Unmanned Aircraft Systems 

Activity Two: Propelling the Payload With Electric Propulsion 

Educator Notes 

Learning Objectives 

Students will 

• Investigate the impact of varying mass on the average speed of a propeller car (either of the designs below). 

or 

Suggested Pacing 

45 to 90 minutes 

Investigation Overview 

Students will explore the compromises engineers have to make when designing an electric vehicle 

with batteries. Specifically, students will use a propeller car (premade or by design) to investigate the 

effect of varying mass on average speed. This investigation will highlight the tradeoff of higher 

capacity batteries being heavier. 

National STEM Standards 

 

 

 

 

Science and Engineering (NGSS) 

Disciplinary Core Ideas Crosscutting Concepts 

• MS-PS2-2 Motion and Stability: Forces and Interactions: Plan an investigation to provide • Stability and Change: Explanations of stability and change in natural or designed systems evidence that the change in an object’s motion depends on the sum of the forces on the can be constructed by examining the changes over time and forces at different scales. object and the mass of the object. 

• MS-PS3-1 Energy: Construct and interpret graphical displays of data to describe the 

relationships of kinetic energy to the mass of an object and to the speed of an object. 

Technology (ISTE) 

Standards for Students 

• Knowledge Constructor: Students critically curate a variety of resources using digital tools 

to construct knowledge, produce creative artifacts, and make meaningful learning 

experiences for themselves and others. 

Standards for Students (continued) 

• Computational Thinker: Students develop and employ strategies for understanding and 

solving problems in ways that leverage the power of technological methods to develop and 

test solutions. 

Mathematics (CCSS) 

Mathematical Practices 

• MP.2: Reason abstractly and quantitatively. 

Content Standards 

• 6.EE.A.2: Write, read, and evaluate expressions in which letters stand for numbers. 

• 7.EE.B.3: Solve multistep real-life and mathematical problems posed with positive and 

negative rational numbers in any form, using tools strategically. Apply properties of 

operations to calculate with numbers in any form; convert between forms as appropriate. 

and assess the reasonableness of answers using mental computation and estimation 

strategies. 

Content Standards (continued) 

• 7.EE.B.4: Use variables to represent quantities in a real-world or mathematical problem, 

and construct simple equations and inequalities to solve problems by reasoning about the 

quantities. 

• 8.F.A.3: Interpret the equation y = mx + b as defining a linear function whose graph is a 

straight line; give examples of functions that are not linear. 

Investigation Preparation 

• Read the introduction and background information, Educator Notes, and Student Handout to become familiar with the activity. 

• Determine teams and roles prior to the investigation. See team role suggestions in the front of this educator guide. 

• Prepare materials ahead of time in the materials area for team assembly. 

• Make copies ahead of time of the Student Handout, Propeller Car Instructions (Appendix C), and optional Basic Propeller 

Template (Appendix C). 

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Unmanned Aircraft Systems 

Materials (per team unless noted) 

 1 balance (one per whole group) 

 1 ruler or measurement tape 

 1 timer 

 Various items representing mass (washers, coins, etc.) 

Tip: Pennies weigh approximately 2.5 to 3.1 grams for an easy unit of measure. 

 Graph paper 

 Calculators 

Building Supplies for Propeller Car 

 See Propeller Car Instructions in Appendix C for list of materials. 

Note: For data comparison purposes, each car should be made with the same materials 

to eliminate extra variables. 

Safety 

Review all safety tips before building the propeller car. Adult supervision is required for 

building and testing the propeller car. 

Introduce the Investigation 

• Before providing information to students, begin with a graphic organizer and simply write 

the word “drone.” See how much information students already know and what they want 

to learn. Return to the graphic organizer at the conclusion of the investigation to follow up 

with students about what was learned through the activity. 

• Show one or both of these introductory videos: 

– What Is AAM? https://youtu.be/Vu1VWEvgd24 

– NASA LEAPTech: Distributed Electrical Propulsion. https://youtu.be/hhL2-Lykl9s 

• Explain the details of the investigation, including criteria and constraints. 

