Affordable helicopter?

Hoss-Fly

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Joined
Nov 8, 2003
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Howdy all,<br>I've been keeping an eye on the kit helicopter market for a long time.  Either I'm a cheap SOB or do you all think that the current line up of kits available are far too expensive for what they are?<br><br>Anyone got an update on A/W-95?<br><br>Fly Army,<br><br>Vince Rodgers<br>
 
Re: Affordable helicopter?

If you can handle a single place, what's wrong with the HELICYCLE?
 
Re: Affordable helicopter?

Hoss-Fly-<br><br>I have been thinking about a cheap helicopter in comparsion to others.<br><br>You need to get rid of the expensive transmission and the power absorbing tail rotor.<br><br>Lets try this by mounting the engine (2cylinder horziontal)  mounted on bottom of the mast with a ducted four blade Propeller(fan) on propeller shaft.  The propeller and hub should weigh the same as the engine to cancel gyroscopic forces.  This would do away with clutch, free wheeling clutch, cooling fan,tail rotor and its drive.   The fuel tank  feed could be thru slip rings on mast.  You would get lift from rotor and propeller. ::)<br><br>I plan on building an RC model of this configuration as an experiment.<br>Randy Brooks
 
Re:Affordable helicopter?

Randy,

This may be an old topic but let's see if we can generate some more interest in this. I have been looking for an affordable and safe single place heli design. There is an abundance of junk out there. Since momma didn't raise any dummies, they won't be getting any of my money. I'm convinced there are ways of building with economy and safety if you're willing to put in the time to shop around. Starting with a good design, do you know of any? The A/W-95 looks reasonable but I can't get a reply from Vortech on design options such as pre-fabbed blades. Have you found anything since the first post?
 
Re:Affordable helicopter?

Tom:
No I have not found any thing after the orginal post. Rotorway looks the best of any. Very expensive. There are a few of the older Scorpions available in the 12 to 20,000 bracket.

Randy :eek:
 
Re:Affordable helicopter?

Does anyone know of the mini-1 copter?

On the A/W 95, it looks like some in the PRA tout it as the only real UL heli plan. Somewhere I heard it used home made blades, not something I want to stake my life on. Has anyone actually bought a set of plans? I'm curious as to the detail. For the price I would expect some decent documentation.

Finally, in spite of all the advertisement and talk, I have yet to hear from anyone that has actually built a heli from plans. Kits seem to be another story but, like you say, the price is enough to kill enthusiasm. ;)
 
Re:Affordable helicopter?

I am convinced that a two-place heli could be built for the same price as the price of a two place gyro; but i you are interested in one seat heli, the a/w 95 is a good choice...
 
Re:Affordable helicopter?

Why are helos so expensive? Cause they have so many parts.
Flight controls, transmitions, extra parts, all add up to make them one expensive way to get around, but a very fun way.
I would have to differ with quadrirotor on the statement the you could build one for the same price as a gyro, as the differences are quite marked.
One thing that seems to make the price higher is the cost of certified machines. Anything certified will start at $350,00AUD, and go up from there. Im not sure of the kit prices, but the only one available in Aus seems to be the exec.
THere is a cheap one $30,000US found herehttp://www.innovatortech.ca/index.htm.
One thing that troubles me personally is the flying qualities of the kit helos available. The only two I would even consider palcing my but in would be the Helicycle, and the Rotor mouse.
Everything else I have seen have serious design issues, from power limitations, bad drive train design, or improper balacing. Any helo that requires a balast weight to bring the helo within CG limits, in my opinion was not properly designed.
This is one of the reasons I have set out to design my own. I have purposely made it different in a number of areas, which should make it safer than many certified helos.
Will my design end up cheaper than whats around now, only time will tell. One thing that will be in my foavour is the Aussie dollar being weaker than most of the currencies, may help to keep the cost down.
ANyway thats the end of my rant.
I must say its great to find a forum where homebuilt helos are discussed. So far its the only one Ive been able to find.
 
Re:Affordable helicopter?

