Part 135 vs Part 91: What Every Passenger Should Know

Part 135 vs Part 91: What Every Passenger Should Know

The distinction between Part 135 and Part 91 operations represents one of the most critical safety and legal concepts in aviation, yet many passengers remain unaware of these differences. Understanding these regulations can mean the difference between a legal, professionally conducted flight and an illegal operation that puts your safety at risk. This guide provides comprehensive information about both operational categories and explains why the distinction matters for your safety and legal protection.

Fundamental Regulatory Differences

Part 91: General Aviation Operations

Part 91 governs private, non-commercial aviation operations where no compensation changes hands. This includes:

Private Flying: Aircraft owners flying their own planes or their employees

Corporate Flight Departments: Companies operating aircraft exclusively for their own business purposes

Recreational Flying: Private pilots flying for personal enjoyment or transportation

Cost Sharing: Limited situations where private pilots can share certain costs with passengers

Key limitation: Part 91 operators cannot legally charge passengers for transportation services. If you're paying for a flight, it generally cannot be conducted under Part 91 regulations.

Part 135: Commercial On-Demand Operations

Part 135 governs commercial aviation operations including:

Charter Flights: On-demand passenger service for compensation

Air Taxi Operations: Scheduled and unscheduled passenger service with smaller aircraft

Cargo Operations: Commercial freight transportation

Commuter Airlines: Scheduled service with aircraft having 30 or fewer seats

Safety Standard Comparisons

Pilot Requirements

Part 91 Pilot Standards:

• Private Pilot License minimum for many operations
• No specific experience requirements beyond basic certification
• Recurrent training not federally mandated
• Medical certificates required but less frequent

Part 135 Pilot Standards:

• Airline Transport Pilot (ATP) license required for most captain positions (1,500+ flight hours minimum)
• Strict experience requirements including multi-engine and instrument time
• Mandatory recurrent training every 6-12 months
• More frequent medical examinations
• Specific training on aircraft type and company procedures
• Random drug and alcohol testing programs

The experience gap is substantial: A Part 135 captain typically has 5-10 times more flight experience than minimum Part 91 requirements.

Aircraft Maintenance Standards

Part 91 Maintenance:

• Annual inspections for most aircraft
• 100-hour inspections if carrying passengers for hire (which Part 91 operations shouldn't do)
• Owner-supervised maintenance programs
• Less stringent record-keeping requirements

Part 135 Maintenance:

• Continuous airworthiness programs with progressive inspections
• FAA-approved maintenance organization oversight
• Detailed maintenance tracking and record-keeping
• More frequent and comprehensive inspections
• Parts traceability and quality control requirements
• MEL (Minimum Equipment List) procedures for inoperative equipment

Operational Standards

Part 91 Operations:

• Pilot makes all operational decisions
• No formal dispatch system required
• Relaxed weather minimums in some cases
• Limited operational control oversight

Part 135 Operations:

• Formal operational control system
• Dispatch or flight following requirements for larger operations
• Stricter weather minimums
• Standardized operational procedures
• Flight and duty time limitations for crew
• Formal safety management systems for larger operators

Insurance and Legal Protections

Part 91 Insurance Considerations

Coverage Limitations: Private aircraft insurance may not cover commercial operations, potentially voiding coverage if passengers pay for flights

Passenger Protections: Limited legal protections for passengers who pay for unauthorized commercial operations

Liability Issues: Pilots and aircraft owners may face significant legal exposure for conducting unauthorized commercial operations

Part 135 Insurance Requirements

Mandatory Coverage: Federal regulations require substantial liability insurance

Commercial Policies: Insurance specifically designed for commercial passenger operations

Passenger Protections: Enhanced legal protections and recourse options for paying passengers

Professional Liability: Operators carry coverage appropriate for commercial operations

Legal Implications for Passengers

Illegal Charter Operations

Some operators attempt to circumvent Part 135 requirements through various schemes:

"Dry Leases": Passengers supposedly "lease" aircraft and hire pilots separately, though the operator arranges everything

"Cost Sharing": Misrepresenting commercial flights as shared expenses between friends

"Training Flights": Claiming passengers are receiving flight instruction when they're actually paying for transportation

"Aircraft Management": Complex arrangements that obscure the commercial nature of operations

These arrangements are typically illegal and offer no safety or legal protections.

