2017/18 Contest Year
CONTEST FLYOFF:
19 – 22 APRIL 2018

Mission & Vehicle Design

Download DBF Rules

Mission Task Matrix:


Regional and Business Aircraft


The objective for this year is to design a dual purpose regional and business aircraft.


General


Payloads

  • Mission 1 – no payload
  • Mission 2 –Passengers carried in the passenger compartment; passengers must be carried internally
  • Mission 3 – Passengers in the passenger compartment and payload blocks in the payload bay(s); all passengers and payload blocks must be carried internally
  • All passengers and payload blocks must be secured sufficiently to assure safe flight without possible variation of aircraft CG outside of design limits during flight
  • Passengers
  • - Super Balls (or bouncy balls) as shown in Figure 1
    - Passengers will be provided in tech inspection and on the flight line
    - The nominal size and weight of the balls are provided in Table I

    - The passengers will be randomly selected from a pool of passengers with a distribution as shown in Figure 2  

    DBF Rules 2018 Figure 1

    DBF Rules 2018 Figure 2

  • Passenger Compartment
  • - Each passenger must have its own, individual “seat” with an individual restraint system that accommodates all passenger sizes
    - All seats must be on one level and on a single, planer surface
    - Longitudinal spacing between the largest passenger size must be a minimum of 0.25 inches
    - Side-to-side spacing must accommodate the largest size passengers without interference
    - No more than two adjacent seats and no more than four seats in a single row
    - There must be a longitudinal aisle with a minimum width and height of 2.00 inches running the length of the passenger compartment; if there are only one or two adjacent seats per row, the aisle may be on either side but must still meet the minimum size requirement
  • Payload blocks will be a rectangular cuboid with L (in) + W (in) + H (in) greater than or equal to 9 inches
  • - Teams will provide their own payload blocks
    - No side may be less than 2”
    - Payload blocks may weigh no more than 8 ounces
    - All payload blocks for each team must be the same size (cannot vary by more than ¼ inch per side)
  • Payload Bay(s)
  • - Payload bay(s) must be a completely separate compartment from the passengers compartment
    - Payload bay(s) must be behind and/or below the passenger compartment
  • There is no limit on battery weight this year
  • Aircraft must demonstrate serviceability by replacing Line Replaceable Units (LRUs)
  • - LRUs will be defined in the Ground Mission Section of these rules

General:

Mission Sequence:


  • Aircraft must be designed to be capable of performing all required missions
  • - Aircraft must pass the wing tip load test with the largest payload loading intended to fly
    - The maximum load demonstrated will be recorded and cannot be altered after completing tech inspection
  • The Flight Missions must be flown in order
  • - A new mission cannot be flown until the team has obtained a successful score for the preceding mission
    - Flight Mission 1 and the Ground Mission can be completed in either order
    - Flight Mission 2 cannot be attempted until Flight Mission 1 AND the Ground Mission are successfully completed
  • After successfully completing all three flight missions, teams will be allowed one additional attempt for both Mission 2 and Mission 3 in order to improve their score. A Mission 2 repeat must be attempted before a Mission 3 repeat can be attempted. The Mission 2 passengers and Mission 3 passengers/payload blocks cannot exceed the maximum approved during tech inspection
  • The aircraft will be brought to the staging box ready to load passengers with the payload blocks already installed (Mission 3)
  • The assembly crew member must load the passengers and prepare the aircraft for flight within the 5 minute window
  • If you forget something you must leave the staging box and forfeit the flight attempt
  • Only the assembly crew member, pilot and observer may go to and enter the staging box or Ground Mission area
  • The assembly crew member is the only person who can touch the airplane while inside the staging box while preparing the aircraft for flight
  • The passenger loading and aircraft checkout must be completed in less than 5 minutes
  • - There is no work allowed on the aircraft after the 5 minute loading and checkout time including connection of batteries, receivers, etc. The aircraft must be ready to fly prior to being called to the flight line less the installation of the arming plug
  • After passenger loading and checkout is complete, the assembly crew member may be swapped for a different flight line crew member, if desired
  • Aircraft will use ground rolling takeoff and landing
  • - Takeoff field length will be limited to 150 ft
  • The initial upwind turn on the first lap of each mission will occur after passing the turn judge (signaled by raising a flag).  The aircraft must remain in unaided visual control distance of the pilot at all times. The Flight Line Judge may require turns to be made to remain in a safe visual control range at his discretion
  • Aircraft must complete a successful landing at the end of each mission for the mission to receive a score
  • - A successful landing is outlined in the general mission specification section below
  • The aircraft empty weight will be recorded after each successful flight mission


