Cheap 2 seater anyone?

[David Isaac]

You get a better view at 55 knots and it is way more fun, usually any paddock will suffice as an ALA as well.

 

 

[Head in the clouds]

Alan,I've just discovered this thread. I'm researching various threads as I'm coming from a long way behind. I intend to continue with the thread until the end as I'm finding it very interesting. I would like to get involved in the project, I want my own plane and this ticks a lot of boxes.

I don't know how to PM anyone, butvI definitely want to follow the development.

 

Regards,

 

Mike

Hi Mike, this is quite an old thread and sadly the project didn't end up quite as planned but there's still a lot of good information in it from many different contributors, so if you're just starting out in the light sportplane environment it's probably worth reading through it all.

 

I did end up completing the design of the little folding biplane and then calculating the weight and balance. The balance worked out well and weight wasn't too bad considering that this was designed to be made from readily available commercial grade materials. Nonetheless I would have had to do a bit of work to try and save a bit more weight, because as it was the MZ202 engine wasn't going to provide good enough performance for safety and if we had to go to a larger engine a lot of the cost saving would be lost.

 

The death knell, though, was the cost of parts production. Early in the piece I discussed the production with a local company who have a waterjet machine that's always been under-utilised and they said they would see what they could do when the time came. In the end their quote, very reasonable though it was by Australian standards, made it unviable as a 'toy' plane, I didn't think the market would be anything like big enough to justify the time and expense because to achieve even half-way reasonable pricing for the parts would require a production run of several dozen sets at the least.

 

I made enquiries for parts to be cut overseas and the price was significantly better, about a quarter, but then the problem was materials, quite a few of the sizes weren't available and the spec was unreliable, this would mean sending material from here and back again so the double freight costs nearly doubled the price again. Even so this was still half the price of getting it done here but the catch was that minimum orders would be at least 100 parts (of each part) but the price didn't really get much better until the order was for 500-1000 of each part. As far as possible I had a commonality of parts but some were unique and others only four so it meant that even if the unique parts were cut here we would still need to plan around 150-250 kits which would require a budget way bigger than I could muster and a risk, for a toy, that I wouldn't entertain either.

 

That meant having a design which wasn't just a toy but instead had a utility purpose and the obvious one is as a workhorse on the stations. Having worked out there for several years flying both planes and helicopters I have a fair idea of what might be well received and it would be a helicopter that costs and operates at half the cost of a Cub. Unfortunately that beast doesn't exist yet so the next best thing would be a plane with half the costs of the Cub but which could operate into and out of much smaller and rougher places than a Cub can, and which has safe and predictable very slow speed handling for the occasions when it might be used for mustering. It wouldn't replace the use of helicopters by any means but could reduce the need for calling them in for many tasks with a resultant overall decrease in aviation related costs and an increase in productivity through having an aircraft available anytime instead of only when they're hired in for a muster. Top and cruise speed of this STOL aircraft would be far less important than it's low speed capabilities, however it couldn't just have huge wings like some of the early ultralights and/or hangglider towplanes because they wouldn't handle the turbulence in the heat of the day as well as something with some degree of variable geometry and lift enhancing devices.

 

There was some interesting discussion about this in the Do vortex generators really work thread.

 

With that in mind, and without bringing it to the forum I went ahead and used the construction method devised for the biplane to model up a STOL monoplane with slats, large fowler flaps, tundra wheels and long travel heavily damped landing gear quite similar to the Highlander SuperSTOL but with a novel wing-folding mechanism that allows the HS and wings to fold flat against the fuselage side in a couple of minutes and with all the controls connecting and disconnecting automatically to avoid any risk of forgetting to connect something. That came together quite quickly but before I was halfway done with just roughing it out it was quite apparent that the weight analysis was against it. Weight would be critical for something that is designed around STOL ops.

 

So I gave up the idea of a 'cheap 2 seater' because it became clear to me that the only way to achieve that is to build your own from plans if you can get them. That way it's not really cheap if you factor in your time but if you're doing it for a hobby then you only need to consider the materials cost. In which case probably the cheapest 2 seater would be built by having a good look at the free plans from Team Minimax and devising a two seater along the same construction materials/method, and power it with a Great Plains, or similar, VW engine.

 

As for mine, as I said I gave up on trying to use cheap materials and more user-friendly methods as it didn't suit the type I wanted to concentrate on next. At the end of the day if you need a lightweight but very strong airframe with built-in crashworthiness (a must for bushplanes) at moderate cost, then it's virtually impossible to beat a fabric covered, welded chromoly structure, and it 's not that much more expensive than any other method, you just have to have the tools and ability to TIG weld it. I completed the design with the 'flat against the side' folding mechanism and ordered the materials which arrived from Melbourne just before Christmas and are now waiting in a bundle on the workshop floor while I finish building a new mobile workbench/jig which should be just about done today if I go and get on with it now ...

