I'm a private pilot and aircraft mechanic in Canada. I wish we were neighbours. I thoroughly enjoy watching your channel please share more. Best of luck on everything.
Good morning from Washington state USA i love your copter man im dreaming to make one some day could i come to visit your place i had tiny shop i worked on my car but i don't have machine shop, i wod like buy parts you made. Thanks
Adding a stabilisation augmentation device like the bell stabilizing bar to the rotor head could improve the stability and the handling qualities in hoovering and also make translation flight more achievable.
Hi, the bell stabiliser bar is connected to the blade feathering pitch links. I don't have blade feathering on this design. The rotors are fixed in pitch so unfortunately I can't add such a bar. It is possible to raise the rotor to a higher elevation and that might help stability.
Thanks very much Cam. 😊 interesting you chose the same generator. I expect in the end I will have to go for a belt driven fan but it should point me in the right direction with regard to sizing. I'm getting as much weight as possible out of the machine, at least then there will be an option to add a bigger radiator or add another. Your fuel pumps and ECU take a bit of power don't they! Doesn't sound like there will be much left for the big amp and stereo. 😉
Well, collective pitch is what I would choose next time. Fixed pitch is certainly less sensitive than collective, so in calm conditions it's easier but as soon as the wind picks up you want collective for the quick reaction time.
@@Ben-Dixey it’s that rotor speed staying at a constant high rpm gives you the stability. Much like a spinning top. If you slow down the top it wants to topple over and become wobbly.
I can't agree with that I'm afraid, there is no gyroscopic stability in any helicopter that I can think of. They are inherently unstable. The only exception might be the hiller flying platform, but the stability in that machine is not gyroscopic.
@@Ben-Dixey A co-axle helicopter is probably the most stable flying vehicle. So much so that they are sold in toy stores to kids. You don’t seem to know the flight characteristic of a helicopter meanwhile you’re building one for yourself to fly. Find a RC version and fly it first would be my suggestion. But hey to each their own.🫡
The toy rc coaxial helicopters are stable because they have stabiliser bars. You'll notice that weighted bar attached to one of the rotors. That is why they are easy to fly, not because they are coaxial. Coaxial helicopters are no more stable than any other configuration.
Hi, yes shorter blades would significantly reduce lift, efficiency increases with longer blades and reduces with shorter ones. The Jetson one for example would see an increase in flight duration powering a coaxial rotor like mine, over the small props.
@@Ben-Dixey ok thanks , do counter rotating blades create like wash from each other? Would they be more efficient spaced apart instead of stacked on top? Sorry about all the questions but I often dream of building a flying machine of some kind haha
You would think that rotors spaced further apart on a coax would be more efficient but that's not the case. There is a certain distance where lift increases, I believe that to be 10% rotor diameter. I don't know the aerodynamic reasons behind this but i suspect it's something to do with drag from tip vortices. You might have seen contrarotating propellers this removed torque on the aeroplane fuselage but also increased thrust but there is a critical distance between the props for this to happen. I of course share your dream. 👍
Hi, my engine overheats too. I have put on a bigger electric fan but I think a belt driven fan might be needed in the end and possibly a bigger radiator, we are asking a lot of these engines and keeping them cool is a challenge. I'm reducing weight in the machine so I can add weight in extra cooling. Getting a helicopter to fly is one task, keeping it flying is another.
Nice work as usual! I have paused on my Helicycle for a couple of months due to injury. I am getting better and hopefully going to get back on it very soon. Meanwhile, we have a hanger and helo pad under construction on a beautiful piece of property we own in a rural area not far from my house. I am going to make a video of it at some point. Anyhow, all the best to you and keep it going!
