Collaborative Design Challenge – Working Together to Create a Plans-Built Design

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Nims11

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A The Dyn'Aero MCR01 or a Diamond DA20 are both good marks to hit. To get the same specs for $30k per member would be a reasonable goal. With good design and scrounging it can be done. Think about coordinating with people that currently have molds for wing skins, canopies, cowls, etc... and start working deals for a set of parts and design and build the rest. Get out of the box on how to make parts and molds for cheap for a few or a dozen sets of parts and solve those problems and then start filling in the blanks. All doable.
About 850cc dry sump twin water cooled with a turbo and EFI would be a nice little engine. About 100HP at FL10 would be nice. A belt drive PSRU or a Rotax B box would work.

How much do you think that would set you back and how much do you think it would weigh?
I like the MCR01, maybe that could be the target but balance it out a bit with aspects of the DA20, and Autoreply pointed out the Europa, also a nice plane. So we could use as models the MCR01, DA20, Europa, and also at the end of the spectrum the CTSW. The MCR01 is impressive in that it cruises at 170mph (the earlier figure was incorrect) on 80HP. But it is probably cramped in the cockpit, and maybe could be tones down a bit, increase wing area a little, but we could increase the HP to compensate to 100hp. That is what I feel is a good target. Of the 4 planes listed 100hp is about the mean. So, I feel a carbon fiber airframe with 100hp engine is a good target and borrowing heavily from the MCR01 design.

As for the engine, I was reading through the auto conversion forum and came across a thread that talked about turbocharging an engine at a lower rpm. Think about this for a second. Take the Hyundai 1.6 Ltr Gamma engine just as an example of what's out there. 138HP at 6300rpm and weighing about 210 LBS, a little heavier than a rotax 100hp but not much. If we derate it to 100hp what rpm would that be? I could not find a dyno on the engine so...a guess might be at 5000rpm (or maybe 4500). What rpm are we shooting for? The Aerovee is 3400rpm, the guy who had the very successful Long EZ conversion with an LS1 engine had in direct drive at 3500rpm. Catto props made a 3-blade prop for this engine that they still sell. Maybe 3500rpm would be a good target, it is not too low that we would have to over boost the engine. We would give up some prop efficiency but maybe make it up by increasing HP to 105.

So, we find an auto engine with good characteristics for boosting, match it with a good turbocharger, and boost it at 3500rpm to get to 105HP. This with an emphasis on avoiding detonation and torsional vibration. And this solution would avoid the complexity of a PSRU.
 

BJC

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Warning!!! Long wordy post ahead!


As the title says this thread is an attempt to launch group collaboration on an airplane design of a specific type.

I am absolutely certain this could be a successful and rewarded project.

The principles that must be adhered to for the collaboration aspect to work are as follows.

1. Participants must be willing and able to compromise, and thereby go beyond their individual egos for the greater good of the project.
2. Participants must be motivated and committed to this project for one of two reasons.
3. There must be an orientation and disposition relative to all design problems as solutions that need to be discovered.
4. There must an emphasis and discipline on continuously moving forward, and completing the project in a timely manner.
5. Lastly, I feel there needs to be one to three leaders of the core group.

1. All composite structure
2. Conventional design 2-place
3. Low build time
4. Cost under 30K
5. High efficiency
6. Comfort
7. Excellent stability and safety

This forum is a good place to introduce it but to actually get any real work done it would be best to move it to a website created for the project.

As stated previously there needs to be a core group, or leadership team, however you want to call it, which will act to make final decisions about how the design will evolve.

To bring does cost and time, not only will the design be a collaboration but the build itself could be a collaboration also.

For the engine and prop of this design, which is the single biggest expense, I was thinking that we could build into the design the allowance for 3 options, the VW Aerovee type at 80hp, the 100hp Rotax, or the Jabiru or rotax 120HP.

This is getting to be an overlong post, and I’m not sure if there will be any interest at all. So I'll stop here and see if there is any feedback.

As you said:

This forum is a good place to introduce it but to actually get any real work done it would be best to move it to a website created for the project.
It is time to stop talking and act.


BJC
 

etard

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Seems people need a bit of competition to get the creative juices flowing. I think some sort of X prize Sponsored by the EAA or similar organization would help keep group members on task.

Also, a good way to keep each member accountable for fulfilling their part of the deal could be for each member to invest $10k in the project and if they became a problem, they could be voted out of the group and lose their buy-in.

I don't think anybody is freeloading here, I don't even know where that idea came from. The idea is to pool talent so that guys that are good at designing aren't wasting their resources learning how to weld, and vice-versa.

I am on a model engine building forum and they have group builds all the time, each member is assigned a certain amount of parts to machine and then the finished parts get mailed out to each member and each person has a completed kit that they only need to assemble. Most of those guys are retired, so they have that to their advantage.

