A path to an affordable trainer?

On Thursday, August 1, 2013 9:58:40 AM UTC-7, Roberto Waltman wrote:


Could be slightly higher with a more streamlined front, (without

engine and prop.)

Of course, it would need a large dead weight in the nose to keep the

CG between limits.

Isn't that what the student is for?

Kirk
66

The xenos was going to bemy 'next' project. 1-26 performance in a self launcher youget to build yourself! What could be more fun?
On Wednesday, July 31, 2013 2:23:46 PM UTC-7, WB wrote:
See: http://makerplane.org/ Just ran across this crowd-sourced campaign to design and build an open-source airplane. They are shooting for $15,000 US including engine. I think they could make the airframe for $15k. I have my doubts about a safe, reliable powerplant AND airframe for anything near $30,000. I would dearly love to be proven wrong. The website is worrisomely short on details, but the overall design doesn't look far-fetched (no twin boom, pusher, three lifting surface homebuilt F-22 fantasy). They propose a conventional looking plane built of foam-cored composite panels cut out with CNC mills and non-structural stuff made with 3d printing. A similar concept, flat-panel, pre-fab composite version of a K-18 was make by a Brit once upon a time and looked pretty good. Don't know what became of it. If Maker Plane can make this work at even twice their projected cost, could the same method be used to produce a reasonably priced training glider? Even $25,000 for a new, two-seat trainer in the 28:1 neighborhood would be a fantastic bargain these days. Certification is a glaring issue for a glider destined for commercial training. However, if the glider only cost $25,000, it would be cheap enough to be viable in the non-commercial club market where an experimental cert. would be OK.

On Thursday, August 1, 2013 9:33:12 AM UTC-6, Bob Kuykendall wrote:
The big issue with a kit is that it is difficult to type-certify it. An experimental two-seater has very much less utility than a type certificated one that can be used for rides, sightseeing, demos, flight instruction, transition training, and other commercial purposes.



Furthermore, the type of wing construction used in the RVs does not scale very well up to the kinds of spans and aspect ratios required to make a glider that is worth building. When Dick was building a motorglider, he used wings from an HP-18. When I was deciding whether and how to move beyond the HP-18 and build kit sailplane wings, I settled on a Marske-style wing spar and European-style molded sandwich skins. No, not many people can do that in their garage. But it's not rocket science, and it has proven to be the most time- and cost-effective path to a set of glider wings worth having.



I'd be perfectly willing to work with clubs and even commercial operations on a sweat-equity basis. Given the right tooling and infrastructure, making sailplanes is not that hard, and I can get pretty much anybody doing it in just a couple of hours. I'm doing that today, in fact, up at the HP-24 Project 2013 Summer Akaflieg. The next Akaflieg is scheduled for the week between Christmas and New Years. If there's enough interest we can start laying out CNC cut parts for Aurora's big shells.



Thanks, Bob K.

https://www.facebook.com/pages/HP-24...t/200931354951

No dig at commercial operators as they are generally available more often than clubs, weather permitting. However, there may be about commercial entities using gliders in the US. AFAIK, there are two university academic gliding programs. There are about 144 clubs/chapters with public access and another 25 that are strictly private. There are about 6000 SSA members in chapters, and several hundred more in clubs that are not chapters, perhaps 1000 or more. Although a type-certificated trainer/ride gliders would seem more desirable from a designer/developer stand point, there are type certificated designs that aren't in production. The bigger hurdles and costs are establishing Part Manufacturing Authorization and Manufacturing Certification. Need an example? Peregrine Sailplanes. If it were easy, I think 2-32's might be in production today. Of course FAA restriction of allowing development of a design as experimental or SLSA and later granting a TC for the same design is a real problem and impediment to innovation. Perhaps some of the alphabet aviation organizations and their memberships would consider suggesting to the House and Senate General Aviation Caucuses that a change is needed. The House caucus just reached 200 members. Earl Lawrence (formerly of the EAA) now heads the small aircraft directorate. Perhaps there's a receptive ear there.

I'm not sure this goes far enough to help the gliding community.

http://www.kansas.com/2013/07/16/289...alization.html

Frank Whiteley

On Saturday, August 3, 2013 9:42:22 AM UTC-6, Frank Whiteley wrote:
On Thursday, August 1, 2013 9:33:12 AM UTC-6, Bob Kuykendall wrote:

The big issue with a kit is that it is difficult to type-certify it. An experimental two-seater has very much less utility than a type certificated one that can be used for rides, sightseeing, demos, flight instruction, transition training, and other commercial purposes.







Furthermore, the type of wing construction used in the RVs does not scale very well up to the kinds of spans and aspect ratios required to make a glider that is worth building. When Dick was building a motorglider, he used wings from an HP-18. When I was deciding whether and how to move beyond the HP-18 and build kit sailplane wings, I settled on a Marske-style wing spar and European-style molded sandwich skins. No, not many people can do that in their garage. But it's not rocket science, and it has proven to be the most time- and cost-effective path to a set of glider wings worth having.







I'd be perfectly willing to work with clubs and even commercial operations on a sweat-equity basis. Given the right tooling and infrastructure, making sailplanes is not that hard, and I can get pretty much anybody doing it in just a couple of hours. I'm doing that today, in fact, up at the HP-24 Project 2013 Summer Akaflieg. The next Akaflieg is scheduled for the week between Christmas and New Years. If there's enough interest we can start laying out CNC cut parts for Aurora's big shells.







Thanks, Bob K.



https://www.facebook.com/pages/HP-24...t/200931354951



No dig at commercial operators as they are generally available more often than clubs, weather permitting. However, there may be about commercial entities using gliders in the US. AFAIK, there are two university academic gliding programs. There are about 144 clubs/chapters with public access and another 25 that are strictly private. There are about 6000 SSA members in chapters, and several hundred more in clubs that are not chapters, perhaps 1000 or more. Although a type-certificated trainer/ride gliders would seem more desirable from a designer/developer stand point, there are type certificated designs that aren't in production. The bigger hurdles and costs are establishing Part Manufacturing Authorization and Manufacturing Certification. Need an example? Peregrine Sailplanes. If it were easy, I think 2-32's might be in production today. Of course FAA restriction of allowing development of a design as experimental or SLSA and later granting a TC for the same design is a real problem and impediment to innovation. Perhaps some of the alphabet aviation organizations and their memberships would consider suggesting to the House and Senate General Aviation Caucuses that a change is needed. The House caucus just reached 200 members. Earl Lawrence (formerly of the EAA) now heads the small aircraft directorate. Perhaps there's a receptive ear there.



I'm not sure this goes far enough to help the gliding community.



http://www.kansas.com/2013/07/16/289...alization.html



Frank Whiteley

About 50 commercial entities...