# PILOT OPERATING HANDBOOK DJI S - 900/Zenmuse H3

- 3D Gimbal



## http://www.airvidz.net

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# Document Change Log **Change Record Date**  **Page/Paragraph Description of Change**  **Change Author:** 9/ 10/2015 Entire Document Initial Release Mark A. Olivet 9/15/2015 Entire Document Formatting Mark A. Olivet

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## DJI S900 **Specifications** The DJI S900 is designed as a “heavy carrier” for equipment such as the Panasonic GH3/4 cameras, the Blackmagic Cinema camera, or the Canon Mark II/III cameras. However, this particular S900 owned by AirVidz LLC has been retrofitted for a smaller gimbal a nd camera, the Zenmuse H3 - 3D and GoPro Hero 3+ camera. The follow ing are specifications for the DJI S900, including this customized configuration: **Frame**  Diagonal Wheelbase 900mm  Frame Arm Length 358mm  Frame Arm Weight(with Motor, ESC, Propeller ) 316g  Ce nter Frame Diameter 272mm  Center Frame Weight (with Landing Gear Mounting Base, Servos) 1185g  Landing Gear Size 460mm(Length)×450mm(Width)×360mm(Height) **Motor**  Stator Size 41×14mm  KV 400rpm/V  Max Power 500W  Weight (with Cooling Fan) 158g **ESC**  Working Current 40A  Working Voltage 6S LiPo  Signal Frequency 30Hz ~ 450Hz  Drive PWM Frequency 8KHz  Weight (with Radiators) 35g **Foldable Propeller (1552/1552R)**  Material High strength performance engineered plastics  Size 15×5.2inch  Weight 13g **Flight Parameters**  Takeoff Weight 4.7Kg ~ 8.2Kg  Total Weight 3.3Kg  Power LiPo Battery (6S,10000 mAh, 25C or 6S,16000 mAh, 25C )  Max Power Consumption 3000W  Hovering Power Consumption 1500W (@6.8Kg Takeoff Weight)  Hovering Time 22min (@16 000mAh& 6.8Kg Takeoff Weight)  Working Env ironment Temperature - 10 ~ +40 C

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Take Off Weights

 With **Zenmuse H3 -** **3D Gimbal** and **GoPro Hero 3+ Camera** o With Pulse 16000 mAh Battery: 14 lbs o With Pulse 10000 mAh Battery: 13 lbs Flight Ti m es

 With **Zenmuse H3 -** **3D Gimbal** and **GoPro Hero 3+ Camera** o With Pulse 16 ,000 mAh B attery: 20+ minutes o With Pulse 10 ,000 mAh B attery : 12+ minutes NOTE: These ti m es are averages, and are based on LIPO usage of no more than 15% (3.6v remaining per cell) .

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## Checklists **DJI S900 Bench Setup and Tests –**  **To Be Conducted at Beginning of Each Operational Day** ☐ All screws/ b olts a re tight . ☐ Ti m er alarm for flight ti m e to not exceed 80% battery capacity . ☐ For PULSE 16,000 mAh Battery: Set Tx Timer to 20 minutes . ☐ For PULSE 10,000 mAh Battery: Set Tx Timer to 12 minutes . ☐ Batteries are secure . ☐ Antennas are secure . ☐ Props balanced . ☐ Props aligned . ☐ Props not chipped . ☐ Check blade s , a r m s, etc. fo r cracks/d a m a ge . ☐ W i ring strapped down and p rotected from abrasive surfaces. ☐ No excessive flexing of motors or boo m s . ☐ Boo m s/ m otors will n o t twist . ☐ Center of gravity is correct . ☐ DJI A2 software is at CURRENT VERSION . ☐ DJI iOSD Mark II software is at CURRENT VERSION . ☐ DJI Zenmuse Gimbal software is at CURRENT VERSION ☐ DJI A2 IMU Calibrated . ☐ DJI A2 Compass Calibrated . ☐ W arning li g hts set for l o w battery :

☐ DJI A2 Controller First Level Alert: 21.6v (yellow flashes; approximately 5 minutes flight time remaining, proceed to landing) . ☐ DJI A2 Controller Second Level Alert: 21.0v (aircraft will automatically reduce power for immediate descent; pilot must expedite landing ) . ☐ Flight b atteries FULLY charged (minimum of 24.0 Volts for 6S LiPo) . Replace any battery whi c h cycles below 80% of rated capacity . ☐ Laptop battery charged (minimum of 12.0 Volts for 3S Lipo)
. ☐ Video Monitor Battery (minimum of 12.0 Volts for 3S Lipo)
. ☐ RC Tx Battery (minimum of 12.0 Volts for 3S Lipo)
. ☐ Video Rx Battery (minimum of 12.0 Volts for 3S Lipo)
. ☐ Spare laptop battery .

