When Is SMS Required for Part 135 Operators?

A common and important question in business aviation is when a Safety Management System in business aviation becomes a regulatory requirement for Part 135 operators. The short answer is that an SMS is not universally required for all Part 135 certificate holders today, but it will be for many operators in the near future. The Federal Aviation Administration has established a phased approach that ties SMS requirements to the size and complexity of the operation, with a clear end state in mind.

Understanding when an SMS is required, and what is expected when that requirement applies, is critical for Part 135 operators making long-term compliance and safety planning decisions. This article explains the regulatory framework, clarifies common misconceptions, and outlines what effective implementation looks like in real-world operations.

What Does “SMS Required” Mean Under Part 135?

A Safety Management System is a formal, organization-wide approach to managing safety risk. In the United States, SMS requirements are established in 14 CFR Part 5 and are aligned with international standards developed by the International Civil Aviation Organization under ICAO Annex 19.

When an SMS is “required” for a Part 135 operator, it means the operator must have an SMS that meets the applicable elements of Part 5 and is acceptable to the Federal Aviation Administration. This goes beyond having informal safety practices or a collection of manuals. It requires a structured system with defined policies, processes, accountability, and continuous oversight.

When Is SMS Required for Part 135 Operators Today?

As of now, SMS is required for certain Part 135 operators based on operational complexity and scope. The FAA initially focused on larger, more complex operations, particularly those conducting commuter or on-demand operations with higher passenger exposure.

Historically, SMS requirements were first applied to Part 121 air carriers and then extended incrementally to other certificate holders. For Part 135, the FAA adopted a phased implementation strategy rather than an immediate across-the-board mandate.

This approach recognizes that Part 135 operators range from single-aircraft charter operators to complex fleets operating across multiple bases with varied mission profiles. The regulatory burden and implementation expectations scale accordingly.

The 2027 SMS Mandate for Part 135 Operators

The most significant milestone for Part 135 operators is the FAA’s planned SMS mandate with a compliance deadline in 2027. Under this rulemaking, most Part 135 certificate holders will be required to implement an SMS that complies with Part 5.

While specific applicability details are defined in the final rule and associated guidance, the intent is clear. SMS will become a standard requirement for Part 135 operations, similar to how it is already treated under Part 121.

For many operators, this means SMS planning should be treated as a near-term requirement rather than a distant future consideration. Waiting until the deadline approaches can create unnecessary operational and organizational strain.

How SMS Requirements Differ Between Part 135 and Other Parts

One source of confusion is the assumption that SMS requirements are identical across all operational parts. While Part 5 provides a common framework, how SMS is applied varies by operational context.

In Part 91 operations, SMS is generally voluntary, except for certain activities such as commercial air tours. In Part 145 repair stations, SMS requirements are evolving, with increased alignment to international expectations and customer-driven requirements.

Part 135 sits between these two extremes. It involves commercial operations with paying passengers, but often with fewer resources and smaller organizational structures than Part 121 carriers. The FAA’s SMS expectations reflect this balance by emphasizing scalability and proportionality.

A more detailed comparison of these differences is often addressed in guidance that explains how SMS applies differently to Part 91, Part 135, and Part 145 operators.

Why SMS Matters Specifically for Part 135 Operations

Part 135 operations present a unique risk environment. Flights are often conducted into a wide range of airports, under varying weather conditions, and with tight schedules driven by customer demand. Crews may operate with limited support infrastructure compared to airline environments.

An effective Safety Management System in business aviation provides a structured way to identify and manage these risks before they result in incidents or accidents. It shifts safety oversight from reactive event response to proactive hazard identification and trend analysis.

From a regulatory perspective, SMS also gives the FAA greater confidence that an operator can manage safety risk systematically as operations evolve.

What Part 5 Actually Requires From a Part 135 SMS

Part 5 is built around four core components: Safety Policy, Safety Risk Management, Safety Assurance, and Safety Promotion. These elements are often referred to as the four pillars of SMS.

For a Part 135 operator, compliance does not mean creating unnecessary bureaucracy. It means demonstrating that the organization has:

• Clear safety accountability and leadership commitment

• A structured process to identify hazards and assess risk

• Methods to verify that risk controls are effective

• Training and communication that support a positive safety culture

Understanding what Part 5 requires, as opposed to what operators assume it requires, is essential to building a system that is both compliant and usable.

Practical Examples of SMS in Part 135 Operations

In day-to-day operations, SMS shows up in practical and often routine activities. A pilot submits a hazard report after encountering recurring runway contamination at a destination airport. That report is reviewed, risk is assessed, and mitigations are implemented, such as revised destination criteria or updated crew guidance.

Another example might involve trend analysis of unstable approaches across a fleet. Rather than treating each event in isolation, the SMS allows the operator to identify systemic contributors and adjust procedures or training accordingly.

These are not abstract concepts. They are operational tools that directly support safer decision-making.

Common Misunderstandings About SMS Requirements

One common misconception is that SMS is only required once the FAA formally approves it. In reality, compliance is based on having an acceptable system in place that meets Part 5 requirements, not on waiting for a specific approval milestone.

Another misunderstanding is that SMS replaces regulatory compliance. SMS does not replace compliance with Part 135 operating rules. It complements them by providing a framework to manage safety risk within those rules.

Some operators also assume that SMS is only about documentation. While documentation is necessary, the FAA’s primary focus is on how the system functions in practice.

What “Good” Looks Like for a Part 135 SMS

A well-implemented SMS is integrated into normal operations. Safety reporting is easy and encouraged. Risk assessments are practical and timely. Management uses safety data to inform decisions rather than treating SMS as a separate administrative exercise.

From an oversight perspective, a good SMS allows an operator to demonstrate control over its safety risks. This becomes increasingly important as operations grow or change.

Auditors and inspectors often look for evidence that SMS processes are actually used and understood throughout the organization, not just described in manuals.

The Role of Technology in Supporting SMS

Modern SMS platforms can significantly reduce the administrative burden of compliance. Technology supports consistent data collection, structured risk assessments, and meaningful trend analysis across the operation.

For Part 135 operators, this is particularly valuable given limited staff resources. Technology helps ensure that SMS processes remain sustainable over time and do not rely on individual memory or informal tracking.

While technology does not replace leadership or accountability, it can enable an SMS to function as intended under Part 5.

A Forward-Looking Perspective for Part 135 Operators

The question of when SMS is required for Part 135 operators is becoming less about if and more about readiness. With a 2027 mandate on the horizon, SMS should be viewed as a foundational element of modern Part 135 operations.

Operators that approach SMS early and deliberately are better positioned to integrate it effectively, rather than treating it as a last-minute compliance task. As regulatory expectations continue to align with international standards, SMS will remain a central component of safety oversight in business aviation.