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Comment by Ecco | Hacker News Reader

It sounds like it's electric powered. As much as I love brushless motors, I think a model of that scale and quality would have deserved actual jet engines.

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Tyler Perry owns the airplane and the property. He has said that he does not fly turbines due to the fire risk in a crash. His property is surrounded by forest. If he were to cause a forest fire, the negative publicity could have a major impact on his career.

That property is gorgeous and Tyler pulls out all the stops for his builds. That channel (Ramy RC) has quite a few of them.

The closeness of the trees to the runway kept giving me extreme pucker ...

Thank you for inadvertently answering a question I had, which was who owned that estate.

I'll preempt future comments that lithium batteries can catch fire too. I agree with that statement but still think the risk is mitigated by not going with gasoline fuels.

RC-scale tiny turbines are sort of a boondoggle. They are loud, dangerous, and quite frankly reliability disasters. Expected component lifetimes are in the hundreds of hours, most folks overhaul them every 20-50 hours of use, and they fail in the air with shocking regularity (just check youtube).

It's one of those "impressive that it works at all" kind of things. If that's what you want to see in the air, then do it. If you want to watch your one-off custom plane that represents hundreds or thousands of hours of labor fly, you push it with a fan.

Is that a physics thing, or just jet engines are hard and RC budgets aren't very big?

I wonder if it's not a: "maintaining this kind of engine is a heck-of-a-lot of work and is why there are so many aviation regulations and the reason engine overhauls are forced and cost millions-of-dollars" kind of thing.

Mostly physics. It's hard to do small jets, mostly because small things get too heat-stressed

I sorta watched a guy trying to build a hoverboard out of 50-kgf jets, it was crazy, hilarious and didn't go anywhere because flying a backpack of kerosene on four totatally unreliable jets ain't much fun in the end. They also cost about $5K each at the time.

Just yesterday, someone posted a link to a Veritasium video[0] explaining how a jet engine internal temps of 1500°C work when the components have a melting point of 1250°C. I couldn't imagine doing that at a small scale by hobbyists.

[0]https://www.youtube.com/watch?v=QtxVdC7pBQM

Yes, and those small engines might work for a bit, but then they just burn out, this is inevitable.

If you build an A380 like here you sure don't want to use them unless you want to film it burning down spectacularly.

Sounds perfect for Hollywood practical effects vs boring CG

One can wish.

Besides, thrust control is shit even on their big brothers, on those, it was like throttle down - flameout, throttle up on the other two - flameout, oh crap, thank god we're doing tethered tests.

Gas dynamics on these scales are tricky too. Electric is the way to go for this.

There is an actual airplane (multi engine) that uses these:

https://pilotweb.aero/aircraft/flight-test-colomban-jet-cri-...

If it had been gas-powered motors, I would have agreed with you. The electrics sound close enough to my ear like actual jet engines though.

AFAIK the only existing small jet engines for RC planes are much too small for this one.

There are certainly turbines available that could power the model. He chooses not to.

They've been scaling these things up over the past decade. The JetCat P1000 can exceed 200lbs of thrust.

What they really for this kind of build are RC turbofans, which are extremely uncommon. This thing puts out over 300lbs of thrust at full throttle:

https://www.frankturbine.com/en/FT1500.html

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