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**DJI S900 PreFlight Checklist –**  **To Be Conducted Prior to EACH**  **Flight** ☐ Ground station setup and READY ☐ Ground station v ideo Rx ON ☐ Ground station m onitor ON ☐ Verify video Rx and video monitor battery voltages ☐ Identify t ake - off l ocation ☐ Verify take - off l ocation CLEAR of power lines, trees, structures, vehicles, and debris ☐ Position S900 in take - off l ocation ☐ Extend propeller a rms ☐ Verify all propeller a rms LOCKED ☐ Remove foam propeller locks, extend p ropellers ☐ Camera Lens CLEAN ☐ Identi fy e mergency landing z one ☐ Verify w ind LESS than 1 5 mph constant speed ☐ V isually verify S900 radio and video antennae SECURED ☐ Flight battery INSTALLED and LOCKED ☐ Cent er of g ravity is CORRECT ☐ Radio Tx: all s witches UP ☐ Radio Tx: ON, ☐ Radio Tx: VERIFY battery voltage ☐ Camera l ens c aps OFF ☐ Camera SD card INSERTED ☐ Camera ON ☐ Camera set to RECORD ☐ UAS Power ON ☐ VISUALLY confirm home l ocation LOCK ED (20 blue flashes after minimum of 30 seconds) ☐ Set FLIGHT MODE to ATTITUDE for take - off; verify vi a LED and ground station m onitor ☐ Set Intelligent Orientation (IOC) Mode OFF ☐ Test c amera and g imbal ☐ Set g imbal to FORWARD VIEW for take - off ☐ Verify on ground station m onitor UAS FLIGHT BATTERY VOLTAGE > 24.0 ☐ Verify on ground station m onitor ALTITUE = ZERO ☐ Verify on ground station m onitor AIRSPEED = ZERO ☐ Verify on ground station m onitor GPS SATELLITE LOCK > = 8 ☐ Ground Observer in position and READY

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**Take Off Checklist** ☐ Ground Observer – in position and READY ☐ Ti m er set to START ☐ Set FLIGHT MODE to ATTITUDE ☐ Motor startup/checks ☐ Take - off ☐ Verify horizontal and vertical c ontrols are FREE and CORRECT ☐ Landing g ear UP **Landing Checklist** ☐ Set FLIGHT MODE to ATTITUDE ☐ Landing z one CLEAR ☐ Landing g ear DOWN ☐ Execute l and ing ☐ Engine t hrottle OFF ☐ Set t imer to STOP

**Post -**  **Flight Checklist** ☐ UAS flight b attery DISCONNECT ☐ NOTE flight time on radio Tx ☐ Turn radio Tx OFF ☐ REMOVE UAS flight b attery ☐ Camera recording OFF ☐ Camera p ower OFF ☐ Camera lens c aps ON ☐ Ground station v ideo Rx OFF ☐ Ground station m onitor OFF ☐ Fold propellers and apply foam prop locks ☐ Unlock propeller arms and fold down ☐ Update UAS flight l og ☐ Update battery l og

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**Error Messages and Abnormal UAS Flight Behavior** 1. **White flashes** on LED a. Indicates an IMU m alfunction. Land IMMEDIATELY and det e r m i ne cause. b. Possible causes : i. GPS/Co m p a ss not pointing forward ii. IMU not pointing forward iii. Set up of X, Y, Z for location of IMU and c o m p ass is incorrect 2. **Excessive rocking/instability .**  Possible causes: a. Weak m otor b. Structure flexing from fa tigue or cracks i. Motor m ount ii. Main fra m e iii. Bo o m s c. Loose Bolts causing flexing or m i salign m ent i. Props ii. Mounts d. Props out of balance e. Props m i saligned f. Excessive w i nd speeds or gusts g. Excessive G ains h. Excessive m otor power. Max m otor power m u st a little m ore than ty p i cal ascent power. 3. **Red Flashes** on LED (1 , 2 or 3 flashes with pauses) a. GPS loss (3 is more serious). Land if loss lasts for m ore than 30 seconds. b. Possible causes i. Clouds ii. Struct u res iii. GPS m al f u nction iv. GPS too close to electrical co m ponents v. GPS vibration vi. Radio frequency interference on 1575.42 Mhz

