Hill Helicopters HX50
Under the "Robinson R66 (merged threads)" thread, I had made a comment that in the Hill Helicopters HX50 'unveiling' videos (
), Jason Hill discusses use of 'fences' fitted to the horizontal stabilisers. Agile responded in part:
I have watched the video again and the stabiliser fences come into view from about 18:56 onwards with Jason describing their function from 19:38 onwards: "...that's about aerodynamics and drag, because we keep the flow attached from the front all the way to the back we get a relatively thick boundary layer building up as we go from front to back of the aircraft... We don't want that contaminating the leading edge of the horizontal stabiliser, tripping the flow around there and driving the performance of this. So we put fences there to keep that [boundary layer] separate".
So as Agile suggests, does the Hill Helicopters flow analysis properly take into account that there are three main rotor blades each thrashing through the air above the fuselage causing significant undulations in the flow field around the helicopter? I wonder if this causes flow separation no matter how smooth and 'appendage free' the fuselage may have been kept in front of the horizontal stabiliser? And what about the undulating and turbulent flow field from the main rotors directly striking the stabilisers? How has that been modelled? In short, are the fences adding any real value?
Don't get me wrong: I would never contemplate designing a helicopter. They are complex far beyond my comprehension.
I have doubts that anybody understand the flow pattern on the tail of a rotorcraft. You got the induced flow from the main rotor, possibly the interacting flow from the tail rotor, and then the forward air flow. That sounds like a big whirlwind shake to me, Hills and the HX50 treat it with aerodynamics principle akin to a high performance glider, well I don't buy it. last time I heard, CFD on a rotor system is still a developing science due to the complexity of the flow interaction between blades (tip vortices) all that in a moving frame of reference...
So as Agile suggests, does the Hill Helicopters flow analysis properly take into account that there are three main rotor blades each thrashing through the air above the fuselage causing significant undulations in the flow field around the helicopter? I wonder if this causes flow separation no matter how smooth and 'appendage free' the fuselage may have been kept in front of the horizontal stabiliser? And what about the undulating and turbulent flow field from the main rotors directly striking the stabilisers? How has that been modelled? In short, are the fences adding any real value?
Don't get me wrong: I would never contemplate designing a helicopter. They are complex far beyond my comprehension.
Until the HX50 gets in the air properly they won't really know if all the computer-modelling is correct or not
Look at the issues Augusta had with the A139 tail rotor when it was released, etc And this is major manufacturer with proper factories, design teams, for a certified aircraft.
Yet another AW139 tail incident at Gulf helis
Look at the issues Augusta had with the A139 tail rotor when it was released, etc And this is major manufacturer with proper factories, design teams, for a certified aircraft.
Yet another AW139 tail incident at Gulf helis
Avoid imitations
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I noted the “Helimove” option. All of this adds complication and importantly, weight. As well as the actual equipment a large capacity battery will be needed to power it. There are ways of safely moving a helicopter in and out of a hangar by remote control without fitting anything to the aircraft.
The RAF were offered a wheel drive system for the Puma, decades ago. It didn’t work well and was not fitted to squadron aircraft.
The RAF were offered a wheel drive system for the Puma, decades ago. It didn’t work well and was not fitted to squadron aircraft.
If you want to see just how well he understands his customer base and the helicopter manufacturing industry, watch Ep62 of the helicopter podcast:
Originally Posted by [email protected]
I have no skin in the game, I will never have enough spare cash to buy one even if I wanted to (I don't).
My criticisms come from knowledge of helicopters (of which I have some) and not my knowledge of investing (of which I have none).
If he does it, then fair play, but I don't think what will be produced will be what was originally promised and the investors will have to suck up the shortfalls in capability and performance.
My criticisms come from knowledge of helicopters (of which I have some) and not my knowledge of investing (of which I have none).
If he does it, then fair play, but I don't think what will be produced will be what was originally promised and the investors will have to suck up the shortfalls in capability and performance.
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Yeah, just see all the threads on this forum from ignorant non-owners wondering why anyone would buy a $500k R44 when a $5 million A-Star is better. They just don't get it.
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If you are placing an order now (eg number 1,201) when on earth are you hoping to get an aircraft?
If proper production starts in 2026, even with an average of 250 aircraft built per year means ..the year 2031 ?
If proper production starts in 2026, even with an average of 250 aircraft built per year means ..the year 2031 ?
The other question is why Hill keeps the order book open. Any normal business would close it and focus on delivering the promises. And charging more once they have delivered. But we all know why he keeps the book open. However for many it's just another example of 'doing things differently/vertical integration ' blah blah.