 

I'll post a build thread once I get started and there's something to show.

 

Isn't this exactly the same thing as giving your design away? BRM Land Africa was stolen from ICP Italy on a CD, You will be freely giving your design away entirely.

No, because the intention was to spread the parts production out among a number of different manufacturers so none of them would have details of all of the parts. Additionally, on the drawings there would be no mention of what the parts were for, the drawings just show a shaped part cut from, say, 25x3 equal angle, with a number of holes in it. It has a part number, that's all. It might be a part of a camping table for all they know.

 

Well the Savannah itself is hardly an original design...Let's face it though, you can have the complete plans of most kit aircraft for a few hundred dollars anyway, if someone wants to copy it they don't have to break the bank doing so.

Yes, and even if you don't ever release plans of your aircraft, perhaps only ever selling factory built ones, there are still those who will buy one, disassemble and reverse engineer it. It's theft but nothing much can or does actually get done about it. For the charlatan it is by far the best way to go about aircraft production, they avoid all the time and cost invested in the design process and the vagaries of the marketplace too, because they just wait and watch until they see a successful product and then copy that one rather than one of the hundred or so others that aren't successful.

 

 

[ave8rr]

Hi Allan, I wondered what had happened to the cheap two seater.

 

We now know and thanks for the update.

 

We will all look forward to progress on the new project.

 

I was holding off on drinking that slab you awarded me when back in Kununurra when I came up with your wing / fuse fold design. Happy New Year

 

Mike

 

 

[robinsm]

Rob,Is your Xair foldable trailerable?

It can be but I leave it up all the time, saves time. The wings are easily removable. Check out the xair aus website for pictures of xair trailers.

 

 

[Modelmakeroz]

Hi Mike, this is quite an old thread and sadly the project didn't end up quite as planned but there's still a lot of good information in it from many different contributors, so if you're just starting out in the light sportplane environment it's probably worth reading through it all.I did end up completing the design of the little folding biplane and then calculating the weight and balance. The balance worked out well and weight wasn't too bad considering that this was designed to be made from readily available commercial grade materials. Nonetheless I would have had to do a bit of work to try and save a bit more weight, because as it was the MZ202 engine wasn't going to provide good enough performance for safety and if we had to go to a larger engine a lot of the cost saving would be lost.

 

The death knell, though, was the cost of parts production. Early in the piece I discussed the production with a local company who have a waterjet machine that's always been under-utilised and they said they would see what they could do when the time came. In the end their quote, very reasonable though it was by Australian standards, made it unviable as a 'toy' plane, I didn't think the market would be anything like big enough to justify the time and expense because to achieve even half-way reasonable pricing for the parts would require a production run of several dozen sets at the least.

 

I made enquiries for parts to be cut overseas and the price was significantly better, about a quarter, but then the problem was materials, quite a few of the sizes weren't available and the spec was unreliable, this would mean sending material from here and back again so the double freight costs nearly doubled the price again. Even so this was still half the price of getting it done here but the catch was that minimum orders would be at least 100 parts (of each part) but the price didn't really get much better until the order was for 500-1000 of each part. As far as possible I had a commonality of parts but some were unique and others only four so it meant that even if the unique parts were cut here we would still need to plan around 150-250 kits which would require a budget way bigger than I could muster and a risk, for a toy, that I wouldn't entertain either.

 

That meant having a design which wasn't just a toy but instead had a utility purpose and the obvious one is as a workhorse on the stations. Having worked out there for several years flying both planes and helicopters I have a fair idea of what might be well received and it would be a helicopter that costs and operates at half the cost of a Cub. Unfortunately that beast doesn't exist yet so the next best thing would be a plane with half the costs of the Cub but which could operate into and out of much smaller and rougher places than a Cub can, and which has safe and predictable very slow speed handling for the occasions when it might be used for mustering. It wouldn't replace the use of helicopters by any means but could reduce the need for calling them in for many tasks with a resultant overall decrease in aviation related costs and an increase in productivity through having an aircraft available anytime instead of only when they're hired in for a muster. Top and cruise speed of this STOL aircraft would be far less important than it's low speed capabilities, however it couldn't just have huge wings like some of the early ultralights and/or hangglider towplanes because they wouldn't handle the turbulence in the heat of the day as well as something with some degree of variable geometry and lift enhancing devices.

 

There was some interesting discussion about this in the Do vortex generators really work thread.

 

With that in mind, and without bringing it to the forum I went ahead and used the construction method devised for the biplane to model up a STOL monoplane with slats, large fowler flaps, tundra wheels and long travel heavily damped landing gear quite similar to the Highlander SuperSTOL but with a novel wing-folding mechanism that allows the HS and wings to fold flat against the fuselage side in a couple of minutes and with all the controls connecting and disconnecting automatically to avoid any risk of forgetting to connect something. That came together quite quickly but before I was halfway done with just roughing it out it was quite apparent that the weight analysis was against it. Weight would be critical for something that is designed around STOL ops.