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## Section 1 **– General**  In an effort to mini m i ze costs and m ax i mize sp a re p art s ava ila b ility, m any COTS (commercial off the shelf) components have been util i zed. So m e m ay have slight m odificat i ons to better suit this application. Most COTS products have separate data sheets, asse m bly manuals and instruction m anuals. They are re ference in this docu m ent, with key factors being e m phasized. As with all high technology products utilizing constantly evo lving softwar e , it is i m portant to periodically check for online upgrades to the COTS co m ponents, including hardware, firmware and software. **WARNING** : Great care must be taken with the batteries. Much of this manual and supple m ental info r m ation is devoted to the use and care of the b atteries, es p ec ia lly t h e fl ight b a tt e ri e s. They are less volatile than gasoli n e, th o ugh they sh o uld be treated with the sa m e respect. Beco m e ve ry fa m iliar w ith pro p er techniques of their use. General Characteristics  Pri m arily for ISR (Intelligence, Surveillance, and Reconnaissance)  Economical due to extensive use of COTS products  Low Visual Signature  Low Aural Signature  Quick Launch and Recovery  Short Training Period  Simple Operation  Waypoint Navigation  VTOL  Quick Repairs  Redundant Flight Systems  Safety Return to Home during lost link or low battery  High Degree of Mission Success  GPS navigation aid  Various sensors  18 lb max takeoff weight  Operating Temp Range: - 5°C to +60°C  Flight Modes: Manual and GPS aided waypoint naviga tion  Maximum Operating Altitude: 400 feet AGL (per FAA Title 14 Regulations)  Maximum Operation Wind Conditions: 1 2mph sustained  Propulsion System : LiPo batteries  Takeoff: Manual  Landing: Manual or Automatic  Takeoff/Recovery Area: 5m square

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Important Dimensions  Distance rotor to rotor across the center: 35”  Height with GPS/Compass folded down: 21”  Height with GPS/Compass up: 25”  Length of landing gear skids: 17”  Distance between landing gear skids: 18”  Collapsed size: 22” x 19” Important W eights  No Gimbal o 13.5lbs = S900 NO Gimbal and TBM 21000 o 12.3lbs = S900 NO Gimbal and TBM 15000  GH3/GH4 Gimbal o 17.68lbs = S900 with GH3/GH4 and TBM 21000 o 16.48lbs = S900 with GH3/GH4 and TBM 15000 Motors  Manufacturer: DJI - Innovations  Number of motors: 8  Motor type: 41mm x 14mm  Motor Model Number: 4114 - 11  Motor KV/RPM: 400  Motor max @ 25.2V: 10,000 rpm  Motor Max Power: 500 Watts  Power rating: 3000 Watts maximum power consumption for all 6 motors  Current Max: 100 amps  A m p Draw Typical Average: 55 amps Propellers  Manufacturer: DJI - Innovations  Material: Composite  Number of propellers: 6  Propeller model number: DJI 15 x 5.2  Number of blades: 2 - folding  Propeller Diameter: 15”  Propeller Pitch (fixed): 5.2”  Max rpm : 10,000 rpm Electronic Speed Controllers (ESC)  Manufacturer: DJI - Innovations o Number of speed controls: 6  Speed control model number: DJI 40A Opto  Rating in amps: 40 Amps continuous  Signal Frequency: 30 - 450 Hz  Drive P W M Frequency: 8 KHz Flight Control System  Manufacturer: DJI - Innovations  Autopilot Model Number: DJI A2

