Bronze Propeller Competition

Besides being attentive to traditional technical work, engineers must also consider public health, safety, and welfare in everything we do. Coincident with this aspect, we need to be mindful of global, cultural, social, environmental, and economic factors. Students often lose touch of the fact that "engineering is not done for its own sake, it is practiced in context" ( McMasters & Cummings, AIAA Journal of Aircraft, Vol. 41, No. 1, January–February 2004). 

In summary, young engineers need to be curious of the competition, making connections between the knowledge they have learned and creating products of value. These expectations are an important part of the competition and a foundation for success as a professional engineer.

For the 2027 Boeing Bronze Propeller competition, each team needs to design, build, and fly a fixed-wing vehicle that performs a challenging engineering task, can be easily assembled in the field, and delivers a payload successfully.

The vehicle to be designed, built, and flown must be capable of taking off and landing on a conventional runway (32 ft in length) and carry a single external payload. As part of the competition, each team needs to define its own specific mission that creates unique value. This proposed mission must be effectively explained in a well-written abstract before the competition and showcased using a three-fold brochure during the competition. WSU faculty and external judges will review the abstract prior to competition day, and review the brochure and pitch during Open House by considering at least one of the following values:

• Community health.
• Public safety.
• Public well-being or prosperity.
• Impact on a world-wide scale.
• Lifestyles, occupations, religion, wealth, and educational attainment.
• Environment benefits.
• Economy benefits.

To boost your competition score, you should address as many of these values as possible. The abstract can be viewed as a “pitch” to secure approval/funding from your research organizations/government agencies. Your airplane configuration should support your mission definition.

The abstract, brochure and team’s project pitch judging criteria include:

1) How unique is your design?

2) How meaningful is your design? That is, who will benefit from its use?

3) What societal need does your design serve?

The abstract and brochure score will directly impact your competition score.

• Fly within an indoor or outdoor area roughly 100 x 200 ft in size, approximately four basketball fields in line.
• Take off and land safely from the conventional runway (32 ft in length).
• The airplane should have a minimum flight time of 120 seconds and finish a total of 3+1+2 = 6 laps on the flying field.
• Payload is represented by a tube with either one or two squash balls contained. The team can decide if will fly with the light payload (1 squash ball) or heavy (2 squash balls).
• The squash balls are not constrained in the tube, so can roll the length of the tube in flight.
• Each squash ball weighs 24 g (0.85 oz), has a diameter of 1.58”±0.01”, and is housed in a tube of length 1.75” (for light payload) and 3.34” (heavy payload).
• The team needs to drop the payload in a square payload drop zone of side 12 ft.
• Scoring payload must come to rest within the drop zone. Payloads missing the drop zone will not be counted for scoring. Payloads bouncing into the drop zone do not count as a hit. The number of hits is the number of squash balls successfully dropped.
• For safe payload drop off, all airplanes must have a stall speed lower than 25 ft/s (17 mph), verified by wind tunnel experiment and flight test prior to the competition.
• A crash landing on the runway (including runway overruns) will result in a penalty of 2 points.
• Payload must be mounted externally. To be considered as external payload, at least 75% of each payload should be exposed to open air.
• Each team has 60 seconds to set up their airplane at the beginning of the competition. Penalties will be imposed for overtime.
• Aircraft assembly is timed, and is part of the scoring equation. More information is presented in the Scoring section.
• Bonus points are awarded if payload drop is automated. More information is presented in the Scoring section. 