Criteria Constraints 

Students may utilize a commercially available propeller 

car or use the provided instructions to build a motorized 

or rubberband-powered propeller car. 

Students may not deviate from the propeller car 

design or use a different design than other teams. 

Students must design an investigation that 

demonstrates how mass affects the speed of a 

propeller car. 

Facilitate the Investigation 

Pose Question 

• After watching the introductory videos, ask students guiding questions such as these: 

– What are some challenges of electric propulsion for unmanned aircraft systems 

(UAS)? 

– In what ways are electric propulsion and propulsion on traditional aircraft similar or 

different? 

– Why is the battery such an important part of a UAS? 

– Is a bigger battery always better? What are the benefits and drawbacks of a bigger 

battery? 

Brain Booster 

We often confuse the terms 

“mass” and “weight” and use 

them interchangeably even 

though they have very different 

meanings. Mass does not 

change whether it is measured 

on Earth, the International Space 

Station, or Mars. Weight can 

change depending upon the 

gravitational pull, such as on the 

Moon, where weight is reduced 

to one-sixth that of on Earth. 

Follow the link below and see how 

much you weigh on the other 

planets in our solar system. 

Learn more: 

https://www.nasa.gov/specials/ki 

dsclub/games/astro-matic3000/index.html 

On Location 

Katherine Johnson worked for 

NASA from 1953 to 1986 as a 

mathematician. She made her 

mark in history at a time when 

women and African Americans 

were regularly marginalized. 

NASA’s Langley Research 

Center has named a 40,000-

square-foot Computational 

Research Facility in her honor. 

Johnson calculated the trajectory 

of the first American in space in 

1961. She verified the 

calculations of the 1962 launch 

into orbit and the calculation for 

the Apollo 11 trajectory to the 

Moon. Johnson has been 

recognized throughout the years, 

and Hollywood told Johnson’s 

story in the film “Hidden Figures.” 

Learn more: 

https://www.nasa.gov/feature/lan 

gley/computational-facilitynamed-in-tribute-to-nasa-langleymath-master-katherine-johnson 

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Unmanned Aircraft Systems 

• Explain to students that they will be investigating the tradeoffs between the capacity of a battery and its mass with respect to how 

that might affect the speed of a UAV. The following diagram captures the essence of the problem. 

The D battery can store more power than the AA battery but weighs a lot more. 

• If students do not immediately grasp why the illustrated tradeoff is not always worthwhile, show them a propeller car with a battery 

that is so big the car cannot possibly move and might even be crushed. 

There is such a thing as “too much power.” 

Develop Hypothesis 

Electric propulsion, while beneficial to our overall environmental impact, does present challenges for scientists and researchers. One 

of the main challenges is that batteries are heavy, and the heavier the object, the greater the force that is needed to move the object, 

according to Newton’s second law. 

• Teams will use a propeller car (representing a UAV) to investigate how mass (representing batteries) can affect average speed. 

Students are free to choose the object they will use to increase the mass added to the car and the increments by which they will 

increase the mass. 

• If students are having difficulty formulating a testable hypothesis, provide them with the following prompt: “If mass is __________, 

then the average speed of the propeller car will _________________________.” 

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Unmanned Aircraft Systems 

Plan Investigation 

• Teams will construct an electric motor propeller car or a rubberband-powered propeller car to test their hypothesis. 

Note: As a time-saving alternative, educators may choose to construct or purchase enough commercial propellers for everyone 

in advance. However, if a commercial propeller is not available, students may use the Basic Propeller Template in Appendix C 

to build their propeller. 

• Teams will brainstorm suitable objects to use for mass and develop a testable hypothesis along with a plan for investigation. 