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 Components: GPS/Compass, IMU, Master Controller, Power Distribution System, LED Indicator Lighting System, Data Transceiver, GCS Software  Power Consumption: 5W  Operating Tem p Range: - 10°C to +40°C  Software Compatible: Windows 7 , Windows 8  Hovering Accuracy: Vertical : ± 0.5m; Horizontal: ± 2m Analog Wireless Links (Video)  Frequencies: o 2.4 Ghz datalink with WiFi o 2.4 Ghz Command & Control o 1.2 Ghz Video  Power Consumption: <1 watt  Usable Range: <2 km. Flight Battery  Manufacturer : PULSE  Battery chemistry: Lithium Polymer  Battery Capacity: up to 16 ,000 mah or greater depending on max gross weight  Battery cell count required: 6S (6 cells in series)  Battery Voltage: 21V minimum during hover, 22.2V nominal, 25.2V maximum  Battery Rated Disc harge Rate: 25 C minimum  Battery Charge Ra te: 1C  Battery Rest Time between discharging and charging: 15 minutes  Batteries used simultaneously: 1  Recommended Battery Discharge Amount: Not to Exceed 80 % Flight Parameters  Flight Ti m e: 20+ mi nutes typical  Payload Max: 9.5 lbs for battery, camera and gimbal **WARNINGS**  Never power a video transmitter or receiver without an antenna connected or overload failure will occur.  Read all in for m ation r e garding b a tteries contained in this manual and supple m ents.  Batteries are highly flammable and can explode, especially when fully charged. Improper charging, vibration, impact, high discharge, etc. can lead to explosion and fire. Batteries must be charged under constant supervision and using proper pr ecautions.  Batteries fully charged must be handled with extreme care.  Store LiPo batteries at 3.85v per cell . Fully charge just before use.  Fully charged LIPO batteries which are not to be used within 24 hours should be discharged to 3.85v per cell .  Disch arging LIPO batteries in excess of 80% of their rated capacity can cause harm to the batteries. NEVER discharge a LIPO battery below 3.5v per cell.  Using more than one battery at a time requires the proper wiring harness so that the voltage is no more tha n 25.2V. Over voltage will cause serious damage to electrical equipment.  Using more than one battery at a time requires weight and balance checks. Proper CG is critical to performance. Airframe must not be overloaded.  GPS/Co m p a ss m ust be facing forward.

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 Do no t use GPS Mode without GPS lock (minimum of 6 satellite locks).  Use low strength (blue) thread locking compound on all screws.  Wireless Video and Data ranges vary considerably on many factors including weather, equipment, and obstructions. Be prepared for com munication failures.

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## Section **2 –**  **Limitations** Airspeed Limitations  Vne – Velocity to Never Exceed: 15 m/s (34 mph)  Va – Typical Maneuvering Speed – 5 m/s ( 11 mph) Power and Powerplant Limitations  40 A m ps ma x per m otor  40 Amps max per speed control  320 Amps max total  Do not exceed 80% discharge of rated LIPO battery capacity (3.5v per cell).  Do not charge batteries which are warmer than air temperature  Allow batteries to cool after use before charging  Leave an air gap between batteries when m ultiple batteries are used simultaneously Weight Limits  Maximum t ake - off w e i ght: 18 lbs  UAS weight m ust be checked prior to takeoff if any change in equipment is made Center of Gravity Limits  3mm from the center of any of the t h ree pairs of ar m s  Must be checked before every flight to ensure batteries were installed in the proper location.  Check all 3 pairs of arms before flight Maneuvering Limits  This aircraft is intended for non - aerobatic operations  G - loading maximum: 2G Temperature Limits  Operating Te m p Range: - 10°C to +40°C  Allow UAS to acclimate to outside ambient air temperature for at least 20 minutes prior to flight  In cold temperatures o Keep IMU at room temperature if possible before the flight o Keep Batteries above 5°C before flight o Do not fly with any frost or ice on the propellers  In warm temperatures o Batteries heat up when discharged o The higher the discharge rate the higher the temperature increase during use Weather Limits  Light dust and light rain require the use of a shield for the ele ctronics in the center section.  Light dust and light rain are acceptable for the unshielded motor and ESC.  Maximum demonstrated wind speed tolerance: 15 mph sustained. Range Limits  Fuel o Fuel capacity (battery capacity) is a primary limiting factor.