1. The aircraft must be 100% conceived, designed, and built by team members.
2. Teams are required to register and submit a mission description abstract by March 31^st (see Registration & Abstract section below).
3. The vehicle must be a fixed-wing airplane (no rotorcraft, lighter-than-air, etc.).
4. Only propulsion systems powered by electric motors and LiPo batteries are permitted.
5. The use of carbon-fiber is not permitted.
6. Usage of wood is limited to Bass and Balsa wood (in 1/32”, 1/16”, 1/8” thickness), and plywood (in 1/8” thickness). The motor mount/firewall must use MDF.
7. The use of cardboard is allowed.
8. Only a WSU-designated test pilot will fly the airplane.
9. Each team has three (3) priority flight attempts for the competition. The final score will be the sum of the best two attempts. If time permits, teams will be allowed to attempt more flights.  
10. Flights without returning to the runway will not receive any mission score (excluding landing accidents which will result in penalty points).
11. Aircraft can be repaired and flown again between each mission attempt, if all rules are satisfied.
12. Use of more than 2” of tape to cover or secure anything is prohibited.
13. Critical systems and components must be firmly mounted and quickly accessible.
14. Aircraft changes during the competition that deviate significantly from the initial design configuration are not permitted.
15. A maximum of seven (7) control channels are allowed.
16. A maximum of one (1) ESC, Motor, and Propeller assembly is allowed.
17. All servos must be secured and mounted (no Velcro, tape, wire, or adhesive mounting (including glue/CA)).
18. Undergraduate teams have a total budget of $450 to purchase all supplies for vehicle building, poster printing and related testing equipment.
19. WSU-supplied materials should be considered first. Heavily discounted pre-owned material is available for the first-come-first-served basis. Teams are encouraged to take advantage of this.
20. For all WSU student teams, accurate team records and receipts are required. A mid-semester audit (in Spring) is required for each team. Any external purchase must be approved by the instructor.
21. Battery packs must be off-the-shelf purchases and cannot be modified.
22. Acceptable battery and ESC connector are listed below. Teams should confirm the battery and ESC connection type before purchase.
    • XT-60
    • IC-3
    • XT-30
    • Anderson powerpole connector (only allowed if using WSU owned material)
23. An ESC with a minimum of 1.25 times the motor peak current must be paired with the motor. (i.e Peak 30A motor should be paired with an ESC rated for 37.5 A)
24. The ESC and motor must have 3.5mm bullet connectors. Any other connector type for the motor is not allowed.
25. The paired battery discharge rate should be at least 1.5 times the maximum motor peak current.
26. Teams can have multiple batteries ready for use during the competition day. However, all batteries must be identical (i.e., of the same manufacture, type, voltage, and milliamp-hours).
27. Teams assume all responsibility in ensuring servo, ESC, motor, etc. compatibility.
28. Teams assume all responsibility in ensuring propellers properly mount to the motor.
29. Aircraft wingspan is limited to a maximum of 40 inches.
30. All undergraduate design teams must incorporate a WSU 3x4-ft wind tunnel ATI Mini-45 6-axis balance mounting capability.
31. The use of foam is allowed. However, the foam used cannot exceed 30% of the wing, tail, or fuselage volume.
32. The in-house building and machining of any fiber glass or composite material is NOT allowed under any circumstance.
33. 3D-printed components are allowed. However, materials are limited to PLA or tough PLA. Printing costs should be included in your total vehicle cost as well.
34. Planes cannot be flown unless all team members are in a designated safe area.
35. There is no default or automatic win if there are three or fewer team category entries.
36. Keeping in mind the goals and spirit of the competition, all rules, requirements, constraints, and scoring aspects are subject to interpretation and change by the WSU AE Department and AE 628 instructor.
37. Have fun!

There are three participant categories:

• WSU Undergraduate (1^st Place $3,500, 2nd Place $2,500, & 3^rd Place $1,500) *
• High School (1^st Place $800 & 2nd Place $400) * 
• Professional (1^st Place $500) *

* Note: Prize money is not automatically awarded when there are a small number of entries in a certain category. Teams must complete the mission and score 8 pts in the competition to be consider for prize money.

Teams with an alumni, past AE 628 student, or graduate student member must participate in the professional category. High school or undergraduate teams cannot elect to compete in the professional category (unless team members scored in the top-three in a previous competition).

Don't be shy. Form a team, build a plane, and fly!

Mentors for high school and undergraduate student teams are recommended. Feel free to contact Dr. Matheswaran for help finding a mentor, borrow critical airplane components, work in the PPL lab, and secure supplies.

The following competition scoring equation applies:

Score = AEF*[120/t * PV * HQ - Pen + Bonus] + Hits

Where:

• t is the assembly time, in minutes, that it took to assemble a flight worthy aircraft. It is rounded down to the lowest minute.
• AEF is the Aircraft Efficiency Factor and is defined as:
  
  AEF = 3/(n_s * W_e)
• W_e is the aircraft empty weight in lb. (including battery and all electronics)
• n_s is the number of servos.
• Hits is the number of successful payload dropped on that flight. 
• PV is the product value, determined by the faculty and external judges during Open House.
• HQ is the aircraft handling quality, judged by the pilot during the competition day.
• Pen are the penalties incurred by the team during the competition, which include:
  • Crash landing on the runway (including runway overruns) will result in a penalty of 2 pts. Crash landing includes airplane landing upside down or any major component being critically damaged (i.e. broken wing spar, fuselage spar, snapped tail, etc.)
  • 1 pt penalty if a team exceeds the 60 seconds takeoff preparation and payload loading process.
• Bonus includes:
  • 1 point for automated payload drop.
    • The target zone will be denoted by a white tarpaulin/patterned tarpaulin. If patterned, this pattern will be shared with teams ahead of time.
    • Teams are required to use, broadly, optical means (such as light sensors or image recognition) to automate payload drop.
    • All electronics for payload drop must be within the $450 budget. 
  • 1 point for drop test/landing gear analysis.
    • Aircraft will be released from a height of 3 ft for landing gear analysis. The bonus is awarded if there is no damage whatsoever sustained by the airplane.
    • Note that the airplane must be flight ready with payload installed for the drop test.

