Wow so many haters! I know aviation is full of cynical old people but I didn't think it was this bad -- where's the excitement for something trying to revolutionise GA the same way the RV's did for owner-operated fixed wing.
Disclosure: I have an order in for this in the low 300's. It's up to 500 orders now .I don't care if you get one or not - I just want to explain a bit more about this project.
I know this project intimately well after watching every video (there's an owners app that has about 20x more content than on YouTube, although the last couple of monthly updates on YouTube are fairly good), and spending 10 days in-person at the Hill development centre consulting with some software stuff. This project is 100% happening. Jason Hill is probably the smartest person I've ever met and knows his helicopter inside out and is just as excited about door hinges as he is about rotor shaft modes of vibration and nickel super-alloy metallurgy. Also a solid beer drinker (but not as good as an Australian ha ha)!
Jason told me small engines are actually difficult to do well (read: thermal efficiency, lightweight) compared to large ones. He has some good videos about the challenges of modern (efficient) turbines like making sure the pressure/temperature distribution of the compressor casing is modelled along with blade tip lean at 60,000 rpm to make sure the tip clearance remains as low as possible, which is where the efficiency comes from. Really difficult stuff, but he's basically hired half of former Rolls Royce/turbo-machinery-industry for all this stuff & finalised most of the designs and already stamping out parts. The engine has no accessory gearbox but instead a 10kW starter/generator on the cold section (basically a bit that pokes out and a fixed stator around it). Epicyclic gearbox designed to modern standards 30mins dry. 400hp max continuous, 440 takeoff (5mins 2x/hr), 500hp (30 seconds contingency 2x/hr).
Fuselage is probably where half the big gains come from: he's got some former F1 composite guys that have made a single piece "monolage" from laid up dry-cloth impreg with resin under bag vacuum - you can pick up the 1/3 scale model with 1 finger. The design has had to change to add more structure to the roof (less overhead window) so some early comments about this were correct. Lightning mesh. They are just about to do the first full-scale prototype.
Hub is fully articulated using elastomeric bearings, which have degraded failure mode (rubber crumbs away over time) and held in compression. He said these are 13k euros each to buy from Big Aviation™, but this is the kind of stuff he can just make himself with sandwiches of metal & rubber and some effort. Rotor is going to be composite with twist & planform distribution and tapered tips for optimum efficiency. The whole mast is cowled really tight which is apparently the key to reducing drag.
Performance wise it's all on the website and public videos: max gross (800kg payload) gives a vertical 500fpm takeoff at 10,000ft ISA+15. Ducted fan tail rotor is huge giving authority in 35kt wind from any direction. 5hrs range 700NM is just epic (with 3 large blokes payload). And if it goes faster than 140kts (which he is incredibly tight lipped about, but says the drag is significantly below budget, so 140kts is possible on much less than 400hp max continuous, meaning it could probably do more like 150, 160, ... hopefully higher!! at MCP) which would make the range increase significantly too. Or take 3hrs fuel and 5 big blokes and go 500 NM, vertical in/out of anywhere basically.
Haters gonna hate but for the rest of us with orders in, it feels like massive information asymmetry here - we know something others do not. Instead of ****ting on projects like whining primadonnas, we actually spend time doing research, and if there's no blockers - lock in the early-bird price discounts! Sure there will be some issues & unknown-unknowns, but from what I can see so far it's bang on schedule, on-price, exceeding performance margins and I genuinely think is going to revolutionise the light helicopter market. I think everybody is over-estimating the risk for what is basically just a conventional helicopter design using modern aerodynamics and manufacturing techniques by some of the smartest people I've met.