FlyingWing2
Name: FlyingWing2
Date: December 2011
Material: R20 Pink Foam
Airfoil: Sipkill 1,7/10b
Wingspan: 55 cm
Root chord: 18 cm
Tip chord: 18 cm
Sweep: 30 degrees
Propeller: 7 x 3.5
Motor: 18T TowerPro brushless
Battery: Turnigy 3S 1100 mAh LiPo
Design:
This was my first designed flying wing. After doing some research in the design of flying wings, I found that I needed to have winglets (these are the vertical triangular pieces on the ends of the wing). Winglets help a lot with stability and control of the airplane, and all the flying wings I designed need winglets to fly. I tried flying this plane without the winglets and it was impossible to control. I also found that many people recommended having the wings swept back 30 degrees, which I incorporated into my design.
The airfoil was chosen from the Airfoil Database for Tailless and Flying Wings (www.aerodesign.de/english). This airfoil is designed for combat flying and I chose it because I thought my first plane should be more durable since I was teaching myself to fly flying wings. However, when I later re-read the description on the website, I found that this airfoil produces more drag because it is thicker in the middle.
Here are some websites I used in my research:
http://adamone.rchomepage.com/index2.htm
http://www.mh-aerotools.de/airfoils/flywing1.htm
http://www.nurflugel.com/Nurflugel/n_o_d/weird_02.htm
Date: December 2011
Material: R20 Pink Foam
Airfoil: Sipkill 1,7/10b
Wingspan: 55 cm
Root chord: 18 cm
Tip chord: 18 cm
Sweep: 30 degrees
Propeller: 7 x 3.5
Motor: 18T TowerPro brushless
Battery: Turnigy 3S 1100 mAh LiPo
Design:
This was my first designed flying wing. After doing some research in the design of flying wings, I found that I needed to have winglets (these are the vertical triangular pieces on the ends of the wing). Winglets help a lot with stability and control of the airplane, and all the flying wings I designed need winglets to fly. I tried flying this plane without the winglets and it was impossible to control. I also found that many people recommended having the wings swept back 30 degrees, which I incorporated into my design.
The airfoil was chosen from the Airfoil Database for Tailless and Flying Wings (www.aerodesign.de/english). This airfoil is designed for combat flying and I chose it because I thought my first plane should be more durable since I was teaching myself to fly flying wings. However, when I later re-read the description on the website, I found that this airfoil produces more drag because it is thicker in the middle.
Here are some websites I used in my research:
http://adamone.rchomepage.com/index2.htm
http://www.mh-aerotools.de/airfoils/flywing1.htm
http://www.nurflugel.com/Nurflugel/n_o_d/weird_02.htm
Construction:
I used a homemade hot wire foam cutter to cut the foam wing. I chose to use R20 insulation foam, which can be purchased from Home Depot because it is significantly less expensive than balsa, and it can be cut with a hot wire.
The foam is not covered with anything, but there is a piece of sheet metal on the bottom, which wraps around the leading edge of the wing. This was added on because after the first few crashes, the front of the wing broke off and I needed something to hold the battery in place.
Spar - Two 1/4" x 1/8" pieces of spruce; run along the length of the wing
Elevons - Cut back of airfoil and beveled 45 degrees
Similar to - EPP Assassin [found online]
I used an online tool to find out where the Centre of Gravity (CG) should be (http://fwcg.3dzone.dk). Through experimentation, I found that this online tool is fairly accurate - a good starting point for experimentation. The CG should be within the boundaries in order to have stable flight. In order to achieve a stable CG, the battery had to be mounted as close to the leading edge as possible.
In the pictures, this plane looks sloppy (duct tape everywhere), but this is partly because all the pictures were taken after a day of flying and crashing. I also found that duct tape sticks to the foam very well, but it is too heavy to use on radio controlled airplanes. Clear packing tape is lighter, but it doesn't stick very well to the foam.
Crash - Plane flew out of range (780 ft. from me) and crashed in someone's backyard. The Micro Futaba receiver I was using has a range of 650 ft (it's designed for indoor use). I distributed flyers door to door offering a $20 reward and the next day I found my plane. The battery was dead, but the motor, ESC, receiver and servos were fine.
I used a homemade hot wire foam cutter to cut the foam wing. I chose to use R20 insulation foam, which can be purchased from Home Depot because it is significantly less expensive than balsa, and it can be cut with a hot wire.
The foam is not covered with anything, but there is a piece of sheet metal on the bottom, which wraps around the leading edge of the wing. This was added on because after the first few crashes, the front of the wing broke off and I needed something to hold the battery in place.
Spar - Two 1/4" x 1/8" pieces of spruce; run along the length of the wing
Elevons - Cut back of airfoil and beveled 45 degrees
Similar to - EPP Assassin [found online]
I used an online tool to find out where the Centre of Gravity (CG) should be (http://fwcg.3dzone.dk). Through experimentation, I found that this online tool is fairly accurate - a good starting point for experimentation. The CG should be within the boundaries in order to have stable flight. In order to achieve a stable CG, the battery had to be mounted as close to the leading edge as possible.
In the pictures, this plane looks sloppy (duct tape everywhere), but this is partly because all the pictures were taken after a day of flying and crashing. I also found that duct tape sticks to the foam very well, but it is too heavy to use on radio controlled airplanes. Clear packing tape is lighter, but it doesn't stick very well to the foam.
Crash - Plane flew out of range (780 ft. from me) and crashed in someone's backyard. The Micro Futaba receiver I was using has a range of 650 ft (it's designed for indoor use). I distributed flyers door to door offering a $20 reward and the next day I found my plane. The battery was dead, but the motor, ESC, receiver and servos were fine.
Through this experience, I improved my design and construction skills, which now allows me to design and build better flying wings.