Electronic Flight Bag (EFB) in Part 135: Requirements, Classes, and Approval

If your Part 135 crews are using tablets in the cockpit without OpSpec A061, you may already have a compliance gap — even if the devices work perfectly. An electronic flight bag is a portable or installed electronic information system used by flight crews to replace traditional paper charts, performance tools, and manuals. For Part 135 operators, adopting an EFB is not as straightforward as handing pilots a tablet and downloading an app. This guide explains the EFB hardware classes (Class 1, 2, and 3), the Part 135 regulatory requirements for EFB approval under AC 120-76D, the OpSpec A061 authorization process, and the crew training and contingency planning steps operators must implement to achieve and maintain compliant EFB use.

What Is an Electronic Flight Bag?

An electronic flight bag is a portable or installed electronic information system used by flight crews to perform functions traditionally accomplished with paper — charts, performance calculations, weight-and-balance computations, manuals, and checklists. The term covers a wide spectrum, from a basic tablet running chart software to a fully installed avionics-grade display integrated with aircraft systems.

For commercial operators, an electronic flight bag is not a personal convenience tool. It is a regulated system that requires operational approval before it can replace required paper materials in the cockpit. The governing FAA guidance document is AC 120-76D, which provides the framework for EFB certification, airworthiness, and operational use. Note that the FAA issues revisions to advisory circulars periodically; operators should confirm the current revision letter with their Principal Operations Inspector (POI) and reference the most current version at time of implementation.

AC 120-76D applies specifically to operators under Part 91K, 121, 125, and 135. It does not apply to ordinary Part 91 general aviation flights. This distinction matters: a private pilot using a tablet for situational awareness under Part 91 faces no formal EFB approval requirement, but a Part 135 operator using that same tablet to replace required paper charts enters a different regulatory environment entirely. Understanding this scope is the first step toward compliance.

EFB Class 1, Class 2, and Class 3: Hardware Differences Explained

One of the most frequently misunderstood aspects of EFB guidance is the classification system. EFB Class 1, 2, and 3 designations describe the hardware platform and its installation context — not the software application running on it. A chart app does not determine the class. The physical device, how it is mounted, and whether it connects to aircraft systems determine the class. This distinction is critical because the more integrated the EFB is with aircraft systems, the greater the airworthiness scrutiny required.

Class 1 EFB

A Class 1 EFB is a fully portable, non-mounted device — typically a commercial off-the-shelf tablet or laptop. It is not physically attached to the aircraft and has no data connection to aircraft systems. The FAA generally treats a Class 1 device as a portable electronic device. The airworthiness burden is minimal, but operational approval is still required if the device replaces required paper materials under Part 135.

Class 2 EFB

A Class 2 EFB is portable but uses a mounting bracket, cradle, or data and power connection to the aircraft. The device itself may be a standard tablet, but its installation context introduces airworthiness considerations. The mount must not interfere with crew egress or flight controls, and any data interface between the EFB and aircraft systems requires careful evaluation. Aircraft connectivity provisions are a growing area of FAA attention for Class 2 installations.

Class 3 EFB

A Class 3 EFB is permanently installed equipment — part of the aircraft’s avionics suite. It is subject to the same airworthiness approval and certification standards as any other installed cockpit instrument. A Class 3 system is not a larger tablet bolted to the panel. It is aircraft-installed avionics, and its installation, modification, and maintenance follow the same regulatory path as other certified equipment.

Part 135 EFB Requirements: Why Approval Is Operational, Not Just Equipment-Based

Here is the misconception that creates the most compliance risk: buying a tablet does not equal compliance. Part 135 EFB approval is operational. The operator must demonstrate procedures, training, controls, and contingency plans — not simply present a receipt for hardware. This is fundamentally different from how many Part 91 pilots adopt tablets for personal use.

The specific authorization required before Part 135 operators can replace required paper charts and operational materials with digital equivalents is OpSpec A061. Note that specific OpSpec designators can vary by certificate and operation type; operators should confirm the exact authorization required with their POI. Without the appropriate authorization, your crews may be operating out of compliance, regardless of how capable the EFB hardware and software may be.

AC 120-76D establishes a risk-based approval model built around five pillars. The FAA expects operators to address each one before authorization is granted:

1. Operational procedures for in-flight use — documented procedures for how crews will use the EFB during all phases of flight, from preflight planning through shutdown.
2. Crew training — initial and recurrent training covering normal EFB operations, abnormal situations, and degraded-mode procedures.
3. Device management and update control — configuration control processes ensuring that software versions, chart databases, and app configurations are current and consistent across the fleet.
4. Backup sources for critical information — defined backup procedures for EFB failure, including when and how crews access alternate sources for charts, performance data, and other required information.
5. Compliance with the operator’s authorized methods and limitations — the EFB program must fit within the operator’s existing operations specifications and approved procedures.

Even a portable Class 1 EFB requires operational approval if it replaces required paper materials. The FAA does not exempt a device from scrutiny based on form factor alone. And because AC 120-76D applies to Part 91K, 121, 125, and 135 — not ordinary Part 91 flights — the compliance bar is significantly higher than what many operators initially expect.

The OpSpec A061 Authorization Process: A Practical Overview

For operators asking how to get EFB approval under Part 135, the authorization process can be summarized in six practical steps. This is a general overview — operators should reference AC 120-76D and coordinate with their Principal Operations Inspector (POI) for certificate-specific guidance.

