prEN IEC 63439-2-1:2026

• Status: Not Published
• Publication Date: 08-Feb-2028
• Technical Committee: CLC/SR 129 - Robotics for electricity generation, transmission and distribution systems
• Current Stage: 4020 - Enquiry circulated - Enquiry
• Start Date: 04-Sep-2026
• Due Date: 10-May-2024
• Completion Date: 04-Sep-2026
• Ref Project: oSIST prEN IEC 63439-2-1:2026 - Robotics for electricity generation, transmission and distribution systems - Part 2-1: General technical requirements for uas for overhead power lines inspection

prEN IEC 63439-2-1:2026 is a CLC/IEC draft standard for robotics in electricity generation, transmission and distribution systems. It specifies general technical requirements for uncrewed aircraft systems (UAS) used to inspect overhead power lines, including low-voltage, medium-voltage and high-voltage networks. The standard is written for manufacturers, inspection service providers and electric power utilities that need a common technical basis for overhead line inspection.

What does prEN IEC 63439-2-1:2026 specify?

prEN IEC 63439-2-1:2026 specifies the basic technical requirements for UAS used for overhead power line inspection. It covers multi-rotor, fixed-wing, composite wing and other configurations, and it includes patrol inspection of low-voltage, medium-voltage and high-voltage overhead lines.

The document is organized into clauses on scope, normative references, terms and definitions, abbreviated terms, UAIS composition, inspection function and performance, electromagnetic immunity performance, safety and security requirements, and payload interface. It ends with two informative annexes that support flight planning and payload communication.

Annex	What it covers
Annex A	Flight course contents for automatic patrol inspection, including the parameters used to describe a flight course
Annex B	Communication protocol data for extra payload action directives and execution results

What are the key requirements of prEN IEC 63439-2-1:2026?

prEN IEC 63439-2-1:2026 combines platform requirements, inspection performance, communications, safety and data interface rules. In practice, it is the document a buyer or engineer would use to check whether a UAS can work safely and consistently near energized overhead lines.

UAIS composition and payloads

Clause 5 says a UAS for overhead line patrol inspection shall include the UA, communication system, mission payload, remote pilot station (RPS) and support equipment. It also allows battery or combustible-fuel energy sources, with combustible-fuel systems expected to conform to the ISO 21384 series.

The standard classifies UAIS by operating environment and by inspection performance. Table 1 separates systems for normal plain and hilly areas from systems intended for plateau and mountainous areas, while Table 2 classifies multi-copter UAIS into three levels based on mass, flight endurance, wind resistance and image clarity. That matters because procurement and acceptance can be matched to the terrain and performance needed for a specific utility network.

Clause 5.3 lists the mission payloads used for inspection: visual optical camera, infrared thermography, LiDAR, ultra-violet camera, multi-spectral camera and radar. The UAIS should support modular integration and the payload mounting interface shall comply with ISO 24354 with a quick-locking structure. That is important for field work because inspection teams often swap payloads between defect detection, thermal checks and corridor mapping.

Environmental adaptation and flight performance

Clause 6 requires stable operation in wind, water exposure, temperature, humidity and low air pressure conditions. The UAIS should maintain stable flight in wind up to 12 m/s, have at least IP54 protection for the UA and payload, operate across 0 C to 45 C and 0% to 95% relative humidity, and support low-pressure operation for plateau and mountainous terrain. For the operator, this means the system has to remain usable in real weather and altitude conditions, not just in a test room.

Navigation and flight control are also tightly specified. The UAIS shall use GNSS or equivalent positioning sensors, and for automatic inspection it should have RTK positioning. The positioning accuracy target is less than 10 cm CEP 95% in open areas and 15 cm CEP 95% in mountain and dense woodland. Clause 6.2 also requires a cross track error below 3 m CEP 95%, hovering accuracy for multi-copter fixed-point monitoring, safe switching between manual and autopilot modes, obstacle detection and avoidance, and quiet operation not exceeding 75 dB.

Communication performance

Clause 6.3 sets expectations for the command-and-control link and the image link. The UAIS shall provide bi-directional data transmission between the UA and the RPS, with a minimum range of 2 km in nominal line-of-sight conditions and 1 km in mountainous areas. Command latency should not exceed 20 ms, image stream latency should not exceed 300 ms, and BVLOS operation calls for end-to-end latency under 300 ms and uptime greater than 99.9%.

