2A. Sub 25kg / Spraying Aircraft and Systems

Information

DJI Agras T10

Design & Manufacturer Details

DJI Headquarters

14th Floor, West Wing

Skyworth Semiconductor Design Building

No.18 Gaoxin South 4th Avenue

Nanshan District

Shenzhen

China

518057

Recognised Standards

DJI Agras T10 holds an ‘EU DECLARATION OF CONFORMITY’. Details can be found here: https://www.dji.com/uk/euro-compliance

Information

DJI Agras T10

Aircraft Flight Duration / Endurance

19 Minutes

Maximum Radio Range of C2 Link

6km (CE)

Maximum Theoretical Service Ceiling

14763 Feet

Maximum Horizontal Flight Speed

20 meters per Second (S Mode)

Minimum Airspeed

N/A - Multirotor

Glide Distances

N/A - Multirotor

Maximum Ascent Speed

5 Meters Per Second (S Mode)

4 Meters Per Second (P Mode)

Maximum Descent Speed

3 Meters Per Second

Precipitation

No precipitation

Max Wind Speed

10 Meters Per Second

Minimum Temperature

0°C

Maximum

Temperature

40°C

Effects of Differing Payloads on the Flight Envelope

N/A

Information

DJI Agras T10

Aircraft Type

Multirotor – Quadcopter

Overall Dimensions

Flight Dimensions:

1958mm x 1833mm x 553mm

Mass with and without fuel

Standalone Mass: 16.8kg

MTOM: 24.8kg

Maximum Payload that can be carried

8kg (Liquid / Solids carried by aircraft for spraying/spreading)

Information

DJI Agras T10

Method of Construction

Commercial off the Shelf system

Materials Used 

Carbon Fibre, Stainless Steel, Aluminium & Plastic

Frangibility of the Aircraft Structure

The Aircraft is non-frangible. Areas of impact damage that results in the aircraft becoming unairworthy, are propellers, rotor arms and motors. Following any impact with the ground, the system will be repaired in conjunction with section 1.3.18A and test flown before re-entry to service.

Information

DJI Agras T10

Number of Batteries

1

Type of Batteries

Lithium Polymer (Li-Po)

Battery Diagram

Battery Mass

3.8kg

Battery Design

14-Cell Intelligent Battery

Battery Output Power

37.39 Wh

Battery Voltage

51.8V – 14 Cells

Storage

Batteries will be set to self-discharge to storage voltage automatically. The batteries will be stored within either DJI Approved storage cases or lithium polymer safe storage methods such as Li-Po Bags or vented ammunition tins

Information

DJI Agras T10

Propulsion System 

4 x DJI Agras T10 Motors

Voltage

11.55V

Number of Motors

4

Number of Propellers

4

Propeller Construction Material

Plastic

Information

DJI Agras T10

Fuel Type 

Battery – Electrical

Fuel Delivery

Electrical Circuitry

Information

DJI Agras T10

Flight Control

Flight is controlled through electrical signals from the Flight Controller. The flight controller instructs the ESC (Electric Speed Controller) to vary speeds, which in turn controls the speeds of the electrical motors and thus the propellers to complete flight manoeuvres. Control surfaces within the UA are fixed-pitch propellers. 

Stabilisation

Aircraft stabilisation is completed automatically. The IMU consists of an accelerometer and a gyroscope, which provide the flight controller with information such as angular rate and orientation. The aircraft is then stabilised by the flight controller varying speeds of the ESC, which in turn vary the speeds of the electrical motors. 

Automatic Take-Off and Landing

GPS enabled Automatic take-off and landing activated via the interface (Phone / Tablet) on the DJI Go 4 App.  

Automatic Return-to-Home

Equipped with automatic return to home function activated by either the Command Unit or via the interface on the DJI Go 4 App.

GPS-enabled Return to Home will activate under the circumstances detailed in section 1.3.10A.