 

So I gave up the idea of a 'cheap 2 seater' because it became clear to me that the only way to achieve that is to build your own from plans if you can get them. That way it's not really cheap if you factor in your time but if you're doing it for a hobby then you only need to consider the materials cost. In which case probably the cheapest 2 seater would be built by having a good look at the free plans from Team Minimax and devising a two seater along the same construction materials/method, and power it with a Great Plains, or similar, VW engine.

 

As for mine, as I said I gave up on trying to use cheap materials and more user-friendly methods as it didn't suit the type I wanted to concentrate on next. At the end of the day if you need a lightweight but very strong airframe with built-in crashworthiness (a must for bushplanes) at moderate cost, then it's virtually impossible to beat a fabric covered, welded chromoly structure, and it 's not that much more expensive than any other method, you just have to have the tools and ability to TIG weld it. I completed the design with the 'flat against the side' folding mechanism and ordered the materials which arrived from Melbourne just before Christmas and are now waiting in a bundle on the workshop floor while I finish building a new mobile workbench/jig which should be just about done today if I go and get on with it now ...

 

I'll post a build thread once I get started and there's something to show.

 

No, because the intention was to spread the parts production out among a number of different manufacturers so none of them would have details of all of the parts. Additionally, on the drawings there would be no mention of what the parts were for, the drawings just show a shaped part cut from, say, 25x3 equal angle, with a number of holes in it. It has a part number, that's all. It might be a part of a camping table for all they know.

 

Yes, and even if you don't ever release plans of your aircraft, perhaps only ever selling factory built ones, there are still those who will buy one, disassemble and reverse engineer it. It's theft but nothing much can or does actually get done about it. For the charlatan it is by far the best way to go about aircraft production, they avoid all the time and cost invested in the design process and the vagaries of the marketplace too, because they just wait and watch until they see a successful product and then copy that one rather than one of the hundred or so others that aren't successful.

Thanks for tbe comprehensive reply Alan,

 

Chrome moly traditional frame would interest me. Welding isn't new to me, but fabric covering would be a new experience.

 

I like the idea of STOL and it was seeing the 7 day wonder (a CH750) going together at Oshkosh this year that set the hook.

 

I have been taking lessons at the local GA school and have recently tried to get lessons with a local RAA instructor but no joy so far (he has a Savannah).

 

I've looked at the X-air aircraft that robinsm suggested and made an enquiry to the dealer.

 

I've spent a lot of time researching and I still know nothing (even less than Sgt Schultz).

 

Regards,

 

Mike

 

 

[Modelmakeroz]

It can be but I leave it up all the time, saves time. The wings are easily removable. Check out the xair aus website for pictures of xair trailers.

Thanks,

I've posted an enquiry and will go back and look at trailers.

 

I earlier made some enquiries about Gazelles for sale and thought "an awful lot of money for worn out GA trainers no longer being LAME inspected".

 

How did you arrange your training? The 25 hours bizzo if I kit build would just about snooker me as I'd need to pay someone to fly them off then I could take a trainer on board, from how I read the regs anyway.

 

Regards,

 

Mike.

 

 

[jetboy]

Mike,

 

just reading this thread for first time - there is some discussion of similar nature here at moment

 

http://www.recreationalflying.com/threads/zenith-ch-701-thread.5964/page-21

 

The 701 does have plans with the option of folding wings, not easy because a fair amount of defuelling is needed and most people - even with Avid Flyers and kitfox types which are super easy to fold / unfold - usually dont bother to fold. I think the trailerable / folding wing aspect is something thats attractive to have until you get setup with a home base - which can be as simple as a polyester tarp over pipe arches type shed (which I built for about same cost as the 701 folding option would have) not forgetting that if one is prepared to remove seatcovers etc. after flight and regularly wash any grime off then models like Savannah and Zenair are OK parked outside.

 

Ralph

 

 

[paulh]

HITC is this aircraft along the lines you are thinking

 

 

 

 

[David Isaac]

HITC is this aircraft along the lines you are thinking[ATTACH=full]33412[/ATTACH]

No that is just a modified Piper Cub with no clothes on.

 

 

[Keenaviator]

Probably on the high side of 100k too so not really 'cheap'.

 

 

[dazza 38]

The new Zlin Savage Agilis is a cheap two seater.

 

 

[bexrbetter]

The new Zlin Savage Agilis is a cheap two seater.

??? ... Shirley ......

 

http://www.mcp.com.au/cub/price-list/Zlin%20Price%20List%202015.pdf

 

 

[dazza 38]

??? ... Shirley ......http://www.mcp.com.au/cub/price-list/Zlin Price List 2015.pdf

Well cheap when compared to other new two seaters.

 

 

[bexrbetter]

Well "cheap" when compared to other new two seaters.

"Less expensive" comes to mind.