These requirements matter because inspection flights are often conducted close to infrastructure where delayed control or video can make the mission unsafe or unusable. The clause also points to redundant or failover C2 links for difficult environments.

Inspection function and data capture

Clause 6.4 requires automatic patrol inspection functions such as waypoint-based flight, flight resumption after interruption, adjustment for sagging wires, and replay of historical courses. It also requires real-time structural adaptation and tracking so the UAIS can follow changing conductor geometry while keeping the camera at an effective viewing distance.

The document also sets performance expectations for the inspection data itself. Visible-light imagery shall support still images and video, manual imaging and automatic imaging at preset points, and automatic geotagging. Clause 6.4.4 specifies camera performance, including resolution, autofocus, zoom, image stabilization and distortion control, while clauses 6.4.5 and 6.4.6 do the same for infrared thermography and LiDAR. In practice, this is what lets a utility judge whether the collected images can support defect analysis, thermal anomaly detection and corridor modeling.

EMC, safety and security

Clause 7 defines four immunity grades, from A to D, based on function loss or degradation during electromagnetic compatibility testing. The individual tests cover radiated radio-frequency fields, power-frequency magnetic fields, electrostatic discharge and pulsed magnetic fields, with minimum acceptable grades stated for each. This helps buyers and test labs verify that the system still behaves predictably near energized equipment.

Clause 8 requires pre-flight self-calibration, continuous display of operational status, a safeguarded return-to-home function, automatic mission abort on C2 loss, and emergency action on low energy. It also requires geo-limitation, alerts for corridor deviation, encrypted and authenticated data links, encrypted storage of images and point clouds, and retention of operational logs for at least one year. For users, these are the rules that link safe operation with cybersecurity and data handling.

Payload interface

Clause 9 defines a standardized payload interface and requires compliance with ISO 24354 for the physical and communication aspects. It also specifies electrical power conditions, protection against electrical faults, serial communication behavior, adjustable baud rate, and data exchange for position, orientation and payload status. This is the part a designer checks to make sure new sensors or cameras can be integrated without custom, one-off wiring and protocol work.

What terms does prEN IEC 63439-2-1:2026 define?

• Mission mode - A mode in which the UA follows predefined waypoints and takes off and lands without manual flight-path control by the remote pilot.
• Manual control mode - A mode in which the operator pilots the aircraft directly and the attitude is not controlled by the closed-loop flight control system (FCS).
• Mission payload - Equipment or a device mounted on the aircraft for detecting, repairing, or collecting and recording information.
• Flight resumption after interruption - A function that records the waypoint when a mission is interrupted and later resumes from that point.
• Uncrewed aircraft inspection system (UAIS) - An uncrewed system that uses a UA platform and mission payload to patrol and monitor overhead line facilities, accessories and line corridors.
• Automatic patrol inspection - An inspection mode in which the UA completes take-off, flight and landing according to a preset command without pilot intervention.
• Beyond the visual line of sight (BVLOS) - Operation beyond the pilot’s direct visual line of sight.
• Ground control station (GCS) - The ground station used to monitor and control the UA and mission task.

Who uses prEN IEC 63439-2-1:2026?

prEN IEC 63439-2-1:2026 is intended for UAS manufacturers, inspection service providers and electric power utilities. Manufacturers use it to design the aircraft, payload interfaces, navigation, safety and communications. Inspection service providers and utilities use it to specify, compare and accept systems for overhead line patrol inspection and asset-condition assessment.

What changed in prEN IEC 63439-2-1:2026 from the previous edition?

prEN IEC 63439-2-1:2026 is identified as the first edition.

Which standards are used with prEN IEC 63439-2-1:2026?

• ISO 19111 - Used for geodetic coordinate referencing in flight course data and waypoint positions.
• ISO 21384-2 - Provides UAS component-related requirements referenced for system composition and fuel use.
• ISO 21384-3 - Supports operational procedure alignment for the UAS described in this document.
• ISO 21384-4 - Provides vocabulary used alongside the terms in this standard.
• ISO 24354 - Sets the general requirements for the payload interface and the physical/communication side of modular payload mounting.
• ISO 5110 - Provides the test method for flight stability of multi-copter UAS under wind and rain conditions.
• ISO 5332 - Provides test methods for UAS under low-pressure conditions.
• IEC 61000-4-2 - Provides the electrostatic discharge immunity test method.
• IEC 61000-4-3 - Provides the radiated radio-frequency electromagnetic field immunity test method.
• IEC 61000-4-8 - Provides the power frequency magnetic field immunity test method.
• IEC 61000-4-9 - Provides the impulse magnetic field immunity test method.