Hello my friend, Sorry to hear you have been injured and hope you can get back on your helicycle soon. The Helipad sounds very exciting, a video of that would be great! look forward to more videos. 👍
I think this is a brilliant project and I applaud the simplicity of design and your pioneering spirit !! :) Having learned to fly helicopters and taught myself to fly paragliders I can imagine what a daunting challenge you have set for yourself, I'm glad to see you've decided to take some heli lessons at least, expensive but fun !! :) There are a couple of things that concern me regarding this design though... firstly are the single drive belts to each rotor, I've seen these chip out and fail in short order... but adding a second pair would add weight so I understand this decision. Secondly fast forward flight with a fixed pitch rotor head can be challenging with tendencies to balloon and roll etc. not to mention excess flapping on a coaxial could lead to a rapid unscheduled disassembly. Fly bar weights on each rotor head could alleviate some of the ballooning etc. but this adds weight and complexity as you would need to include swash plates as weight shift would no longer work as that is effectively what you are using now. No doubt you've considered all this, it's unlikely anyone gets as far as you have without a great deal of consideration ! :) An intermeshing rotor system might be an interesting solution to the blade flap and clap concern if fast forward flight gets on to the bucket list of things to do ? I suppose the trick is to not fly faster or higher than you are prepared to crash ;) Have you thought about maybe getting a qualified helicopter test pilot to fly your machine ? Would make for a great video and no doubt be very educational for you :) Anyhow, I watch your progress with fascination and hope of success ! Best wishes.
Thanks for this message, you taught yourself to fly paragliders ? Wondering how you did that! The belt concern you mention you say chip out, is that teeth being chipped off ? Yes having single belts to each rotor is a single point of failure and is of concern. I've not heard the term ballooning? The roll in forward flight I think could only happen without teeter hinges but only on a single rotor ? Coaxial should cancel? Excess flapping is another concern for sure, fast forward flight seems a long way off and I'm not sure it would be attempted. As you know lift increases with speed and to keep the machine low to the ground would mean precise control of throttle in my case. I'm not sure if the throttle would respond fast enough for this type of flying. 🤔 certainly not for any abrupt manoeuvres I would suggest. The aim with this machine was mostly hovering but I did hope to travel at some small forward speed and I agree keep things low and slow would be the sensible operating envelope. The intermeshing syncropter type arrangement would be a great project, I do like that configuration and lift for the same blade diameters I think would be improved. A man called Dick Degraw built one th-cam.com/video/9TUbR5Zogv8/w-d-xo.html The guy is a genius. I have considered asking a pilot to fly it but decided I wouldn't put at risk another person in my largely unproven machine, but it would certainly have been a very interesting experiment.
@@Ben-Dixey .. re paragliding, I got myself a wing and went to some small hills out the back of my house where I couldn't hurt anyone else and learned the hard way, incrementally. Nearly came unstuck a couple of times but stuck with it. After a year of rogue flying I;d acquired 33 hours at which point the guilt got to me and I went to Airworks to get qualified which I did in one day :) You're right, roll in forward flight would largely be cancelled out in coaxial, although you running a degree higher of angle of attack in the lower blades so there would likely be some roll, but yes, you can tell I'm used to flying single rotor machines. Ballooning is unwanted pitch up, which you've demonstrated in your videos when an unwanted gust hits your heli in the hover. This is what happens when you achieve fast forward flight and one needs to be quire assertive on the controls to counter act it. If you stay below the translational lift speed (20mph ish) it's lees of an issue. Regarding the belt drives, I once had a heli lesson cancelled because one of the belts had chipped out on the back side not the tooth side, luckily they have two belts, Not sure what the life time of these components are but might be a good idea to find out and replace every 50 to 100 hours of flight ? One nice thing about the intermeshing types is that they can be gear driven much more easily with a number of other advantages too, including the ones you mention. The blades could use equal pitch angles, a universal joint could be fitted to just beneath each rotor head to effect cyclic control thus eliminating the need for the whole engine and rotor assembly to be gimbled which would improve the weight shift aspect of control. Considerations for the BTD Mk2 perhaps ? :) Another thought occurs, I wonder if the safety training skids are too wide ? I can't help but feel they might be more of a hindrance than help, aside from the extra weight etc. At that length, or should I say width, they look like they would be easy to bend and buckle thus less resistant to tipping compared to if they were a little shorter, as wide as the skids are long, perhaps two thirds of their overall current width, sticking out from the main skids about 50% of what they are now ? Putting balls on the end is a good idea, it's what we do for people learning to fly RC models :) But these training skids do wobble