Information

DJI Agras T10

Sensor Details

1x DJI Proprietary Flight Controller

2x GPS Unit

2x Compass Unit

2x IMU (Inertia Management Unit)

1x Spherical Perception Radar

Radar Systems 

The Spherical Perception Radar System, consisting of Omnidirectional Digital Radar and Upward Radar, works during day and night and is unaffected by light or dust. In an optimal operating environment, the omnidirectional digital radar can predict the distance between the aircraft and the vegetation or other surfaces in forward, backwards, and downward directions to fly at a constant distance to ensure even spraying and terrain following capability. The radar system can detect obstacles in all horizontal directions from 30 m away and from 15 m above in the upward direction. It effectively senses the environment and helps to circumvent obstacles in both Route and A-B Route operation modes. In addition, the radar module limits the descent speed of the aircraft according to the distance between the aircraft and the ground to provide a smooth landing. 

The altitude stabilization and obstacle avoidance functions of the radar module are enabled by default and can be disabled in the app. When enabled, the aircraft flies above the vegetation at a constant spraying distance in Route, A-B Route, and Manual Plus operation modes. In Manual operation mode, the radar module can measure the spraying distance above the vegetation or other surfaces, but the aircraft is not able to fly at a constant spraying distance. Obstacle avoidance can be used in any mode. Auto Obstacle Avoidance is disabled by default. Users can enable it in the app. 

Satellite System

GPS+GLONAS+BeiDou+Galileo

Interface

Telemetry details from all sensors and satellite systems can be viewed in the DJI Agras App. Any errors present within the sensors will be flagged up to the pilot, and in some cases (such as an IMU or Compass Error), the UA will prevent the pilot from taking off. 

DJI Agras App will also notify the Pilot if a minimum level of satellites has not been obtained before deployment, which would result in the UA launching in ‘Atti mode’, where GPS assistance is not available. 

Automatic Flight Control

Primary control of the DJI Agras models is complete through an automated flight control program. This is either through DJI Terra or the in-built DJI Agras application within the Remote Control. The RP is always able to intervene with flight control if required. 

Information

Aircraft Detailed within text

ADS-B Receive

The DJI T10 Agras aircraft has of an ADS-B Receive-only system that will detect aircraft that are equipped with an ADS-B Facility. 

This system allows the Remote Pilot to detect aircraft that are equipped and using ADS-B. When AirSense receives an ADS-B signal, the RP is alerted to this via the interface. DJI Airsense provides progressive warnings, together with the live GPS position of the aircraft, present on the DJI Pilot Map. 

The first (or "lowest") level warning occurs when the manned aircraft is detected. All detected aircraft will be displayed in the app (up to 10 aircraft at a time). Please pay attention to ensure flight safety. 

The second (or “middle”) level warning occurs two kilometres away from the manned aircraft. Please pay attention to avoid any hazards. 

The third (or “highest”) level warning occurs one kilometre away from the manned aircraft. Please avoid the manned aircraft immediately. 

Below is a diagram of the warnings displayed to the remote pilot within the top bar of the DJI Pilot screen. 

Electronic Conspicuity (EC)

The system is not present within the aircraft covered within volume 1B 

Information

DJI Agras T10

Take Off and Landing Aids

Landing skids are located along the length of the Port and Starboard side of the DJI Agras T10 to assist with landing and take-off.

Information

DJI Agras T10

Payload Summary Details 

The DJI Agras T10 has an integrated 8-litre tank that can be filled with liquids to be sprayed via the arm nozzles. An optional spreading system can be attached.

Mass

The maximum mass that can be carried within the liquid or solid tank is 10kg

Spray Nozzle Diagram

Red Arrows indicate Spray Nozzle location

Spray payload

Agricultural liquids will be sprayed. Upon the granting of an application certificate by the HSE, this will include regulated liquids such as chemical pesticides. 

Spreading system

An optional spreading system can be attached to the Agras T10. Technical manual, detailing the attachment process is available here: 

https://dl.djicdn.com/downloads/t30/20210929/T30_T10_Spreading_System_3.0_User_Guide_v2.0_10langs.pdf

Spreading Payload

Agricultural solids will be spread. Upon the granting of an application certificate by the HSE, this will include regulated solids such as chemical pesticides. 

Information

DJI Agras T10

Return to Home Features

Three categories of return to home exist within the DJI Agras T10. These are Smart RTH, Low Battery RTH and Failsafe RTH. All systems autonomously return the aircraft to the designated GPS home point.