Tech Inspection


  • The Aircraft will enter Tech Inspection fully assembled and flight ready
  • The Aircraft will undergo the wing tip lift test with the maximum flight payload installed (maximum weight combination of passengers and cargo)

Flight Missions:


Mission 1:  Aircraft Mission Staging


  • There is no payload for the demonstration flight
  • Takeoff within the prescribed field length
  • Teams must complete 3 laps within the flight window
  • There will be a 5 minute flight window for this mission
  • Time starts when the aircraft throttle is advanced for the (first) take-off  (or attempt)
  • A lap is complete when the aircraft passes over the start/finish line in the air (the landing is not part of the 5 minute time window)
  • Time stops when the aircraft passes over the start/finish line in the air at the end of the third lap
  • Must complete a successful landing to get a score

Scoring:
M1 = 1.0 for successful mission

Mission 2:  Short Haul of Max passengers


  • The payload for the Short Haul is passengers
  • - Teams may select the number of passengers flown but it cannot exceed the maximum number of passengers declared at Tech Inspection
  • The passengers must be carried internally
  • Takeoff within the prescribed field length
  • Aircraft must complete 3 laps
  • There will be a 5 minute window for this mission
  • The score will be the number of successfully transported passengers / the total flight time
  • Time starts when the aircraft throttle is advanced for the (first) take-off  (or attempt)
  • A lap is complete when the aircraft passes over the start/finish line in the air (the landing is not part of the 5 minute time window)
  • Time stops when the aircraft passes over the start/finish line in the air at the end of the third lap
  • Must complete a successful landing to get a score

Scoring:
M2 = 2*[N_(#passengers/time)/ Max_(#passengers/time)] , where Max_(#passengers/time) is the highest #passengers/time score of all teams


Mission 3:  Long Haul of Passengers and Payload


  • The payload for the Long Haul is passengers and payload blocks
  • At least 50% of the passengers from Mission 2 must be carried during this mission
  • At least 1 payload block must be carried for Mission 3 but the number of payload blocks carried cannot exceed the maximum number declared at tech inspection
  • The passengers and payload must be carried internally
  • There will be a 10 minute window for this mission
  • The score will be a function of the number of passengers and total payload weight carried times the number of laps completed
  • Time starts when the aircraft throttle is advanced for the (first) take-off  (or attempt)
  • A lap is complete when the aircraft passes over the start/finish line in the air (the landing is not part of the 10 minute time window)
  • Must complete a successful landing to get a score

Scoring:
M3 = 4*[N_(#passengers * total payload (oz) * #laps) /Max_(#passengers * total payload (oz) * #laps)] + 2, where Max_(#passengers * total payload (oz) * #laps) is the highest (#passengers * total payload (oz) * #laps score for all teams

Ground Mission - Field and Depot LRU Replacement:


