Freebird free downloadable plans for improved KR2S

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cluttonfred

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I am sure other folks here are tracking this, but I just learned about it.

The Freebird project is a collaborative effort by KRnet members to provide FREE downloadable plans and drawings to enable builders to create their own homebuilt experimental aircraft. This aircraft is based on the evolution of the most recent generation of the KR series of homebuilt aircraft. Plans for the KR aircraft are no longer available for sale, so FreeBird plans will more than fill that gap, providing much needed detail, corrections, and more importantly, significant but proven changes to the overall design....”

 

Tiger Tim

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I understand that saving money on plans is probably a false economy but this is still exciting stuff.
 

Vigilant1

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Thanks, Matt, I'm looking forward to developments.

From their landing page: Attributes of the "Freebird"

-Longer fuselage -reduces pitch sensitivity and improves stability
-Wider fuselage - to fit normal size pilots and passengers
-Taller fuselage - to provide more headroom
-Larger but lighter Dragonfly canopy - better visibility, several configurations
-Taller vertical stabilizer and rudder - for improved lateral stability
-Split flaps - for lower landing speed and higher drag during rollout
-More efficient ailerons - further outboard, with internal balancing
-Several engine options - Corvair, Continental O-200, Lycoming, etc.
-Taildragger, tri-gear, and wheel/brake option details (and sources)

- Its not clear if the final specs of the Freebird have been published yet. The plans are to be released in a few months, but has "the group" already identified the target empty weight, internal cockpit width, wingspan, wing area, MTOW (assuming the spar is being designed to some MTOW) etc?
- It looks like the VW engine won't be explicitly within the scope of this project. IMO, that's too bad. About 60% of the existing KR2s shown on their spreadsheet are powered by VW variants. With enough wing, a 2180cc or bigger VW can power a KR-type design as they have for decades. The VW may not be ideal. but it would be a shame to write them out of the picture. Sonerai Iis, Sonexes, Cygnets, KR2, Thatcher CX5, etc-- two place planes with VW power are here, and now we have CF pultrusions and relatively cheap CF fabric. However, the days of cheap used O-200s are gone.

Anyway, an interesting effort.
 
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rv7charlie

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There was a recent mag article about the KR2 that mentioned the mods & resulting new open source design. They interviewed Rand's widow, who talked about the mods and the plans project. She basically said that she just wished they'd call it something other than a KR2, since there were so many mods that it really wasn't a KR2 anymore. Sounds like they're respecting her wishes.

I hadn't paid much attention to KR2s since the early '90s when I sat in one as a student pilot and at 160 lbs, took up about 1 1/2 seats in it, so when one of our EAA chapter members said he was putting an O290 in one, I was pretty sure he was playing with less than a full deck. Still not convinced, but maybe the mods are so extensive that it could happen safely.
 

rv7charlie

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The original 2 seat is really a comfortable single seat with no wasted space at all, if you're of current typical USA proportions. 180-200 lbs of average height human will fill one up.
 

Victor Bravo

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Isn't this also the same concept that Azalea Aviation was trying to achieve with their Saberwing... the KR-2.0? I understand it is not the same aircraft, but how much different did (two separate attempts to do the same thing) turn out?
 

Vigilant1

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And there was also the KRSuper2
(An effort that appears to have gone dormant, but did have a few examples under construction):

Design Parameter
KR-Super2KR-2S
Length19'16'
Wing Span24'23'
Total Wing Area93 sq ft82 sq ft
Empty Weight750 lbs620 lbs
Gross Weight1300 lbs980 lbs
Useful Load550 lbs360 lbs
Fuel Cap26 gal16 gal
Stall Speed48 mph52 mph
Maximum Speed170 mph155 mph
Cruise Speed140 mph140 mph
Range600 miles500 miles
EngineCorvair 2700VW 2180
Power100 HP70 HP
Power Loading13 lbs/hp14 lbs/hp
Wing Loading14 lbs/sq ft12 lbs/sq ft
Fuel Consumption5.5 gph4.5 gph
Seating2 side by side2 side by side
Geartri-grearconventional
Cabin Width43"38"
Azalea Aviation (Bill Capp's Saberwing) is kit-only and has a lot of parts created in female molds, so while it is a small composite 2seater, it diverges quite a bit from the KR in my opinion.