I agree with you, spaced, the price of a machine is directly linked to the number of parts, complexity of the parts, price of exotic materials and the quota of the R&D involved in the design.
The number of parts in the Safari is not really bigger or more complex than the one of the RAF2000...The biggest part of the cost is the R&D for a commercial product and the number of AV-certified parts.

it's actually very interesting to have someone building an heli and posting on this forum: can you give more info on your design, why is it so special, may be you could have free advices... :) ???

http://www.lafhelicopters.com/
 
Re:Affordable helicopter?

I cant comment on the complexity of the RAF2000, but I imagine for one that the control system would be more complex.
Another factor with helos is the nature of the gearbox. With a Gyro you can have a realatively simple PSRU, while a helo has to have a step down for the MR, and a 90deg drive for the TR (asuming it has one). A helo also requires a free wheeling clutch, so it can auto if required.
Every time a "cheap helo" comes onto the market a spate of accidents seem to follow. Remember the mini 500? Alot of people died while that got sorted out. This isnt just reseved for experimental helos though, early on a R22 was the most dangerous thing trying to stay in the air. The A-Star early on was known as the Death star, or falling star, and Bells having its fair share of probs with the 407.
Helos are so complex, from the aero, to the maufacture, there are so many variables.
One only has to look at the progress made over the last 50 years, while the Wright Brothers would have troulbe believing a 747, or a long ease, Igor Sikorsky would have no trouble understanding a modern helo.
Some aspects of my helo Im happy to talk about, other aspects I may have case for patents, so if discussed I will be unable to patent the idea.
In general, I believe that the helos traditional layouts is one of its down falls. The TR absorbs power from the MR (upto 15%). Ontop of that most helos are built with rediculously low margins on TR authority. This can lead to a loss of tail rotor effectiveness (LTE), and has caused fatalities over the years. Another problem is with the MR chopping off the tail boom. While a helo can be controlled in flight without a TR, the change in CG can cause a nose down crash.
Basically my helo is a Co-axial layout (counter rotating blades ontop of each other ). For one this gives the advantage of neutral hadeling when power is applied. The cancelation of torque by the rotors means that the helicopter is more stable, and predictable and easier to fly.
Antother thing Im looking at is adding a ducted fan to the rear to add thrust in forward flight offloading the main rotor.
I havent finished the calcs yet, but I believe that by having the blades auto roating in forward flight, should increase the blade life.
My goal is to produce an experimental high speed helo. The goal is a cruise of around 150knts. Its pretty ambitious, but so far I havent hit any major snags.
I could add more but im getting sick of typing, any questions just ask.
quadrirotor, are you involved with the laf helicopters?
 
Re:Affordable helicopter?

Yeh Ive seen both of those.
Dave is the man behind the unicopter and a regular at one of the sites I visit. I like the concept, and he has a lot of good ideas. His site is a wealth of information. I hope he can get one built.
The Maryland project was very interesting, I stumbled across that a while ago while I was doing some research.
It is a very thorough report, and learnt alot from it. Shame its only a study and more than likely will never fly.
While Im a big fan of the synchro copter layout, I beleive it has one major draw back, ground clearance for the rotor tips.
While in the air it has a lot of advantages, on the ground its more dangerous than the traditional MR TR layout.
If you have ever seen a K-Max on the ground you will know what I mean. The mast is nearly 4m off the ground, and with the rotors running, on flat ground, you still wouldnt be able to approach from the side.
Early on this was my preferred layout, after moving on from a side by side layout. Unfortuately I couldnt find a way to make it safe on the ground.
This is why I moved to the coax layout. I feel this has the most to offer while being the safest on the ground.
 
Re:Affordable helicopter?

The coax heli has some drawbacks too!... In autorotation you must inverse the inputs in the commands!...High speed is tricky!... the head is awfully complex etc...too complex to be reliable enough for homebuilt heli. why don't you try a safari alike heli (with tandem seating and subaru engine etc...)?

http://www.airscooter.com/
 

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Re:Affordable helicopter?

I am also very much for a coax solution.

Does anybody know what happend to the Nolan Bros
Eagle's Perch Heli. The web site was always very scarse,
and no news about it since some time.

It looks like the idea has been revived in AirScooter.

http://www.airscooter.com/

The solution is simple gimbal rotorhead, not so complex, no swashplates.
Almost as simple as gyro controls, but how (and if) it works...?

I think the similar solution was used on Sikorsky S-69 (XH59A) ABC.

Anybody has any news about such helis?

