Low Intensity Obstruction Light
For structures where low-intensity visual identification is applicable.
View Details Obstruction & Identification Lighting
Medium Intensity Obstruction Light (Type A/B/C)
Enhanced visual identification for towers, masts and tall structures
Medium-intensity obstruction lighting provides enhanced visual identification of structures where increased conspicuity is required by the applicable aviation lighting configuration. Configured to structure height, location, operating conditions and aviation authority requirements.
Supplied by Precision AGL Solutions
Product Overview
Medium Intensity Obstruction Light (Type A/B/C)
What It Is
The light provides a higher level of visual identification than low-intensity obstruction lighting for structures requiring enhanced visibility.
Depending on classification, it may operate with steady or flashing output and may form part of a multi-level obstruction-lighting arrangement.
A complete installation may include multiple lights at defined elevations so the obstacle can be identified from relevant viewing directions.
How We Supply It
Precision AGL Solutions supplies medium-intensity obstruction lights for towers, masts, communication structures, industrial installations and other tall structures that may present an aviation obstacle.
Type A, Type B or Type C configurations may be selected, with final optical and operating characteristics determined by the project specification. We support selection by optical output, operating mode, mounting, electrical supply and monitoring requirements.
Applications
Where Medium-Intensity Lights Are Used
Communication towersCommunication towers and antenna structures.
Telecom mastsTelecommunications masts.
Utility structuresTall utility and infrastructure structures.
Industrial towersIndustrial towers and elevated structures.
Airport-adjacentAirport-adjacent buildings and installations.
Tall buildingsTall buildings and rooftop structures.
CranesCranes and other applicable temporary structures.
Enhanced visibilityStructures requiring enhanced aviation visibility.
Replacement & modernizationExisting obstruction-lighting systems.
The final lighting arrangement should be established from the approved aviation lighting assessment and applicable regulatory requirements.
Type A / Type B / Type C Configuration
Classification Is Application-Specific
The Configuration May Depend On
- Structure height
- Structure location
- Airspace and surrounding aviation activity
- Day/night operating requirements
- Required light colour
- Required luminous intensity
- Flashing or steady operation
- Lighting levels on the structure
- Visibility and environmental conditions
- Applicable aviation authority requirements
Do Not Assume from the Name
Medium-intensity classifications should be selected according to the applicable aviation requirements.
Type A, Type B and Type C requirements should not be assumed solely from the product name. The final configuration should be confirmed against the approved project specification.
ICAO Classification
What Type A, Type B and Type C Mean
| ICAO Type | Colour | Mode | Typical peak intensity | Typical use |
|---|---|---|---|---|
| Type A | White | Flashing (20–60 per minute) | About 20,000 cd by day and at twilight, reduced to about 2,000 cd at night | Day and night marking where strong daytime conspicuity is needed |
| Type B | Red | Flashing (20–60 per minute) | About 2,000 cd | Night marking, with day marking by paint or other means |
| Type C | Red | Steady (fixed) | About 2,000 cd | Night marking where a steady red light is accepted |
Where They Are Used
ICAO uses medium-intensity lights for structures roughly in the 45 m to 150 m range, with low-intensity lights below that and high-intensity lights above it or where more conspicuity is needed. On tall structures, lights are placed at levels between the top and ground at about equal intervals, normally not more than about 52 m apart. Flashing lights on one structure flash together.
FAA Equivalents
FAA equipment is specified in AC 150/5345-43J as L-865 (white flashing, medium intensity) and L-864 (red flashing). FAA lighting systems are laid out under AC 70/7460-1N. FAA and ICAO systems are not interchangeable, so follow the authority for the project.
Values are typical ICAO figures from Annex 14, Vol. I, Chapter 6. Confirm intensities, flash rates and spacing against the edition and national rules in force, including DGCA India requirements and the NOC conditions for the structure.