• Once the team has a working propeller car, they will need to prepare for data collection. A sample data table is provided here: 

Amount of mass added 

to test car, g 

Payload 

Time to travel length of course, s Average speed, 

m/s Test 

1 

Test 

2 

Test 

3 

Average 

time 

0 5 5 5 5 2 m/5 s = 0.4 m/s 

5 7 10 10 9 2 m/9 s = 0.22 m/s 

• Students should pick a standard course length for all of their tests. A 2-m course length is typically long enough, but longer or 

shorter courses are fine if there is enough space to test safely. The starting and ending points of the course should be clearly 

marked. Student-made cars may not always travel in a straight line, so the finish line may need to be a semicircle centered on 

the starting point. 

• In order to mitigate random error, students will be using the average (mean) time of three tests per chosen mass. 

• To find the average speed, take the length of the course and divide it by the seconds taken on average; for example, if a propeller 

car travels 3 m at an average time of 10 s, the speed = 3 m/10 s, and the average speed = 0.3 m/s. 

• Optional: If students have access to video tracking software, a tachometer, or a high-speed camera, they may be able to find 

peak speed (the fastest the car travelled during tests) or even several points of instantaneous speed (how fast the car is going 

at any given moment) instead of, or in addition to, the average speed. 

Assemble Data 

• Have teams run the trials, adjusting the variable of mass the team agreed upon initially in the plan. Reminder: Always use the 

same amount of propeller twists if using the rubberband propeller cars; if using the motorized car, be sure the battery is fully 

charged. 

Note: If not using rechargeable batteries, have extras on hand, because the motor will drain the battery. If using rechargeable 

batteries, keep extras on the charger. 

• Teams will measure the length of time the car travels a given distance for each mass. 

• After the information is added to the table, teams will calculate the average time and speed for each payload trial. 

Analyze and Document Conclusions 

• Students should plot their data points on a graph. 

• Students will use average speed (dependent variable) and the mass (independent variable) to make a graph of their results for 

all trials conducted. 

• Students will determine if their hypothesis was supported or not supported by their data. 

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Unmanned Aircraft Systems 

Average Speed Versus Mass 

Average speed, m/s 

Mass, g 

Present Findings 

Post student graphs around the room so all students can easily compare the data. 

Engage students with the following discussion questions: 

• What can you infer from the data regarding the effect of mass on average speed of an object? 

• What were some obstacles your team faced during the investigation process, and how did you overcome them? 

• Were your predictions about your team’s propeller car accurate? Explain. 

• How would you take what you learned about your propeller car to make a better UAV? 

• Based on your findings, what is something you would like to investigate further? 

• Compare your graph to the graphs of other teams and answer the following questions: 

– How is your graph similar to the other graphs? 

– How is your graph different from the other graphs? 

– What are possible reasons for these similarities and differences? 

– Were there any trials performed by your team or another team with unexpected outcomes? If so, why do you think that was? 

Extensions 

• Measurement extension: Students can use a smartphone and/or a computer for digital video analysis of instantaneous speed. 

Examples of video analysis tools are Tracker (Open Source Physics), Logger Pro (Vernier Software & Technology), and Vernier 

Video Physics (Vernier Software & Technology). 

• Ask students to design their own controlled investigation with the propeller car and brainstorm other independent variables they 

could change besides mass. 

• Students could draw a line or curve of best fit for the data. In addition, ask students to find the equation of the line or curve of 

best fit. Spreadsheets can make this easier and can also be used to quickly measure the fit (r2 value) of the formula. 

Resources 

Mass vs. Weight 

https://www.nasa.gov/pdf/591747main_MVW_Intro.pdf 

NASA STEMonstration Classroom Connection: Newton’s Second Law 

https://www.nasa.gov/sites/default/files/atoms/files/stemonstrations_newtons-second-law.pdf 

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Unmanned Aircraft Systems 

Activity Two: Propelling the Payload With

Electric Propulsion 

Student Handout 

or 

Your Challenge 

Your team will explore the challenges of electric propulsion in flight. You will use a propeller 

car to represent an unmanned aerial vehicle (UAV) as you investigate the effect of varying 

mass on average speed. In this experiment, the mass represents the weight of the battery. 

Note: The car and means of propulsion must remain constant. 

