Why aren't there new plans-built designs?


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Well-Known Member
Aug 30, 2006
St. Louis, MO, USA
A recent post caused me to stumble onto this FAQ (clumsiliy anonymized so that nobody thinks I'm trying to attack the designer):
Q1: Are plans available?
A1: There are no plans for sale, and we cannot offer plans for sale in the future. There are several reasons for this. First, plans would require a lot of time and effort to draw and we are still working at our day jobs. Drawing the plans would not be worthwhile for us because in today's market, selling plans is a money-losing proposition. You can't charge very much per plan set, and many builders expect the same level of support as if they had baught a full kit. The phone bill alone is enough to more than you can charge for the plans. Second, many designers have had their designs "borrowed" by unscrupulous people, who either copy the plans for their own use, or make slight modifications and sell them as their own. We've already had this happen on another project. Finally, it would be too easy for people to make modifications which might lower the margins of safety we have designed in. There is a definite possibility that we will offer kits, if the test program convinces us that the airplane performs well, and if enough people express interest. Drop us a line if you would like to vote for a kit version.

I have to admit that the answer bugged me. So I'm curious to see if the opinions from his answer are reflected in the community here. If so, it would explain why most designs are sold as kits and no plans are available for any price. Again, I'm not trying to beat up on any particular designer/company - I'm just trying to get some insight...

Here's what bugged me:
If design support is an issue, why not take some cues from the IT world: provide FAQs and/or access to product-specific forums for free, then charge $50 / hr for support. Or better yet, charge $1,000 - $2,000 for a set of plans instead of $200-$500. I'd certainly buy a $2000 set of plans if I liked the design and felt that the plans were detailed enough.

Yes, design stealing is a problem, but I don't see how only selling kits really solves that problem. It's not like you can't reverse-engineer a kit or even a certified airframe. Yes, it's harder to do the reverse-engineering than just copying some plans, but if the kit is popular enough and stealing doesn't bug you then I can't see how skipping the engineering work for a "simple" mod is going to bother you either.

"Finally, it would be too easy for people to make modifications which might lower the margins of safety we have designed in." :ermm: Again, how does selling only kits address this concern? Granted, the guy who might have bought hardware-store bolts instead of AN hardware now has AN hardware in his kit... so maybe he uses what came in the kit... or maybe he loses the bolts from the kit and uses a hardware-store bolts anyway. But a kit doesn't provide any barrier for someone who wants to add a "bigger engine" or "clip the wing for speed."



There are a few plans only airplanes available, Sonex comes to mind, but none I can think of that appeal to my tastes. In fact, I inherited a Sonex formed aluminum kit and plans from my brother when he passed away, but I just don’t like the looks and cramped cockpit. So, I’m one of those guys that’s borrowing some stuff from Sonex, namely the flying surfaces. I’m simply designing around the formed aluminum kit. I’ve kicked around the idea of offering plans on this forum and was quickly scolded by the guys who know aero engineering. I can still see it happening if I could get 50 or so folks to kick in $100 it might get some analysis time from one of them and then we could all build one. ;)

Here’s my single place version.


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