How BVLOS Connectivity Is Powering the Next Generation of Railway Inspections

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Railway networks form the backbone of global transportation infrastructure, spanning hundreds of thousands of miles across varied terrain and connecting cities, industries, and economies. Maintaining such a vast network requires constant monitoring and maintenance to ensure safety and reliability. Beyond Visual Line of Sight (BVLOS) powered drones are transforming how infrastructure managers monitor, inspect, and maintain railway infrastructure, dramatically improving precision, safety, and efficiency. With BVLOS drones, infrastructure managers can move from labor-intensive manual inspections to intelligent, autonomous inspections that can survey entire corridors in a fraction of the time.

In this post, we’ll walk you through the railway industry’s inspection challenges, explain how drone usage helps address them, explore why BVLOS communications is a game-changer for railway operations, detail practical use cases, and demonstrate how Elsight’s Halo connectivity solution delivers the reliability needed to make large-scale BVLOS operations a reality.

Why Traditional Inspection Methods No Longer Meet Modern Railway Demands

Railway infrastructure is extensive and aging in many markets. It includes tracks, signaling systems, overhead wires, bridges, tunnels, and other assets that must be inspected regularly. Traditional manual inspection methods—involving inspectors walking along tracks or traveling in specialized hi-rail vehicles—remain labor-intensive, time-consuming, and increasingly inadequate for today’s vast and complex railway systems.

In 2018, track-related defects resulted in 546 incidents in the United States, incurring over $97 million in damages. In Europe, track and infrastructure defects accounted for roughly 16% of total significant accidents (≈290 incidents) and a large share of railway repair and compensation costs.

Traditional inspection methods face several significant challenges:

• Access difficulties and safety risks: Manual inspections expose personnel to significant risks. Tracks often traverse remote, elevated, or constrained environments (bridges, tunnels, embankments). Inspectors working close to live rail face safety hazards.
• Operational disruption: Manual inspection can mean slowing or halting train traffic to ensure worker safety and access. Acquiring sufficient time on the track to conduct detailed surveys is difficult, especially in areas with high traffic density. These closures are costly and disrupt schedules.
• Scale and frequency: Rail systems cover thousands of miles (or kilometers). Inspecting these regularly is labor-intensive and time-consuming. 
• Data quality and consistency: Ground-based inspections may miss subtle defects (rail geometry shifts, overhead wire deviations, structure movement) or may require equipment that interrupts service. Human visual inspections inherently introduce variability in defect detection, potentially missing critical issues that could compromise safety and operations.

The scope of inspection requirements compounds these difficulties. Rail operators need to monitor not just the rails themselves, but also ties, ballast, fasteners, joint bars, signals, bridges, tunnels, catenaries, and surrounding vegetation. Traditional methods often rely on subjective visual assessments, potentially missing developing problems or misidentifying debris as defects.

 The Benefits of Drone-Based Railway Inspection

Drones are already changing how railways approach inspection, offering capabilities that address many traditional limitations. Drones’ aerial perspectives reveal issues invisible from ground level, while collecting high-resolution imagery and specialized sensor data more accurately than manual methods. The benefits span across multiple dimensions of railway operations. 

• Drones significantly enhance worker safety by reducing the need for personnel to work in dangerous proximity to active tracks. Instead of sending inspection teams to examine miles of track, drones can capture comprehensive visual data while the staff reviews findings from safe locations.
• Drones excel at accessing hard-to-reach areas. Whether inspecting bridges over waterways, tracks through mountainous regions, or infrastructure in remote areas, drones reach locations that ground-based teams would need significant time and resources to access safely. 
• Speed and coverage capabilities transform operational planning. Where manual inspection might cover a few miles per day, drone operations can survey extensive sections of track rapidly and maintain more frequent monitoring schedules without disrupting train operations. 

UK’s Network Rail noted that the use of drones helps “reach areas that are usually difficult to access … including roofs, bridges, coastal areas, the overhead wires that power electric trains and communication masts.”

• Drones prevent operational disruption during inspections. Drones can fly above or alongside tracks without requiring full line closures, and can inspect while trains remain in service.
• Advanced sensors such as LiDAR (Light Detection and Ranging) and high‑resolution cameras can dramatically improve railway drone inspections by enabling accurate, data‑driven infrastructure monitoring. Detailed visual and sensor data allow inspection specialists to identify minor defects, map assets in 3D, and support predictive maintenance without interrupting operations. 
• Faster data acquisition and higher frequency enable more frequent inspections and a shift from reactive to predictive maintenance.

Rail components require precise measurements, such as detecting switch point gaps greater than 1/8 inch (about the width of a credit card) and rail gaps exceeding 2 inches. Missing even small changes can lead to catastrophic derailments.  (CX case study)

Drones can inspect more track in less time, with fewer personnel and without disrupting rail service, while gathering more detailed data than traditional methods, facilitating quicker identification and resolution of potential track faults and diminishing the risk of incidents with unmatched cost efficiency. 