Criteria Constraints 

Students may utilize a commercially available propeller 

car or use the provided instructions to build a motorized 

or rubberband-powered propeller car. 

Students may not deviate from the propeller car 

design or use a different design than other teams. 

Students must design an investigation that 

demonstrates how mass affects the speed of a 

propeller car. 

Pose Question 

NASA is exploring the benefits and challenges of unmanned aircraft systems (UAS) for future 

travel and delivery systems. After watching the introductory videos about UAS and electric 

propulsion, answer the following questions: 

• What are some challenges of electric propulsion for UAS? 

Fun Fact 

The X–57 Maxwell is NASA’s first 

all-electric X-plane. The X–57 will 

have 14 motors that are run by 

16 batteries weighing a total of 

360 kg (800 lb). This X-plane is 

being developed to demonstrate 

that electric propulsion can 

significantly increase efficiency at 

high-speed cruise compared with 

aircraft propelled by traditional 

systems. Electric propulsion will 

result in lower operating costs and 

lower carbon emissions. 

Learn more: 

https://www.nasa.gov/centers/ar 

mstrong/feature/X57_battery_major_milestone.html 

NASA’s X–57 all-electric X-plane is shown 

here in its Mod II configuration. (NASA 

AFRC TV/ Steve Parcel) 

Career Corner 

Timothy Williams is a research 

test pilot at NASA’s Armstrong 

Flight Research Center, and he 

will pilot the X–57 Maxwell. 

Timothy is qualified to fly a diverse 

array of science, research, and 

mission support aircraft for NASA. 

Learn more: 

https://www.nasa.gov/centers/ar 

mstrong/about/biographies/pilots/ 

timothy-williams.html 

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Unmanned Aircraft Systems 

• In what ways are electric propulsion and propulsion on traditional aircraft similar or different? 

• Why is the battery such an important part of a UAS? 

• Is a bigger battery always better? What are the benefits and drawbacks of a bigger battery? 

Develop Hypothesis 

Electric propulsion, while beneficial to our overall environmental impact, does present challenges for scientist and researchers. One 

of the main challenges is that batteries are heavy, and the heavier the object, the greater the force that is needed to move the object, 

according to Newton’s second law. 

• Your team will use a propeller car (representing a UAV) to investigate how mass (representing batteries) can affect average 

speed. You are free to choose the object/s you will use to increase the mass added to the car and the increments by which you 

will increase the mass. 

• If you are having difficulty formulating a testable hypothesis, use the following prompt: “If mass is __________, then the average 

speed of the propeller car will _________________________ .” 

Plan Investigation 

• Construct an electric motor propeller car or a rubberband-powered propeller car. 

• Your team will brainstorm suitable objects to use for mass and develop a testable hypothesis along with a plan for investigation. 

• Once your team has a working propeller car, you will need to prepare for data collection. A sample data table is provided below: 

Amount of mass added 

to test car, g 

Payload 

Time to travel length of course, s Average speed, 

m/s Test 1 Test 2 Test 3 Average 

time 

0 5 5 5 5 2 m/5 s = 0.4 m/s 

5 7 10 10 9 2 m/9 s = 0.22 m/s 

• Your team should pick a standard course length for all of your tests. A 2-m course length is typically enough, but longer or shorter 

courses are fine if there is enough space to test safely. 

• Your team will be using the average (mean) time of three tests per chosen mass. 

• To find the average speed, take the length of the course and divide it by the seconds taken on average; for example, if a propeller 

car travels 3 m in the average time of 10 s, the speed = 3 m/10 s, and the average speed = 0.3 m/s. 

Assemble Data 

• Your team will run the tests, adjusting the variable of mass the team agreed upon initially in your team’s plan. Reminder: always 

use the same number of propeller twists if using the rubberband car; if using the motorized car, be sure that the battery is fully 

charged. 

• Your team will measure the length of time the car travels a given distance for each mass. Add the data to your data table, and 

then calculate the average time and speed for each payload trial. 

