2016-17 Matthew Chalker chalker7@gmail.com Wright Stuff – B 2016-17 Matthew Chalker chalker7@gmail.com

Disclaimer This presentation was prepared using draft rules. There may be some changes in the final copy of the rules. The rules which will be in the published Rules Manual will be the official rules.

What is Wright Stuff? Students will design, construct, and TEST free flight rubber-powered monoplanes to achieve maximum time aloft.

Wright Stuff Basics Allowed 2 Ultra light aircraft built and tested prior to competition Flown indoors Timed for duration aloft No Impound Aircraft to be labeled Must be a monoplane with single two-bladed propeller assembly Must prepare a flight log of test flights

Construction Materials Any materials except Boron Filaments may be used in construction of the airplane Can be made from published plans, commercial kits, and or student’s design Kits must not have pre-glued joints or pre-covered surfaces

Building Specifications 7.5 grams - minimum total mass of plane (without rubber motor) 45.0 cm - max horizontal projected wing span 11.0 cm - maximum wing chord 22.5 cm - max horizontal projected stabilizer span 8.5 cm - maximum stabilizer chord

Power Specifications Rubber Motor Plane powered by wound rubber band 1.5 grams maximum mass (includes O-rings)

Propeller Single two-bladed propeller 14.0 cm - Maximum diameter Commercially made OR Propeller Assembly may be built by competitors Variable-pitch propellers with mechanisms to actively change the blade diameter or angle are not allowed!

Launching & Labeling Plane is launched from the hand Plane must be labeled for identification

Visibility At least one vertical surface must be covered in an opaque, non-white material

Flight Log 6 parameters for at least 10 previous flights prior to competition 3 required parameters Motor size before windup Winds on the motor at launch Flight time 3 Additional parameter examples Turns remaining at landing Estimated peak flight height Estimated flight path diameter Torque at launch

Competition 8 minutes to launch their 2nd flight after their 1st flight (trim or official) begins Motors impounded after check-in, are available only for official flights Teams must declare before any launches during the 8 minutes if it is an official flight or a trim flight. If not declared any launch will be considered official.

Competition During 8 minute Flight Period teams may: Make adjustments & repairs Launch trim flights Qualify additional motors Timing will be to the precision of the devices used

Competition - Timing Timing Begins when the airplane leaves the competitor’s hand Timing Ends when any part of plane touches the ground (this includes pieces falling off) or the plane comes to rest on any obstructions (even if prop continues to rotate)

Competition Competitors only allowed in testing/flight area No outside assistance, materials, or communication allowed once competitors enter the cordoned off competition area to trim, practice, or compete No Steering allowed

Competition Test flights allowed throughout competition at the discretion of the Event Supervisor, ending at least by the last 30 mins. of the tournament Test flights will yield to official flights Multiple aircraft may test fly at once

Scoring Winner is team with the longest flight time for any single flight Ties broken by second flight time

Bonus – Wing Covering 10% of the flight time will be added for planes that have a colored panel on the wing that is at least the length of the wing chord and between at least 2 wing ribs.

Deductions & Violations Flight Log Incomplete flight logs will have 10% of the flight time deducted from each flight No flight log will have 30% of the flight time deducted from each flight Rule Violations without a specific penalty will be ranked after all teams that do not violate the rules

Critical Takeaways - build the plane as light as the rules allow WARNING: these planes are fragile, you will break it, others will break it even easier if you let them, sometimes you break it intentionally, GET OVER IT! Rule 1 - build the plane as light as the rules allow Rule 2 - make sure your plane doesn’t weigh too much Rule 3 - go back and read rules one and two! Rule 4 - build accurately, spend time preparing materials, making jigs & patterns, etc. Build fast. Rule 5 - take LOTS of data, which means lots and lots of flying!

Building Tools A flat building board, able to take pins Wax paper or packing tape to cover plans Lots of Razor Blades or Sharp knives with lots of spare blades A good metal edge rule/straight edge Lots of pins & scrap balsa blocks A good scale accurate to 0.01 gm, cheap (less than $20) Wire cutters and pliers

Building Tools – Nice to Have Precision micro super glue applicator, two pins stuck through a stick at an angle to come together at their ends Balsa stripper A six inch piece of 0.063 music wire Mat board or writing tablet backs, not poster board, for jigs ¼ inch thick balsa sheets for jigs Misc square blocks for jigs

Building Materials KITS - easy way to get everything to build 1 or 2 planes, costly OR… Balsa - 1/32, 1/16, and ¼ inch thick sheets, or suitable width sticks, light to medium density Covering - indoor mylar, tissue, produce plastic bags Glue - Superglue (also called: cyanoacrylate or CA) or balsa cement If using CA, instant setter – accelerator Music Wire - 0.020 diameter Props Prop hanger Clay

Flying Items - Necessary Rubber - FAI TAN Sport or Super Sport, various thicknesses - 3/32 is a good starting point O-rings – Size #60 - ¼”O.D. x 1/8”I.D. x 1/16” Or Sliced from Teflon tubes Winder Stop watch, NOT your cell phone, you’ll get DQ’d Your flight LOG and a pen/pencil! A good carrying/storage box

Flying Items – Nice to Have Stand to hold the plane An anchor to wind motors - off the plane Torque Meter Repair Kit – CA glue Accelerator Straight edge Spare covering Spare balsa

Building Techniques – Cutting Ribs

Building Techniques – Wing & Stabilizer Pin spars to plan or jig. DON’T pin through balsa! Dry fit ribs in position Check rib position for accuracy Glue with CA using microapplicator Let dry or apply accelerator. Remove from building board

Building Techniques – Covering the Wing Cut covering to size and lay on flat surface Any spray glue works Once you drop the wing on the paper, don’t try to move it.

