Avionics - Lightning Protection

Avionics - Lightning Protection is an in-depth, four-and-one-half-day course for engineers concerned with lightning protection design and certification of avionics and other electrical systems. The course includes a detailed study of lightning indirect effects and coupling mechanisms, analysis and testing of transient levels, specific protection-design scenarios and techniques, and a thorough discussion of certification plans and verification-test methods and procedures. Emphasis is given to the protection of flight-critical and flight-essential systems.

For registration form and schedule, click below.


Students are required to have completed the primary course, Lightning Protection of Aircraft, offered by Lightning Technologies, Inc., or have prior related experience and the approval of the lead instructor.

Course Outline

Role and Contents of Airworthiness Regulations

  • FAA Regulations
    • Transport Category, FAR 25.1309, 25.1316 (Proposed)
    • General Aviation Category, FAR 23.1309
    • Normal Rotorcraft, FAR 27.1309D
    • Transport Rotorcraft, FAR 29.1309H
    • Special Conditions and Issue Papers
  • U.S. MIL-STD 1795A
  • FAA Compliance Guidelines
    • Protection of Aircraft Electrical/Electronic Systems Against the Indirect Effects of Lightning, FAA AC-20-136
  • Industry Test Standards
    • SAE AE4L Committee: AE4L-81-2, Yellow Book and AE4L-87-3, Orange Book
    • RCTA DO-160 Section 22, Change Notice 2
    • EUROCAE ED-14 Chapter 22, Change Notice 2
    • Airframe Manufacturer Requirements
  • External Environment Standards and Relationships to the Natural Environment

Identification of Flight-Critical and Flight-Essential Systems

  • FAA Definitions
  • Importance of Programwide Cooperation

Lightning Interaction with Electrical and Avionics Systems

  • Indirect-effects Coupling Mechanisms
  • Susceptibility of and Effects on Avionics and Electrical Systems
  • Special Considerations for Composite Aircraft
  • Multiple-burst and Multiple-stroke Considerations

Protection Design

  • Damage and Upset Tolerance
  • Shielding, Cable Routing, Circuit Wiring-Type Selection, Terminal Protection and Dielectric Isolation
  • Hardware and Software Techniques to Improve Circuit Tolerance
  • Coordination of Protection Methods at Interconnected LRUs
  • Isolation vs. Terminal Protection Devices
  • Altitude and Temperature Effects on Protection Performance
  • Design Pitfalls

Treatment of Flight-Essential vs. Flight-Critical Functions

Preparation of Certification Plans

  • Purpose
  • Who Should Do Them
  • Examples

Equipment Transient Design Levels (ETDLs) and Transient Control Levels (TCLs)

  • Definitions and Examples
  • Methods of Selecting ETDLs and TCLs
  • "Box" and "System" Levels
  • Defining Margins
  • Pin Specifications
  • Multiple-stroke and Multiple-burst Considerations
  • Pitfalls in ETDL Selection

Preparation of Test Plans

  • Full Vehicle Tests
  • Individual LRUs
  • Interconnected Systems

Test Equipment and Facility Requirements

Verification of TCLs

  • Full-vehicle Test Methods and Examples
  • Analysis Methods and Examples
  • Similarity with Previous Test Data

Verification of ETDLs

  • Damage Tolerance of LRUs
    • Pin Injection Tests
  • Cable-bundle Tests
  • Damage and Upset Tolerance of Interconnected Systems
    • Cable-bundle Tests
    • Transformer-coupling Tests
    • Ground-Injection Tests

Laboratory Demonstrations

  • Selected Verification Test Methods and Setups

Management of Successful Indirect-Effects Protection and Certification Programs

Areas of Uncertainty and Research

Future Trends in Lightning Protection

Sources of Additional Information