Analyze and Document Conclusions 

• Use average speed values (dependent variable) and the mass values (independent variable) to make a line graph of your results 

for all trials conducted. 

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Unmanned Aircraft Systems 

Average Speed Versus Mass 

Average 

speed, m/s 

Mass, g 

Present Findings 

Be prepared to answer the following discussion questions with the whole group: 

• What can you infer from the data regarding the effect of mass on average speed of an object? 

• What were some obstacles your team faced during the investigation process, and how did you overcome them? 

• Were your predictions about your team’s propeller car accurate? Explain. 

• How would you take what you learned about your propeller car to make a better UAV? 

• Based on your findings, what is something you would like to investigate further? 

• Compare your graph to the graphs of other teams and answer the following questions: 

– How is your graph similar to the other graphs? 

– How is your graph different from the other graphs? 

– What are possible reasons for these similarities and differences? 

– Were there any trials performed by your team or another team with unexpected outcomes? If so, why do you think that was? 

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Unmanned Aircraft Systems 

C.2 Electric Motor Propeller Car Instructions 

Gather all needed materials and review the Motorized Propeller Car Tutorial video: https://youtu.be/uPxmCzMyBII. 

Step 1: Create the cargo bay access window. 

Lay one of the bottles on its side and cut a rectangular hole 

that extends approximately 4 cm from the bottom of the bottle 

to approximately 7 cm from the top of the bottle. 

The rectangle should be between 4 and 5 cm wide. 

Step 2: Mount the axles. 

Cut a straw into two 8-cm pieces. Each straw should be wider 

than the water bottle. 

Use low-temperature hot glue or other adhesive to attach the 

straws to the water bottle on the opposite side of the 

rectangular hole that was cut in Step 1. Place the straws 

(axles) far enough apart so the weight is distributed evenly. 

Cut a wooden skewer into two 11-cm pieces and slide the 

wooden skewers through the straws. 

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Unmanned Aircraft Systems 

Step 3: Create the wheels. 

Mark the center of each bottle-cap wheel with a marker. Use a 

pen or pushpin to make a small hole in the center of the 

marking. Make sure the hole is a little smaller than the wooden 

skewer (axle) diameter so it is a tight fit. 

When using thick plastics, use a nail or a craft knife to make 

the holes larger. 

Step 4: Mount the wheels. 

Gently push a skewer through the center of a bottle-cap wheel. 

Slide the skewer through a straw and push into the center of a 

second bottle-cap wheel. 

Repeat with the other two wheels and skewer. 

Make sure the wheels are as straight as possible. 

Note: Wobbly wheels make it difficult for propeller cars to move 

forward. 

Step 5: Wire the motor to the 9-V battery clip. 

Strip the wires connected to the 9-V battery clip. 

Connect the wires from the 9-V clip to the proper terminals on 

the motor. 

• The negative terminal is designated by a “–” sign. Connect 

the black wire to the negative (–) terminal on the motor. 

• The positive terminal is designated by a “+” sign. This is 

where the red wire will connect to the motor. 

If the wires are too short, simply add additional cabling to extend 

the wires from the 9-V battery clip to the motor. 

Note: Some DC motors do not designate a positive and negative 

terminal. If this is the case, simply wire each cable from the 9-V 

battery clip to a terminal on the motor. 

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Unmanned Aircraft Systems 

Step 6: Connect the battery. 

Attach the battery to the connectors on the 9-V battery clip. 

Your motor should run. If not, your battery may be dead, or 

wires may be touching. Troubleshoot the issue. 

Now detach one of the battery connectors to turn off the power 

to the motor. 

Step 7: Tape the 9-V battery to the car. 

Neatly organize the cables inside or along the side of the test 

car. 

Place and center the 9-V battery near the front of the car. It 

should be taped perpendicular to the body of the car. 

Note: Before moving to the next step, ensure that the propeller 

car is balanced. 

Step 8: Connect the hub to the motor. 

Mark the center of the top of a bottle cap with a marker. 

Using the marking as a center point, use a pen to create a small 

hole through the top of the bottle cap. 