  • The Ground Mission must be successfully completed before attempting Flight Mission 2 (the Ground Mission and Mission 1 may be completed in either order)
  • The Ground Mission consists of a removal and replacement of a two Line Replaceable Units (LRUs) chosen at random with rolls of a single 6 sided die
  • The Ground Mission will be conducted in 2 stages
  • - Both stages must be completed in 8 minutes
    - After completing Stage 1 teams will continue IMMEDIATELY onto stage 2
  • 2 team members and a pilot may participate in the Ground Mission, only the team members can touch the aircraft
  • Aircraft must be flight ready at the start and finish of Ground Mission
  • Successful completion of each Ground Mission stage will include functional demonstration of the replaced LRUs
  • Stage 1 – Field LRU Replacement
  • - Ground Mission must be completed in 3 minutes
    - Replacement LRU AND tools must start within the payload bay prior to rolling die
    - For Stage 1 a LRU is defined as:
      Roll: LRU
      1: Servo
      2: Rx Battery
      3: Main Propulsion Battery
      4: Control pushrod or pull-pull cable
      5: Landing Gear wheel
      6: Propeller
  • Stage 2 – Depot LRU replacement
  • - All replacement LRUs and tools will start in the designated area
      If a spare is not available, a team may remove the LRU, place it in a designated area and reinstall it onto the aircraft
      Tools are NOT required to start in the aircraft
    - For Stage 2 a LRU is defined as:
      Roll: LRU
      1: ESC – Electronic Speed Control
      2: : Control Surface (chosen at random with additional roll)
        1: Left Aileron/Elevon
        2: Right Aileron/Elevon
        3: Elevator or Left Elevator
        4: Elevator or Right Elevator
        5: Rudder, Upper Rudder, or Left Rudder/Ruddervator
        6: Rudder, Lower  Rudder, or Right Rudder/Ruddervator
        Any surface not present requires a re-roll
      3: Rx - Receiver
      4: Main Landing Gear (if required chosen at random with additional roll)
        Odd: Left
        Even: Right
      5: Motor (if required chosen at random with additional roll)
        Odd: Left or Front
        Even: Right or Rear
      6: Roll Again

Aircraft Requirements:


General


  • The aircraft may be of any configuration except rotary wing or lighter-than-air
  • No structure/components may be dropped from the aircraft during flight
  • No form of externally assisted take-off is allowed. All energy for take-off must come from the on- board propulsion battery pack(s)
  • Must be propeller driven and electric powered with an unmodified over-the-counter model electric motor. May use multiple motors and/or propellers. May be direct drive or with gear or belt reduction
  • Motors may be any commercial brush or brushless electric motor
  • For safety, each aircraft will use a commercially produced propeller/blades. Must use a commercially available propeller hub/pitch mechanism. Teams may modify the propeller diameter by clipping the tip and may paint the blades to balance the propeller. No other modifications to the propeller are allowed.  Commercial ducted fan units are allowed
  • You can change the propeller diameter/pitch for each flight attempt
  • Motors and batteries may be limited in current draw by means of a fuse in the line from the positive battery terminal to the motor controller. There is no set limit on the fuse rating. If used, it is the responsibility of each team to properly size the fuse to protect the battery, motor, and controller against overcurrents from any source.
  • - Fuse(s) must be located such that no propulsion system component: motor; motor controller; or battery may see more current than the stated limit (fuse value) - Fuse must be placed in the positive (+) lead from the battery, and should be as close to the battery(s) as feasible
  • Must use over the counter NiCad or NiMH batteries. LiPo batteries are not allowed. For safety, battery packs must have shrink-wrap or other protection over all electrical contact points. The individual cells must be commercially available and the manufacturers label must be readable/documented (i.e. clear shrink wrap preferred). All battery disconnects must be "fully insulated" style connectors
  • There is no limit to battery pack weight this year. The propulsion battery pack must power propulsion systems only. Radio Rx and servos MUST be on a separate battery pack. Batteries may not be changed or charged during a flight mission attempt.
  • Aircraft and pilot must be AMA legal. This means that the aircraft TOGW (take-off gross weight with payload) must be less than 55-lb, and the pilot must be a member of the AMA
  • Since this is an AMA sanctioned event, the team must submit proof that the aircraft has been flown prior to the contest date (in flight photo) to the technical inspection team. We will provide qualified pilots at the contest on an as-available basis to assist teams who are unable to have their pilot attend
  • The aircraft must remain substantially the same as documented in the report (for example you cannot change a flying wing design to a conventional tail design). You may make small modifications to the design to improve flight performance after the report submission (one example would be changing a control surface size). The three-view drawing supplied in pdf form as described below in the electronic report section will be used to verify the flight article during tech inspection
  • The aircraft must have an externally accessible switch to turn on the radio control system. It cannot be internal or under a panel or hatch.


Safety

All vehicles will undergo a safety inspection by a designated contest safety inspector prior to being allowed to make any competition flight. All decisions of the safety inspector are final.

To speed the tech inspection process each team must present a signed Pre-Tech and First-Flight Certification when called to begin their on-site tech inspection. Teams may not begin the on-site tech inspection without a completed certification. The Pre-Tech and First-Flight Certification sheet is available on the contest website.

