1. Elastic Launch Glider- B 2015-16
CeAnn Chalker

2. Parts of a Glider Wing Horizontal Stabilizer/Stab Fuselage Ballast
Vertical Stabilizer
Fin
Rudder
Launch
Hook
Parts of a Glider

3. Span
Parts of a Glider
Chord

4. Two Overall Components of Event
Glider(s) up to 2 at Competition
Flight Log
Very similar to AMA event “Standard Catapult Launch Glider”

5. Construction Parameters Dimensions
Maximum Wingspan – 30.0 cm
Minimum Glider length – 32.0 cm
Minimum of 3.5 grams
Maximum of 10.0 grams
Nose must be blunt
When inserted into a lip balm cap does not touch the inside end of the cap
depth~15.7 mm
diameter~13.7 mm

6. Construction Parameters
Constructed of only wood, foam, paper, plastic film, carbon fiber, tape, thread, and glue
Ballast may be any malleable, non-metallic substance
May be constructed from:
Published Plans
Student Designs
Commercial Kits
Kits MUST not contain any pre-glued joints or pre- covered surfaces
Gliders must be labeled

7. Construction Parameters Launching Parts
Launch Apparatus (excluding elastic)
MUST be used
MUST be less than 1 meter long in any orientation at launch
MUST be a safe configuration
MUST be operated by a Single Competitor
May be constructed by the competitors or acquired completely assembled
Elastic
MUST be non-metallic
MUST be In contact with the glider throughout launch

8. Launch Handles

9. Flight Log Minimum of 10 entries Minimum of 4 data points
Estimated Peak height
Length of Elastic (relaxed)
Flight Time
Any one other (more are fine)
10% deduction for incomplete Flight Log
30% for no Flight Log
Most important part of practice and competition!

10. Competition
Competitors MUST wear eye protection at all time when in the Competition Area
Launch MUST be aimed only towards the ceiling
Flight Period for Official Flights – 5 minutes
Starts with 1st Official Flight
Official Flights – up to 5 using 1 or 2 Gliders
All flights within a Team’s Flight Period are official unless declared a trim flight prior to launch.
Steering is not allowed

11. Competition (Inspection)
Official Inspection – Immediately prior to 5 official flights teams must present -
Glider(s)
Launch Apparatus(s)
Flight Log
Construction violations for Gliders and/or Launch Apparatus will cause the team to be ranked behind all other teams
Event Supervisors may request a re-inspection

12. Timing Start – when Glider leaves the Launch Apparatus Stops -
Any part of the Glider touches the floor (including pieces that break off)
When Glider stops moving due to an obstruction

13. Scoring Winner – Ties - Penalties –
Highest sum of the team’s 3 longest official flight times aloft (minus Penalties)
Ties -
broken by longest non-scored official flight
Penalties –
10% flight time deduction for incomplete log
30% deduction for none (off of each flight)
Construction & Competition violations for a Glider are ranked below all other teams

14. Construction - General
Anticipate building many gliders throughout the year

15. What is Elastic Launched Gliders About?
It’s not about designing a glider
It’s actually about collecting data and evaluating it to optimize a complex system
Unless you can build a glider that flies, you can’t start data collection so it is obviously required
Gliders is one of the 3 flying events in rotation for this purpose

16. Glider “Secrets” All about Sink Rate Seconds/Feet of descent
~1 sec/foot is good
Combination of weight and lift
Weight – Wood Selection, Build Quality
Lift – Trim, Build Quality, Design
Height achieved critical
Transition to Glide is important
Design will change based on ceiling height

17. Construction - General
Priorities
1 - Build quality/trueness/straightness
2 - Strength
3 - Weight (as close to 3.5 grams as possible)
4 -(and a distant number 4!!!) Design

18. Where Do We Start? Choose a design –
(you have to start somewhere)
Gather and prepare materials
Construct the Glider
Make wing, sand carefully to shape
Make stabilizers
Make fuselage
Assemble
Trim for Performance and Repeatability

19. Tools and Supplies Building Tools, must have Building Tools, Helpful
A flat cutting surface (Use old plywood)
Razor knife ($2 Hobby Lobby)
A metal edge rule/straight edge ($2)
A scale accurate to 0.1 gm cheap mini pocket electronic ones available on the net (less than $15 from Amazon or Old Will Knott)
Building Tools, Helpful
Balsa Stripper (Master Airscrew Balsa Stripper or Windsor Balsa Stripper less than $10)

