New low budget two seater

On Friday, June 15, 2018 at 12:26:35 PM UTC-7, Paul Agnew wrote:
Meanwhile, the jigs for the Peregrine (Krosnos) are just sitting in shipping containers somewhere in Georgia. Could it be produced cost-effectively?

As I understand it, the problem with the Krosnos is that the engineering and certification are based on material specifications and thicknesses common in Europe but basically unobtanium here in the US. You'd need to either source all your materials from Europe, or re-engineer the aircraft to use US materials and thicknesses.

As a practical matter, it's not that hard. As a regulatory matter, however, it's a huge paperwork effort to go through every single blueprint and justify the change from some metric thickness to the nearest inch size. You basically have to re-engineer the entire structure.

Sourcing materials from Europe is a huge gamble. Here in the US there is a fairly fat supply pipeline supporting the homebuilt aircraft movement that currently produces the majority of all new general aviation aircraft. In Europe, the pipeline is a lot thinner and has a lot more friction and regulatory risk aversion, so it is likely that material costs would be a lot more.

Furthermore, given that prices for carbon fiber in terms of cost per unit mass and cost per unit stiffness are steadily declining, I think that carbon fiber is the way to go for any new design, even for a primary trainer.

Thanks, Bob K.

Another hurdle in producing the Puchatek / Krosno / Peregrine:
From memory, the existing 5000-hour limit never got to the point of having an inspection program for extension. This was to be worked on, but then Barry Aviation was awarded a contract that kept them quite busy.
The glider is a decent trainer: Roomy cockpit, good visibility, instruments front and rear, spin capable, aerotow or winch launching.
Jim


On Friday, June 15, 2018 at 1:14:31 PM UTC-7, Bob Kuykendall wrote:
On Friday, June 15, 2018 at 12:26:35 PM UTC-7, Paul Agnew wrote:
Meanwhile, the jigs for the Peregrine (Krosnos) are just sitting in shipping containers somewhere in Georgia. Could it be produced cost-effectively?

As I understand it, the problem with the Krosnos is that the engineering and certification are based on material specifications and thicknesses common in Europe but basically unobtanium here in the US. You'd need to either source all your materials from Europe, or re-engineer the aircraft to use US materials and thicknesses.

As a practical matter, it's not that hard. As a regulatory matter, however, it's a huge paperwork effort to go through every single blueprint and justify the change from some metric thickness to the nearest inch size. You basically have to re-engineer the entire structure.

Sourcing materials from Europe is a huge gamble. Here in the US there is a fairly fat supply pipeline supporting the homebuilt aircraft movement that currently produces the majority of all new general aviation aircraft. In Europe, the pipeline is a lot thinner and has a lot more friction and regulatory risk aversion, so it is likely that material costs would be a lot more.

Furthermore, given that prices for carbon fiber in terms of cost per unit mass and cost per unit stiffness are steadily declining, I think that carbon fiber is the way to go for any new design, even for a primary trainer.

Thanks, Bob K.

Never mind, one day the US will progress past the 19th century and use the metric system.

On Friday, June 15, 2018 at 2:14:31 PM UTC-6, Bob Kuykendall wrote:
On Friday, June 15, 2018 at 12:26:35 PM UTC-7, Paul Agnew wrote:
Meanwhile, the jigs for the Peregrine (Krosnos) are just sitting in shipping containers somewhere in Georgia. Could it be produced cost-effectively?

As I understand it, the problem with the Krosnos is that the engineering and certification are based on material specifications and thicknesses common in Europe but basically unobtanium here in the US. You'd need to either source all your materials from Europe, or re-engineer the aircraft to use US materials and thicknesses.

As a practical matter, it's not that hard. As a regulatory matter, however, it's a huge paperwork effort to go through every single blueprint and justify the change from some metric thickness to the nearest inch size. You basically have to re-engineer the entire structure.

Sourcing materials from Europe is a huge gamble. Here in the US there is a fairly fat supply pipeline supporting the homebuilt aircraft movement that currently produces the majority of all new general aviation aircraft. In Europe, the pipeline is a lot thinner and has a lot more friction and regulatory risk aversion, so it is likely that material costs would be a lot more.