about a lot and adversely effects control, certainly for the models and kind of looks like the same thing is happening with you in your videos... just a thought. Speaking of models, perhaps getting a simple electric fixed pitch RC helicopter that's easy to maintain of at least an 18" rotor diameter might be a useful learning tool for understanding the flight characteristics of fixed pitch helis ? ... I've had a few such models and some fly quite well, none as good as a full collective head but i did learn a lot about fixed pitch flight without the risk of being in it :D Different from the real thing of course because one needs to think further ahead than the models but never the less, good fun at the very least :) Finally regarding asking another pilot to fly your machine, I understand your reservations completely and I wouldn't invite just any pilot, you want a qualified test pilot, one who understands how to evaluate the risks and take an incremental and disciplined approach, who can stay calm under pressure etc. The UK equivalent of Chuck Yeager :D The CAA would likely have a list of such people who might be interested your project ..... Even if they just looked your machine over without flying it I have no doubt their insights would be fascinating and would make a good video. It could also be useful to you to have them watch you fly it in person. Just spit balling ideas, I'm trying to put myself in your shoes :)
Super comment. Thanks again. Your teaching of yourself to fly a paraglider certainly parallels my project. We obviously have a similar outlook but glad you got qualified. Ballooning would that also be called rotor flap back ? Interesting comment on the effect of the differential pitch between rotors causing a roll. I would still expect the teeter hinges to accommodate this which would result in blade tips coming closer together. If a visual inspection of belt condition is enough to go by then I'm quite happy. The machine at the moment spends a very limited time in the air compared to in the Workshop being inspected. I think your suggestion to change belts after a number of hours is sensible. The only slight snag is they are £500 to replace. Great point on the skids, it was mentioned to me that they cause instability in models but i couldn't understand why, now it makes perfect sense. I think we need to take into account the ratio of weight on the models extended skids to fuselage weight compared to mine but I did plan to reduce the skids from 4m to 3m for the next test. Buying a fixed pitch coax model is another good suggestion, I will have a look, do they have stabilising gyros though ? Test pilots insights would be great 👍
@@Ben-Dixey ... There were a few reasons I taught myself to fly paragliders, I could no longer afford to fly helicopters or anything else and missed flying too much not to do something about it and the route I took was the only way for me to get airbourne, plus I wanted a taste of the pioneering spirit for myself. Having been through it I would never recommend it to anyone but if they insist on going auto-didactic then rule no.1 is do it in such a way you can't hurt anyone else and to take an incremental approach, keep your mistakes small enough to learn from etc. That said, having flown both and more the challenge you have set for yourself stands far taller than mine !! Yes I think flap back might be the correct term for ballooning, planes can do it too but for different reasons. Regarding the belts a preflight check is mandatory as with everything else regarding the machine naturally :) £500 is quite a lot for a pair of belts though, are they aircraft quality ? Would be interesting find out what the manufacturers suggested lifetime is... and to find out what the belt life times are for something like an R22 helicopter and use that as a guide perhaps ? If you change them every hundred hours that's on £5 per hour extra, if one of them pops there's half a chance you total the whole machine. However they look reasonably wide although if I remember rightly one has teeth on both sides and seems quite skinny .... I am of course speculating from videos at a distance here, you sound like this is something you've considered seriously and done your homework etc. The issue with the skids is about resonant frequencies which cascade throughout the mechanism, the shorter the extensions are, the higher the frequency and they will become stiffer as the moment area of the cross section improves. They're basically like low frequency tuning forks and if they're in tune with the engine and rotors you get a resonant frequency that can break things, like the opera singer with a wine glass. But also the wobbly weight will mess with the controls too, imagine putting a wobbly weight that sticks out the front of the handle bars on a bicycle, it would definitely make steering harder, especially over a bumpy road. I've not seen any decent sized RC fixed pitch coax models and all the small ones have a 45 degree lead on the flybar which stabilizes very well in still air but completely messes things up in wind or fast forward flight. My suggestion was for a single rotor fixed pitch. But make sure you get one with minimal camber on the rotor blades. The old school Hornet I had from years ago flew well enough to explore a wide regime of flight. And yes, they have gyros for the tail at the very least, kind of unflyable without them really. These days you can get some models with gyros for all axis's but I'm not keen on that because they always feel like it's doing the flying and not you. But you can get the small ones for around £40 that will fly indoors happily but they are a toy, fun but limited. As for test pilots, I bet you a pound to a pinch of shit there's more than one out there who would be fascinated with what you have created thus far !! :) Cheers for the link to Dick DeGraw's heli, I did some searching and found a brief video of it taking off, looked really smooth and very controllable ! th-cam.com/video/Q6mDK9XhklE/w-d-xo.html And here's some more of his Jump Take Off Gyrocopters ! awesome stuff, very clever guy ! th-cam.com/video/y_COkkFuchA/w-d-xo.html th-cam.com/video/t6xjCUVuUzg/w-d-xo.html
