Re: [RCSE] airfoils for EPP wings
(pardon me if this is a duplicate, I didn't see the previous on get through...) I do like the carefree nature of EPP wings. Here is a tip for when you start flying with a composite wing -- learn to catch the plane by the nose. Now that I do that I'm much less concerned about putting (more) dents in my composite wing. I agree that the Goblin and Dizzy Bird wings don't penetrate. It acts like it is a high drag wing. Even at slow speeds it sinks through really light stuff. I recently built a Little Nipper style wing for the Goblin: white foam, SD7003, same span but less chord than the Goblin (less area), 1 oz lighter than the Goblin wing. It makes the Goblin a different plane: much better penetration, won't go as slow, doesn't have as much drag (and decent) in light lift. It's a step in the right direction so I'll change some things and try another wing soon. I wonder if I can find some EPP? > Actually, there was another one where they built full size > man-carrying gliders and launched them off a slope (the idea > being to see how far down the slope you could fly). It was > a bit scary...one of them got hit by a cross wind gust just > as it got a few feet off the ground. There wasn't enough > control authority to over come it, and the glider crashed. > Luckily, the pilot wasn't injured, but he could have easily > been killed if the glider had managed to get higher before > it happened. I recall from the replay of that crash that the "expert" moved the controls into the turn instead of opposite! Keith Watson Wilsonville, OR RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
Re: [RCSE] airfoils for EPP wings
I do like the carefree nature of EPP wings. Here is a tip for when you start flying with a composite wing -- learn to catch the plane by the nose. Now that I do that I'm much less concerned about putting (more) dents in my composite wing. I agree that the Goblin and Dizzy Bird wings don't penetrate. It acts like it is a high drag wing. Even at slow speeds it sinks through really light stuff. I recently built a Little Nipper style wing for the Goblin: white foam, SD7003, same span but less chord than the Goblin (less area), 1 oz lighter than the Goblin wing. It makes the Goblin a different plane: much better penetration, won't go as slow, doesn't have as much drag (and decent) in light lift. It's a step in the right direction so I'll change some things and try another wing soon. I wonder if I can find some EPP? > Actually, there was another one where they built full size > man-carrying gliders and launched them off a slope (the idea > being to see how far down the slope you could fly). It was > a bit scary...one of them got hit by a cross wind gust just > as it got a few feet off the ground. There wasn't enough > control authority to over come it, and the glider crashed. > Luckily, the pilot wasn't injured, but he could have easily > been killed if the glider had managed to get higher before > it happened. I recall from the replay of that crash that the "expert" moved the controls into the turn instead of opposite! Keith Watson Wilsonville, OR RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
Re: [RCSE] airfoils for EPP wings
I saw that episode, those both needed to be building planes out of EPP... Kristopher - Original Message - From: "Brett Jaffee" <[EMAIL PROTECTED]> To: "Henke, Steve" <[EMAIL PROTECTED]> Cc: <[EMAIL PROTECTED]> Sent: Thursday, February 07, 2002 4:52 PM Subject: Re: [RCSE] airfoils for EPP wings > "Henke, Steve" wrote: > > > > >Did you ever see the episode of Junkyard Wars where they > > built gliders? > > > > do you mean the bomb drop episode? > > Actually, there was another one where they built full size man-carrying gliders and launched them off a slope (the idea being to see how far down the slope you could fly). It was a bit scary...one of them got hit by a cross wind gust just as it got a few feet off the ground. There wasn't enough control authority to over come it, and the glider crashed. Luckily, the pilot wasn't injured, but he could have easily been killed if the glider had managed to get higher before it happened. > > RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED] > RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
Re: [RCSE] airfoils for EPP wings
"Henke, Steve" wrote: > > >Did you ever see the episode of Junkyard Wars where they > built gliders? > > do you mean the bomb drop episode? Actually, there was another one where they built full size man-carrying gliders and launched them off a slope (the idea being to see how far down the slope you could fly). It was a bit scary...one of them got hit by a cross wind gust just as it got a few feet off the ground. There wasn't enough control authority to over come it, and the glider crashed. Luckily, the pilot wasn't injured, but he could have easily been killed if the glider had managed to get higher before it happened. RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
RE: [RCSE] airfoils for EPP wings
>Did you ever see the episode of Junkyard Wars where they built gliders? do you mean the bomb drop episode? one team built a powered RC plane with a scrap foam wing, RC car radio gear and a gas engine out of a leaf blower or weedeater. the other team built a helium balloon powered with electric motors. It was frustrating to watch because they both flew like crap and the "expert" on the foam wing plane team was an imbecile..a glider design could have won since they launched from up on a high bank and the bomb drop target was below them. -Original Message- From: Andrew E. Mileski [mailto:[EMAIL PROTECTED]] Sent: Thursday, February 07, 2002 1:53 PM To: [EMAIL PROTECTED] Subject: Re: [RCSE] airfoils for EPP wings widlerj wrote: > > So what are your suggestions for a different airfoil bearing in mind > that I can not get or maintain a truly accurate foil shape? I can > read polar graphs but have no idea how sensitive different airfoils > are to irregularities. *chuckle* Did you ever see the episode of Junkyard Wars where they built gliders? Their airfoils weren't computer plotted or accurately skinned, yet they flew. Go figure :^) I think that some of the best airfoils may never be discovered by analyzing a computer model alone. You can have a whole lot of fun, and learn a whole lot too, by just free-hand drawing an airfoil and trying it out. One day we might all be using airfoils labeled with your initials :) -- Andrew E. Mileski RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED] RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
Re: [RCSE] airfoils for EPP wings
widlerj wrote: > > So what are your suggestions for a different airfoil bearing in mind > that I can not get or maintain a truly accurate foil shape? I can > read polar graphs but have no idea how sensitive different airfoils > are to irregularities. *chuckle* Did you ever see the episode of Junkyard Wars where they built gliders? Their airfoils weren't computer plotted or accurately skinned, yet they flew. Go figure :^) I think that some of the best airfoils may never be discovered by analyzing a computer model alone. You can have a whole lot of fun, and learn a whole lot too, by just free-hand drawing an airfoil and trying it out. One day we might all be using airfoils labeled with your initials :) -- Andrew E. Mileski RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
[RCSE] airfoils for EPP wings
I know the disadvantages of EPP wings such as the difficulty of maintaining a true airfoil, lack of stiffness especially in torsion, "prune skin" and surface imperfections caused by the underlying tape, different behavior in different air temperatures, etc. I have even posted regarding the unsuitability of EPP for core material. However due to my ham-like hands catching my HLG's is very rough on the wings. EPP seems the way to go for durability. I am encouraged by my Goblin which has held up well and suits my needs pretty well. My Ghost (basically a Dizzy Bird) has climbed out to thermals and literally soared with the hawks and buzzards on many occasions. This suits my flying style very well but I am wondering if a different airfoil might be of benefit. The Ghost and the Goblin have fairly highly under cambered foils and are not very good at penetration. So what are your suggestions for a different airfoil bearing in mind that I can not get or maintain a truly accurate foil shape? I can read polar graphs but have no idea how sensitive different airfoils are to irregularities. Also, when I get to the point of moving up to non EPP wings, what construction should I consider for durability? Thanks Wid RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