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 Flying into the wind will use more battery power to travel the same ground distance. Higher air speeds will be required to penetrate the wind which used more battery power. Take this into account when flying a mission.  Where possible, fly upwind at the start of a mission and downwind at the end to avoid depleting the battery before returning to base. Have alternative landing sites available in case of emergency landing. Wireless Link Limitations  Wireless links will be stable in LOS (line of sight) in most conditions  Wireless links are always susceptible to shorter ranges due to  Atmospheric conditions  Other transmission devices in the area  Jamming  Antennas not aligned properly  Improper voltage  Antenna blockage from AV in certain positions  Multip ath reflection off buildings or ground which cause multiple signals to arrive at different tim es and/or phase.

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## Section **3 –**  **Emergency Procedures** Motor Failure  Operation is possible with one m otor/ESC/propeller failure  The two adjacent motors/ESCs will be increased in thrust automatically by the flight controller to overcome the loss  In cases where the airframe is highly loaded the maximum rating of 40 amps may be exceeded by these two motors/ESCs  Operation should be terminated as soon as possible to reduce the possibility of damage to the remaining motors Communication Failure  Video link failure o 5.8 Ghz being the shortest wavelength in general AV use has the least ability to penetrate. This link should be the first to be lost. o It is best to lose video first! It is the least likely to cause a crash when it fails. o 5.8 Ghz can lose link with little warning. o 1.2 Ghz AV can penetrate obstacles much better than 5.8 Ghz; however, be sure that the “lost link” feature on the DJI A2 is set so that the UAS will CLIMB to an altitude at least 20 feet higher than the tallest obstacle in the area prior to returning to the HOME location. o Ensure that the GCS station antennas are perpendicular to the AV. Do not point the antenna at the AV. o Yaw the AV to change the ante nna position o Other links should still be good. Return back to the GCS until link is restored. o Transmitters produce heat when in operation. When overheated they may have thermal protection which interrupts use temporarily. Use of a heat sink or fan may b e required especially with high ambient temperatures. o Higher gain antennas may be used, but do so with caution. High gain antennas are directional. o Multiple antennas using “diversity” can be used. Diversity is a device which determines the best signal, a nd uses that.  RC link failure o 2.4 Ghz antennas can lose link with little warning. o Anything in between the two antennas can cause temporary signal loss especially a person. o Hold the transmitter up in the air and walk in the general direction of the AV (aeri al vehicle). o Ensure that the antenna is vertical. Do not point the antenna at the AV. o The failsafes on the RC link should be set so that the AV returns to home. Should this require a heading change, the antenna may move into a more desirable position and link will be restored. o The onboard equipment may block the signal. Yaw the AV so that the antennas point towards the GCS. o A LRS (long range system) can be used as a permanent solution. This is higher in wattage and usually on 433 Mhz. Low Battery Voltage  Fail - safes can be set such that in the event of low battery power, either due to a failure or too long of a flight, the warning light on the AV will constantly flash amber. This is the first level of warning.  The second warning level is red flashing light s  Auto landing will occur when battery power is low. It may land in a tree or a lake, so this is not desirable.  Landing with 8 5 % (3.6v per cell) of battery depleted is best. Therefore landing with 13,6 00 m ah used and 2,4 00

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m ah remaining of a 16 ,000 mah battery is desirable. Batteries should be drawn down equally when in use if they are both charged equally and both in rel a tiv e l y t h e sa m e conditio n /age.  Do not mix partially charged batteries. Only use completely charged batteries.  NEVER discharge a LIPO battery below 3.5v per cell, since this can permanently damage the battery. GPS Failure  Takeover by the external pilot should happen ASAP using the RC link.  Most often happens due to a low battery.  Keep a spare 3 cell LiPoly battery with the appropriate plug to plug into the charge jack for emergency use. Most chargers are 19V output which is roughly equivalent to a 4 - cell battery. 3 - cell batteries may work. Compass Calibration Failure  If the compass is out of calibration t he warning light will flash red. This is the same signal as low voltage. If the voltage is correct, there is a calibration error.  Recalibrate the compass following the instruction manual Fire  Fires can occur due to a short circuit or battery failure.  Disc onnect the battery ASAP unless there is danger in doing so if there is any electrical issue.  It is not possible to put out a battery fire.  Do not attempt to put out a battery fire. Use a fire extinguisher to put out fires surrounding the battery. A CO2 fir e extinguisher is better than the powder or chemical type. CO2 does not leave a residue. Water can be used though it may cause other electrical component failures. Forced Landings  A lternate emergency landing zones should be chosen ahead of time.  Be sure that the LZ is clear of people to avoid any incidents.  Land in the nearest LZ which is clear of people.  Announce your intentions of landing as loud as necessary to alert people of the incoming UAS .