Key Features
What the Product Category Offers
- Medium-intensity aviation obstruction lighting
- Type A, Type B or Type C configurations, as applicable
- Suitable for towers, masts and tall structures
- Steady or flashing operation depending on classification
- High-visibility optical output
- LED-based configurations where applicable
- Suitable for new installations and retrofit projects
- Structure-mounted installation
- Project-specific mounting options
- Outdoor environmental construction
- Optional monitoring and status interfaces
- Suitable for integration into coordinated obstruction-lighting systems
Typical Technical Data
Confirm Parameters Against the Selected Configuration
| Parameter | Typical Specification |
|---|---|
| Light Type | Medium-intensity obstruction light |
| Configuration | Type A / Type B / Type C, as applicable |
| Light Source | LED or approved source, configuration dependent |
| Colour | Aviation-specified colour |
| Intensity | Classification and project dependent |
| Operation | Steady or flashing |
| Flash Pattern | Configuration dependent |
| Power Supply | Model dependent |
| Power Consumption | Model dependent |
| Monitoring | Local or remote monitoring, where specified |
| Mounting | Structure, mast, tower or project-specific bracket |
| Dimensions | Model dependent |
| Environmental Protection | Outdoor-rated construction, configuration dependent |
| Operating Temperature | Model dependent |
| Cable / Connection | Project-specific interface |
Exact photometric performance, electrical ratings, flash characteristics, dimensions and environmental specifications should be confirmed against the selected product configuration.
Optical Performance
Enhanced Identification from Aircraft Viewing Directions
Optical Characteristics May Include
- Defined luminous intensity
- Aviation-specified colour
- Horizontal light distribution
- Vertical light distribution
- Steady or flashing operation
- Controlled optical output
- Consistent performance across the operating range
Matching Optics to the Structure
The optical arrangement should be selected to suit the structure and required obstruction-lighting configuration.
For structures with complex geometry, multiple lighting levels or significant changes in elevation, the layout should be reviewed as part of the overall aviation obstruction assessment.
Flashing & Steady Operation
Operating Characteristic Follows the Classification
The Operating Characteristic Can Be Determined By
- Aviation authority requirements
- Structure classification
- Structure height
- Day/night requirements
- Required conspicuity
- Coordination with other obstruction lights
- Project control philosophy
Flash Pattern & Timing
Depending on the applicable Type A/B/C configuration, lights may provide steady-burning or flashing operation.
Where flashing lights are specified, the required flash pattern, timing and synchronization should be confirmed during technical selection.
Multi-Level Structure Lighting
Lights at Different Elevations
Top-Level LightsHighest lighting level
Intermediate-Level LightsMid-structure levels
Lower-Level LightsLower lighting levels
Control & Monitoring SystemCoordinates and supervises all levels
Tall towers, masts and other structures may require multiple lights at different elevations. The number and position of levels depend on the approved obstruction-lighting design. Positions should be selected so that structural elements do not unnecessarily obstruct the intended optical coverage and the structure remains identifiable from relevant directions.
Synchronization
Coordinated Operation of Flashing Lights
System-Level Configuration Can Include
- Flash synchronization
- Common timing reference
- Local control
- Central controller
- Status monitoring
- Fault indication
- Remote alarm interfaces
When It Is Required
Where multiple flashing obstruction lights are installed on the same structure, coordinated operation may be required.
Synchronization requirements depend on the selected lighting classification and project control philosophy.
Monitoring & Status Indication
Configured Where Required
Monitoring May Include
- Light operating status
- Power status
- Controller status
- Flashing status
- Individual light fault indication
- Communication status
- Remote alarm output
Integration
Monitoring architecture should be coordinated with the site's electrical, SCADA, building-management or aviation infrastructure where applicable.
Electrical Configuration
Selected to Site Supply and Control System
Important Considerations
- Supply voltage
- AC/DC configuration
- Power consumption
- Surge protection
- Cable entry
- Connector arrangement
- Control interface
- Monitoring interface
- Local isolation
- Earthing arrangements
Complete Installation
The complete electrical installation should be designed to suit the structure, site conditions and applicable electrical requirements.