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With the bottom of the bottle cap facing toward you, secure the 

bottle cap to the shaft of the motor. 

The bottle cap should be placed about halfway between the tip 

of the motor shaft and the motor. 

Use a moderate amount of low-temperature hot glue or 

adhesive on the inside of the bottle cap to ensure a tight fit. 

Note: The bottle cap (propeller hub) should not sag or rub 

against the motor or the bottom of the water bottle. 

Step 9: Connect the propeller attachment to the propeller 

hub. 

The purpose of the propeller attachment (see photo) is for you 

to attach and reattach the propellers you design or redesign to 

the propeller hub. 

Do not use glue to connect the propeller attachment to the 

propeller hub, because you will need to attach and reattach 

your propeller designs to it. 

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Unmanned Aircraft Systems 

C.2.1 Propeller Attachment Instructions for Activity One, Propeller Design Challenge 

After building either the rubberband-powered or electric motor propeller car, choose one of the options below for attaching propeller 

designs to the propeller car for Activity One: Propeller Design Challenge. 

You have two options when using the propeller 

attachment. 

Option 1: 

Safely cut the threading off of a water bottle. You can use the 

base of this threading to attach your propeller designs to the 

system. 

Option 1 example 

Option 2: 

Safely cut the threading off of the second water bottle, but use 

some of the plastic from the neck of the second water bottle to 

create your propeller design. 

Option 2 example 

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Unmanned Aircraft Systems 

C.3 Rubberband-Powered Propeller Car Instructions 

Gather all needed materials and review the Rubberband-Powered Propeller Car Tutorial video: https://youtu.be/1lNd5Q8Cb2w 

Step 1: Create the cargo bay access window. 

Lay one of the bottles on its side and cut a rectangular hole 

that extends approximately 4 cm from the bottom of the bottle 

to approximately 7 cm from the top of the bottle. 

The rectangle should be between 4 and 5 cm wide. 

Step 2: Mount the axles. 

Cut a straw into two 8-cm pieces. Each straw should be wider 

than the water bottle. 

Use low-temperature hot glue or other adhesive to attach the 

straws to the water bottle on the opposite side of the 

rectangular hole that was cut in Step 1. Place the straws 

(axles) far enough apart so the weight is distributed evenly. 

Cut a wooden skewer into two 11-cm pieces and slide the 

wooden skewers through the straws. 

Step 3: Create the wheels. 

Mark the center of each bottle-cap wheel with a marker. Use a 

pen or pushpin to make a small hole in the center of the 

marking. Make sure the hole is a little smaller than the wooden 

skewer (axle) diameter so it is a tight fit. 

When using thick plastics, use a nail or a craft knife to make 

the holes larger. 

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Unmanned Aircraft Systems 

Step 4: Mount the wheels. 

Gently push a skewer through the center of a bottle-cap wheel. 

Slide the skewer through a straw and push into the center of a 

second bottle-cap wheel. 

Repeat with the other two wheels and skewer. 

Make sure the wheels are as straight as possible. 

Note: Wobbly wheels make it difficult for propeller cars to move 

forward. 

Step 5: Create the anchor for the rubberbands. 

Use the pushpin and the nail to create two holes on opposite 

sides on the mouth of the bottle. Ensure the holes are large 

enough so the straightened paperclip will be able to slide 

through both sides. 

Put the straightened paperclip through one hole, then slide it 

through the center of another paperclip that will be used as an 

anchor, and then out the other hole in the neck of the bottle. 

Bend the ends of the paperclip up and in, locking the paperclip 

in place. 

Step 6: Make the propeller. 

Note: This is an example of a basic propeller that can be used 

for the Propelling Your Payload With Electric Propulsion activity. 

Students will design their own propellers for the Propeller 

Design Challenge. 

Cut off the top portion of the second water bottle. Make a 

horizontal cut on the side of the bottle right before the plastic 

starts to angle toward the neck of the bottle. 

Safety reminder: Hold the bottle top firmly by its cap so 

the scissors do not accidentally contact your supporting 

hand. 

