Original Posted By: Dmott9(at)aol.com
Subject: Pietenpol-List: Piet vs Fly BabyOk, folks. I've been looking around at other designs. Latest is the Fly Baby. The more I look at the design, it looks more like a Piet.So the question:WHY does the Fly Baby have a much faster cruise speed, on roughly the same engine, same frontal profile etc.? Is it the wing?About that wing, much simpler rib design, roughly same weight.In my looking around, recommended tire is 8.00 x 4 Is this hard to find and would it work on a Piet ?-dennis the menace________________________________________________________________________________
Pietenpol-List: Piet vs Fly Baby
RE: Pietenpol-List: Piet vs Fly Baby
Original Posted By: "Joe Krzes"
-----Original Message-----Ok, folks. I've been looking around at other designs. Latest is the FlyBaby.The more I look at the design, it looks more like a Piet.So the question:WHY does the Fly Baby have a much faster cruise speed, on roughly the sameengine, same frontal profile etc.? Is it the wing?About that wing, much simpler rib design, roughly same weight.In my looking around, recommended tire is 8.00 x 4Is this hard to find and would it work on a Piet ?-dennis the menaceDennis,I'll have to look at my brother's set of Fly Baby plans, but I think theanswer to your first question has to do with wing area. As I recall, theFly Baby is a little lighter (605 lbs. empty vs. BHP's figure of 610 lbs,which I for one consider a little optimistic), and more importantly it hasless wing area (120 sq. ft. vs. the Piet's 145 sq. ft.). Less wing areagenerally equates to less induced drag.I think the parasol wing configuration of the Piet contributes quite a bitof drag. I don't know this for a fact, but it would appear that thedownwash from the centersection interfering with the open cockpits and allthe bracing wires between the fuselage and the centersection would add a lotof drag. That's probably one reason there haven't been very many parasolwing airplanes designed. This design type flourished in the late 20's andearly 30's (Pietenpol, Corben Baby Ace, Heath Parasol, Fairchild 22,Lockheed Air Express, etc.), but there haven't been too many designed since(with the notable exception of the Pober Pixie - also the prototype BellancaDecathlon was a parasol. I saw it at an airshow in 1970. I wonder whatever happened to it?).Anyway, the low wing configuration is quite a bit cleaner. Also, the factthat the Fly Baby carries its control cables internally, rather thanflopping about in the breeze - round cable is incredible in the amount ofdrag it produces - helps reduce drag. As does having just one cockpitrather than the two cockpits of the Pietenpol.The Fly Baby is a very nice airplane. Well thought out, well designed.When built to the plans it is very strong. I would build one except that Ilike to take people flying and if I'm going to build a single seat airplane,it is going to have a hell of a lot more aerobatic capability than a FlyBaby (like, maybe a Pitts Special)As for the tires, the 8.00 x 4 was the standard J-3 Cub wheel and tire.They are still readily avalable, with wonderfully weak hydraulic expandertube drum brakes. You occasionally see them up for auction on eBay.Jack________________________________________________________________________________
-----Original Message-----Ok, folks. I've been looking around at other designs. Latest is the FlyBaby.The more I look at the design, it looks more like a Piet.So the question:WHY does the Fly Baby have a much faster cruise speed, on roughly the sameengine, same frontal profile etc.? Is it the wing?About that wing, much simpler rib design, roughly same weight.In my looking around, recommended tire is 8.00 x 4Is this hard to find and would it work on a Piet ?-dennis the menaceDennis,I'll have to look at my brother's set of Fly Baby plans, but I think theanswer to your first question has to do with wing area. As I recall, theFly Baby is a little lighter (605 lbs. empty vs. BHP's figure of 610 lbs,which I for one consider a little optimistic), and more importantly it hasless wing area (120 sq. ft. vs. the Piet's 145 sq. ft.). Less wing areagenerally equates to less induced drag.I think the parasol wing configuration of the Piet contributes quite a bitof drag. I don't know this for a fact, but it would appear that thedownwash from the centersection interfering with the open cockpits and allthe bracing wires between the fuselage and the centersection would add a lotof drag. That's probably one reason there haven't been very many parasolwing airplanes designed. This design type flourished in the late 20's andearly 30's (Pietenpol, Corben Baby Ace, Heath Parasol, Fairchild 22,Lockheed Air Express, etc.), but there haven't been too many designed since(with the notable exception of the Pober Pixie - also the prototype BellancaDecathlon was a parasol. I saw it at an airshow in 1970. I wonder whatever happened to it?).Anyway, the low wing configuration is quite a bit cleaner. Also, the factthat the Fly Baby carries its control cables internally, rather thanflopping about in the breeze - round cable is incredible in the amount ofdrag it produces - helps reduce drag. As does having just one cockpitrather than the two cockpits of the Pietenpol.The Fly Baby is a very nice airplane. Well thought out, well designed.When built to the plans it is very strong. I would build one except that Ilike to take people flying and if I'm going to build a single seat airplane,it is going to have a hell of a lot more aerobatic capability than a FlyBaby (like, maybe a Pitts Special)As for the tires, the 8.00 x 4 was the standard J-3 Cub wheel and tire.They are still readily avalable, with wonderfully weak hydraulic expandertube drum brakes. You occasionally see them up for auction on eBay.Jack________________________________________________________________________________
Re: Pietenpol-List: Piet vs Fly Baby
Original Posted By: Jack Phillips
----- Original Message -----
----- Original Message -----
RE: Pietenpol-List: Piet vs Fly Baby
Original Posted By: owner-pietenpol-list-server(at)matronics.com
Absolutely right, Mike. This is what happens when you can type faster thanyou can think. Anyway, the upshot is, the smaller wing of the Fly Baby hasless overall drag associated with it. The whole airplane is a cleanerdesign (you'd expect that, since it is 30 years newer).Jack -----Original Message-----
Absolutely right, Mike. This is what happens when you can type faster thanyou can think. Anyway, the upshot is, the smaller wing of the Fly Baby hasless overall drag associated with it. The whole airplane is a cleanerdesign (you'd expect that, since it is 30 years newer).Jack -----Original Message-----