The decision to operate aircraft for charter or to place a privately owned aircraft under professional management introduces regulatory and contractual complexity that extends well beyond standard business operations. The Federal Aviation Administration draws sharp distinctions between private operations conducted under Part 91 of the Federal Aviation Regulations and commercial operations conducted under Part 135, and the legal, operational, and financial implications of crossing that line are substantial. For aircraft owners, the management agreement with an operating company defines who controls the aircraft, who bears responsibility for regulatory compliance, who employs the crew, and who assumes liability when things go wrong. For charter operators, the certificate they hold and the operational framework they maintain determine their legal authority to conduct revenue flights and their exposure to regulatory enforcement. Understanding these frameworks is essential for anyone involved in commercial aviation operations, whether as an aircraft owner, a charter operator, or a business that charters aircraft for executive travel. Part 91 vs. Part 135: The Regulatory Divide The distinction between Part 91 and Part 135 operations is the foundational regulatory concept in private and commercial aviation. Part 91 governs general aviation operations conducted for personal or business purposes where the flight is not offered for compensation or hire. Part 135 governs on-demand air charter operations and certain commuter air carrier operations where passengers or cargo are transported for compensation. The operational requirements under Part 135 are substantially more rigorous than those under Part 91. Part 135 operators must hold an Air Carrier Certificate issued by the FAA, maintain a comprehensive operations manual, employ a Director of Operations and a Chief Pilot who meet specific qualification requirements, maintain a detailed maintenance program approved by the FAA, and submit to regular surveillance and inspection by FAA inspectors. Crew qualification standards under Part 135 exceed Part 91 requirements in several respects. Pilots must meet higher flight time minimums, complete recurrent training at specified intervals, and comply with more restrictive duty time and rest requirements. These enhanced requirements reflect the higher standard of safety expected for operations conducted for compensation. The consequences of conducting what the FAA considers Part 135 operations without proper certification can be severe. Enforcement actions may include civil penalties, certificate actions, and in egregious cases, criminal prosecution. The FAA's interpretation of what constitutes compensation is broad and can encompass arrangements that parties do not intend as commercial operations, making careful legal analysis essential. Aircraft Management Agreements Aircraft management agreements govern the relationship between aircraft owners who want professional oversight of their aircraft and management companies that provide operational, maintenance, and administrative services. These agreements define the allocation of responsibilities, costs, and liabilities between the owner and the management company. The scope of management services varies significantly across the industry. Comprehensive management agreements may include crew hiring and employment, training and recurrent qualification, flight scheduling and dispatch, maintenance scheduling and oversight, hangar and storage arrangements, insurance procurement, regulatory compliance management, and financial administration including budgeting and expense reporting. Operational control is the most critical concept in aircraft management. Under FAA regulations, the entity that exercises operational control of a flight bears primary responsibility for the safety and legality of that operation. The management agreement should clearly establish which party exercises operational control under various operating scenarios, as this determination affects regulatory obligations, insurance coverage, and liability exposure. When the aircraft is operated under the management company's Part 135 certificate for charter flights, the management company exercises operational control and bears the associated regulatory responsibilities. When the aircraft is operated under Part 91 for the owner's personal or business use, operational control may reside with the owner, the management company, or may be shared depending on the specific arrangements documented in the management agreement. Charter Agreement Structures Charter agreements between operators and customers take several forms depending on the nature of the relationship and the frequency of use. On-demand charter involves individual trip arrangements, with each flight covered by a separate charter agreement. Jet card programs sell blocks of flight time that the customer can use on demand, with the specific terms and conditions docu