Failsafe RTH

The Forward Vision System allows the aircraft to create a real-time map of its flight route as it flies. If the Home Point was successfully recorded and the compass is functioning normally, Failsafe RTH automatically activates after the remote-control signal is lost for more than two seconds. 

When Failsafe RTH is activated, the aircraft starts to retrace its original flight route home. If the remote-control signal is re-established within 60 seconds of Failsafe RTH being activated, the aircraft hovers at its present location for 10 seconds and waits for pilot commands. 

Low Battery RTH

Low Battery RTH is triggered when the Intelligent Flight Battery is depleted to the point that the safe return of the aircraft may be affected. Return home or land the aircraft immediately when prompted. DJI Pilot displays a warning when the battery level is low. The aircraft will automatically return to the Home Point if no action is taken after a ten-second countdown. The user can cancel RTH by pressing the RTH button or the Flight Pause button on the remote controller. 

Smart RTH

If the GPS signal is sufficiently strong, Smart RTH can be used to bring the aircraft back to the Home Point. This is completed by tapping the land button in the DJI Pilot App, or by pressing the RTH button on the Command Unit. 

Vision Position System & Infrared System

During RTH procedures, radar within the aircraft ensures that the aircraft does not collide with any objects. 

Geofencing

DJI Flysafe Database is pre-installed within the aircraft and the Command Unit. This prevents the UA from flying in high-risk areas and prevents the aircraft from breaching altitude restrictions.

Geocaging

Although geographical geo-caging is not utilised during operations, the aircraft will be geocaged throughout operations by setting the maximum altitude and distance the UA can be from the RP. 

Information

DJI Agras T10

C2 Protocol

DJI Proprietary – Occusync 2

C2 Transmitting Power

2.400 - 2.4835 GHz

CE: <20dBm

5.725 – 5.850 GHz

CE: <14dBm

Maximum Operating Distance (CE)

6000m

Operating Frequency

2.400 – 2.4835 GHz

5.725 – 5.850 GHz

Video Transmission

2.400 – 2.483 GHz

5.725 – 5.850 GHz

Transmission Security

C2 link security is ensured through proprietary DJI security algorithms.

The C2 link is also secured by pairing the remote and UA together, ensuring no other remote can control the UA.

Information

DJI Agras T10

Summary

Combined interface tablet and remote control. 

Remote Control System

Proprietary ‘Smart Controlled’

Command Unit Name

DJI Smart Controller Enterprise

Command Unit Interface

Remote Current / Voltage

Built-In Battery

5000 Ah / 7.2V

External Battery

4920 mAh / 7.6V

Remote Control Battery Type

Lithium Polymer

Battery

Built-In Battery

5000 Ah 

External Battery

4920 mAh 

Operating Temperatures

-20°C - 50°C

Interface

Integrated Android tablet. 

Interface Power Arrangements

All interfaces attached to the Remote Control will have an independent power supply system.

Emergency Power Supply

In the event of a low battery in either the Interface or the Remote Control, tasking may continue if an external battery pack is attached to the device with the low battery warning. 

Firmware and Software Updates

Refer to the policy for all updates defined within section 1.3.12A.

Information

DJI Agras T10

Single Point of Failures Identified within UAS

• Propeller Failure

• Propeller Mounting Failure

• Motor Failure

• Motor Mount Failure

• Rotor Arm Structural Failure

• Electronic Speed Controller

• Single Battery Failure

• Power Management Unit Failure

• Power Distribution Failure

• Flight Controller Failure

Known Failure Mode

Preventative Strategies

Propulsion Failure Modes

Complete loss of a single propeller with the T10, or significant damage, or a single propeller of the T10, will result in difficulty with control of the UA, uncontrollable flight profile or uncontrolled descent into terrain. 

• Propellers are checked for damage and airworthiness during pre-flight checks.

• The attachment of the propeller to the propeller mounting is checked during pre-flight checks. 

• Propellers are checked as part of the maintenance regime.

Failure of the propeller mounting of the T10 will cause the ejection of the propeller from the propeller mounting,

• Propeller mountings are checked for damage and airworthiness during pre-flight checks.