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## Section **4 –**  **Handling, Service, and Maintenance** Propeller Care  Propellers m ust be chec ked each fli g ht for nicks or cracks  Propellers are designed to last indefinitely if they do not impact dust, dirt or more. Battery Care and Usage  Refer to instruction sheet included from the battery manufacturer. Typ ical information follows. o Batteries are highly flammable and can explode, especially when fully charged. Improper charging, vibration, impact, high discharge, etc. can lead to explosion and fire. Batteries must be charged under constant supervision and using proper precautions. o Batteries fully charg ed must be ha n dled with e xtre m e care. o Any battery which puffs up is considered damaged and must not be used. It is in a dangerous state. Never charge a puffed up battery. o Any battery which holds less than 80% of its rated capacity should be discarded. o Cycle test each battery after every 50 cycles or if a battery is suspected to have lost as significant amount of its capacity to determine the current capacity. o Properly dispose of batteries. First discharge the battery fully using a battery cycler. Bring to a recycler such as a home improvement store. o Always charge flight batt eries un d er “balance” mo de.  Flight Battery Recommended Charge Rate: 1C which takes approximately 1 hour to charge  Flight Battery Maxim um Charge Rate: May exceed 5C. Charge rates higher than 1C will decrease life cycles. Maximum charge rating per the manufacturer will provide 300+ cycles.  Use the lowest charge rate which is practical.  Battery Rest Time between discharging and charging : 30 minutes minimum, 1 hour maximum.  Do not charge if the battery is more than 2°C warmer than ambient, especially if the temperature is above 20°C. The outer surface is cooler than the inner core after use. Damage will occur when charging a warm battery.  Recommended Battery Discharge Amount: 80%. Using more of the capacity of the battery will decrease the life cycles  As battery temperature approaches freezing the capacity of Lithium Polymer batteries decrease. Keep warmer than 5°C before installing in to the UV (unmanned vehicle).  Battery capacity decreases at higher discharge rates. Using more batteries decreases the discharge rate of each battery thereby extending individual battery capacity slightly.  Lower disc h arge rates improve the life cycles.  Batteries are rated at greater than 300 life cycles. 1,000+ life cycles are possible.  Batteries must not be stored above 60% charged state for extended periods.  Batteries should be stored below 25°C for extended periods  Store batteries at 3.85 volts per ce ll . Fully charge just before use.  Fully charged batteries which are not to be used within 24 hours should be discharged to 3.84 volts per cell using the battery discharger.  Using more than one battery at a time requires the proper wiring harness so that t he voltage is no more than 25.2V. Over voltage will cause serious damage to electrical equipment. Preventative Maintenance  Annual Inspection o An approved technician should disassemble the AV and inspect all components for wear and replace

### AirVidz LLC Page 18 any components as required. o Test all batteries for capacity. o Upgrade firmware and software to latest revisions . o Perform test flight prior to executing any missions. o Document all maintenance performed in the UAS maintenance logbook.  500 Hour Preventive Maintenance o An approved technician should disassemble the AV and inspect all components for wear and replace any components as required. o Replace all motors. o Test all batteries for capacity. o Upgrade firmware a nd software to latest versions . o Perform test flight prior to ex ecuting any missions. o Document all maintenance performed in the UAS maintenance logbook.  10 Hour Inspection o An approved technician should visually inspect all UAS components for wear and replace any components as required. o Ensure that all firmware and software is upgraded to the latest versions. o Recalibrate the DJI A2 Inertia Measurement Unit (IMU). o Recalibrate the DJI A2 Compass. o Visually inspect propellers for damage and replace as necessary. o Perform test flight prior to executing any missions. o Visually inspect all exposed wires for abrasions and replace as necessary.