Drone-based inspection is a compelling enhancement to traditional methods. But to truly unlock its potential—especially across long rail corridors, through remote terrain and at high frequency—it needs to go beyond conventional Visual Line Of Sight (VLOS) operations. 

The Game-Changing Evolution of BVLOS Drone Connectivity

While standard line-of-sight drone operations offer substantial benefits, BVLOS (Beyond Visual Line Of Sight) technology represents a paradigm shift in what’s possible for railway inspection. BVLOS communications removes the constraint that has limited drone operations since their inception: the requirement for operators to maintain visual contact with their aircraft.

Safer Operations and Faster Turnaround

BVLOS connectivity fundamentally changes the scale at which railway drone inspections can be conducted. Conventional drones operate under VLOS or EVLOS (Extended VLOS) constraints, where an operator (or observers) must maintain sight of the drone, limiting their range and automation.

BVLOS drones are designed for remote operation, covering longer stretches of track in a single flight and reducing the need for redeployments. A single drone mission can inspect dozens of miles continuously, providing comprehensive coverage that would require multiple traditional drone flights or days of long-distance travel and on-site inspection. 

BVLOS drones can operate effectively across diverse conditions that challenge conventional systems, including urban corridors, rural expanses, tunnels, and challenging terrain. In the rail environment, this means long corridor inspection flights without line closures or visual observer chains.

Safer Operations and Reliable connectivity

BVLOS communication enables drones to operate safely and efficiently in hazardous or difficult-to-access environments, such as tunnels, bridges, steep embankments, or remote track sections. With reliable long-range connectivity, operators can deploy drones rapidly without sending personnel into dangerous areas or halting train operations.

 Remote Control from Anywhere in the World

One of BVLOS communications’ most transformative aspects is location independence. Drone operators don’t need to be near an inspection site. They can control an aircraft from anywhere with secure network connectivity, overseeing missions across multiple locations without traveling. Response times improve dramatically because strategically positioned drones can launch immediately, without waiting for inspection teams to travel to the site. The result is a safer, more efficient, and data-rich inspection process that strengthens asset-management systems and supports predictive maintenance planning.

Scaling Operations Through Centralized Fleet Management

BVLOS communications enable centralized fleet management. Instead of deploying local individual operators, skilled pilots oversee multiple drones simultaneously across the railway network from remote control centers.

This centralized approach significantly reduces labor costs while leveraging economies of scale by distributing the cost of highly trained operators across multiple aircraft, each conducting separate missions.

In 2021, BNSF began routine BVLOS flights across its 32,500 route-mile network, which spans 28 states and three Canadian provinces. Operating under one of the first FAA’s national Class G airspace waivers, BNSF performs about 1,200 flight hours per month across two intermodal facilities. Dedicated drone pilots handle remote operations at BNSF’s Flight Center in Fort Worth, Texas.

BVLOS Drones in Action: Use Cases in Railway Inspection and Monitoring

BVLOS drone technology supports diverse inspection and monitoring applications across the railway operations:

• Track and rail inspection: Drones equipped with high-resolution cameras and thermal sensors detect rail defects, track misalignment, gauge issues, and developing cracks before they become critical failures. Thermal imaging reveals electrical problems in rails and detects stress points invisible to visual inspection.
• Infrastructure asset monitoring: Regular drone surveys document the condition of bridges, tunnels, signals, and support structures. Detailed 3D models can help track degradation over time, enabling predictive maintenance scheduling based on actual condition trends rather than fixed intervals.
• Vegetation management: Overgrown vegetation poses risks to safe railway operations, potentially interfering with signals, damaging overhead lines, or creating fire hazards. Drones can easily capture vegetation encroachment before it becomes problematic.
• Incident response and trespass detection: Disruptions from trespass incidents significantly impact service efficiency. BVLOS drones enable rapid response to trespass incidents, helping security teams locate and intercept trespassers quickly, reducing delays and enhancing safety.

Rail traffic is often halted entirely for safety whenever someone is detected on the tracks. The UK’s Network Rail report shows over 1800 hours of train delays attributable to trespass in the 2023/24 financial year. It’s a 15% increase over the previous year, which makes trespassing one of the biggest causes of late running. 

• Emergency and disaster assessment: After severe weather, earthquakes, floods, or other emergencies, immediate information about track conditions is required before resuming operations. Drones provide rapid damage assessment without exposing inspection teams to hazardous conditions, accelerating recovery timelines.
• Construction and maintenance oversight: Drones monitor track work progress, documenting conditions throughout projects to help verify completed work against specifications. This aerial documentation provides valuable records for quality assurance and project management.

Elsight’s Halo: Connection Confidence for Accurate Railways Inspection

Reliable connectivity forms the foundation of successful BVLOS operations. Without robust communications, drones cannot maintain the command and control necessary for safe and effective drone missions. Elsight’s Halo BVLOS communications module delivers connection confidence even in areas with varying signal availability, ensuring continuous connectivity for accurate inspections.

