Here is a picture of a Bamboo Squirrel from Brazil!
I received this from the Engineering Department of Universidade Federal de Uberlândia.
The Squirrel is their final exam first-year Aeronautical Engineering students.
Here is a cool alternate version of the Squirrel. It uses copy paper instead of tissue paper. It was prepared by Brett Herrick from the First Flights program.
The Copy Paper Squirrel is a low cost, rubber powered airplane that flies well and is easier to build than the Delta Dart. The Copy Paper Squirrel is easier to build than the Delta Dart because all of the balsa sticks are cut at a ninety degree angle and can be pre-cut to specified lengths so that no fitting of the balsa sticks is required. The Copy Paper Squirrel also has the advantage that the position of the wing on the fuselage can be adjusted (i.e. the wing is held to fuselage with a rubber band) making it easier to adjust it to fly well. I use the Copy Paper Squirrel project as the project that follows mastering making the balsa glider projects but to be built prior to making the Delta Dart project.
The Copy Paper Squirrel was developed for use with the First Flights classes. The biggest difference between the Copy Paper Squirrel and the Squirrel is that it is built on plans rather than on top of tissue paper (i.e. this makes it easier for younger kids to build it). The Squirrel was designed by Darcy Whyte and he has graciously given his permission to use the material that he has developed for the Squirrel. His website describing the Squirrel is http://www.rubber-power.com/
Copy Paper Squirrel Bill Of Materials
To build the Copy Paper Squirrel one needs to purchase the materials listed on the Bill of Materials and print out the plans (i.e. the plans need to printed full size on 11” x 17” paper. If the plans are printed out other than full size the precut balsa strips will not fit properly). For the materials that may be difficult to purchase locally, I have listed the sources that I have used below:
Balsa Strip Description Quantity Needed
——————————- ———————-
1/8” x 3/8” x 12” 1
1/8” x 1/8” x 4” 1
1/16” x 3/16” x 2” 7
1/16” x 3/16” x 6” 1
1/16” x 3/16” x 12” 2
1/16” x 1/8” x 12” 1
Regarding materials that can be purchased locally:
To build the Squirrel I recommend the following supplies and tools:
Building the Fuselage
On the Motor Stick, locate the wing position marks and mark them on the Motor Stick with a gel pen.
Copy Paper Squirrel – Fuselage parts
The Vertical Fin is to be located to the Motor Stick as shown on the plans. Namely, the back of the Vertical Fin is to be flush with back edge of the Motor Stick and the bottom of the Vertical Fin is to be flush or above the bottom of the Motor Stick. To attach the Vertical Fin to the Motor Stick, glue stick glue is to applied to rear 1 – 2” of the Motor Stick, tacky glue is to be applied with a toothpick to the front of the Vertical Fin (i.e. balsa stick) where it will touch the Motor Stick and then press in place.
Copy Paper Squirrel – Fuselage completed
Copy Paper Squirrel – Fuselage upside down 2
Building the Wing
Cut the paper Wing pattern from the plans by cutting on the dark line at its perimeter.
Copy Paper Squirrel – Folded wing pattern
1.) The 1/16” x 3/16” x 12” balsa stick on the leading edge
2.) The three 1/16” x 3/16” x 2” balsa sticks in the middle of the wing
3.) The 1/16” x 3/16” x 12” balsa stick on the trailing edge of the wing
4.) The two 1/16” x 3/16” x 2” balsa sticks in the wing tips
5.) The 1/16” x 1/8” x 12” balsa stick that forms the top of the wing
Copy Paper Squirrel – Wing with balsa sticks
To cover the top of the wing, crease the top of the Wing over the leading edge of the wing, apply stick glue to the top of the trailing edge of the wing and then pull the wing top over the top of the wing. The paper is to be pulled tight with the edge of the paper parallel with the rear edge of the trailing edge balsa stick (i.e. the more even the wing top covering lines up with the trailing edge of the wing the less twist the wing will have and the better this model will fly). Then press down on the paper to make it adhere to the balsa stick.
Assembly of the Copy Paper Squirrel
Assemble the wing on to the Motor Stick. Slip a # 10 rubber band over the nose of the Motor Stick. Place the wing with the leading edge facing forward on the top of the Motor Stick near the front of the Motor Stick. Pull the rubber band over the top of the wing and around the nose of the Motor Stick. Position the wing so that wing is in the middle of the marks on the top of Motor Stick and the marks of the top of the wing are centered on Motor Stick.
Copy Paper Squirrel – Finished project with tan background
Flying of the Copy Paper Squirrel
1) Adjust the position of the wing on the Motor Stick so that when on puts a finger under the middle of each wing tip that it balances.
2) Hand wind the propeller 50 turns for the first flight.
3) To launch the Copy Paper Squirrel hold the model between your thumb and index finger at the middle of the Motor Stick. Let the propeller go and gently toss the model horizontally.
4) If it dives to the ground, then move the wing forward. If it goes high and stalls, slide the wing back. The reference marks on the top of the Motor Stick are so that one can tell how far forward or rearward the wing is.
5) To keep it from turning, slide the wing out horizontally in the direction that it turns. The reference mark on the middle of the wing is so that one can tell how far the wing is shifted.
6) When it lands, the wing may move. If so, it will be necessary to reposition the wings relative to the reference marks again.
7) As the Copy Paper Squirrel gets adjusted, increase the number of winds on the propeller by 50.
8) It is better to let the model land itself than try to catch it out of the air (i.e. you are likely to damage it if you try to catch it).
Here’s a quote from Hip Pocket Aeronautics.
I’d like to point out the inherent stability of Darcy Whyte’s (Canada) popular SQUIRREL design. It has NO DIHEDRAL, no pylon, but has vertical UPRIGHT wing tip plates. In analysis when the wing banks an impending lateral SIDESLIP is instantly countered by a roll moment from the UPRIGHT TIP PLATES. Therefore an impending spiral is halted and the wing is brought back to horizontal. This is STABILITY.
The proof might be to try a wing with an UPSIDE DOWN wing tip plates. I fear this will increase the spiral tendency and a CRASH. I’d rather not try it. –Ding