I would totally be on board for a project like this. It could also be setup so that a build session could be planned at a location where all group members could come and help make the molds during a week or two.
 

autoreply

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I appreciate that your comments are in the spirit of pointing out potential pitfalls. But it is not simply that I think your being negative, some of your comments are gross exaggerations. Like when you said in order to copy a DA20 you would have to buy one and tear it apart. Or in this resent post where you went on about how we have to account for employ cost, sick leave, insurance, business license, marketing and advert, , bookkeeping, tax prep, legal service, cleaning service, blah, blah ,blah. We're talking about individual guys working on a homebuilt out of their garages, and collaborating remotely. Where is the employee sick leave and marketing fees in that? Even having to respond to this is tiring and counter productive. I sense that you are genuinely trying to be helpful but... I can't see it as anything but an exaggeration, or worse irrelevant.
Frankly, Topaz mihht be a bit optimistic in his post. We're talking on the order of 10-20K manhours. And yes, really, all those factors do come into play. We're talking about a decade full time...
 

Jay Kempf

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Frankly, Topaz mihht be a bit optimistic in his post. We're talking on the order of 10-20K manhours. And yes, really, all those factors do come into play. We're talking about a decade full time...
Wow, you guys are way out in left field. Time to reign you back in.

Leon Davis built several all metal planes from a notebook with a scientific calculator with only plywood forms in a few years each, solo. He was by self admission dyslexic. Never used a computer. Even pioneered a Briggs and Stratton motor installation with a hand made prop towards the end of his life in a completely new design.

You guys are talking about a commercially funded large development program and then extrapolating into profits that need to be made. Sheesh. Back to earth. This ain't Boeing. People with simple shops and limited funds can build airplanes. Or are you saying they can't? Or shouldn't?
 

autoreply

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They sure can. But even with the needed experience we're talking 5000 hours plus in engineering and building for such a design (not the da11).

Throw aside the romanticism and I've yet to hear of the first project that does better...
 

Jay Kempf

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They sure can. But even with the needed experience we're talking 5000 hours plus in engineering and building for such a design (not the da11).

Throw aside the romanticism and I've yet to hear of the first project that does better...
5000 hours is a year and a quarter of business days without distractions. That is certainly adequate to design an airplane. It may not be adequate for Boeing to design a complex airplane but it is adequate to design and airplane. It might not be adequate to bring a novel new airplane concept and the associated company to full scale production but it is adequate to design an airplane. This thread was an assumption that a group of people would come together and divide tasks to get to a goal. Say six people came together. That's six people over your 5000 hours. Seems a lot of resources. Not everyone needs to be doing the engineering. Lots of apples and oranges going on here.

Can we just get out of the whole production, corporate idiom? Seems inappropriate to the discussion. I am completely conversant in how conservative production engineering is perpetrated. Drives me nuts doing things by committee. There is no romanticism. Tasks, resources, cash available, what can be done? Six people coming together to build a single design has to have advantages over a single person taking on the task.
 

autoreply

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5000 hours is a good number for people who've designed, engineered, built and tested aircraft before. Without real world experience it's a multiple of that...

84 hours a week is delusional. 20 is more realistic without job obligations. Cleaning, arranging Parts, searching materials and suppliers etc all too require time.

Disagree... everyone is welcome to but I've yet to see the first person who has DONE it better and not just talked about doing it better...
 

Riggerrob

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5000 hours is a good number for people who've designed, engineered, built and tested aircraft before. Without real world experience it's a multiple of that...

84 hours a week is delusional. 20 is more realistic without job obligations. Cleaning, arranging Parts, searching materials and suppliers etc all too require time.

Disagree... everyone is welcome to but I've yet to see the first person who has DONE it better and not just talked about doing it better...
............................................................................................

84 hours a week is do-able with a team of amateurs. That means an hour or two per evening and one full
day on the weekend.
With the inter web, guys could review each other's work much quicker and confirm that is still compatible with their component.
I am envisioning a group based on the OP's parameters. They sign a basic "play nice" agreement and toss some dollars in the pot. At the first meeting, they agree on basic bulkhead sizes, then the engine guy goes off to work on firewall forward. Meanwhile the cockpit guy starts drawing seat dimensions, the wing guy starts putting numbers on his sketches, etc.
At their second meeting, they review each other's calculations to confirm compatibility.
By the third or fourth meeting they have agreed enough to rough-out a mock-up and bolt it together.
By the fifth meeting, the engine guy takes home a mock-up firewall, while the fuselage guy goes home with a mock-up engine mount and throttle cable.
They continue trading drawings, mock-ups, sample components, etc.
A second set of eyeballs is the best inspection tool.