Automatic Control
Optional Integration with Control Equipment
Control Functionality May Include
- Automatic day/night operation
- Photocell input
- Scheduled operation
- Flash control
- Synchronization
- Fault monitoring
- Remote status indication
Mixed Light Types
Where multiple light types or intensities are used on the same structure, the control system should coordinate their operation according to the approved lighting design.
Mounting Arrangements
Supplied for a Range of Structures
Typical Mounting Arrangements
- Tower platforms
- Mast structures
- Structural brackets
- Rooftop equipment platforms
- Vertical support structures
- Custom project mounting assemblies
Secure and Accessible
Mounting hardware should provide secure mechanical support while maintaining the required optical orientation.
The mounting arrangement should also allow suitable access for inspection and maintenance.
Environmental Performance
Demanding Outdoor Conditions
Tower and Mast Exposure
- Wind
- Rain
- Dust
- Solar radiation
- Temperature cycling
- Vibration
- Moisture
- Coastal environments
- Industrial pollution
Materials
The selected enclosure, optical window, fasteners and mounting materials should be appropriate for the installation environment.
For coastal or highly corrosive locations, suitable corrosion-resistant materials and protective finishes should be considered.
Installation Considerations
Confirm Before Installation
Confirm
- Approved obstruction-lighting layout
- Required Type A/B/C classification
- Light locations and elevations
- Optical orientation
- Structure geometry
- Mounting details
- Cable routes
- Electrical supply
- Control architecture
- Monitoring requirements
- Surge and lightning protection
- Maintenance access
Approved Drawings
The obstruction-lighting system should be installed in accordance with the approved project drawings and applicable aviation requirements.
Commissioning
Verify Operation Against the Approved Configuration
- Inspect light mounting and orientation
- Verify electrical connections
- Confirm supply voltage and protection
- Test steady or flashing operation
- Verify colour and optical output
- Check flash characteristics where applicable
- Verify synchronization between lights where required
- Test monitoring and alarm functions
- Check automatic control or photocell operation
- Record commissioning results
Where required by the project, photometric measurements and functional tests should be performed using suitable calibrated equipment.
Maintenance
Reliable Operation, Manageable Maintenance
Routine Maintenance May Include
- Visual inspection
- Cleaning of optical surfaces
- Checking mounting hardware
- Inspection of cable entries
- Checking electrical connections
- Functional testing
- Verification of monitoring signals
- Inspection for moisture ingress
- Checking structural mounting components
- Replacement of damaged or degraded components
LED Systems
LED-based systems can reduce routine light-source replacement requirements, although periodic inspection and system testing remain important.
Troubleshooting
Condition, Cause and Recommended Check
| Condition | Possible Cause | Recommended Check |
|---|---|---|
| Light not operating | Power or control failure | Check supply, protection and control circuit |
| Reduced optical output | Dirty lens or optical degradation | Inspect and clean optical surface |
| Incorrect flashing | Configuration or controller issue | Check flash settings and controller |
| Lights not synchronized | Timing/control communication fault | Check synchronization circuit |
| Monitoring alarm active | Light, power or communication fault | Review system status and fault indication |
| Intermittent operation | Supply or connection problem | Inspect cable, terminals and connectors |
| Moisture inside enclosure | Seal or cable-entry problem | Inspect enclosure and sealing |
| Light movement | Loose or unsuitable mounting | Inspect and secure mounting assembly |
Replacement & Retrofit
Upgrading Obsolete or Hard-to-Maintain Systems
Retrofit Assessment Should Consider
- Existing light classification
- Required intensity
- Existing mounting locations
- Structure geometry
- Supply voltage
- Control system
- Monitoring interface
- Cable arrangement
- Flash synchronization
- Current aviation requirements
Not by Physical Fit Alone
Medium-intensity lights are suitable for upgrading existing systems where older equipment has become obsolete, difficult to maintain or incompatible with current project requirements.