The Pre-Tech must be conducted by, and signed off by, a non team member RC pilot or the team faculty advisor. The Pre-Tech will cover the same safety of flight requirements as the on-site tech inspection and will assist teams in making sure they are ready and able to pass the on-site tech inspection the first time. An expanded First-Flight requirement, which also must be signed off by a non team member RC pilot or the team faculty advisor, requires demonstration of a complete flight including take-off, flying a minimum flight pattern, and landing in a pre-designated location without damage to the aircraft. The non team member RC pilot who signs the inspection and flight certifications may be the same as a team's non-student contest pilot.

Safety inspections will include the following as a minimum:

Physical inspection of vehicle to insure structural integrity:

  1. Verify all components adequately secured to vehicle. Verify all fasteners tight and have either safety wire, locktite (fluid) or nylock nuts. Clevises on flight controls must have an appropriate safety device to prevent their disengaging in flight
  2. Verify propeller structural and attachment integrity
  3. Visual inspection of all electronic wiring to assure adequate wire gauges and connectors in use
  4. Radio range check, motor off and motor on
  5. Verify all controls move in the proper sense
  6. Check general integrity of the payload system


Structural verification:

All aircraft will be lifted with one lift point at each wing tip to verify adequate wing strength (this is "roughly" equivalent to a 2.5g load case) and to check for vehicle cg location. Teams must mark the expected empty and loaded cg locations on the exterior of the aircraft. Special provisions will be made at the time of the contest for aircraft whose cg does not fall within the wing tip chord. This test will be made with the aircraft filled to its maximum payload capacity Radio fail-safe check.

All aircraft radios must have a fail-safe mode that is automatically selected during loss of transmit signal. The failsafe will be demonstrated on the ground by switching off the transmit radio. During fail safe the aircraft receiver must select:

  • Throttle closed
  • Full up elevator
  • Full right rudder
  • Full right aileron
  • Full Flaps down


For aircraft not equipped with a particular control, then the safety inspector must be satisfied that the intended function of the fail-safe system will be carried out.

The radio Fail Safe provisions will be strictly enforced:

All aircraft must have a mechanical motor arming system separate from the onboard radio Rx switch. This may be the contest specified "blade" style fuse. Or, an arming plug such as http://wsdeans.com/products/plugs/ultra_plug.html may be used. This device must be located so it is accessible by a crewmember standing ahead of the propeller(s) for pusher aircraft, and standing behind the propeller(s) for tractor aircraft (i.e. the crew member must not reach across the propeller plane to access the arming system). The "Safety Arming Device" will be in "Safe" mode for all payload changes. The aircraft Rx should always be powered on and the throttle verified to be "closed" before activating the motor arming switch. The arming system MUST be mounted on the outside the aircraft (they cannot be behind an access panel or door) and MUST act as the "safeing" device.

Note: The aircraft must be “safed” (arming fuse/plug removed) any time the aircraft is being manually moved, or while loading/unloading payload during the mission. The arming fuse must be removed anytime the aircraft is in the hanger area.

General Mission Specifications and Notes:

  • The aircraft propulsion system(s) must be "safed" (fuse or arming plug removed) during any time when crew members are preparing/handling the aircraft
  • Maximum flight support crew is: pilot, observer, and ground crew
  • Observer and all ground crew must be students. Only the pilot may be a non-student
  • The upwind turn will be made after passing the upwind marker. The downwind turn will be made after passing the downwind marker. Upwind and downwind markers will be 500 ft from the starting line. Aircraft must be "straight and level" when passing the turn marker before initiating a turn
  • "Successful" Landing - Aircraft must land on the paved portion of the runway. Aircraft may "run-off" the runway during roll-out. Aircraft may not “bounce” off the runway
  • Aircraft obtaining “significant” damage during landing will not receive a score for that flight. Determination of “significant” is solely at the discretion of the Flight Line Judge
  • Flight altitude must be sufficient for safe terrain clearance and low enough to maintain good visual contact with the aircraft. Decisions on safe flight altitude will be at the discretion of the Flight Line Judge and all rulings will be final
  • Additional information is included in the FAQ (Frequently Asked Questions)

AIAA Staff Liaison

Alexandra D'Imperio


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