1. Document your EFB hardware and software configuration. Identify the device class, operating system, EFB applications, and any aircraft interfaces. This establishes the baseline for your approval request.
2. Develop written procedures for EFB use in all phases of flight. Cover preflight setup, in-flight operations, approach and landing procedures, and post-flight data management.
3. Establish a crew training program covering normal and abnormal EFB operations. Training must address device operation, database currency verification, and degraded-mode procedures.
4. Define backup and contingency procedures for EFB failure. Specify when paper backups are required, how crews access them, and what constitutes an EFB failure requiring reversion to alternate sources.
5. Create an update management plan for software, digital aeronautical charts, and databases. Database currency is not optional — crews must have a reliable process to verify that chart and navigation data are current before each flight.
6. Submit to your FSDO or principal inspector for review and authorization. Expect a thorough review of your documentation, procedures, and training program before authorization is issued.

One point that catches many operators off guard: EFB approval is maintenance-intensive post-authorization. Software updates, chart database currency cycles, and procedural changes all require ongoing configuration control. OpSpec A061 is not a one-time checkbox.

For a deeper dive into Part 135 regulatory compliance and training program design, see the CTS Part 135 Training package.

Electronic Flight Bag Training Requirements for Part 135 Crews

Industry consensus frames EFB success as a human factors and procedures challenge, not primarily a technology selection decision. The most capable hardware and software in the cockpit will not protect an operator if crews are not trained to use the system correctly — and to revert safely when it fails.

Essential training topics for Part 135 EFB authorization include:

• EFB initialization and preflight checks
• Chart and database currency verification
• Power management and battery contingency
• Mounting and glare considerations
• Lost-device and degraded-mode procedures
• When paper backups are required and where they are stowed

Training delivery matters as much as training content. E-learning modules work well for device familiarization, recurrent policy updates, scenario-based failure training, and quick-reference policy acknowledgments. These formats allow Part 135 operators to deliver standardized training across geographically dispersed crews without pulling everyone into a classroom.

For operators using multiple device types or app versions — which is increasingly common in mixed fleets — training must address configuration control so crews know which functions are approved on which devices. A crew member approved to use performance calculations on one app version may not be authorized to use that same function on a different version or device.

The core principle is straightforward: crews must be trained both on how to operate the EFB and how to revert safely if it fails, freezes, loses power, or cannot access current data. Crew standardization depends on covering both sides of that equation.

Common EFB Misconceptions in Part 135 Operations

“Any tablet is automatically approved for Part 135 use.”
Incorrect. Approval depends on the operator’s authorization, documented procedures, and the specific use case — not the hardware purchase. A tablet without the appropriate OpSpec authorization is not a compliant EFB.

“EFB classes describe the app.”
No. EFB Class 1, 2, and 3 designations refer to the hardware platform and installation context. Application functions are addressed separately in operational guidance under AC 120-76D.

“Portable means no oversight.”
Even portable EFBs require operational approval when they replace required paper materials. A Class 1 device used to display digital aeronautical charts in lieu of paper charts falls under Part 135 EFB requirements.

“Installed EFBs are just bigger tablets.”
Class 3 systems are treated as installed aircraft equipment, subject to full airworthiness approval. They follow the same certification and maintenance standards as other cockpit avionics.

“Once approved, no training updates are needed.”
EFB approval is maintenance-intensive. Software versions change, chart databases require regular currency updates, app interfaces evolve, and company procedures are revised. Recurrent training must keep pace with these changes.

Staying Compliant: EFB Update Management and Contingency Planning

Obtaining OpSpec authorization is not the finish line. Ongoing compliance requires active management across several dimensions:

• Software and app version control across the fleet. Every device in the operation should run approved and consistent software versions. Unauthorized updates or mixed versions create configuration control risks.
• Chart and navigation database currency checks. Database currency must be verified before each flight. Expired charts or navigation data can compromise safety and regulatory standing.
• Procedure updates when vendor apps change features or interfaces. App updates can alter workflows, relocate functions, or change display formats. Procedures and training must be updated accordingly.
• Contingency plans for device failure, loss, or data corruption in flight. Backup procedures should be specific and practiced — not theoretical. Crews need to know exactly where alternate information sources are and how to access them quickly.
• Periodic training refreshers. Recurrent training should cover procedural changes, new software features, and lessons learned from operational experience.

A growing area of FAA attention involves aircraft connectivity provisions — particularly when EFBs receive data from onboard systems or external networks. As more operators move to connected EFB workflows, data integrity and cybersecurity considerations are becoming part of the compliance conversation. Part 135 operators should monitor developments in this area and be prepared to update their programs as FAA guidance evolves.

How to Build a Part 135 Electronic Flight Bag Training Program That Works

EFB adoption in Part 135 is a training and procedures challenge. The operators who succeed treat their electronic flight bag program as an ongoing commitment to crew standardization, not a one-time equipment purchase. Start with AC 120-76D as the regulatory foundation — it provides the framework for everything from hardware classification to operational approval.

Build your training around both normal operations and realistic failure scenarios. Crews who have practiced degraded-mode procedures in training will handle device failures in flight with far less disruption. Use e-learning for scalable, recurrent training delivery — it is particularly effective for device familiarization, policy acknowledgments, and scenario-based exercises that reinforce contingency planning skills.

Treat EFB compliance as an ongoing program, not a project with a completion date. Software changes, database cycles, and procedural updates will demand continuous attention. Purpose-built EFB training courses and e-learning modules can accelerate this process and standardize crew knowledge across your operation.

Ready to build or upgrade your Part 135 EFB training program? Explore the CTS Electronic Flight Bag (EFB) Training Course to give your crews the regulatory knowledge and practical skills they need for compliant EFB operations.

Related Reading

• FAA Advisory Circulars Library
• EFB (Electronic Flight Bag) Explained — Aviatize Aviation Glossary
• Jeppesen Charts Explained: Part 91 & Part 135 Pilot Guide — CTS

Related CTS Training

• Part 135 Training
• IS-BAO/PART 91 Training
• EFB Training Course