 

A team’s final score is the sum of its two best flight scores. Note that penalties are cumulative and carry across all attempts (that is, a penalty incurred on an attempt that is not one of the two best scores is still included in the scoring equation). 

The assembly time (t) of your vehicle strongly relates to many favorable attributes. A fast to assemble vehicle will likely be optimized for simplicity and easy building.

Manufacturing assembly time, in this event, includes only the time it takes to put the many vehicle parts together. The time it takes to make (e.g., laser cut) each vehicle part is not counted. Assembly time is different from the overall manufacturing time. The following assembly related exceptions and restrictions apply:

• The team can lay out and organize all parts, bits, pieces, tools, and adhesives prior to assembly timer start
• Electronic components can be prepared for assembly (e.g., connectors can
• already be installed, wire harnesses can be pre-made) – but not installed or fully assembled
• 3D printed, vacuum formed, or foam parts can be premade
• Assembly related jigs or tooling can be premade and ready to use as well
• Teams are restricted to an approximately 4x4-foot work area
• Adhesive drying time is included in the assembly time
• The team must video record the entire assembly process
• Once the team is ready, a timer will start
• The timer will stop only when the team demonstrates a flight-ready vehicle (i.e., with operational control and propulsion systems)
• Non-WSU teams will have to submit a video verifying the defined assembly time

Prototyping, mockups, and other related efforts prior to the timed assembly are allowed.

However, associated material and item costs must be included in the team budget.

 

PV values range from 0.75 to 1.25, calculated based on the average score from each judge and normalized by the mean and standard deviation of the entire scoring sample. PV is evaluated based on the team’s project pitch and brochure design. Four criteria are used for judging the PV:

• Mission and design uniqueness.
• Mission meaningfulness and value created.
• Technical Information and brochure quality.
• Professionalism and design build quality.

HQ values range from 0.75 to 1.25. The average of the top two scores will be used to determine the scoring of HQ. It is then normalized by the mean and standard deviation of the entire scoring sample. The pilot will score each flight using the following criteria.

• Takeoff and landing performance.
• Maneuvering and turning performance.
• Overall aircraft handling sensitivity.

Teams will be disqualified for their flight attempt if they significantly delay or adversely impact the competition. Specifically, a penalty will be given if:

• The plane leaves the designated flying area.
• The team, in any way, significantly delays the competition.

The team can scratch or abort a flight attempt before entering the flying area without a penalty. Be certain your plane is 100% ready to fly before you get into the flight area.

It’s critical to respect competitor plans for multiple flights during the event. Teams that significantly waste time will be disqualified for their current flight attempt.

The sad reality is that crashes happen. However, keep in mind that many teams can quickly repair and fly their planes again. Never give up!

Teams that suffer a crash will not be disqualified unless they unduly delay the competition (e.g., take too long to recover their plane from the flying area). In some cases, teams may be required to wait to recover their crashed aircraft, for safety or other reasons.

Hard landings, with damage, are very common. In such a case, a mission score will not be recorded. Damage that requires more than 60 minutes to repair is considered significant damage and will result in team disqualification.

Teams are required to register for the competition and, at the same time, to submit their Mission Description Abstract. The process is easy, simply complete the form and email it to Dr. Matheswaran. The deadline for this document is March 30th.

The Mission Description Abstract should specifically address elements discussed in the Background section. The abstract must fit within the allocated space on the form (with an unchanged 12-pt font and 1-inch margins).

Although we really want you to compete, there is no commitment associated with registering.

Competition day is scheduled for 11:00 am - 4:00 pm Saturday, May 1st, 2027.

Flight Entry: Before entering the competition, each team will first get in the queue line. There will be five queue line tables during the competition day. The first table will be the control check table operated by AE 628 instructor. The second table will be the weight station operated by Quang. Each team has 3 priority flights, meaning that if your team has less than 3 flights, you can get into the queue line anytime. If your team has already completed three flights, you can still get in the queue line, but any team that has completed fewer than 3 flights can jump in front of your team at any time.

Any team that was removed from the flight area (excluding the queue line) due to a lack of readiness (taking too long to set up or being removed by the instructor due to any other reason) will lose the current flight attempt and score a zero point.

When two hours are left in the competition (at 2:00 pm), teams without a successful scoring flight will be given flight-line priority.

Weight Station: A student competition assistant will be weighing all airplanes before entry. We will weigh your airplane using 3 scales. All components, excluding the payload, should be weighed. This includes any additional wrapping and protection of your payload.

