2016/17 Contest Year
CONTEST FLYOFF:
20 – 23 APRIL 2017

Mission & Vehicle Design

Download DBF Rules

Mission Task Matrix:

Tube-Launched UAV

The objective for this year is to design a tube-launched UAV.  The UAV must fit complete inside the launch tube, which also acts as the UAV handling and storage container.  The launch tube must protect the UAV from damage during normal handling and storage.  Upon removal of the UAV from the launch tube, all folded or stowed surfaces or features must move into the flight condition.  Teams must design a UAV and launch tube that minimizes system weight while maximizing speed, range, endurance and payload capacity.

General

  • The UAV must fit entirely inside the launch tube in a “stowed” condition
  • When removed from the tube, the UAV will “transition” to the flight condition
    • All surfaces or aircraft features that are folded, rotated, stowed or otherwise moved to a condition for storage in the launch tube must be moved to the flight condition
    • All surfaces or aircraft features must "move" to flight position using hinges, pivots, or other captive mechanical mechanisms.  Surfaces or aircraft features cannot temporarily separate from the aircraft and use "lanyards" or similar devices to provide a connection to the aircraft with the operator controlling the path the surfaces or aircraft features takes from stowed to flight position
    • All surfaces or aircraft features described above must securely lock in the flight condition without the use of tools or manual release or engagement of any locking features (in other words, all locking features must be self-locking)
    • All surfaces or aircraft features described above may be manually moved or rotated to the flight condition by hand.  Spring loaded or self-deploying mechanisms are not required
  • Payloads
    • Mission 1 – no payload
    • Mission 2 – regulation hockey puck, quantity three (3), the pucks must be carried internally
    • Mission 3 – regulation hockey puck(s); the number of hockey pucks for each team’s payload is a team decision based on maximizing the overall score; the number of pucks carried cannot exceed the number approved during tech inspection (but could be less); the pucks must be carried internally
    • All payloads must be secured sufficiently to assure safe flight without possible variation of aircraft CG outside of design limits during flight

HockeyPuck


Diameter


3 in
Thickness1 in
Weight5.5–6 oz

Regulation Hockey Puck

  • Launch Tube
    • The launch tube must be a right circular cylinder of constant cross-section
    • The launch tube length to diameter (L/D) ratio must be a minimum of 4
    • The launch tube must be completely sealed in the storage and pre-flight condition
      • No perforations, cut-outs or access holes are allowed
      • The ends must have end caps that completely seal both ends of the tube, one or both of which must be removable by hand only for removing the UAV for flight – no tools or aids are allowed to remove end cap(s)
      • The end cap(s) may be secured internally or externally to the tube – if secured externally, the end cap diameter will be used in the minimum L/D calculation and in the RAC circumference
    • The launch tube must provide sufficient support of the UAV and have sufficient strength to pass the ground mission
    • The launch tube empty weight, including end caps and all internal aircraft supports, as well as overall length and maximum cylindrical circumference will be part of the RAC
  • There is no limit on battery weight this year.


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.  The mission 3 payload cannot exceed the maximum number of pucks approved during tech inspection
  • The UAV will be brought to the staging box inside the launch tube with the payload for mission 2 or 3 already installed.
    • 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 launch tube and airplane while inside the staging box or Ground Mission area during removal of the UAV from the launch tube and to move all surfaces and features to the flight condition
    • The removal of the UAV and checkout must be completed in less than 5 minutes.
    • There is no work allowed on the aircraft after the 5 minute removal 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 aircraft pre-flight checkout is complete the assembly crew member may be swapped for a different flight line crew member, if desired.
  • The aircraft will be hand launched in a direction away from the crowd as designated by the flight line judge.
    • Hand launches must be accomplished by holding the fuselage, no wingtip/discus launches allowed.
    • Teams may not use a "hand launch assist" device (such as a spear-thrower or any type of arm extender).
    • The aircraft must be released before crossing the start/finish line in the direction of the flight pattern.
    • For a launch to be ruled "successful" the aircraft must stay airborne after leaving the launcher’s hand. Any contact with the ground or a ground based object constitutes a failed launch.
    • There is no runway length requirement this year.
  • Teams may make a maximum of 3 launch attempts during a single flight attempt. No repairs may be made between launch attempts.
  • 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
  • The launch tube weight will be recorded after a successful ground 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
  • During the tech inspection the team will load the Aircraft into the launch tube with all restraints in place ready for the ground mission


Flight Missions:

Mission 1: Demonstration Flight 

  • There is no payload for the demonstration flight
  • 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 leaves the launcher’s hand during the (first) hand launch (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)
  • Must complete a successful landing to get a score


Scoring:

M1 = 1.0 for successful mission

Mission 2: Speed Flight

  • The payload for the Speed Flight is three (3) regulation hockey pucks
  • The payload must be carried internally
  • Timed flight to complete 3 laps
  • There will be a 5 minute window for this mission
  • Time starts when the aircraft leaves the launcher’s hand during the (first) hand launch (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*(Min_time / N_time) , where Min_time is the fastest time to complete 3 laps for any team

Mission 3: Range Flight

  • The payload for the Range Flight is hockey pucks
  • The number of hockey pucks carried is determined by each team
  • The payload must be carried internally
  • There will be a 5 minute window for this mission
  • The score will be the number of laps flown times the number of hockey pucks carried
  • Time starts when the aircraft leaves the launcher’s hand during the (first) hand launch (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)
  • Must complete a successful landing to get a score 


Scoring:

M3 = 4*[N_(laps*pucks) / Max_(laps*pucks)] + 2

Ground Mission

  • The Ground Mission must be successfully completed before attempting Mission 2 (the Ground Mission and Mission 1 can be completed in either order)
  • The Ground Mission consists of a series of 3 drops from a minimum height of 12 inches onto a hard surface
  • The UAV will be installed and sealed inside the launch tube with the maximum weight payload determined during tech inspection
  • The assembly crew member will lift the launch tube to the required height and when confirmed by the mission official, will release it.  The mission official will confirm a good drop.
    • Drop 1 – flat drop, the launch tube long axis will be parallel to the landing surface; the mission official will select the orientation about the long axis for the drop
    • Drop 2 – end drop, the launch tube long axis will be perpendicular to the landing surface
    • Drop 3 – same as drop 2 on the opposite end
    • The launch tube cannot sustain major damage as a result of the drop tests.  Major damage is defined as follows but is not limited to just this.  The final decision on major damage to the tube will be made by the mission official
      • Visible cracks or perforations (no longer meets the definition of water tight)
      • External features moving or falling off, including end cap(s)
      • Obvious signs that the structural integrity of the launch tube has been compromised
  • After all three drops are completed, the assembly crew member will remove the UAV from the launch tube
    • The UAV must come out in one piece.  Any dislodged items or damage to the UAV will be a mission failure
  • The assembly crew member will transition the UAV to the flight condition – manually rotate or move surfaces or features to the flight condition.
  • The pilot will then verify all flight controls and subsystems are functional, including propulsion
  • The assembly crew member and one other crew member (pilot or observer) will conduct a wing tip test
  • The Ground Mission is successful if there is no major damage to the launch tube or UAV and flight controls and propulsion are functional.


Aircraft Requirements

General

  • The aircraft may be of any configuration excet 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). Energy imparted by the hand launch is allowed and not excluded by this requirement.
  • 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 can not 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 under a 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 fail-safe 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)

 


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