A replacement should be selected on the complete optical and operational requirements rather than physical compatibility alone.
Procurement Checklist
Information to Provide with Your Request
- Structure type
- Overall structure height
- Structure location
- Type A, B or C requirement, if already established
- Applicable aviation authority
- Required light colour
- Steady or flashing operation
- Required flash characteristics
- Number of lighting levels
- Quantity of lights
- Available power supply
- Existing control system
- Monitoring requirements
- Mounting arrangement
- Environmental conditions
- New installation or replacement project
This information helps determine the appropriate medium-intensity obstruction-lighting arrangement.
Standards & References
Confirm Applicable Requirements
References
- ICAO Annex 14, Vol. I, Chapter 6: obstacle lighting and marking (Tables 6-1 and 6-3)
- ICAO Doc 9157 Part 4: visual aids
- FAA AC 70/7460-1N: obstruction marking and lighting
- FAA AC 150/5345-43J: specification for obstruction lighting equipment (L-864, L-865)
- DGCA India requirements and NOC conditions for the structure
Jurisdiction-Dependent
Requirements vary with the jurisdiction, structure type, location and aviation authority. Confirm the edition and any national differences before procurement, and base the final design on the approved obstruction-lighting assessment.
Documentation
Depending on the Selected Configuration
- Product datasheet
- Photometric information
- Electrical specifications
- Mounting drawings
- Installation instructions
- Control and monitoring information
- Wiring diagrams
- Maintenance recommendations
- Compliance documentation, where applicable
Why Precision AGL Solutions
Dependable Visual Identification and Obstruction Marking
We supply aviation lighting equipment for airport, airfield, tower and aviation-infrastructure projects. Our obstruction-lighting solutions can support:
- New tower and mast installations
- Airport-adjacent infrastructure
- Obstruction-lighting upgrades
- Replacement of legacy equipment
- Multi-level lighting arrangements
- Monitoring and control integration
- Project-specific mounting requirements
- Technical documentation and selection support
FAQ
Medium Intensity Obstruction Light (Type A/B/C) — Frequently Asked Questions
What is a medium-intensity obstruction light?
A medium-intensity obstruction light gives a higher level of visual identification than low-intensity lighting for structures that need enhanced visibility. Depending on classification it may operate steady or flashing and may form part of a multi-level arrangement. Typical applications are communication towers, telecom masts, tall utility and industrial structures, tall buildings and cranes.
What do ICAO Type A, B and C mean?
Type A is white and flashing at 20 to 60 flashes per minute, with a peak intensity of about 20,000 cd by day and at twilight, reduced to about 2,000 cd at night. Type B is red and flashing at 20 to 60 per minute at about 2,000 cd, for night marking with day marking by paint or other means. Type C is red and steady at about 2,000 cd, for night marking where a steady red light is accepted.
What structure heights use medium-intensity lighting?
ICAO uses medium-intensity lights for structures roughly in the 45 m to 150 m range, with low-intensity lights below that and high-intensity lights above it or where more conspicuity is needed. These are typical figures from Annex 14 Volume I Chapter 6, so confirm them against the edition and national rules in force, including DGCA India requirements and the NOC conditions for the structure.
How do FAA and ICAO systems differ?
FAA equipment is specified in AC 150/5345-43J as L-865 (white flashing, medium intensity) and L-864 (red flashing), and FAA lighting systems are laid out under AC 70/7460-1N. FAA and ICAO systems are not interchangeable, so follow the authority for the project. The classification should not be assumed from the product name and must be confirmed against the approved project specification.
How are lights arranged on a tall structure?
On tall structures, lights are placed at levels between the top and ground at about equal intervals, normally not more than about 52 m apart, and flashing lights on one structure flash together. The number and position of levels come from the approved obstruction-lighting design, and positions should avoid structural elements blocking the intended optical coverage.
When is flash synchronization needed?