th-cam.com/video/0MDtdLv99WI/w-d-xo.html th-cam.com/video/wk0AKpkaFx0/w-d-xo.html th-cam.com/video/a882megKhVM/w-d-xo.html Anyhow, I don't know where abouts your farm is but if it's anywhere near East Sussex I'd love to drop in for a cuppa and to see the machine in person, cheeky of me I know but design, vehicle design and specifically aircraft design has always been a favourite subject of mine but I never got beyond exploring it with RC models, another of my self taught endeavors but then flying for me is the only real magic in the world ! :)
I think we are on the same page. The belts were sized using gates drive design software, I originally phoned them for advice but told them it was for a helicopter. At this point they ended the conversation. Hadn't thought about liability in this situation. So I went online and found their software. I'll have a look at the parameters but I'm sure it would be set at a sensible operating lifespan. The only thing is I'm now running the belts at a smaller drive pulley diameter than recommended and about to decrease this even further. I suspect this will reduce belt life. No doubt a breakage would have a catastrophic result but then there are quite a few components that can do that. The belts haven't been at the top of my list of worry's in this machine. However I had better run the numbers again and see what info I can obtain with the smaller drive pulley. The bottom belt is wider for the simple reason that's all that was available in the double sided version, it should be stronger than the narrower one. If buying the belts again I would choose shorter ones and bring the weight down out the rear of the tilting head. That would mean less counter balance in the front needed. The sch2a uses double sided poly v belts, much lighter set up than mine. I wouldn't mind going this route. I can now understand the effect of wobbling weight in extended skids. Will Definitely reduce the length but not by too much yet, gradual reduction I think will have to be the way. Dicks jump gyros are amazing I tried to contact him via Facebook but no response yet. He must be in his 80s by now. I'm in north Devon about 4hrs from You ? If you're ever this way let me know. btdixey@hotmail.com is my email.
Reminds me of the small Helicopters from Far Cry 4. Keep up the good work, cant wait to see your channel explode when you upload the field exploration video. Where exactly are u from, somewhere down south I assume lol?
Bearing walk out may be symptom of drive shaft dynamics. Possibly boot distortion unbalance or even shaft bending flexure. High speed cam best way to see what's going on. Play it safe with engine rpm as its original design duty cycle might not be as demanding as a helicopter in hover. Recommend wire lock nuts to be sure that you are sure that nothing is coming loose... google aircraft hardware suppliers to stop viscous TH-cam algorithm deleting posts about flight safety. 🙄
I remember reading that performance quote and it brings hope to the project. In the video the take off weight is 240kg that means around 44hp is being generated by the engine. quite short of the 60hp the engine is rated for but blade pitch is 6.5 degrees lower rotor and 5.5 degrees top rotor. 7 degrees I think is max lift/drag for 0012 blade, I'm confidant there is more potential in this machine.
I Made a set of washed out rotor blades for my helicopter (6 deg twist) the performance increase was noticeable. Ps send me your contact details and we can discuss further
I'm a private pilot and aircraft mechanic in Canada. I wish we were neighbours. I thoroughly enjoy watching your channel please share more. Best of luck on everything.
Hi and thanks for the very nice comment. 😊 your job and hobby sounds great! I would also love to visit Canada
Good morning from Washington state USA i love your copter man im dreaming to make one some day could i come to visit your place i had tiny shop i worked on my car but i don't have machine shop, i wod like buy parts you made. Thanks
Adding a stabilisation augmentation device like the bell stabilizing bar to the rotor head could improve the stability and the handling qualities in hoovering and also make translation flight more achievable.
Hi, the bell stabiliser bar is connected to the blade feathering pitch links. I don't have blade feathering on this design. The rotors are fixed in pitch so unfortunately I can't add such a bar. It is possible to raise the rotor to a higher elevation and that might help stability.
Love your videos. I'm using the same generator but it barely keeps up with current draw from the electric fuel pumps and ECU. Keep up the great work 🙂
Thanks very much Cam. 😊 interesting you chose the same generator. I expect in the end I will have to go for a belt driven fan but it should point me in the right direction with regard to sizing. I'm getting as much weight as possible out of the machine, at least then there will be an option to add a bigger radiator or add another. Your fuel pumps and ECU take a bit of power don't they! Doesn't sound like there will be much left for the big amp and stereo. 😉
Doing far more than the rest of us!