Furthermore, given that prices for carbon fiber in terms of cost per unit mass and cost per unit stiffness are steadily declining, I think that carbon fiber is the way to go for any new design, even for a primary trainer.

Thanks, Bob K.

Yes, materials were part of the problem, Polish aluminum and Russian steel (not stamped but dated with a Sharpie), though Tim seemed to indicate substitution could be done. When surveyed, the majority of operators preferred metal over composites, but that survey is several years old now. Barry Aviation got as far as PMA and had set up the assembly line, but never achieved manufacturing certification. You have to be able to keep the lights on for a year or two at your manufacturing facility. Three have to be built under FAA observation in order to become self-certifying. If they don't like something, they leave and you will not see them again for months. Didn't seem to be a fix it and we'll come back when you're ready, we'll schedule a return when we're ready. In any event, the economy dumped in 2008 and they couldn't keep the facility open. Tim estimated a trained crew could build one per week.

Frank W

Bob,

Would this be a production aircraft or a kit?

On 6/15/2018 12:48 PM, Bob Kuykendall wrote:
I've just started a Facebook page to discuss and promote the idea of an open-source crowd-sourced two-seat primary trainer certified as SLSA or whatever makes it eligible for commercial ride, instruction, and rental use. I envision something about halfway between the ASK13 and ASK21 in performance and complexity, and designed to fill in for the declining 2-33 population.

I'm not extremely optimistic about this effort, but as one of the few sailplane developers with a vested interest in the future of soaring in the US I thought I'd get the conversation going and see where it leads.

https://www.facebook.com/SoarOpenTrainer

--Bob K.

--
Dan, 5J

On Friday, June 15, 2018 at 2:48:48 PM UTC-4, Bob Kuykendall wrote:
I've just started a Facebook page to discuss and promote the idea of an open-source crowd-sourced two-seat primary trainer certified as SLSA or whatever makes it eligible for commercial ride, instruction, and rental use. I envision something about halfway between the ASK13 and ASK21 in performance and complexity, and designed to fill in for the declining 2-33 population.

I'm not extremely optimistic about this effort, but as one of the few sailplane developers with a vested interest in the future of soaring in the US I thought I'd get the conversation going and see where it leads.

https://www.facebook.com/SoarOpenTrainer


I've not completely given up on R.A.S. just yet, so I'll ask my question here. Why would this project produce two place trainers that were less expensive than the PW-6 built in Poland? BTW, the PW-6 performance is very close to the ASK21, I assume it would have better performance than the SoarOpenTrainer.

I've not completely given up on R.A.S. just yet, so I'll ask my question here. Why would this project produce two place trainers that were less expensive than the PW-6 built in Poland? BTW, the PW-6 performance is very close to the ASK21, I assume it would have better performance than the SoarOpenTrainer.

My personal take would be to make a metal or metal and fabric ASK-13ish kit.. Sonex type airframe kits are around 25K Say you could get a two seater high twenties to one, for 30K and easyish to build. Make sure it can take two big pilots. Dunno if it would sell. Composite makes better sailplanes, but I have no interest in working with the stuff, no idea how universal that feeling is.
On the other point. What great days when American newspaper editorials openly advocated for America to invade and take over Canada. Was but a mere 100 years ago. Think of how great that would be for Canada. They'd be Americans so they wouldn't have to feel like a second world country and the world would be rid of that dress wearing son of a commie prime minister.

On Saturday, June 16, 2018 at 6:11:08 PM UTC-7, son_of_flubber wrote:
Why would this project produce two place trainers that were less expensive than the PW-6 built in Poland?

Before or after the Trade Wars?

On Saturday, June 16, 2018 at 7:11:08 PM UTC-6, son_of_flubber wrote:
On Friday, June 15, 2018 at 2:48:48 PM UTC-4, Bob Kuykendall wrote:
I've just started a Facebook page to discuss and promote the idea of an open-source crowd-sourced two-seat primary trainer certified as SLSA or whatever makes it eligible for commercial ride, instruction, and rental use. I envision something about halfway between the ASK13 and ASK21 in performance and complexity, and designed to fill in for the declining 2-33 population.

PW-6 is a glider rather for Chinese, not for Americans ;-)