Had Hill charged Ł1m, announced 100 initial build machines and had a proper business plan in place, I would have been all over it. To be fair I don't think he is a scammer, but he does think that he is so intelligent that he can solve problems that no one else can. Engineering, planning, finance, HR...you name it.The depositors are betting that he is right. Personally, I doubt it. But I wish you all the best.
And in case Shagpile is about to froth off at me, I have owned helicopters for 25 years, all paid for with cash, not credit.
This HX50 is just hype. A good one.
But I doubt if they can deliver these best technologies at low price. I know they have justifications but the likelihood of them not meeting these are just so high. I mean, foremost, everything is original from bolts to airframe to avionics. All are original Hill Helicopter design. So just how are you going to do that and maintain a low price? The total opposite of the best practices now that the major components are better sourced from known and tested brands.
But I doubt if they can deliver these best technologies at low price. I know they have justifications but the likelihood of them not meeting these are just so high. I mean, foremost, everything is original from bolts to airframe to avionics. All are original Hill Helicopter design. So just how are you going to do that and maintain a low price? The total opposite of the best practices now that the major components are better sourced from known and tested brands.
Last edited by Senior Pilot; 27th Feb 2024 at 00:50. Reason: All in English, please
And you've hit the nail on the head Crab. Although you are obviously a very experienced helicopter pilot and no doubt have been around the industry a long time, I suspect you've never actually owned a helicopter yourself, nor had to pay for the maintenance of one out of your own hard earned. (Please open disclosure on this and set the record straight, you are a very vocal critic and its important for context) The frustration with the existing manufacturers in our small world of helicopters is a key driver of why Hill started the HX50 in the first place. Cost of entry is high, but the real killer is the maintenance costs, and calendar life limits that make helicopter ownership prohibitively expensive for private owners. This is why he already has 1200+ orders without even having anything flying yet. I think it's fair to say that on this forum, despite our differences, we all love helicopters and flying. Some of us just want to have a shot at owning one under reasonable financial terms. Is Hill the answer? Time will tell. But there's no one else doing anything significant to address the issue, so why not get behind it and focus on the positives? He's making progress....
I haven't owned my own nor ever will but I know quite a few owners and fly for one who has a lot of ex-military helicopters - if you want safety for you and your family, you pay the maintenance costs.
I am not defending the OEM prices for spares but they just follow what the car manufacturers do - lower the initial cost to get you to buy and then drag back some of that discount on spares and servicing.
Why do you think that Dr Hill is going to be any different or can't you see past the shiny shop window and politician-like promises?
Will he shake up the industry? I doubt it.
Will he make a half-decent helicopter for rich guys to pose in? Very probably.
Will people have to wait for longer than they thought for it? Almost certainly.
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Originally Posted by [email protected]
Will he shake up the industry? I doubt it.
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Oh my god, Hill is trying to incinerate a dumpster with a raspberry Pi processor development kit, out of the back of his garage. The Safran guys must have so much fun passing that video around at lunch break.
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If this is the stage he’s at now, it just shows how much work is left to do and how long it will be before we see a fit for purpose, production quality engine. As for the back drop… 
Not the greatest contribution from his marketing team!
Not the greatest contribution from his marketing team!
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Do people really think that this aircraft will be flying in 2024? That's my hat safe if not - my shoe was already saved by the lack of flight in 2023.
More like 2026...if at all.
More like 2026...if at all.
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H99, I'm struggling to understand whether you are a sceptic or a Hilleiver?
But constabtly cutting ans pasting from the Hill website is wasting everyone's time. After all, here's a quote for you:
"First flight is on schedule for 2022, followed by first customer deliveries in 2023."
Read more at https://www.helihub.com/2021/06/15/o...nd-deliveries/
So how did that work out, exactly?
Anyway, I have fixed it for you
But constabtly cutting ans pasting from the Hill website is wasting everyone's time. After all, here's a quote for you:
"First flight is on schedule for 2022, followed by first customer deliveries in 2023."
Read more at https://www.helihub.com/2021/06/15/o...nd-deliveries/
So how did that work out, exactly?
Anyway, I have fixed it for you
Last edited by 206 jock; 1st Mar 2024 at 14:48. Reason: Includes picture
A few days ago, they showed a test rig for a combustion chamber working; the combustion chamber was burning and doing its thing. So progress is being made.
But even if the engine and gearbox never appear, what is to stop Hill from buying and installing existing solutions from other manufacturers?
But even if the engine and gearbox never appear, what is to stop Hill from buying and installing existing solutions from other manufacturers?
Last edited by DroneDog; 1st Mar 2024 at 14:38.