20. Building Materials (minimum)
A complete kit, easy way to get everything to build 1 or 2 gliders – COSTLY OR
Balsa, 1/32 and 1/16 sheets
Glue, Superglue (also called: cyanoacrylate or CA) or balsa cement
If using CA, instant setter (accelerator)

21. Flying Materials Necessary- Helpful - Catapult apparatus Rubber
Stop watch, NOT your cell phone, you’ll get DQ’d
Your flight LOG and a pen/pencil!
A good carrying/storage box
Helpful -
Glider Stand –
Something to hold the glider, remember, they break, often when they fall off a table
Repair Kit
CA, setter, knife, spare covering, spare balsa

22. Design – Select a Plan Plans - Two key elements -
Available on the internet
Come with kits
Two key elements -
Drawing
with dimensions and all parts
A bill of materials
often missing, you probably will have to make it yourself
Wherever you get your plans - Make sure they comply with the Current SO rules or adjust accordingly!!!

23. All Plans are not to SO Specs!
If you find designs online most will be AMA designs.
There are a lot of ‘GOOD’ designs to AMA rules. BUT, AMA rules AREN’T SO rules.
We don’t know that AMA designs won’t turn out best, but…
Remember, the purpose is to test, collect data and adjust!!

24. Select Plans – The Drawing

25. Material Selection Balsa Selection:
Wood selection is CRITICAL, straight, correct weight, stiff, etc.
If possible visit the hobby shop and WEIGH EACH SHEET !!!
Specialty wood is not required with the 3.5 g minimum.
Select straight sheets for your components to match plan.
Have glue, pins, scrap blocks on hand

26. Construction - Details
Use Carbon Fiber for reinforcement
Strong in Tension Only!
Fuselage Ideal Spot
Foam Meat Trays
Light Wings
Center of Gravity Critical

27. Trimming for Performance & Repeatability
Plan LOTS of Practice Time –
I can show you how to build a Glider, but without practice and data collection you won’t be able to fly it!
Data Collection –
This event is PRIMARILY about data collection and evaluation. Minimal flight logs pass the requirement, but miss the point. Teams with logs do better.

28. Trimming – Step #1 Do several hand glides
It should glide in the correct direction without diving or stalling.
Make a couple of level 25% power catapult launches to determine the glider direction and make sure the model doesn’t want to nose dive or go into a loop.
These must be corrected to a level flight first
Record data

29. Trimming – Step #2 Use Launch Apparatus and add some Elevation
Use 25% Power
Do NOT aim straight up like you are shooting an arrow at the moon.
This model needs to glide, and to do that it needs to transition from fast catapult to slow glide
Getting the transition to work correctly is the hard part
Record Data

30. Trimming – Step #3 Launch at Half Power
Start with about 45º bank and 30º elevation
The model should arc up and then go into the correct glide
The elevator is your most powerful control and then rudder
Record Data

31. Trimming – Step #4 Increase Launch Power to 80%, if OK then 100%
You may need to adjust the launch angle.
As you approach maximum warp speed things happen much faster
a trim that works at 50% power may not cope with higher speeds
the trim becomes more critical and needs to be refined in smaller steps
If it is now too loopy you will need down elevator, perhaps a touch of rudder
Be accurate and consistent on the launch angle
Record DATA!!!

32. Flying - Basics
Attach one end of elastic to Launch Apparatus and to Glider
Pull back the Glider to extend the elastic
Check the ceiling
Make sure you launch aiming at any point on the ceiling
Let Go of Glider!
Record Data!
Be prepared for repairs
Avoid grabbing a flying Glider from the air

33. Flying – Adjusting Basics
Trim for lowest sink rate
Stall – Too much lift
Wave pattern on descent
Dive – Too little lift
Goes down to fast
Adjust Center of Gravity (CG) with Ballast
Adjust Incidence by bending wood
Increased Wing Incidence increases lift (leading edge of wing higher than trailing edge)
Decreased Stab Incidence increases wing incidence

34. Required Flight Log Sample

36. Resources Where to find help?
Everything I cover here and more is on the internet somewhere, the National SO page is a good starting point
Start here first. written by one of the best practioners of gliders, study, read and understand this site.
Check you local AMA clubs, especially those focusing on free flight

37. Links LOTS of information: Forums: www.scioly.org
Good Starting point:
LOTS of information:
legacy.amaglider.com
Forums:
Supplies -
Rubber:
(buy 3/32” stock unless you have a rubber stripper)
Various tools:
Bulk Balsa: