increase performance you are missing the point of the joke: woah, jet engine! Woah, rated 1350 horse power! Heh, retro novelty compact with a truly glorious amount of hot air.
Will the turbine exhaust noticeable push the car? Sure. Even a piston engine exhaust does, e.g. some versions of the Merlin engine claim extra 70 HP from exhaust thrust.
Is the author having great fun (and readers who get it) by brandishing the rated rotary power of the turbine over and over again, while carefully avoiding any mention of actual performance of the car? Absolutely. But it's not mean deception, it's friendly trolling. Which is basically the essence of the entire hot rod idea. I dislike the waste (of a good car, and the occasional kerosene burn, the turbine was probably beyond airworthyness certification and thus scrap anyway), but I find his "friendly trolling" charming in a surprisingly deep way.
Discussions on similar submissions: Jet Powered Volkswagen Beetle https://news.ycombinator.com/item?id=28349589 (August 29, 2021 — 2 points, 1 comments) Ron Patrick's Street-Legal Jet Powered Volkswagen Beetle (2006) https://news.ycombinator.com/item?id=16513835 (March 4, 2018 — 156 points, 60 comments) Street-Legal Jet Powered Volkswagen Beetle https://news.ycombinator.com/item?id=5384390 (March 15, 2013 — 6 points,…
How on earth is it street legal to emit a high-pressure plume of jet exhaust behind you?
But it is very hot so exhausting it close to the ground or people is a serious problem.
How did Jay Leno not get this car on his TV show when he had it? He still is posting episodes to YouTube so it is still possible.