CeAnn Chalkerceann@chalker.org

Ballast

Fuselage Horizontal Stabilizer/StabWing

Launch Hook

Vertical StabilizerFinRudder

Chord

Span

* Glider(s) up to 2 at Competition* Flight Log

* Very similar to AMA event “Standard Catapult Launch Glider”

*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

*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

*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

•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!

*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

*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

*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

*Winner – *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

*Anticipate building many gliders throughout the year

*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

*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

*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

*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

* Building Tools, must have* 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)

* Building Materials

*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)

*Necessary-*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

* Plans -* 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!!!

* 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!!

*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

*Use Carbon Fiber for reinforcement

*Strong in Tension Only!

*Fuselage Ideal Spot

*Foam Meat Trays

*Light Wings

*Center of Gravity Critical

* 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.

*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

*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

*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

*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!!!

*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

*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

*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 http://www.soinc.org/elastic_launched_glider_c

* Start here first. http://www.amaglider.comwas 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

• Good Starting point:

• http://www.soinc.org/elastic_launched_glider_c

• LOTS of information: • legacy.amaglider.com

• www.indoorduration.com

• Forums: www.scioly.org

• Supplies - www.freedomflightmodels.com

•Rubber: www.faimodelsupply.com• (buy 3/32” stock unless you have a rubber stripper)

•Various tools: www.indoorspecialties.com

•Bulk Balsa:

•www.nationalbalsa.com

•www.balsawoodinc.com