PTKay
 
Re:Affordable helicopter?

quadrirotor, yes the coax is more complex in some areas, and simpler in others.
The Synchro copter suffers from the same problem with control reversal in autorotation also. With the K-Max and the Huskie, the pilot is required to apply opposite pedal, in the Kamov helicopters, the controls reverse themselves in auto.
The synchro copter has some disavantages in yaw over the coax. The synchro copter acheives yaw through differential longitudinal cyclic (with a small amount of diff collective). Due to the position of the disks being very close, and the fuselage limiting the amount of travel available, the yaw control is a little mushy. This is especially true in an auto.
The coax layout acheives yaw through diff collective which under power is much more effective.
Most of the objections I have heard and read about the coax layout, for me havent held alot of water. While they are there, most of them I have been able to over come (atleast theoretically).
I have designed a new layout for the gear box, and a better method for yaw control (actually the yaw control is an old idea Ive revamped).
Unfortuantely not being a real engineer Ill have to pay some one to do the final design and spec on the gear box, but the people Ive spoken with have seen no problem so far.
I should mention that Im not really looking to put out a budget heli. Im looking at a high speed VTOL ship with a high degree of built in safety, on ground and in the air.
While I personally enjoy the challenges of flying a MR TR helo, There are alot of people, who wont have the coordination requred to enjoy it.
My goal is to have a ship which is easy to fly and stable, with a small HV curve and good redundancy. While Im sure this is the goal of most designers, I see very few who are actively pursuing this goal.
Most designers seem content with the MR TR layout, and leave it at that, and get the best from there. THis is one of the reasons I have chosen the different layout.
THere have been a number of inovative designs over the years, which had they seen fruition, we would be looking at a different helo market today.
Its a shame that the experimental helo market hasnt yet flourished in the same way the experimental fixed wing market has. Designs like the Mini 500, seem to have kept people away from the market. And really who can blame them, as yet, the only design I would trust my life to would be the heli cycle.
It always surprises me what people are prepared to put up with in aircraft, things they would never put op with in a car. Little things like the placement of switches, through to bad flight characteristics in certain areas, LTE springs to mind.
Whether my design will ever see the light of day, Im not sure, Im just about ready to start building my first scale prototype, so hope fully Ill star to get some idea of flight characteristis soon.
<end rant>


PTKay, Im not a big fan of the airscooter for a couple of reasons. THe first being there is no collective pitch control. Rotor thrust is controlled via throttle to fixed pitch blades. This means the aircraft is limited to 50ft AGL, other wise engine out landing becomes impossible.
While the gimble Idea offers simplicity, its only practical for light helos. AFAIK some early helos used this system, but even for something as light as a R22 the control loads become very high.THis is why nearly every helo uses the cyclic control for pitch and roll.
The S-69 didnt use a gimbal system. It used a cyclic system, on ridgid rotor blades. A ridgid blade has no flap, or lead/lag hinges, only feathering. There are a few helos with this set up, some of these are the BK117, Bo105,and Lynx.
THe ABC was aimed at 2 different military contracts, however they decided thye wanted a tilt rotor instead. The 2 aircraft are in storage, however some critical components have exceeded their time, so more than likely they wont fly again.
The unicopter site has some good info on it, under the ABC section. (theres a link posted by quadrirotor a couple of posts up).
 
Re:coax layout?

Re:coax layout?

Can we have some kind a device which could lower, automatically, the pitch of the blades if there is no torque on the power mast (for autorotation purpose and simpler tilted rotor head)?
 

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Re:Affordable helicopter?

I have had the same idea to overcome the shortages of the
AirScooter. Such device to create collective pitch in reaction
to engine power shouldn't be too complicated.

Regarding the high forces on gimbal rotor, I think the
Eagle's Perch used hydraulic conrols to solve the problem.

BTW, again, does anybody know what happened
to this project.

The other interesting coax solution was (is) the Gyrodyne.

PTKay
 
Re:Affordable helicopter?

Eagel's Perch
 

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Another Eagle's Perch
 

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Re:eagle perch?

I think they left the homebuilt market to make RPV and SAH (remotely piloted vehicules and small autonomous helicopter) for the army!...They use the same concept to make small helicopters (spy, target, weapon...)
 

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