Control Check Station: The instructor/TAs will operate the control check station and give final approval for the team to enter the flying area. AE 628 Instructor reserves the right to reject any team's entry or remove the team from the flight area if the team is determined as not ready.

Timing: A student competition assistant will record timing during the competition. For the takeoff setup, the timer will start when the team or the airplane touches the conventional runway, whichever occurs first. A 30-second warning will be provided to the team. After the 1-minute time limit, the team will be notified, and a penalty will be imposed for every 10 seconds of additional time used. If the team fails to set up within 2 minutes, they will be removed from the flight area.

Product Value Judging: Judges will walk around each team's table to talk to each team during Open House. Each team should prepare a 2-3-minute elevator pitch for your project and provide your brochure to the judges.

Final Score: The final score and winner will not be announced on the competition day. Competition results will be announced at Open House, and will then be posted on the Bronze Propeller Website. Awards and competition certificates will be presented to the team during the Engineering Open House. Teams should work with Dr. Raju for the prize money transfer after the week of the Engineering Open House.

Technical Feedback: Due to the nature of the competition, the instructor and the pilot will not provide any technical feedback or suggestions to the team's design. The pilot will only provide qualitative feedback on how the airplane feels during the flight, and the team is prohibited from asking for improvement suggestions during the competition.

Queue final call:

45 minutes before the end of the competition, a final queue call will be announced. The queue will close 30 minutes before the end of the competition and no teams can join the queue line and complete a scoring attempt. This rule can be revised by the instructor on competition day based on the length of the queue to allow the event to flow smoothly.

• What's preventing teams from simply copying and pasting (or adapting) a mission for a team last year?  
  Using or even slightly modifying previous mission ideas or abstracts is plagiarism and will result in a zero score or disqualification.
• Can teams make their own payload?
  No – the payload is supplied at the competition.
• Are subassemblies, like a premade wing with control surfaces installed, but not assembled to the fuselage allowed?
  This year, given the assembly time component, subassemblies are not allowed. 

Additional Information or Questions

Contact Dr. Raju or Dr. Matheswaran with any additional questions.

For the 2024 Boeing Bronze Propeller competition, the team need to design and build a vehicle that performs a challenging engineering task and has market value.

The vehicle to be designed, built, and flown must transport removable “tanks” containing liquid. The tanks are represented by two 20 oz. plastic Gatorade bottles. Further details on the payload are presented in the rules and requirements section.

As part of the competition, each teamneeds to invent a context within which their vehicle has broad and ideally, marketable value. This supposed mission must be effectively explained in a well-written abstract. External judges will review and score the abstract prior to competition day by considering the following:

“Does the product have a favorable impact on?”

• Community health
• Public safety
• Public well-being or prosperity
• A world-wide scale
• Different cultures
• Lifestyles, occupations, religion, wealth, and educational attainment
• The environment
• The economy

To boost your competition score, you need to address as many of these values or marketability aspects as possible. Although, the “tanks” will contain water for the flight competition, you may assume the “tanks” contain any type of liquid you want to support your mission definition. Do a good job both inventing and communicating your mission. The abstract can be viewed as a “sales pitch” to secure approval/funding from your management, government agencies, or private investors. Your airplane configuration should support your mission definition. Some things to keep in mind: 1) know your competition – why is your product a better value, 2) investors expect a good return on investment – why will customers buy your product, 3) what is your target customer base. There are other considerations as well. Don’t limit yourselves. The “perceived value” score that you receive from the judges on your abstract will directly impact your competition score.

For the 2023 Boeing Bronze Propeller competition, you need to design and build a vehicle that performs a challenging engineering task and has market value.

The engineering part of the competition is relatively simple. The vehicle needs to be light, quick to build, and drop a payload accurately.

Additionally, you need to invent a context within which your vehicle has broad and, ideally, marketable value. Then you have to effectively explain the mission in a well-written abstract. External judges will review and score the abstract prior to competition day by considering the following:

“Does the product have a favorable impact on?”

• community health
• public safety
• public well-being or prosperity
• a world-wide scale
• different cultures
• lifestyles, occupations, religion, wealth, and educational attainment
• the environment
• the economy

To boost your competition score you need to address as many of these value or marketability aspects as possible. Do a good job both inventing and communicating your mission.

The contest included:

• 12 teams, 11 undergraduate and 1 professional
• 81 flights or attempted flights
• An average MAT of 72
• An average PV of 5.3
• An average Wo of 0.91 pounds
• 5 planes with Wo less than 1.0 pound
• 18 target HITS, by 5 teams
• 2 teams had 6, or more, HITS each
• The winning undergraduate team scored HITS on 60% of their flights
• The winning professional scored HITS on 73% of their flights
• 35 payload drops that missed the target
• Only 2 penalties assessed
• A great crowd, of faculty, staff, students, friends, and family