What does the prEN IEC 63439-2-1:2026 document contain?

The document contains the structural requirements for UAIS composition, the performance criteria for inspection flight and payload operation, and the EMC and security provisions that support use near power infrastructure. It also includes tables for environment classification, performance classification and parameter precision, plus annexes for flight course contents and communication protocol data.

Annex A gives the information that should be stored in an automatic patrol inspection flight course, including waypoint position, speed, attitudes and payload actions. Annex B describes packet structures and response behavior for extra payload communication, including action directives, execution results and retransmission handling.

SLOVENSKI STANDARD
01-oktober-2026
Robotika za sisteme proizvodnje, prenosa in distribucije električne energije - 2-1.
del: Splošne tehnične zahteve za UAS za pregled nadzemnih daljnovodov
Robotics for electricity generation, transmission and distribution systems - Part 2-1:
General technical requirements for uas for overhead power lines inspection
Ta slovenski standard je istoveten z: prEN IEC 63439-2-1:2026
ICS:
25.040.30 Industrijski roboti. Industrial robots.
Manipulatorji Manipulators
29.240.20 Daljnovodi Power transmission and
distribution lines
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

129/66/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 63439-2-1 ED1
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2026-09-04 2026-11-27
SUPERSEDES DOCUMENTS:
129/53/CD, 129/62/CC
IEC TC 129 : ROBOTICS FOR ELECTRICITY GENERATION, TRANSMISSION AND DISTRIBUTION SYSTEMS
SECRETARIAT: SECRETARY:
China Mr Jianbin Fan
OF INTEREST TO THE FOLLOWING COMMITTEES: HORIZONTAL FUNCTION(S):

ASPECTS CONCERNED:
Digital content,Electricity transmission and distribution,Electromagnetic Compatibility,Information security and data

privacy,Safety
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submitting ISC clauses. (SEE AC/22/2007 OR NEW GUIDANCE DOC).

TITLE:
Robotics for electricity generation, transmission and distribution systems - Part 2-1: General
Technical Requirements for UAS for Overhead Power Lines Inspection

PROPOSED STABILITY DATE: 2027
NOTE FROM TC/SC OFFICERS:
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IEC CDV 63439-2-1 @ IEC 2026 129/66/CDV

1 CONTENTS
2 FOREWORD . 4
3 INTRODUCTION . 6
4 1 Scope . 7
5 2 Normative references . 7
6 3 Terms and definitions . 7
7 4 Abbreviated terms . 9
8 5 Composition of UAIS . 9
9 5.1 System composition . 9
10 5.2 Category . 9
11 5.3 Mission payload . 10
12 5.3.1 Payload classification . 10
13 5.3.2 Visual optical camera . 10
14 5.3.3 Infrared thermography . 10
15 5.3.4 LiDAR . 11
16 5.3.5 Ultra-violet camera. 11
17 5.3.6 Multi-spectral camera. 11
18 5.3.7 Oblique photography cameras . 11
19 5.4 Support equipment . 11
20 6 Inspection function and performance . 11
21 6.1 Environment adaptability . 11
22 6.1.1 Wind resistance . 11
23 6.1.2 Protection against water and foreign objects . 11
24 6.1.3 Operation temperature and humidity tolerance . 12
25 6.1.4 Low air pressure adaptability . 12
26 6.2 Flight performance . 12
27 6.2.1 Navigation and positioning . 12
28 6.2.2 Flight capability . 12
29 6.2.3 Flight control accuracy . 12
30 6.2.4 Hovering accuracy . 12
31 6.2.5 Mission plan. 13
32 6.2.6 Obstacle detection and avoidance . 13
33 6.2.7 Quietness . 13
34 6.3 Communication transmission performance . 13
35 6.3.1 Data transmission . 13
36 6.3.2 FPV transmission rate . 13
37 6.3.3 BVLOS. 13
38 6.4 Patrol inspection performance . 13
39 6.4.1 Automatic inspection . 13
40 6.4.2 Real-time structural adaptation and tracking . 14
41 6.4.3 Image-capturing capability . 14
42 6.4.4 Visible-light camera . 14
43 6.4.5 Infrared thermography . 15
44 6.4.6 LiDAR . 15
45 6.4.7 Detection of objects . 15
46 6.4.8 Data acquisition results and evaluation . 15
47 7 Electromagnetic immunity performance . 15
48 7.1 Performance criterion. 15
49 7.2 Radio-frequency electromagnetic field immunity . 16

