Hello Everyone
First let me introduce myself. I am an active World and European Aerobatic competitor.
I operate a Staudacher 300 airplane and I am delighted with it. With all my experience flying all tipes of aerobatic machines from Decathlons, Zlins, Yaks,Extras, Sukois, Staudachers and so on I am convinced on low weight as the way to go in Unlimited competition rather than extreme horsepower.
Seeing the latest Extras and Sbachs operating at only 2500 RPM from the bigs Lycomings 580 to stay ´´low´´ in front of the judges has convinced me in shaving more weight. Not pumping more ponies from my engine.
Right now, I am in a position where I have saved about 30 lbs from lots of parts but I am starting to get serius in more modifications. The next is the only fiberglas part still in the plane, the cowling and at 17 kg it is a heavy one.
I allso want someday to build my extreme Unlimited machine, and take this as a proyect to ecourage me to persue that dream...
I have been following this forum and have seen lots of experts and people that know ´´how to´´.
I have made my plug from foam shaped exact as the original. As my engine is reverse flow cowling (updraft) I rather stay with the original design and may choke a litle the inlets since it runs really cold in hot Spain.
I plan to cover it with fiberglas and either build the Carbon fiber cowling from the positive or may bult a famale and built it from the famale. Any opinions?
Also for the layups I planed on a vacum layup, but latelly I have been opting for a wetlayup. Any opinions? Can I built it as light with the wet layup? The cowling will be unpainted since it is allways hangared and when out it is always covered unless preparing for competition flight. A good CF looking finish is desired.
How about the layups. I have planed from outside to inside: several layers of Uni Carbon Fiber (4.7 Oz Unidirectional light weight) and one layer of kevlar (5 oz bidirectional). For the resin I am using Aeropoxy 2032 resin as I saw in the spects to be harder than WestSystem. The kevlar final layer is not have galvanic corrosion since there are plenty of aluminiun parts atached as the upper louvers (for updraft cowling), acces doors and to atach both parts of the cowling. Allso to the firewall atach points.
The big cuestion, how many layers? For the CF layers all aligned with the longitudinal axis or at 90º. For something as a cowling it is needed to be at 45º?
From guys that have made other cowlings tell me to be 3 layers and one more only at the atachmet points. Mine is big and allso produces tons of lift at high AOA since it is shaped like an airfoil. 3 (two of CF and one Kevlar) sounds not enought, any thougts?
I have a CF and Kevlar custom seating wich is hard as a rock and it is made of two layers of CF one Kevlar and one CF but since it was custom built I dont know the materials.
Answers, knowlage and help is very apreciated. Those of you who want to see my Staudacher hit N540SE at google and put pics. There are plenty to see the original cowling
Many thank to All
Jorge
First let me introduce myself. I am an active World and European Aerobatic competitor.
I operate a Staudacher 300 airplane and I am delighted with it. With all my experience flying all tipes of aerobatic machines from Decathlons, Zlins, Yaks,Extras, Sukois, Staudachers and so on I am convinced on low weight as the way to go in Unlimited competition rather than extreme horsepower.
Seeing the latest Extras and Sbachs operating at only 2500 RPM from the bigs Lycomings 580 to stay ´´low´´ in front of the judges has convinced me in shaving more weight. Not pumping more ponies from my engine.
Right now, I am in a position where I have saved about 30 lbs from lots of parts but I am starting to get serius in more modifications. The next is the only fiberglas part still in the plane, the cowling and at 17 kg it is a heavy one.
I allso want someday to build my extreme Unlimited machine, and take this as a proyect to ecourage me to persue that dream...
I have been following this forum and have seen lots of experts and people that know ´´how to´´.
I have made my plug from foam shaped exact as the original. As my engine is reverse flow cowling (updraft) I rather stay with the original design and may choke a litle the inlets since it runs really cold in hot Spain.
I plan to cover it with fiberglas and either build the Carbon fiber cowling from the positive or may bult a famale and built it from the famale. Any opinions?
Also for the layups I planed on a vacum layup, but latelly I have been opting for a wetlayup. Any opinions? Can I built it as light with the wet layup? The cowling will be unpainted since it is allways hangared and when out it is always covered unless preparing for competition flight. A good CF looking finish is desired.
How about the layups. I have planed from outside to inside: several layers of Uni Carbon Fiber (4.7 Oz Unidirectional light weight) and one layer of kevlar (5 oz bidirectional). For the resin I am using Aeropoxy 2032 resin as I saw in the spects to be harder than WestSystem. The kevlar final layer is not have galvanic corrosion since there are plenty of aluminiun parts atached as the upper louvers (for updraft cowling), acces doors and to atach both parts of the cowling. Allso to the firewall atach points.
The big cuestion, how many layers? For the CF layers all aligned with the longitudinal axis or at 90º. For something as a cowling it is needed to be at 45º?
From guys that have made other cowlings tell me to be 3 layers and one more only at the atachmet points. Mine is big and allso produces tons of lift at high AOA since it is shaped like an airfoil. 3 (two of CF and one Kevlar) sounds not enought, any thougts?
I have a CF and Kevlar custom seating wich is hard as a rock and it is made of two layers of CF one Kevlar and one CF but since it was custom built I dont know the materials.
Answers, knowlage and help is very apreciated. Those of you who want to see my Staudacher hit N540SE at google and put pics. There are plenty to see the original cowling
Many thank to All
Jorge
