What Makes a Good Glider Louie Turek aerospace_pilot@yahoo.com

What Makes a Good Glider

Louie Turekaerospace_pilot@yahoo.com

Fundamentals

• Wing Shape

• The Importance of a Tail

• Balance!

Wing Shape

Leading edge

Trailing edge

Chord

Long, thin wings- Good for gliders

Smooth airfoil shape is essential for good gliding performance

Wings must be strong enough

Wing Structure

Foam wing

Skeleton with covering

Wing Structure

Folded material with spar inside

Wing sweep- Bad idea for gliders

Dihedral- Helps with Stability

The Tail is VERY Important!

No Tail Means No Stability

Proper Sizing and Balance-The rule of fingers

Horizontal tail- 5X smaller than wing area

Vertical tail- 10X smaller than wing area

Canards, efficient but possibly unstable

Flying wing, more efficient but almost guaranteed unstable

Forces on a Glider

Weight

Thrust??????

Drag

Lift

Gravity is source of thrust

Balance – Center of Gravity

Short

Long

Balance Point-Center of Gravity

Wing ~ ¼ back along body

Body length ~ same as wingspan

Wrap Up• Wing Shape- smooth and broad,

but strong enough

• Tail surfaces- Far back and rule of fingers, lightweight tail

• Balance!

Wrap Up• Check that glider balances

• Use ballast to correct flight path

• Practice throwing technique

Rules Review• Minimum 24 inch wingspan, maximum 4”x4” body

• No wheels allowed, no kit materials of any kind allowed, no paper airplanes

• Must carry 16 marbles, sealed in place in sandwich bag

• Weight between 6 and 10 ounces (including 2.1 ounces of marbles)

• Total of 4 flights, score is total distance glided

• If the glider breaks apart, score reduced 25%

Suggestions/Things to Think About• Hobby/craft stores for balsa wood

• Hobby stores have lead edge surface balsa

• Marbles available at craft stores as well

• Small balsa gliders for practice

• Don’t waste material on unneeded things

• Don’t bother with slot construction

Good luck!

Louie Turekaerospace_pilot@yahoo.com