129/66/CDV IEC CDV 63439-2-1 @ IEC 2026
50 7.3 Power frequency magnetic field immunity . 16
51 7.4 Electrostatic discharge immunity . 16
52 7.5 Pulsed magnetic field immunity . 16
53 8 Safety and Security requirements . 16
54 8.1 Safety assurance . 16
55 8.2 Security requirements . 17
56 9 Payload Interface . 17
57 9.1 General . 17
58 9.2 Electrical interface . 17
59 9.3 Communication protocol . 18
60 9.4 Data requirement . 18
61 Annex A (informative) Flight Course Contents . 19
62 Annex B (Informative) Communication protocol data . 21
IEC CDV 63439-2-1 @ IEC 2026 129/66/CDV
64 INTERNATIONAL ELECTROTECHNICAL COMMISSION
65 ____________
67 Robotics for electricity generation, transmission and distribution systems
68 Part 2-1: General Technical Requirements for UAS for Overhead Power
69 Lines Inspection
71 FOREWORD
72 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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111 rights.
112 IEC 63439-2-1 has been prepared by IEC technical committee 129: Robotics for Electricity
113 Generation, Transmission and Distribution Systems. It is an International Standard.
114 This is the first edition.
Draft Report on voting
129/XX/FDIS 129/XX/RVD
116 Full information on the voting for its approval can be found in the report on voting indicated in
117 the above table.
118 The language used for the development of this International Standard is English.
129/66/CDV IEC CDV 63439-2-1 @ IEC 2026
119 This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
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125 specific document. At this date, the document will be
126 • reconfirmed,
127 • withdrawn,
128 • replaced by a revised edition, or
129 • amended.
IEC CDV 63439-2-1 @ IEC 2026 129/66/CDV
130 INTRODUCTION
131 Overhead power-line inspection is critical for detecting defects and hidden hazards before
132 they compromise grid stability. UAS-based inspection can provide flexible access and multi-
133 angle data acquisition. As these systems continue to mature, they are rapidly supplanting
134 manual inspections and are poised for widespread market adoption.
135 This document specifies general technical requirements for uncrewed aircraft inspection
136 systems used for the inspection of overhead power lines. This document provides a
137 framework for UAS hardware, safety provisions, and data acquisition for overhead line
138 inspections across both transmission and distribution networks.
139 The purpose of this document is to provide a harmonized technical framework that ensures
140 the safe and reliable operation of UAS near energized power lines, improves the consistency
141 and quality of inspection data, facilitates interoperability and comparability across different
142 systems and operators, and supports utilities and service providers in the effective
143 deployment of UAS for asset condition assessment.
144 This document is intended for use by UAS manufacturers, inspection service providers, and
145 electric power utilities.
129/66/CDV IEC CDV 63439-2-1 @ IEC 2026
147 Robotics for electricity generation, transmission and distribution systems
148 Part 2-1: General Technical Requirements for UAS for Overhead Power
149 Lines Inspection
150 1 Scope
151 This document specifies basic technical requirements for uncrewed aircraft system (UAS)
152 (products) used for overhead power lines inspection, including UAS with multi-rotor, fixed
153 wing, composite wing and other configurations.
154 This document applies to UAS used for patrol inspection of low-voltage, medium-voltage and
155 high-voltage overhead power lines.
156 2 Normative references
157 The following documents are referred to in the text in such a way that some or all of their
158 content constitutes requirements of this document. For dated references, only the edition
159 cited applies. For undated references, the latest edition of the referenced document (including
160 any amendments) applies.
161 ISO 19111, Geographic information — Referencing by coordinates
162 ISO 21384-2, Unmanned aircraft systems — Part 2 Components
163 ISO 21384-3, Unmanned aircraft systems — Part 3 Operational procedures
164 ISO 21384-4, Unmanned aircraft systems — Part 4 Vocabulary
165 ISO 24354, General requirements for the payload interface of civil unmanned aircraft systems
166 ISO 5110, Test method for flight stability of a multi-copter unmanned aircraft system (UAS)
167 under wind and rain conditions
168 ISO 5332, Civil small and light unmanned aircraft systems (UAS) under low pressure
169 conditions — Test methods
170 IEC 61000-4-2, Electromagnetic compatibility (EMC)—Part 4-2: Testing and measurement
171 techniques— Electrostatic discharge immunity test
172 IEC 61000-4-3, Electromagnetic compatibility (EMC)—Part 4-3: Testing and measurement
173 techniques— Radiated, radio-frequency, electromagnetic field immunity test
174 IEC 61000-4-8, Electromagnetic compatibility (EMC)—Part 4-8: Testing and measurement
175 techniques— Power frequency magnetic field immunity test
176 IEC 61000-4-9, Electromagnetic compatibility (EMC)—Part 4-9: Testing and measurement
177 techniques— Impulse magnetic field immunity test
178 3 Terms and definitions