When they run out of ideas, they drool over news of the shiny, new Glasair LSA, which made its first flight this week.
 

BoKu

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5000 hours is a good number for people who've designed, engineered, built and tested aircraft before. Without real world experience it's a multiple of that...

84 hours a week is delusional. 20 is more realistic without job obligations. Cleaning, arranging Parts, searching materials and suppliers etc all too require time.

Disagree... everyone is welcome to but I've yet to see the first person who has DONE it better and not just talked about doing it better...
What Jarno said. I been to this rodeo before, and I can tell you it is a meatgrinder. Them as done it are the ones you want to help, but few if any will go back for free.

Thanks, Bob K.
 

Nims11

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All this back and forth bickering... what a waste of time. Why bother. My mistake for even responding to Topaz, I should have just let it go.

If you don't have anything constructive to contribute why try and drag the whole thread down into the mud.

I put down an idea (actually not my own) of a way to reduce the heavy cost of the engine, by doing an auto conversion with a turbocharge. Instead of responding to that in some way, even telling me it is a stupid idea AND why, the response I get is that for this project to work you really need employees, legal services, and a cleaning lady. Unbelievable!

Autoreply, if you want to contribute something constructive, please be so kind and respond to my turbocharged auto conversion idea, and tell me why it won't work. Thanks.
 

NoStealth

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So Nims, have you joined Makerplane yet? and why not?

There seems to be some recent Makerplane activity. Maybe you, Jay and RiggerRob can start another higher performance Dynaero like design with them.
The makerplane group build idea included group or garage business production of fast build parts like the RV and Rutan designs.
Always remember that there are people that will happily take your free engineering, design and testing work.

Nims, You are just starting your flying-building adventure. Take a look at Boku's journey. Do you want to build or fly?
Finish your license, go to flyins, hang around the airport, fly other planes, find local homebuilders, join EAA, akaflieg, ESA, Makerplane, help an AME wrench. Learn.
Your mission will change with time, family..

And there are always lots of incomplete projects and flying planes in your price target, or do you have a touch of keeping up with the jetsons fast glass-itis?
 

NoStealth

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It will. There are several types of blue foam though. One has a polyester skin on each side which is not going to work for anything. The pink fanfold is OK but it varies in thickness quite a bit so you have to spend some time piecing good pieces together, not a big deal. We tested the configuration making a VERY light and VERY stiff kayak. Worked great. You can do one off or you can laminate ahead of time and piece the long flat planks together after. Vac layup on glass saves a lot of sanding and finishing on the order of 90% of the fumes, mess, sanding, finishing. The kayak was 17.5' long.
Don't leave us hangin' what did it weigh? pics and details pretty please :)
 

Nims11

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So Nims, have you joined Makerplane yet? and why not?
No, but I'm definitely going to do that asap.

There seems to be some recent Makerplane activity. Maybe you, Jay and RiggerRob can start another higher performance Dynaero like design with them.
The makerplane group build idea included group or garage business production of fast build parts like the RV and Rutan designs.
Always remember that there are people that will happily take your free engineering, design and testing work.

Nims, You are just starting your flying-building adventure. Take a look at Boku's journey. Do you want to build or fly?
A bit of both.

Finish your license, go to flyins, hang around the airport, fly other planes, find local homebuilders, join EAA, akaflieg, ESA, Makerplane, help an AME wrench. Learn.
Your mission will change with time, family..
All good advice. Thanks for you input.
 

Riggerrob

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.....

When they run out of ideas, they drool over news of the shiny, new Glasair LSA, which made its first flight this week.[/QUOTE]
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From a distance the new Glasair LSA resembles a Glastar with high wing, tri-gear, etc. but differs in construction methods. When the first Glastar was built in 1994, it combined a variety of construction methods: sheet aluminum horizontal surfaces. composite fin and fuselage shell wrapped around a steel tube cockpit roll cage.
Now the new Glasair LSA has an all composite airframe. They say that an all composite airframe is less expensive to build these days. What have they learned about composite construction over the last 20 years?
 

Pops

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Don't leave us hangin' what did it weigh? pics and details pretty please :)
Back in the 80's, I built a 17' long composite 2 person kayak. Very strong and the weight was 25 lbs.

Dan
 
S

SvingenB

Less expensive than what?
Exactly. Glasair is a factory producing factory airplanes pretending to be homebuilt. It takes 2 weeks to "build" a Glasair. This is as far from planes built as it is possible to get without purchasing new aircraft. A glasair is not cheap either, That LSA it will probably cost more than a homebuilt RV-12, and they typically cost US$ 90k. With this in mind, it is not that far to a Diamond DA20 that is a real aircraft, not some LSA.
 
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