The Freebird appears to be a more direct continuation of the original KR project, incorporating a lot of things learned over the decades but being able to be built from plans (if desired) and presumably using the same basic construction techniques (wood and fiberglass). Or, maybe not. The "formality" of the entity behind the Freebird project isn't explicitly stated on the linked page.

The KR2 has a rich history, this will be interesting to see.
 
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jedi

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And there was also the KRSuper2
(An effort that appears to have gone dormant, but did have a few examples under construction):

Design Parameter
KR-Super2KR-2S
Length19'16'
Wing Span24'23'
Total Wing Area93 sq ft82 sq ft
Empty Weight750 lbs620 lbs
Gross Weight1300 lbs980 lbs
Useful Load550 lbs360 lbs
Fuel Cap26 gal16 gal
Stall Speed48 mph52 mph
Maximum Speed170 mph155 mph
Cruise Speed140 mph140 mph
Range600 miles500 miles
EngineCorvair 2700VW 2180
Power100 HP70 HP
Power Loading13 lbs/hp14 lbs/hp
Wing Loading14 lbs/sq ft12 lbs/sq ft
Fuel Consumption5.5 gph4.5 gph
Seating2 side by side2 side by side
Geartri-grearconventional
Cabin Width43"38"
Azalea Aviation (Bill Capp's Saberwing) is kit-only and has a lot of parts created in female molds, so while it is a small composite 2seater, it diverges quite a bit from the KR in my opinion.

The Freebird appears to be a more direct continuation of the original KR project, incorporating a lot of things learned over the decades but being able to be built from plans (if desired) and presumably using the same basic construction techniques (wood and fiberglass). Or, maybe not. The "formality" of the entity behind the Freebird project isn't explicitly stated on the linked page.

The KR2 has a rich history, this will be interesting to see.
Super 2 wing loading 14 lbs/sq ft versus 12 for the 2S. Stall speed 48 for the Super 2 versus 52 for the 2S.

How is this accomplished?
 

Vigilant1

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Super 2 wing loading 14 lbs/sq ft versus 12 for the 2S. Stall speed 48 for the Super 2 versus 52 for the 2S.

How is this accomplished?
He was building slotted flaps for the Super 2, so I suppose he postulated a better Cl. He didn't say whether the stall speed quoted was clean or dirty.
 

Tiger Tim

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A few years ago, TEAM Aircraft provided free downloads of plans for all their MAX designs in an effort to generate more enthusiasm for them. I never heard how well the idea worked...
They stopped doing it, which might be indicative of how well it went. I highly suspect that the support they were providing to some of the cheap-Os who pounce on ‘free’ was costing the company too much.
 

TFF

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Free and being in business belittles your product. Falco is out of business and no one was going to buy it so that’s a good reason to make it free.
 

rv7charlie

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Free and being in business belittles your product. Falco is out of business and no one was going to buy it so that’s a good reason to make it free.
Try telling that to the linux userbase. ;-) You can be certain that these messages are passing through at least a half dozen linux systems to get to us, and all of them are making money off it, and they are all paying for tech support. There are effective business plans beyond charging for the primary product. Anyone use Chrome, or Firefox, or [etcetc] as their browser? What about gmail? When's the last time you paid money for an internet search? You can be sure that Google and the other search engines are profiting from your 'free' access.
 

TFF

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The owner of the IP isn’t making money giving it away for free. Falco for free is costing the owners after they shut the door, that is noble. Free semantics. The person getting in in their hands without paying is free.

The big proof of free killing a product was Opra giving away all those G6s. GM never got to ride the new release high. They gave it away.
 
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