Starting at the cut edge of the bottle, make two cuts directly 

across from each other, cutting straight down and as close to 

the bottle cap as you can. 

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Repeat until you have four to eight equal sections or propeller 

blades. Gently fold them back to a roughly 90° angle (as shown 

in the picture). 

Mark the center of the bottle cap (propeller hub) on the propeller 

with a marker. Use a pushpin to make a small hole in the center 

of the marking. 

Make sure the hole in the bottle cap is a little smaller than the 

wooden skewer (axle) diameter, so it is a tight fit. Do not put 

the skewer in yet. 

Step 7: Prepare your propeller. 

Use the pushpin to poke a hole in the extra bottle cap. 

Use the steel nail to widen the hole a little more. 

Cut a circle out of the bottle cap. It does not have to be perfect. 

Place the skewer in from the top side of the propeller bottle cap 

(propeller hub) and push it in about 4 cm. Put hot glue on the 

underside of the propeller hub to help hold the propeller hub 

onto the axle. 

Note: The purpose of the propeller hub (see photo) is for you to 

attach and reattach the propellers you design or redesign to the 

propeller car, so it is important you do not use glue to connect 

the propeller itself to the propeller hub (bottle cap). 

Make a thick ring of hot glue, 3 cm away from the propeller hub 

on the skewer. Let it cool, then put the plastic circle you just cut 

out onto the skewer. 

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Unmanned Aircraft Systems 

Step 8: Attach the propeller. 

Use the pushpin to make a hole for the propeller’s axle. Make 

the hole at the bottom (base) of the bottle on the same side as 

the cargo bay opening. 

Use the nail to make the opening big enough for the skewer to 

go in and spin freely. Place the axle through the opening. 

Shorten the skewer so there is about 6 cm inside the cargo 

bay. 

Pull one end of a small paperclip and open it slightly. Hot glue 

the other end of the paperclip onto the skewer that is on the 

inside of the cargo bay opening. Glue the paperclip so that it 

will not come off the skewer (propeller). 

Weave together two sets of three rubberbands into a loose 

knot, as shown. 

Connect one end of the rubberband knot to the paperclip 

attached to the propeller skewer. 

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Connect the other end of the rubberband knot to the paperclip 

attached to the mouth of the bottle. 

Your propeller will be loose at this point; this is to be expected. 

Safety reminder: Be sure you are wearing eye 

protection when stretching the rubberbands. 

Step 9: Twist the propeller. 

Twist the propeller by its axle—do not put your finger between 

the blades to spin it. Propellers will usually need to be twisted in 

a clockwise direction, but if your propeller spins backward or not 

at all, try turning the other direction. 

Twist until the rubberbands double over on themselves. Usually 

this will be more than 100 twists. Keep hands and fingers clear 

of the propeller. 

When you are ready, place the propeller car in the designated 

test area and release the propeller! 

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Unmanned Aircraft Systems 

C.3.1 Propeller Attachment Instructions for Activity One: Propeller Design Challenge 

After building either the rubberband-powered or electric motor propeller car, choose one of the options below for attaching propeller 

designs to the propeller car for Activity One: Propeller Design Challenge. 

You have two options when using the propeller 

attachment: 

Option 1: 

Safely cut the threading off of a water bottle. You can use the 

base of this threading to attach your propeller designs to the 

system. 

Option 1 example 

Option 2: 

Safely cut the threading off of the second water bottle, but use 

some of the plastic from the neck of the second water bottle to 

create your propeller design. 

Option 2 example 

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Unmanned Aircraft Systems 

C.4 Basic Propeller Template 

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Unmanned Aircraft Systems 

C.5 Basic Propeller Template Instructions for Activity Two: Propelling the Payload 

With Electric Propulsion 

After building either the electric motor propeller car or the rubberband-powered propeller car, you will need a basic propeller to 

provide thrust for the car. 

Step 1 

Have your Propeller Template ready. 