I need to get one of those bolt shaving shop blades! Interesting viewer that allows you to inspect the tooth angles.
The blades are good but pricy. 😆 my projector I bought for £100 on eBay, absolute bargain and great for measuring stuff like this.
Variable pitch opposed to variable throttle is the answer for a more stable hover.
Well, collective pitch is what I would choose next time. Fixed pitch is certainly less sensitive than collective, so in calm conditions it's easier but as soon as the wind picks up you want collective for the quick reaction time.
@@Ben-Dixey it’s that rotor speed staying at a constant high rpm gives you the stability. Much like a spinning top. If you slow down the top it wants to topple over and become wobbly.
I can't agree with that I'm afraid, there is no gyroscopic stability in any helicopter that I can think of. They are inherently unstable. The only exception might be the hiller flying platform, but the stability in that machine is not gyroscopic.
@@Ben-Dixey A co-axle helicopter is probably the most stable flying vehicle. So much so that they are sold in toy stores to kids. You don’t seem to know the flight characteristic of a helicopter meanwhile you’re building one for yourself to fly. Find a RC version and fly it first would be my suggestion. But hey to each their own.🫡
The toy rc coaxial helicopters are stable because they have stabiliser bars. You'll notice that weighted bar attached to one of the rotors. That is why they are easy to fly, not because they are coaxial. Coaxial helicopters are no more stable than any other configuration.
Cool stuff! Can you just shorten the blades a bit to get more rpm or is that a big lift sacrifice?
Hi, yes shorter blades would significantly reduce lift, efficiency increases with longer blades and reduces with shorter ones. The Jetson one for example would see an increase in flight duration powering a coaxial rotor like mine, over the small props.
@@Ben-Dixey ok thanks , do counter rotating blades create like wash from each other? Would they be more efficient spaced apart instead of stacked on top? Sorry about all the questions but I often dream of building a flying machine of some kind haha
You would think that rotors spaced further apart on a coax would be more efficient but that's not the case. There is a certain distance where lift increases, I believe that to be 10% rotor diameter. I don't know the aerodynamic reasons behind this but i suspect it's something to do with drag from tip vortices. You might have seen contrarotating propellers this removed torque on the aeroplane fuselage but also increased thrust but there is a critical distance between the props for this to happen. I of course share your dream. 👍
you are positively crazy. Always Happy Landings.
Almost 6 1:2 minutes long yet to me it seemed like 2. I enjoyed watching your improvement on the parts AND going up little more. Cheers.
Thanks Bruce. Lovely comment
my engine heats up quickly, do you have a solution?
Hi, my engine overheats too. I have put on a bigger electric fan but I think a belt driven fan might be needed in the end and possibly a bigger radiator, we are asking a lot of these engines and keeping them cool is a challenge. I'm reducing weight in the machine so I can add weight in extra cooling. Getting a helicopter to fly is one task, keeping it flying is another.
👍👍👍
Nice work as usual! I have paused on my Helicycle for a couple of months due to injury. I am getting better and hopefully going to get back on it very soon. Meanwhile, we have a hanger and helo pad under construction on a beautiful piece of property we own in a rural area not far from my house. I am going to make a video of it at some point. Anyhow, all the best to you and keep it going!
Hello my friend, Sorry to hear you have been injured and hope you can get back on your helicycle soon. The Helipad sounds very exciting, a video of that would be great! look forward to more videos. 👍
Good work. Keep it up and I'm certain you'll get 'there'.
Regards Mark in the UK
Thanks Mark 👍
I’ve been waiting for an update :)
I think this is a brilliant project and I applaud the simplicity of design and your pioneering spirit !! :)
Having learned to fly helicopters and taught myself to fly paragliders I can imagine what a daunting challenge you have set for yourself, I'm glad to see you've decided to take some heli lessons at least, expensive but fun !! :)
There are a couple of things that concern me regarding this design though... firstly are the single drive belts to each rotor, I've seen these chip out and fail in short order... but adding a second pair would add weight so I understand this decision.
Secondly fast forward flight with a fixed pitch rotor head can be challenging with tendencies to balloon and roll etc. not to mention excess flapping on a coaxial could lead to a rapid unscheduled disassembly.
