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Ron Patrick's Street-Legal Jet Powered Volkswagen Beetle (2006)

ronpatrickstuff.com

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Re: Ron Patrick's Street-Legal Jet Powered Volkswagen Beetle (2006)

#131

Post by RachelF »

hrichards wrote: post #40

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 worked for a company that did this in the 1990's. Small gas turbine, the size of two show boxes (200hp) powering a generator, which charged the batteries and/or electric motors.

The advantages are efficiency, low weight and no gearbox is needed, as the turbine spun at over 100,000 rpm and the generator was fine with that.

The main disadvantages were noise and turbines need more maintenance than piston engines. No LiIon batteries back then either.

The project only built 1 finished prototype.

Re: Ron Patrick's Street-Legal Jet Powered Volkswagen Beetle (2006)

#133

Post by gehwartzen »

shortcake27 wrote: post #125
mindslight wrote: post #32

Earlier quoted context omitted.

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…

> a single engineer personally adding a jet engine to his car while seemingly being very in touch with the dangers of operating it 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…

> What if a non-engineer who doesn’t understand the dangers makes this type of modification?

This hasn’t happened afaik in the last 15 years. I assume any non-engineer who doesn’t know the dangers also doesn’t have the technical know how to build this. Also the cost is several hundred thousand $.

History seems to indicate it’s a non-issue.

Re: Ron Patrick's Street-Legal Jet Powered Volkswagen Beetle (2006)

#134

Post by taneq »

KennyBlanken wrote: post #91
usrusr wrote: post #54

Earlier quoted context omitted.

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…

The bit about the naval use and efficiency isn't quite accurate. The issue isn't that they're not efficient. It's that they are only efficient at high power level, and the minimum power level they're efficient at (and even their minimum power level, period) - is quite high. To compare: Britain's current aircraft carrier has four diesels that total 40MW...combined those diesels equal one of its two 40MW turbines. This…

Then wouldn’t they just have a 5MW turbine and run it at its peak efficiency?

Re: Ron Patrick's Street-Legal Jet Powered Volkswagen Beetle (2006)

#135

Post by symmetricsaurus »

hrichards wrote: post #40

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…

Volvo did this back in 1992 but only as a concept vehicle https://en.m.wikipedia.org/wiki/Volvo_ECC

Re: Ron Patrick's Street-Legal Jet Powered Volkswagen Beetle (2006)

#136

Post by mschuster91 »

Animats wrote: post #115
hrichards wrote: post #40

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…

It's been done a few times, as listed here. One not mentioned was someone in Southern California who got an old aircraft APU (probably a Solar T-62[1] or similar) and made an electric hybrid back in the 1980s. The APU charged the battery, and shut down when the battery was full. Worked OK, apparently. The trouble with turbine engines is that, below bizjet size, they don't seem to get any cheaper. Not for lack of tryi…

> The trouble with turbine engines is that, below bizjet size, they don't seem to get any cheaper.

That's because of the lack of demand. GA is extremely conservative, most designs date back to the 50s-70s and the more modifications you make to a design the more extensive and expensive certification becomes. They're still flying with leaded fuel, many decades past the removal of lead in car fuel, because up until last year there hadn't been a certified alternative (and the one that is is not suspected to be readily available until 2027+).

For a jet engine powertrain on a plane the size of a Cessna, you'd need to redesign the whole frame, you'd need to design appropriately sized engines and maintenance procedures, and you'd need to re-train all the pilots. Before that happens, GA will go electric.

Re: Ron Patrick's Street-Legal Jet Powered Volkswagen Beetle (2006)

#137

Post by dahart »

lawlessone wrote: post #12
mindslight wrote: post #8

Earlier quoted context omitted.

We live in a society where things are legal by default. Why would adding a jet engine to a car be a priori illegal? If he harms somebody or otherwise causes damage, that itself is what's illegal and he'd be liable regardless of motor vehicle regulations. If this mod became a larger trend, especially consumer-available, then regulations would be implemented to head it off. But for a few lone instances it's not particu…

I am not in the US, but where i am afaik anything that modifies the car like this would have to go through some sort of recertification process. It would be perfectly legal on private property but not public roads

I’d guess that’s true in the US too, if you modify the engine or transmission or exhaust system, etc. But adding something to your car without modifying the existing systems has no regulation and no certification process, which he sorta talks about in the article re: police inability to enforce. As long as there aren’t other laws you violate, hanging a big fan out the window might not count as modifying the car.

Re: Ron Patrick's Street-Legal Jet Powered Volkswagen Beetle (2006)

#138

Post by zdragnar »

TuesdayNights wrote: post #49
hrichards wrote: post #40

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…

Arnold Schwarzenegger’s Hummer from the early 2000’s is setup like this — 100mpg with bio-diesel. I think this is the original article I read about his car’s creator, Johnathan Goodwin, from years ago. https://www.autoblog.com/amp/2007/10/20/biodiesel-turbine-su...

Per the article, he claimed the Hummer would get 60, the 100 number was aspirational based on ideas he had for future designs.

(Still pretty awesome. If it didn't likely cost more than what truck is worth I'd want it too)

Re: Ron Patrick's Street-Legal Jet Powered Volkswagen Beetle (2006)

#139

Post by zoomablemind »

Fun read!

I would rather not follow a car like that on the road, hell, even driving by it.

The looks don't signal the intent. Guess what will it do next when either light starts blinking, or both? There is no known signal for kicking on the jet engine! From the back it looks like a gigantic cannon too, BeachBuggyRacing kind.

Just for kicks, I'd also put a "Student Driver" decal on the rear window :).

Re: Ron Patrick's Street-Legal Jet Powered Volkswagen Beetle (2006)

#140

Post by p1mrx »

jgable wrote: post #112
hrichards wrote: post #40

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…

Wrightspeed did this a while (10 years?) ago. It looks like they have since pivoted to fully electric powertrains for buses, but when they first started they were doing range-extending hybrid powertrains for heavy trucks. I found an article the describes the system at the time: https://www.e-hike.net/tr/content/wrightspeed-unveils-new-turbine-range-extender-medium-and-heavy-duty-electric-powertrains-30 With a range-e…

Video of a Wrightspeed truck: https://www.youtube.com/watch?v=sIAosHyqARA
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