Consequences of Illegal Operations

For Operators:

• Substantial FAA fines and penalties
• Criminal prosecution in some cases
• Certificate suspension or revocation
• Civil liability for accidents or incidents

For Passengers:

• No insurance coverage if accidents occur
• Limited legal recourse for service failures
• Potential complicity in federal regulatory violations

Recognizing Legitimate vs. Illegitimate Operations

Red Flags for Illegal Operations

Pricing: Rates significantly below market averages for comparable service

Documentation: Reluctance to provide Part 135 certificate numbers or operating authority

Payment Methods: Unusual payment arrangements or attempts to disguise commercial transactions

Advertising: Marketing "charter" services without mentioning Part 135 certification

Professional Standards: Lack of professional facilities, insurance documentation, or standardized procedures

Verifying Legitimate Part 135 Operations

Certificate Numbers: Request and verify Part 135 operating certificate numbers through FAA databases

Operations Specifications: Legitimate operators can provide their OpSpecs detailing authorized operations

Insurance Documentation: Professional operators readily provide current insurance certificates

Professional Facilities: Most legitimate operators maintain professional operations bases

Cost Implications

While Part 135 operations cost more than illegal alternatives, the price difference reflects real value:

Safety Investments: Higher costs fund enhanced pilot training, maintenance programs, and safety equipment

Insurance Coverage: Professional insurance protects passengers and operators

Regulatory Compliance: Proper certification and ongoing compliance represent significant investments

Professional Standards: Higher operational standards require greater resource investment

When Part 91 Operations Are Appropriate

Legitimate Part 91 situations include:

Corporate Flight Departments: Companies operating aircraft exclusively for their own business

Aircraft Ownership: Flying in aircraft you own or have a legitimate ownership interest in

Genuine Cost Sharing: Limited situations where private pilots can share actual costs with passengers

Non-Commercial Flights: Any flight where no compensation changes hands

Making Informed Decisions

Questions to Ask Potential Operators

1. "What is your Part 135 operating certificate number?"
2. "Can you provide your current Operations Specifications?"
3. "What insurance coverage do you carry for passenger operations?"
4. "What are your pilot qualification requirements?"
5. "How often do you conduct recurrent training?"

Evaluating Responses

Legitimate Part 135 operators will:

• Readily provide certificate information
• Proudly discuss their safety programs
• Explain their professional standards
• Provide comprehensive documentation
• Welcome verification of their credentials

Industry Trends and Future Developments

The charter industry continues evolving with new business models and technology:

Digital Platforms: Online charter marketplaces must ensure all listed operators maintain proper Part 135 certification

Fractional Ownership: These programs typically operate under Part 91 but serve owners rather than paying passengers

Jet Cards: Prepaid charter programs must utilize certified Part 135 operators for passenger flights

Conclusion

The distinction between Part 135 and Part 91 operations isn't just regulatory complexity—it represents fundamental differences in safety standards, legal protections, and professional accountability. When paying for air transportation, insisting on properly certified Part 135 operators protects your safety, ensures legal compliance, and supports the professional aviation industry.

While Part 135 operations cost more than illegal alternatives, this price difference reflects genuine value in enhanced safety standards, professional training, regulatory oversight, and legal protections. Understanding these differences empowers you to make informed decisions that prioritize safety while supporting legitimate, professional aviation operators.

Remember: if you're paying for air transportation, it should be conducted under Part 135 regulations. Anything else puts your safety, legal protection, and financial investment at risk. The aviation industry's excellent safety record depends on passengers choosing properly certified operators who prioritize safety through regulatory compliance and professional standards.