Fly bar weights on each rotor head could alleviate some of the ballooning etc. but this adds weight and complexity as you would need to include swash plates as weight shift would no longer work as that is effectively what you are using now.
No doubt you've considered all this, it's unlikely anyone gets as far as you have without a great deal of consideration ! :)
An intermeshing rotor system might be an interesting solution to the blade flap and clap concern if fast forward flight gets on to the bucket list of things to do ?
I suppose the trick is to not fly faster or higher than you are prepared to crash ;)
Have you thought about maybe getting a qualified helicopter test pilot to fly your machine ?
Would make for a great video and no doubt be very educational for you :)
Anyhow, I watch your progress with fascination and hope of success !
Best wishes.
Thanks for this message, you taught yourself to fly paragliders ? Wondering how you did that!
The belt concern you mention you say chip out, is that teeth being chipped off ? Yes having single belts to each rotor is a single point of failure and is of concern.
I've not heard the term ballooning?
The roll in forward flight I think could only happen without teeter hinges but only on a single rotor ? Coaxial should cancel? Excess flapping is another concern for sure, fast forward flight seems a long way off and I'm not sure it would be attempted. As you know lift increases with speed and to keep
the machine low to the ground would mean precise control of throttle in my case. I'm not sure if the throttle would respond fast enough for this type of flying. 🤔 certainly not for any abrupt manoeuvres I would suggest.
The aim with this machine was mostly hovering but I did hope to travel at some small forward speed and I agree keep things low and slow would be the sensible operating envelope.
The intermeshing syncropter type arrangement would be a great project, I do like that configuration and lift for the same blade diameters I think would be improved. A man called Dick Degraw built one th-cam.com/video/9TUbR5Zogv8/w-d-xo.html
The guy is a genius.
I have considered asking a pilot to fly it but decided I wouldn't put at risk another person in my largely unproven machine, but it would certainly have been a very interesting experiment.
@@Ben-Dixey .. re paragliding, I got myself a wing and went to some small hills out the back of my house where I couldn't hurt anyone else and learned the hard way, incrementally. Nearly came unstuck a couple of times but stuck with it. After a year of rogue flying I;d acquired 33 hours at which point the guilt got to me and I went to Airworks to get qualified which I did in one day :)
You're right, roll in forward flight would largely be cancelled out in coaxial, although you running a degree higher of angle of attack in the lower blades so there would likely be some roll, but yes, you can tell I'm used to flying single rotor machines.
Ballooning is unwanted pitch up, which you've demonstrated in your videos when an unwanted gust hits your heli in the hover. This is what happens when you achieve fast forward flight and one needs to be quire assertive on the controls to counter act it. If you stay below the translational lift speed (20mph ish) it's lees of an issue.
Regarding the belt drives, I once had a heli lesson cancelled because one of the belts had chipped out on the back side not the tooth side, luckily they have two belts, Not sure what the life time of these components are but might be a good idea to find out and replace every 50 to 100 hours of flight ?
One nice thing about the intermeshing types is that they can be gear driven much more easily with a number of other advantages too, including the ones you mention. The blades could use equal pitch angles, a universal joint could be fitted to just beneath each rotor head to effect cyclic control thus eliminating the need for the whole engine and rotor assembly to be gimbled which would improve the weight shift aspect of control.
Considerations for the BTD Mk2 perhaps ? :)
Another thought occurs, I wonder if the safety training skids are too wide ?
I can't help but feel they might be more of a hindrance than help, aside from the extra weight etc.
At that length, or should I say width, they look like they would be easy to bend and buckle thus less resistant to tipping compared to if they were a little shorter, as wide as the skids are long, perhaps two thirds of their overall current width, sticking out from the main skids about 50% of what they are now ?
Putting balls on the end is a good idea, it's what we do for people learning to fly RC models :)
But these training skids do wobble about a lot and adversely effects control, certainly for the models and kind of looks like the same thing is happening with you in your videos... just a thought.