Where multiple flashing obstruction lights are installed on the same structure, coordinated operation may be required, depending on the selected classification and the project control philosophy. A system can include a common timing reference, local control or a central controller, status monitoring and fault indication, and the required flash pattern, timing and synchronization should be confirmed during technical selection.
What monitoring options are available?
Monitoring may cover light operating status, power status, controller status, flashing status, individual light fault indication, communication status and remote alarm output. The architecture should be coordinated with the site electrical, SCADA, building-management or aviation infrastructure where applicable.
What electrical and control arrangements are used?
The configuration is selected to suit the site supply and control system, covering supply voltage, AC or DC configuration, surge protection, cable entry, local isolation and earthing. Control can include automatic day/night operation, photocell input, scheduled operation, flash control and fault monitoring. Where several light types or intensities are used on the same structure, the control system should coordinate them according to the approved lighting design.
How is a medium-intensity system commissioned?
Verify mounting and orientation, electrical connections, supply voltage and protection, then test steady or flashing operation, colour and optical output, flash characteristics where applicable, and synchronization between lights where required. Test monitoring and alarm functions and photocell operation, and record the results. Where the project requires it, use calibrated equipment for photometric measurements.
What are the common faults?
A light that is not operating usually points to a power or control failure, and reduced optical output to a dirty lens or optical degradation. Incorrect flashing suggests a configuration or controller issue, lights out of step suggest a timing or control communication fault, and intermittent operation suggests a supply or connection problem. Moisture inside the enclosure indicates a seal or cable-entry problem, and movement of the light a loose or unsuitable mounting.
What should be provided when requesting medium-intensity lights?
Provide the structure type, overall height and location, the Type A, B or C requirement if already established, the applicable aviation authority, the required colour, steady or flashing operation and flash characteristics, the number of lighting levels and quantity of lights, the power supply, existing control system, monitoring requirements, mounting arrangement, environmental conditions and whether it is new or a replacement. A replacement should be selected on the complete optical and operational requirements rather than physical compatibility alone.
Procurement Information for Indian Projects
Indian public tenders commonly ask for the documents below. State which ones your tender requires when you send the enquiry, so they are covered in the quotation.
- Manufacturer / OEM authorisation
- Country of origin and local-content declaration (for Make in India purchase preference)
- Type-test and routine-test certificates, and the FAA / ICAO / IEC compliance documents named in the specification
- Datasheets, drawings and installation instructions
- Warranty, delivery period and spares support
- GeM catalogue or tender-portal requirements, where applicable
Request Obstruction-Lighting Configuration
Planning obstruction lighting for a tower, mast, communication structure or tall airport-adjacent installation? Send us the structure height, location, required Type A/B/C classification, light operating mode, number of lighting levels, power supply and applicable project specification. We can review the application and recommend the appropriate Medium Intensity Obstruction Light configuration, including optical characteristics, mounting, control and monitoring interfaces.
Request obstruction-lighting configuration and technical documentation from Precision AGL Solutions.
- Emailprecisionaglsolutions@gmail.com
- Websiterahulsharmaagl.in
- LinkedInPrecision AGL Solutions
- Phone+91 98214 96412
Engineering Note
Medium-intensity obstruction-light classification, luminous intensity, colour, flash characteristics, lighting levels and operating requirements are application- and authority-dependent. Exact product parameters should be confirmed against the approved aviation lighting assessment and current requirements applicable to the project before procurement or installation.
Product Disclaimer
Product availability, configuration, dimensions, electrical characteristics, photometric performance, certifications and compliance status depend on the selected manufacturer and project specification. The technical values published on this page should not be treated as a substitute for the manufacturer's current approved Technical Data Sheet.
Final selection shall be based on the approved project specification, applicable aviation standards, authority requirements, manufacturer documentation and site conditions. Use of this page is also subject to the Legal Notice, Disclaimer & Terms of Use.
Standards and editions referenced on this site are listed on the Standards Reference page.