Measure 7.5 cm from the top mouth of a plastic water bottle, 

and use a marker to carefully draw a line around its 

circumference. 

Step 2 

Neatly cut along the line around the bottle. 

Step 3 

Place the bottle top you just cut out on top of the Propeller 

Template. Looking from the top, align the mouth of the water 

bottle with the center of the template. 

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Unmanned Aircraft Systems 

Step 4 

Each propeller on the template has a number. 

With a marker, write each number on the corresponding plastic 

bottle as shown. 

Step 5 

On the Propeller Template, you will notice four straight lines. 

Draw a line from the neck of the water bottle to each of the 

straight lines. 

Do not cut the plastic yet. 

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Unmanned Aircraft Systems 

Step 6 

Remove the bottle from the template and cut out all four of the 

template’s paper propeller blades. 

Step 7 

Starting with the propeller blade labeled “1,” align the straight 

edge of each paper propeller with the line you sketched earlier. 

Use clear tape to attach each propeller to the plastic bottle. 

Step 8 

Inspect the taped propellers to ensure they are neatly secured 

to the bottle. Cut along the lines slowly. When you are done, 

remove the paper. 

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Unmanned Aircraft Systems 

Step 9 

Gently pull open the propeller blades. 

Step 10 

Finally, screw the propeller attachment onto the propeller hub. 

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Unmanned Aircraft Systems 

A.2 Scientific Research Process (SRP) 

SRP Step Novice 

(0) 

Apprentice 

(1) 

Journeyperson

(2) 

Expert

(3) 

Level of 

student 

knowledge 

(Score) 

Observe 

Student does not 

describe observations 

Student generates a 

description that is either 

unclear or not based on 

observation 

Student generates an 

observation-based 

description that is clearly 

stated 

Student generates an 

observation-based 

description that is stated 

using scientific terms and 

identifies patterns 

Pose questions 

Student does not 

identify the question 

Student incorrectly 

identifies the question 

Student identifies part of 

the question 

Student identifies the 

question completely 

Develop 

hypothesis 

Student does not state 

hypothesis 

Student generates a 

hypothesis that is not 

clearly stated or well 

thought out and is not 

testable 

Student generates a 

hypothesis that is clearly 

stated and testable 

Student generates a 

hypothesis that is 

formulated using 

appropriate terms and is 

testable 

Plan the 

investigation 

Student does not plan 

investigation 

Student does plan the 

investigation, but it is 

largely incomplete (no 

testing of hypothesis) 

Student does plan the 

investigation but does not 

adequately test the 

hypothesis previously 

stated 

Student does plan the 

investigation and 

adequately tests the 

hypothesis previously 

stated 

Assemble 

data 

Student does not 

present data 

Student does present data 

but uses inappropriate 

presentation for the type of 

data 

Student does present data 

and uses the appropriate 

presentation for the type of 

data 

Student presents data that 

show trends or patterns 

(insight) and uses the 

appropriate presentation 

for the type of data 

Document 

conclusions 

Student does not 

document conclusions 

Student does document 

conclusions, but the 

conclusions are incomplete 

or suggest student does 

not understand the 

conclusion 

Student does document 

conclusions and shows an 

understanding of evidence 

interpretation 

Student does document 

conclusions and shows 

understanding of evidence 

interpretations as well as 

any limitations 

Analyze data 

Student does not 

analyze data 

Student makes an 

inaccurate analysis of data 

or does not provide 

justification 

Student makes an accurate 

analysis of data using 

appropriate mathematical 

methods for justification 

Student makes an accurate 

analysis of data and makes 

an appropriate prediction or 

projection based on that 

data 

Present 

findings 

Student does not 

communicate results 

Student shares random 

results 

Student shares organized 

results, but results are 

incomplete 

Student shares detailed, 

organized results with 

group 

Pose new 

questions 

Student does not 

identify a followup 

question 

Student poses an unrelated 

followup question 

Student poses an 

appropriate followup 

question based on findings 

Student poses multiple 

followup questions based 

on findings using scientific 

terms 

Total 

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