Speaking of models, perhaps getting a simple electric fixed pitch RC helicopter that's easy to maintain of at least an 18" rotor diameter might be a useful learning tool for understanding the flight characteristics of fixed pitch helis ? ... I've had a few such models and some fly quite well, none as good as a full collective head but i did learn a lot about fixed pitch flight without the risk of being in it :D
Different from the real thing of course because one needs to think further ahead than the models but never the less, good fun at the very least :)
Finally regarding asking another pilot to fly your machine, I understand your reservations completely and I wouldn't invite just any pilot, you want a qualified test pilot, one who understands how to evaluate the risks and take an incremental and disciplined approach, who can stay calm under pressure etc.
The UK equivalent of Chuck Yeager :D
The CAA would likely have a list of such people who might be interested your project .....
Even if they just looked your machine over without flying it I have no doubt their insights would be fascinating and would make a good video. It could also be useful to you to have them watch you fly it in person.
Just spit balling ideas, I'm trying to put myself in your shoes :)
Super comment. Thanks again.
Your teaching of yourself to fly a paraglider certainly parallels my project. We obviously have a similar outlook but glad you got qualified.
Ballooning would that also be called rotor flap back ?
Interesting comment on the effect of the differential pitch between rotors causing a roll. I would still expect the teeter hinges to accommodate this which would result in blade tips coming closer together.
If a visual inspection of belt condition is enough to go by then I'm quite happy. The machine at the moment spends a very limited time in the air compared to in the Workshop being inspected. I think your suggestion to change belts after a number of hours is sensible. The only slight snag is they are £500 to replace.
Great point on the skids, it was mentioned to me that they cause instability in models but i couldn't understand why, now it makes perfect sense. I think we need to take into account the ratio of weight on the models extended skids to fuselage weight compared to mine but I did plan to reduce the skids from 4m to 3m for the next test.
Buying a fixed pitch coax model is another good suggestion, I will have a look, do they have stabilising gyros though ?
Test pilots insights would be great 👍
@@Ben-Dixey ... There were a few reasons I taught myself to fly paragliders, I could no longer afford to fly helicopters or anything else and missed flying too much not to do something about it and the route I took was the only way for me to get airbourne, plus I wanted a taste of the pioneering spirit for myself. Having been through it I would never recommend it to anyone but if they insist on going auto-didactic then rule no.1 is do it in such a way you can't hurt anyone else and to take an incremental approach, keep your mistakes small enough to learn from etc.
That said, having flown both and more the challenge you have set for yourself stands far taller than mine !!
Yes I think flap back might be the correct term for ballooning, planes can do it too but for different reasons.
Regarding the belts a preflight check is mandatory as with everything else regarding the machine naturally :)
£500 is quite a lot for a pair of belts though, are they aircraft quality ?
Would be interesting find out what the manufacturers suggested lifetime is... and to find out what the belt life times are for something like an R22 helicopter and use that as a guide perhaps ?
If you change them every hundred hours that's on £5 per hour extra, if one of them pops there's half a chance you total the whole machine. However they look reasonably wide although if I remember rightly one has teeth on both sides and seems quite skinny .... I am of course speculating from videos at a distance here, you sound like this is something you've considered seriously and done your homework etc.
The issue with the skids is about resonant frequencies which cascade throughout the mechanism, the shorter the extensions are, the higher the frequency and they will become stiffer as the moment area of the cross section improves. They're basically like low frequency tuning forks and if they're in tune with the engine and rotors you get a resonant frequency that can break things, like the opera singer with a wine glass. But also the wobbly weight will mess with the controls too, imagine putting a wobbly weight that sticks out the front of the handle bars on a bicycle, it would definitely make steering harder, especially over a bumpy road.
I've not seen any decent sized RC fixed pitch coax models and all the small ones have a 45 degree lead on the flybar which stabilizes very well in still air but completely messes things up in wind or fast forward flight. My suggestion was for a single rotor fixed pitch. But make sure you get one with minimal camber on the rotor blades.
The old school Hornet I had from years ago flew well enough to explore a wide regime of flight.
And yes, they have gyros for the tail at the very least, kind of unflyable without them really. These days you can get some models with gyros for all axis's but I'm not keen on that because they always feel like it's doing the flying and not you. But you can get the small ones for around £40 that will fly indoors happily but they are a toy, fun but limited.