Halo’s reliable connectivity stems from the platform’s multilink architecture. Rather than relying on a single communication pathway that leaves connectivity vulnerable to signal loss, Halo aggregates diverse communication paths into a single virtual pipe and manages seamless network handoffs to maintain continuous drone control and data streaming. Halo’s connectivity remains stable as drones transition across vast areas, enabling precise data collection. 

Key benefits for railway inspections: 

• Multilink aggregation for continuous coverage. Halo seamlessly combines multiple communication channels—public and private cellular networks, satellite links, and other RF technologies—into a single, secure communication tunnel. This bonded multilink connection pipe ensures reliable communication and control, even across remote rail corridors or complex terrain.
• Automatic failover for uninterrupted connectivity.  Halo continuously monitors all active links and instantly switches to the most stable channel when degradation occurs. These automatic soft handoffs guarantee continuous command-and-control and real-time data transmission, eliminating communication dropouts during long-distance flights.
• High-bandwidth data transmission. Halo-powered drones can stream high-definition video and sensor data in real time, supporting detailed visual inspections and comprehensive analysis of railway infrastructure, from overhead lines to track geometry and bridge structures.
• BVLOS regulatory compliance – Regulatory approval for BVLOS missions depends on a proven, secure, and redundant communication link. Halo provides the reliable and fail-safe architecture required to meet regulatory standards, helping drones meet the “well-connected path” requirements and gain BVLOS certification for long-range drone missions.
• Cellular coverage mapping tool. Elsight’s HeatSight cellular coverage tool maps RF signals from a drone’s perspective, visualizing signal strength through altitude-based, time-aggregated heatmaps. HeatSight enables operators to plan safer, more reliable flight paths, optimizing connectivity throughout the mission. 
• Rapid deployment and operational readiness. Designed for field efficiency, Halo enables fast deployment whether for scheduled maintenance or emergency response. 

• Proven performance in real-world operations. Halo is trusted across multiple industries for mission-critical connectivity in challenging environments. Its proven track record makes it an ideal choice for rail operators seeking to scale drone-based inspections with confidence and continuity.

AviSight, a provider of critical infrastructure inspections, leverages Halo-powered BVLOS drones to monitor and maintain over 2,000 miles of pipeline networks across diverse and demanding environments.

Drones powered by robust BVLOS connectivity platforms, such as Elsight’s Halo, are transforming railway inspection and monitoring. From enhancing safety and reducing costs to enabling rapid incident response and comprehensive monitoring, these capabilities position forward-thinking railways to meet the challenges of maintaining increasingly complex networks while meeting rising safety and efficiency expectations.

FAQs

1. What regulatory approvals or waivers are required for BVLOS railway inspections, and how does Halo help meet those requirements?

BVLOS railway inspections need FAA Part 107 waivers (or future Part 108 permits post-finalization) in the US, or EU NAA Specific Category/SORA approvals in Europe, proving safe C2 reliability, DAA/risk mitigation, Remote ID, and corridor operations. Elsight’s Halo supports compliance via multilink bonding (cellular/sat/RF) for redundant, encrypted command/control and video, automatic handoffs, Remote ID integration, and traceable connectivity performance data, strengthening the operational safety case for regulators.

2. How do BVLOS drones operate safely near active rail traffic and critical infrastructure?

BVLOS railway inspection operations rely on detailed mission planning, geofencing, defined flight corridors, real-time telemetry, and continuous command and control monitoring to maintain safe separation from rail traffic and infrastructure. Drones also use detect-and-avoid procedures, automated contingency responses, and Operators coordinate with railway control centers when required. Reliable multilink connectivity solutions such as Elsight’s Halo help maintain uninterrupted communications and situational awareness throughout long corridor inspections, even in challenging operational environments.

3. How does Halo secure railway inspection data and telemetry?

Halo secures railway inspection data and telemetry using AES-256-CBC encryption, secure VPN tunneling, multilink redundancy, and packet-level data splitting across multiple communication networks. Video streams, sensor data, command and control traffic, and telemetry are transmitted simultaneously across multiple available links, reducing vulnerability to interception, spoofing, and single-point failures. The platform continuously monitors link health and dynamically reroutes traffic if networks degrade or become unavailable.

4. How does Halo support long linear infrastructure inspections across remote areas?

Halo continuously bonds multiple available communication links, such as LTE, 5G, RF, and SATCOM, into a single resilient communication layer with dynamic traffic steering and seamless handoffs. If one network degrades, the system reroutes traffic across healthier available links without interrupting operations. This multilink redundancy is particularly important for railway inspections that traverse remote corridors and challenging environments.

5. What is the typical deployment timeline for implementing Halo on a rail inspection program?

Deployment timelines depend on the UAV platform, regulatory requirements, integration scope, and operational scale, but Halo is designed for rapid integration into existing drone inspection programs. Operators can scale deployments gradually from pilot programs to large corridor inspection networks while using Halo’s centralized connectivity and fleet management capabilities.