Building Techniques – Wing covering cont’d Smooth down one edge Roll down ribs Trim using a fresh, sharp razor Smooth down second edge

Building Techniques – Dihedral & Adding Wash Cut halfway through right wing Crack at cut, prop wing tip up Same process for left wing washin. Cut at last rib and center of leading edge, prop up leading edge, glue at 3 crack points. Use CA glue at 2 crack points

Building Techniques – Motor Stick, Thrust Bearing, & Rear Hook Make a slit on lower side of motor stick for Thrust Bearing Insert Thrust Bearing in slit making sure Prop shaft is parallel to motor stick. Glue with CA. Insert Rear Hook through tail of Motor Stick adding a spacer of wood.

Building Techniques – Tissue Tubes Use Ambroid or Duco Cement, NOT CA Glue

Building Techniques – Finding Center of Gravity Center of Gravity is the Balancing Point Assemble w/fuselage, stabilizer, propeller, & motor Do not add the wing yet Balance on thin piece of wood or your finger Mark CG (Balance Point) on fuselage

Building Techniques – Adding Paper Tubes Glue front Paper Tube in front of the Center of Gravity mark approximately 1/3 of the distance of the Wing Chord on the right side of the fuselage. Measure the distance of your Wing Chord and glue the rear Paper Tube that distance from the front Paper Tube. Make sure the Paper Tubes and Wing Posts are Perpendicular to the Fuselage and Parallel to each other. Do not glue the posts into the paper tubes.

Building Techniques – Wing Assembly Raise Leading Edge higher than Trailing Edge Adjust after trim flights

Building Techniques – Checking The Stabilizer is parallel to the table The Left side of the Wing is longer and dipped lower than the Right side of the Wing (tilt compared to Stabilizer) This creates the turn in flight Leading Edge Wash-in - vertical difference in Leading Edge to Trailing Edge (gives lift) Trailing Edge

Flying Tips Rubber Motor Lube your motors WIND THEM! BREAK A MOTOR OR TWO to know when it breaks! Pre Flight (develop a checklist, use it every flight) Assemble plane Check settings Left wing should have leading edge a little high (wash-in), right wing flat Stabilizer should be flat & parallel to ground Prop should point SLIGHTLY down and left Check for anything broken, fix it. Test fly with motor but no winds, it should glide gently to floor. Recheck settings

Flying Tips – Winding First Flights – Wind at partial winds Wind off the plane using a hook, put the knot by the hook Stretch 3-4 times length, start winding stretched, about 500 to 600 turns start coming in to end at motor stick length with 1000 plus turns Transfer the motor to the plane Have one partner hold the plane, lock the propeller and present it to the winding partner, watch the tail! Winding partner, without touching plane (much) take motor off winder, put it on prop hook. Then take other end of motor off anchor and put it on tail hook. Knot should be on the tail hook.

Flying Tips– Launch Launch at shoulder height when you can consistently hit the ceiling, launch close to floor Give the plane only a GENTLE push in direction of flight Launch the plane level Time and observe flight Record all data including behavior

Behaviors & Fixes Note – Change only One Thing at a Time and in Small Amounts!!! It flies pretty good. Rare, but it happens  Start changing factors small amounts, one at a time to improve times COLLECT DATA for future reference It flies OK, but just doesn’t want to climb. Try more winds Try a fatter motor Try a lower pitch prop Add a little left wing wash-in

Behaviors & Fixes Stalling - It tries to fly, but keeps repeating nose up, slows down, drops nose, and repeats Move the cg forward with ballast Lower the leading edge of the wing Raise the trailing edge It dives quickly to floor - try one of the following: Raise the leading edge of the wing Raise the trailing edge of the stab Move the cg back with ballast Make sure you didn’t wind the motor backwards!! It climbs strongly, nose constantly pointing up until the plane hangs on the prop than stalls hard Add some down thrust to the prop hanger

Resources & Supplies Resources Supplies on line Indoornewsandviews.com indoorduration.com Yahoo Groups – Wright Stuff SO website http://www.hippocketaeronautics.com/hpa_forum/index.php Supplies on line FAImodelsupply.com

Internet Links http://www.soinc.org/sites/default/files/uploaded_files/ScienceOlympiad5.0.pdf http://scioly.org/wiki/index.php/Wright_Stuff http://freeflight.org/education/science_olympiad/ https://bsmsscienceolympiad.wikispaces.com/Wright+Stuff https://www.scribd.com/doc/36303184/Penny-Plane-by-John-Barker http://freeflight.org/jlf/beginners_corner/whammy_series/double_whammy/dw_article.pdf