As for test pilots, I bet you a pound to a pinch of shit there's more than one out there who would be fascinated with what you have created thus far !! :)
Cheers for the link to Dick DeGraw's heli, I did some searching and found a brief video of it taking off, looked really smooth and very controllable !
th-cam.com/video/Q6mDK9XhklE/w-d-xo.html
And here's some more of his Jump Take Off Gyrocopters ! awesome stuff, very clever guy !
th-cam.com/video/y_COkkFuchA/w-d-xo.html
th-cam.com/video/t6xjCUVuUzg/w-d-xo.html
th-cam.com/video/0MDtdLv99WI/w-d-xo.html
th-cam.com/video/wk0AKpkaFx0/w-d-xo.html
th-cam.com/video/a882megKhVM/w-d-xo.html
Anyhow, I don't know where abouts your farm is but if it's anywhere near East Sussex I'd love to drop in for a cuppa and to see the machine in person, cheeky of me I know but design, vehicle design and specifically aircraft design has always been a favourite subject of mine but I never got beyond exploring it with RC models, another of my self taught endeavors but then flying for me is the only real magic in the world ! :)
I think we are on the same page.
The belts were sized using gates drive design software, I originally phoned them for advice but told them it was for a helicopter. At this point they ended the conversation. Hadn't thought about liability in this situation. So I went online and found their software. I'll have a look at the parameters but I'm sure it would be set at a sensible operating lifespan. The only thing is I'm now running the belts at a smaller drive pulley diameter than recommended and about to decrease this even further. I suspect this will reduce belt life. No doubt a breakage would have a catastrophic result but then there are quite a few components that can do that. The belts haven't been at the top of my list of worry's in this machine. However I had better run the numbers again and see what info I can obtain with the smaller drive pulley.
The bottom belt is wider for the simple reason that's all that was available in the double sided version, it should be stronger than the narrower one. If buying the belts again I would choose shorter ones and bring the weight down out the rear of the tilting head. That would mean less counter balance in the front needed.
The sch2a uses double sided poly v belts, much lighter set up than mine. I wouldn't mind going this route.
I can now understand the effect of wobbling weight in extended skids. Will
Definitely reduce the length but not by too much yet, gradual reduction I think will have to be the way.
Dicks jump gyros are amazing I tried to contact him via Facebook but no response yet. He must be in his 80s by now.
I'm in north Devon about 4hrs from
You ? If you're ever this way let me know.
btdixey@hotmail.com is my email.
Look at you go!
Amazing.
Reminds me of the small Helicopters from Far Cry 4. Keep up the good work, cant wait to see your channel explode when you upload the field exploration video. Where exactly are u from, somewhere down south I assume lol?
Field exploration via helo would be so cool. I hope that day comes. Yes southwest Uk North Devon.
@@Ben-Dixey Even if you don't get that far, the fact that it can fly at all is an awesome achievement!
i say increase pitch , keep rpm low..in theory it should run cooler.( or at least not run hotter
@@cd2920 good point , im thinking small plane 4 strokes with variable pitch
Bearing walk out may be symptom of drive shaft dynamics. Possibly boot distortion unbalance or even shaft bending flexure. High speed cam best way to see what's going on. Play it safe with engine rpm as its original design duty cycle might not be as demanding as a helicopter in hover. Recommend wire lock nuts to be sure that you are sure that nothing is coming loose...
google aircraft hardware suppliers to stop viscous TH-cam algorithm deleting posts about flight safety. 🙄
HOMEBUILT HELICOPTER
Weight is King.......... remember you need to aim for 1 HP per 12lbs of gross weight, so 50 HP can lift 600 lbs (12 x 50)
Keep up the good work
I remember reading that performance quote and it brings hope to the project. In the video the take off weight is 240kg that means around 44hp is being generated by the engine. quite short of the 60hp the engine is rated for but blade pitch is 6.5 degrees lower rotor and 5.5 degrees top rotor. 7 degrees I think is max lift/drag for 0012 blade, I'm confidant there is more potential in this machine.
@@Ben-Dixey 7.2 and 6.4 degrees for the lower and upper rotors sounds like a good compromise of pitch to power ratio to me :)
I Made a set of washed out rotor blades for my helicopter (6 deg twist) the performance increase was noticeable. Ps send me your contact details and we can discuss further
Hi, that sounds interesting, my email is btdixey@hotmail.com thanks
Lol, so us skinny people can enjoy pizza too 😁 2:45
Ah fair enough 😆👍
Very nice
Almost 6 1:2 minutes long yet to me it seemed like 2. I enjoyed watching your improvement on the parts AND going up little more. Cheers.