# GP-5 or Polen Special similar designs.

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#### rv6ejguy

##### Well-Known Member
Up high, you don't need nearly as much hp so you're not pushing the engine very hard at all compared to Reno. Andy Findlay's Super Legacy trues 254 knots at 2500 rpm and 26 inches at 12,500 going cross country. Would do an easy 300 KTAS at 24,000 feet at less than 30 inches.

The OP was looking for a tandem though...

#### geraldmorrissey

##### Well-Known Member
Always thought it would be fun to scale up a F1 racer. Big comfortable cockpit, long wings, oxygen, baggage, fixed gear, 6 cylinders,, light weight, single seat. Think Shoestring or Rivets at 1.5 scale.

#### BJC

##### Well-Known Member
HBA Supporter
Always thought it would be fun to scale up a F1 racer. Big comfortable cockpit, long wings, oxygen, baggage, fixed gear, 6 cylinders,, light weight, single seat. Think Shoestring or Rivets at 1.5 scale.
Buy one here, but bring a big bag of money. MX Aircraft and Merchandise » MXS Aircraft

BJC

#### jac

##### Well-Known Member
The Falco Plans are on the net, Narrow the fuselage & up the powerplant, has retractable gear & do some serious math on the wing and structural stuff.

#### Hot Wings

##### Grumpy Cynic
HBA Supporter
Log Member
I've always wondered why this path hasn't had more attention or development for this type of mission.

AJ-2

#### Hephaestus

##### Well-Known Member
I've always wondered why this path hasn't had more attention or development for this type of mission.

AJ-2

View attachment 109848
Love the AJ2! Thanks for bringing that one up again. It's one I always forget the name of.

I dunno, everyone tells me I'm crazy for wanting the fast semi-efficient single place. To me - especially after the past year, that old PAV concept makes a lot of sense again. The cirrus has made big new inroads in that market once serviced by the bonanza. Surprised there's not a lot more interest in the 'not quite rich enough to buy a cirrus' and up-and-coming 'influencer' crowds.

Double post

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#### rv6ejguy

##### Well-Known Member
I like this concept but the stated cruise numbers at 55% and 75% power don't add up. If it does 200mph at 55%, It should do more like 222 mph at 75%, not 240 or 250.

Despite how sleek it looks however, it isn't any faster than Dave Ander's RV-4 or much faster than a clean IO-390 powered RV-8 (around same hp) like Dan Horton's.

#### Toobuilder

##### Well-Known Member
HBA Supporter
Log Member
Indeed Ross... I always liked the AJ-2, but its performance stats are far from breathtaking now that I read them.

#### Hot Wings

##### Grumpy Cynic
HBA Supporter
Log Member
The numbers may not be that impressive compared to some of today's aircraft but for a 40 year old design with only 22 hours of flight/development time it's initial numbers are pretty good, even by modern standards.

One can only wonder what they might be with the same amount of 'tuning' that has been expended on some of the aircraft we now consider impressive.

Jack Cox interview.

#### agpilot24

##### New Member
If I had the money.... this would be in my hangar. Not tandem seating, but kicks the snot out of most that are....
A modern day GeeBee

#### BoKu

##### Pundit
HBA Supporter
I'm looking to build a racer-type aircraft like the GP-5 or the Polen Special but can't find any plans for something like them. Specifically it must have centerline seating, neighborhood of 300mph vne, and perform well in cruse around 15,000 msl. What do you guys know of out there? Thanks!
Circling back to this original post, I'll add that it is important to remember the first rule of aerospace: No bucks, no Buck Rogers.

What makes the Polen special work so well is that it started out with a small airframe of relatively minimal size that was strategically enlarged to encompass increased performance. The wing is small and thin, and the fuselage stretch is mostly to accommodate a motor that does not have substantially greater frontal area than the original.

If I were to propose a solution, I think my general approach would be:

* Use as much off-the-shelf stuff as practical.

* Innovate sparingly.

* Engage expert help where needed.

