Semaphore Challenge
Sea Cadets - Bonus Activity
Semaphore is a visual signalling procedure that dates back, in its present form, to the 18th century. The two hand flags are red and yellow in colour, split diagonally, with the red side opposite the handle. Both flags are used in combination to form letters and numbers. Since the receiver must be able to clearly see the sender, this type of communication is used during daylight over short distances.
Semaphore signalling allows for rapid transmission of characters between stations. Since there is always the possibility of someone intercepting an electronic transmission, the simplicity of using flags to communicate is very appealing.
Step #1 - Create semaphore flags
The objective of this activity is to have the cadets create flags to use in semaphore activities.
RESOURCES
• Blank paper.
• Flag diagram (Attachment A).
• Scissors.
• Pencil crayons or markers.
ACTIVITY INSTRUCTIONS
1. Have the cadets cut out squares of paper.
2. Have them fold the paper in half diagonally from bottom left corner to top right corner to create the flag
pattern.
3. Have the cadets draw a line on the fold.
4. Have the cadets colour the top left portion of the flag red, and the bottom right portion yellow.
Step #2 - Introduction to semaphore code
Use the checklist on the semaphore code and practice recreating the letters of the alphabet.
Step #3 - Complete the Semaphore Challenge
Using the Flip Grid application, film yourself sending the following word using the semaphore code.
Send the following word : COVID-19