179 For the purposes of this document, the following terms and definitions apply.
180 ISO and IEC maintain terminology databases for use in standardization at the following
181 addresses:
182 • IEC Electropedia: available at https://www.electropedia.org/
183 • ISO Online browsing platform: available at https://www.iso.org/obp
184 3.1
185 mission mode
186 mode in which a UA follows predefined waypoints and performs take-off and landing without
187 manual flight-path control by the remote pilot
IEC CDV 63439-2-1 @ IEC 2026 129/66/CDV
188 3.2
189 manual control mode
190 mode that an uncrewed aircraft is piloted by the operator and the attitude of uncrewed aircraft
191 is not controlled by the closed-loop flight control system
192 3.3
193 mission payload
194 equipment or device mounted on an uncrewed aircraft used for detecting and repairing
195 operations or for collecting and recording information
196 3.4
197 flight resumption after interruption
198 mission function that an uncrewed aircraft can automatically record the waypoint when exiting
199 or terminating the current mission during flight, and automatically return to the exit waypoint
200 position and continue flying along the planned course when the mission restarts
201 3.5
202 manual imaging
203 photographing function taken by the pilot through specific function keys on the ground control
204 station or the remote controller
205 3.6
206 automatic imaging at preset point
207 photographing function taken automatically according to preset location coordinates and other
208 parameters without manual intervention
209 3.7
210 automatic imaging at preset time interval
211 photographing function taken automatically according to preset time intervals and other
212 parameters without manual intervention
213 3.8
214 uncrewed aircraft inspection system
215 an uncrewed system with UAV as the platform and carrying mission payload used to patrol
216 and monitor the status of overhead line facilities, accessories and line corridors
217 3.9
218 manual patrol inspection
219 operation function that an uncrewed aircraft is manually controlled by the pilot to inspection
220 and detection of the overhead line without the navigation and positioning system, not subject
221 to the closed-loop control of the flight control system
222 3.10
223 automatic patrol inspection
224 operation function that an uncrewed aircraft can automatically complete the inspection
225 mission according to preset command without pilot intervention during the entire inspection
226 process of the take-off, operational flight and landing
227 3.11
228 historical inspection course
229 course generated by editing and combining waypoints recorded and stored during the
230 inspection process, making them available for future flight
231 3.12
232 point turn
233 a manoeuvre where a multi-rotor uncrewed aircraft adjusts its heading while hovering before
234 flying towards the next waypoint
235 3.13
236 RADAR
237 sensor system that uses radio waves to detect the presence, distance, direction and/or
238 velocity of objects.
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239 4 Abbreviated terms
240 BVLOS   beyond the visual line of sight
241 CEP     circular error probable
242 FCS     flight control system
243 FPV     first person view
244 GCS     ground control station
245 GNSS    global navigation satellite system
246 IMU     inertia measurement unit
247 IR       infrared radiation
248 IRT      infrared radiation thermometer
249 LiDAR    light detection and ranging
250 MTOM    maximum take off mass
251 RPS     remote pilot station
252 RTK     real time kinematic
253 UA      uncrewed aircraft
254 UAIS     uncrewed aircraft inspection system
255 UAS     uncrewed aircraft system
256 UV      ultra-violet
257 UART    universal asynchronous receiver and transmitter
258 PWM     pulse width modulation
259 TTL      transistor-transistor logic
260 RADAR   radio detection and ranging
261 5 Composition of UAIS
262 5.1 System composition
263 UAS for overhead line patrol inspection shall include UA, communication system, mission
264 payload, RPS and support equipment.
265 The energy sources of UAS can be battery or combustible fuels. Where combustible fuels
266 used as energy source of a UAS should conform to the ISO 21384 series.
267 5.2 Category
268 The configuration of UA for overhead line inspection can be multi-copter, fixed-wing,
269 helicopter or others.
270 In accordance with the flight altitude at which overhead lines are located, the UAIS can be
271 classified to two categories as Table 1.
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273 Table 1 – Classified by atmospheric pressure environment adaptation
Categories Level I Level II
Flight altitude
3000 5000
m
Air pressure
70 56.699
kPa
274 Note: 1.Level I : intended for normal operation in plain and hilly areas;
275 2.Level II : intended for operation in plateau and mountainous areas.
276 3. The air pressure conditions shall conform to the requirements of ISO 5332.
277 Based on different configurations of functionality and performance parameters, multi-copter
278 UAIS can be classified to three levels. The main technical specifications for each category are
279 shown in Table 2.
280 Table 2 – Classified by inspection functions