• Propellers are checked as part of the maintenance regime.

Single motor failure of the T10 will result in the UA uncontrollably descending into the terrain. 

• The UA will warn of any issues with the motors, such as a ‘motor blocked signal’ before take-off and whilst in flight. 

• Motors are visually checked during pre-flight checks. 

• Motors are checked as part of the maintenance regime. 

With the T10, failure of the motor mounting will cause the motor to dismount from the rotor arm, causing the UA to descend uncontrollably into the terrain. 

• Motor mountings are visually checked during pre-flight checks. 

• Motor mountings are checked as part of the maintenance regime.

Failure of a single electronic speed controller, for the T10, during flight will result in an uncontrollable flight profile, resulting in the UA uncontrollably descending into terrain. 

• The UA will conduct a check of the ESC and will present an alert if there is an issue before the flight is undertaken.

• The UA will not be flown in any precipitation, this presents a historical risk to DJI ESCs. 

Structural Failure Modes

Failure of a single rotor arm during the flight will cause the T10 UA to descend uncontrollably into the terrain.

• Rotor arms and mounts are checked for damage during pre-flight checks.

• Rotor arm condition is checked as part of the maintenance regime. 

Power Failures

Single battery failure in the DJI Agras series will cause an immediate full loss of power, resulting in the UA uncontrollably descending into terrain. 

• The battery is checked for swelling and damage during pre-flight checks.

• The UA will self-check the battery for any issues. 

• The battery is self-heated to increase performance and prevent a higher internal resistance which can result in false readings.

• The RP will only take off when the battery is above 90%.

• The battery is a smart ‘battery’. As such it will ‘self-manage’ and self-discharge as required. 

• A battery maintenance regime is carried out by the organisation.

Power Management Unit Failure will cause an immediate full loss of power, resulting in the UA uncontrollably descending into terrain

• The external condition of the Unmanned Aircraft is checked before any flights are undertaken.

• Only genuine DJI batteries are utilised to mitigate the risk of incorrect power loads damaging internal circuitry.  

Power Distribution Failure will cause an immediate full loss of power, resulting in the UA uncontrollably descending into terrain

• The external condition of the Unmanned Aircraft is checked before any flights are undertaken.

• Only genuine DJI batteries are utilised to mitigate the risk of incorrect power loads damaging internal circuitry.  

Flight Control Failures

Loss of the required number of satellites for P-GPS mode, resulting in the aircraft reverting to ATTI (Non-GPS) Mode

• A site survey is conducted before every flight. Areas of GPS loss risks will be identified by the Remote and mitigated.

• The Remote Pilot will fly the aircraft in ATTI mode. Following a dynamic risk assessment, the Remote Pilot will either return the aircraft to TOLS or continue to mission in ATTI Mode. 

• All Drone Ag Limited Pilots are trained to fly in ATTI Mode. This skill is revalidated by the accountable manager yearly. 

Loss of command signal between the Command Unit and the Unmanned Aircraft will cause the aircraft to enter Return to Home mode.

• Before a flight, a minimum level of satellites will be located before take-off, to ensure the aircraft enters ‘P-GPS’ mode. 

Flight Controller Failure will cause the aircraft to become difficult to control. 

• The UA will self-check its systems before each flight. If an error with the Flight Controller is detected, the UA will not take off.

• Remote Pilots are taught in emergency procedures and will return the aircraft home immediately.  

Compass error or failure will cause the aircraft to become difficult to control

• The UA will self-check its systems before each flight. If an error with the Flight Controller is detected, the UA will not take off.

• Remote Pilots are taught in emergency procedures and will return the aircraft home immediately. 

Maintenance Check

Pre-Flight Checks

Every 20 Hours or Every 3 Months (Whichever comes first)

Airframe 

• Visual Inspection of the entire Airframe for damage

• Physical Inspection of all areas

• Check correct assembly.

• Checking all Screws & bolts, ensuring tightness. Where required, if screws or bolts are discovered to be loose, thread locker will be utilised. 

Antennas

• Visual check of aircraft antennas

• Visual check for damage.

Rotor Arms