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.
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.
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.
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.
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.