For a single-seater, I'd probably start with an RV-4 fuselage and horizontal tail surfaces. I'd use reinforced tail spars and thicker tail skins, and use billet machined hinge parts instead of rod ends. For a two-seater, I'd start with the corresponding RV-8 parts. For the wing, I'd soft-tool a one-piece carbon fiber wing using a Steve Smith airfoil and pultrusion-based spar; the thickness would probably be around 11%. The spar would fit up into a slot in the fuselage under the Fx04 bulkhead. The engine would be a Lycoming 6-cylinder, with a turbo if necessary, with injection and front induction to keep the cowling slender. If retracts are necessary, I'd probably use standard Lancair or Glasair parts. The overall price tag would probably be somewhere between $150k and$200k.

#### cvairwerks

##### Well-Known Member
I really like that BJC suggested the Brokaw Bullet. It really is exactly what I was looking for. I hear that plans are rare so I'm going to start looking around. Does anyone have any leads as to where I could find the Brokaw Bullet plans?
Bullet plans are extremely rare. I don’t think Doc ever sold more than a dozen sets. I’ve chased trying to buy a set for more then 25 years now. I know of only three complete sets in the world right now. There was only one other Bullet built, and it’s current whereabouts are unknown.

#### thjakits

##### Well-Known Member
If \$ isn't a real factor - your best bet for a high/low-fast&far item is a NXT (I think "Relentless" is still on the market...). I saw a NXT with a twin-turbo 720 going 300 kts (GPS) at sealevel @ 30°C with no problems.....
[Yes I know - 250 max below 10k ft - this didn't happen in the US and it's still not legal here either, but it happened - MANY times...].
Unfortunately that particular NXT doesn't exist anymore, but there are still a few out there....
If solo long distance is your thing - I think the NXT is about the best you can get at this time (....before going into REALLY expensive Turboprop territory....) - It is a "offset"-2-seater, but really more a 1 1/2 seater - after all it was designed as a racer to spec for the rules at the time (....what gave a few lucky individuals a go at a NXT too).
I think you certainly could modify it to your travel likes easily if you stick to solo flying. That seat area should carry about anything you might want to bring!
Not sure about any details of "Relentless" (or any other NXT), but the one mentioned above had also a huge tank and according range.....
I think - today - if you build anything like a Polen, GP-4, Rocket, RV8, etc. from scratch and for speed - you probably end up spending close to what a used NXT goes for. Never mind the time you spend building bevor you go fast...

thjakits

#### Hephaestus

##### Well-Known Member
The Falco Plans are on the net, Narrow the fuselage & up the powerplant, has retractable gear & do some serious math on the wing and structural stuff.
Oh, are those plans a thing of beauty!

That's how plans should be drawn! Stelio Frati knows how to make a set of plans!

Might take some dynamic scaling... And 550kg empty weight seems to need some attention to lightening (if you don't need the +6/-3g)

#### rv6ejguy

##### Well-Known Member
If you can use side by side seating, a Lancair 360 with a turbo or Legacy does the numbers easily and are readily available to buy. Glasair III, same.

#### BJC

##### Well-Known Member
HBA Supporter
If you can use side by side seating, a Lancair 360 with a turbo or Legacy does the numbers easily and are readily available to buy. Glasair III, same.
And with either one, the pilot can see where to taxi on unfamiliar airports, unlike the NXT.

BJC

#### BoKu

##### Pundit
HBA Supporter
Stelio Frati knows how to make a set of plans!
The F8L plans were drawn by Alfred Scott based on Frati's drawings.

#### TarDevil

##### Well-Known Member
Jeff's Legend (now in other ownership) is available with a couple of auto derivative options. That's a sweet airframe.

#### rv6ejguy

##### Well-Known Member
The Legend is now in good hands with Bill Koleno, ex of Titan. They have many improvements coming for kits soon and have a good working relationship with Shane Daly of Innovative Wings here in Calgary who have been a leading modifier of Legends (first with the TPE-331 in Marty Abbott's Legend). I talked to Bill a couple weeks back and he may move forward on a V-8 version again. Bill is a really smart engineer with a huge passion for aircraft. Great guy IMO.