Level I Level II Level III
Categories
MTOM mass≤4 kg 4 kg＜mass≤25kg mass＞25 kg
Flight
≥25min ≥35min ≥45min
endurance
Wind
≥5 m/s ≥10 m/s ≥10 m/s
Resistance
Clear pin
Clear pin Clear pin
interpretation in image interpretation in image interpretation in image
Image clarity
captured away from captured away from captured away from
10m 10m 20m
281 5.3 Mission payload
282 5.3.1 Payload classification
283 The specific payload used shall be determined by the overhead line inspection mission
284 requirements. The mission payloads mounted in UA-based patrol inspection should include
285 one or more of the following types: visual optical camera, infrared thermography, LiDAR
286 scanner, ultra-violet camera, multi-spectral camera, radar. UAS should support modular
287 integration, allowing for quick and secure mounting and dismounting of different payloads.
288 Payload mounting interface shall comply with ISO 24354 with quick-locking structure.
289 5.3.2 Visual optical camera
290 Visual optical camera should be the most frequently used payloads in UAIS. They shall
291 capture high-resolution, high-definition photographs of overhead lines, line towers and right-
292 of-ways for subsequent analysis of defects and faults.
293 5.3.3 Infrared thermography
294 Infrared thermography camera should detect thermal radiation of overhead line facilities within
295 infrared waveband, convert the signals into distinguishable images, and detect the
296 temperature variations to identify the fault of the facilities.
129/66/CDV IEC CDV 63439-2-1 @ IEC 2026
297 Infrared thermography camera should be integrated with the visual optical camera as a whole,
298 or be separated as two payloads mounted at the same UA. The optical axes of infrared and
299 visible optical camera shall be the same in the integrated camera.
300 5.3.4 LiDAR
301 LiDAR should capture high-accuracy laser point and image data, which could be subsequently
302 processed to produce accurate overhead lines models and ground surface in the corridor. The
303 laser point shall be used to identify trees or buildings encroaching on transmission corridors
304 and assess clearance distance accurately in 3D space.
305 5.3.5 Ultra-violet camera
306 The UA shall support integration of an UV camera for detecting, inspecting, and analyzing
307 corona discharge on overhead lines. The UV camera shall provide imaging capable of locating
308 the position of corona discharges. The system shall allow correlation of UV images with
309 spatial positioning data to geolocate corona discharge events.
310 5.3.6 Multi-spectral camera
311 Multi-spectral camera shall provide data suitable for vegetation identification and analysis
312 along the corridor, detection of temporal changes in vegetation coverage and condition.
313 5.3.7 Oblique photography cameras
314 Oblique photography cameras mounted on UA should capture clear multi-angle imagery,
315 providing accurate object information about power line components from various side
316 perspectives. This enables high-precision 3D reconstruction
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