Posted by Jwmflying14 |
Aug 10, 2014 @ 11:33 AM | 1,619 Views
As I am working towards a long distance flight with a certain, high endurance airframe, I decided it was time to attack the "small things."
My experience in the full-sale world shows that even the small things, when added up, make a huge difference.
To date, I have a fix for essentially the worst aerodynamic shape you can imagine, Cylinders.... Generally when flying UHF, people use straws (I used to prefer a coffee mixer/straw) to hold the antennas directly straight up and straight down. My fix for this was a tiny 3d printed fairing. So what does it really improve in the long run? Who knows... probably not much... However it test flights, the antenna stays fixed and has much less vibration.
The second is creating a more efficient spinner for a pusher configured aircraft. The craft its self was designed around a laminar fuselage. Pusher configured aircraft often have less surface friction, and can be designed with a nice laminar flow, whereas tractor configured aircraft are often more efficient at the prop, however suffer greatly by the disturbed airflow over the fuselage.
A great demonstration of an efficient use of a pusher configuration is Burt Rutans Varieze, which with the proper spinner, is actually a very efficient aircraft when compared to others in the same class.
The Pressure-recovery spinner is designed to fit 50mm firwalls. The spinner is now on its 5th iteration, and shows a 27% decrease in drag In just this area alone. What does this...Continue Reading
Posted by Jwmflying14 |
Sep 03, 2012 @ 12:18 AM | 4,293 Views
After doing some work on a highspeed F5D Forward Swept Wing, I decided to apply what I learned into the DLG world. I have taken my own personal blend of the Zone V2 Airfoils and Drela's Ag455 airfoil. Came up with a nice CL/CD, and what appears to be a shallow stall. It is the MOST forgiving when it comes to fine tuning the CL/CD:AoA but, once achieved it seems to have a VERY high CL/CD
Forward swept wing to help incorporate the aerodynamic advantages, and inherent stability they add. I added my own blend of 3 different foils along with twist and dihedral in the tips, almost entirely getting rid of vorticies between stall and 28 mph, then they are almost nonexistent until 100 mph. PLenty of range for a DLG. According to software it also doesn't seem to want to stall out the tips either, Thus meaning no more dropped wings when trying to stay in that thermal!
Building disadvantages are complex cores, or molding. And throwing peg interference. You will no longer be able to get the throwing Peg as far back as other wings, however I think it is definitely an advantage I would give up.
This is just a gallery to serve as a gallery For my father to check out.
This airframe was received generously as a FreeBee, However I never got a good chance to work on it as I was offered a smokin deal on the TS2 Disser to replace a DLG that I broke due to a bad build/unclear instructions.
Hey Dad, Im thinkin you will really enjoy this whole Discus Launch Glider thing. It tons of fun to just give it a nice good spin and all of a sudden be 180' high. They thermal in next to nothing and it is very easy to find thermals. I'll help you With setting and adjusting everything. Starting with Aileron position. It will be beneficial to set up multiple flight modes. By this I mean a Penetrate mode (ailerons ~2-3mm up), Best Glide (0mm of aileron, perfect airfoil), Cruise ( about 3mm down) and thermal (about 6-8mm down). You will also need a launch mode which is often somewhere between 0-3mm up aileron, mixed with an up elevator trim. This allows minimal parasitic drag from the airfoil (drag being a byproduct of ALL lift inducing surfaces) and some up elevator which allows the plane to naturally climb up at about an 80 degree angle till almost stall speed then level out.
Your gonna have a Blast with this thing! scratching can be the most fun you can have and its fun as hell to get a 3-5minute flight Which took a solid 5 minutes of work and concentration.
It has some minor Defects But nothing to hard to fix! There are two cracks in the Fuse, which a simple SINGLE...Continue Reading
Posted by Jwmflying14 |
Jun 25, 2012 @ 12:30 AM | 5,607 Views
Well Here it goes! I originally Started this as I wanted a mid level DLG. I had previously broken a Super mini Topsky and the guys at skip miller were kind enough to offer me a pretty darn good deal on the Tsky 2.0 Disser. However At the same time I read up on the P2 and its amazing performance for the cost and couldn't help myself. So I got pulled some strings and got a bulk deal going. Now all 6 airframes have been ordered and we will be getting them mid August! This gives me plenty of time to properly, and skillfully build My Disser, as well as fly the piss out of it! Then when my P2 Low Wing comes, I will do the same with it =]]