Nearly every aviation matter eventually turns on the same question: what should this pilot, or this operator, have done? The legal standard that applies to that question, and how a court defines the duty owed, are matters for counsel. My work sits underneath that question. As a corporate Chief Pilot and aviation expert witness, I describe what established aviation practice looked like for the operation in question, and then compare the operational record against it. The two are related, but they are not the same thing, and keeping them separate is what makes the analysis useful to everyone at the table.
This article explains how I approach that operational benchmark. It does not address how any particular jurisdiction defines negligence, and it does not predict how a finder of fact will weigh the evidence.
The Regulations Are the Floor
The Federal Aviation Regulations are the natural starting point, and they are frequently misread as the whole answer. They are minimums. 14 CFR 91.3 makes the pilot in command directly responsible for, and the final authority as to, the operation of the aircraft. 14 CFR 91.103 requires the pilot to become familiar with all available information concerning the flight, including weather reports and forecasts, fuel requirements, alternatives available if the flight cannot be completed as planned, and runway lengths and takeoff and landing distance data. 14 CFR 91.13 prohibits operating an aircraft in a careless or reckless manner so as to endanger the life or property of another. Pilot currency and proficiency rules in 14 CFR 61.56, 61.57, and 61.58 set the baseline for who may act as pilot in command at all.
A flight can comply with every applicable regulation and still fall well short of established practice. Consider a turbine aircraft departing for a destination with deteriorating weather. The pilot can meet the IFR fuel requirements of 14 CFR 91.167 and the alternate requirements of 14 CFR 91.169 to the minute and still have planned the flight with no realistic margin for holding, a missed approach, or a diversion to an airport with suitable runway length. The regulation tells us whether the minimum was met. It does not tell us whether a comparable professional crew would have planned the flight that way. For a closer look at how training and checking records fit into this comparison, see Pilot Training and the Standard of Care.
Where Established Practice Comes From
If the regulations are the floor, the operational benchmark is built from the material that professional operators actually use. Manufacturer guidance comes first: the Aircraft Flight Manual limitations and procedures, normal and emergency checklists, and performance data. These are not suggestions. A crew that operates outside the published limitations, or that skips a checklist flow the manufacturer considers essential, has departed from the most specific standard available for that aircraft.
FAA guidance fills in a great deal of the rest. AC 120-71B describes how standard operating procedures and callouts should be designed and used, including stabilized approach criteria. AC 120-51E addresses crew resource management. AC 60-22, issued in 1991, gives pilots and instructors introductory material on aeronautical decision-making, including risk assessment, stress management, and hazardous attitudes. Advisory circulars are generally not regulatory in themselves, and they vary in purpose. AC 120-71B and AC 120-51E describe what the FAA considers an acceptable way of doing things, and professional operators build their programs around them, while AC 60-22 serves as introductory guidance. The CRM side of this is addressed in more depth on the Crew Resource Management page.
Operator documents are often the most revealing. A corporate flight department's operations manual, SOPs, risk assessment tools, and training syllabi represent the standard that the organization set for itself. When a crew departs from its own company procedures, the comparison is direct. When those procedures are thin or outdated relative to the aircraft and mission, that becomes a separate and equally important finding. Finally, industry standards such as the International Standard for Business Aircraft Operations (IS-BAO) and the safety management system framework in 14 CFR Part 5 describe what well-run operators do above the minimums. Part 5 is mandatory for some certificate holders and voluntary for most Part 91 operators, so its relevance depends on the operation. The differences between those frameworks are covered on the Part 91 and Part 135 Operations page.
Matching the Benchmark to the Operation
The standard is not generic. A private owner flying a single-engine piston aircraft on a personal trip, a two-pilot corporate crew in a super-midsize jet, and a Part 135 charter operator are all held to different operational expectations, because the aircraft, the training, the procedures, and the organizational oversight are different. The first step in any review is identifying the comparable operation honestly. That means the same category of aircraft, a similar mission profile, a crew with similar qualifications, and the regulatory part under which the flight was actually conducted. Characterizing the operation before the records establish it is one of the easiest ways to start an analysis on the wrong foundation.
Conditions matter as well. The standard is evaluated against what the crew knew, or reasonably should have known, at each decision point, not against what investigators learned afterward. A go or no-go decision made with the weather products available at departure is judged by those products. An approach continued below minimums is judged by the visual references and aircraft state at the moment the decision was made. Hindsight is the analyst's most persistent temptation, and the method has to guard against it.
How the Comparison Works in Practice
The review moves chronologically. It begins with preflight planning and the information the crew had, then follows the flight through each significant decision: departure, en route changes, the arrival briefing, the approach, and the final sequence. At each point, I identify what established practice called for, what the record shows the crew actually did, and whether there was a departure between the two. The record usually includes the NTSB docket, recorder data where it exists, ATC communications, weather archives, maintenance and training records, and the operator's own manuals.
The NTSB plays a central role, and its mission is specific. The Board determines probable cause to prevent future accidents, not to assign fault. By statute, 49 U.S.C. 1154(b), the Board's accident report cannot be used in a civil action for damages, while factual reports prepared by investigators are treated differently under 49 CFR Part 835. How that material is used is a question for counsel. Operationally, the docket is the foundation, and an independent analysis explains what the underlying evidence means for pilot conduct and organizational practice.
Individual decisions are rarely unsafe in isolation. A late departure, a fuel stop skipped to save time, and an approach briefing shortened by workload can each look reasonable on their own. Their cumulative effect is what often matters, and the analysis has to show how each one narrowed the margins available for the next. The same approach applies to approach and landing accidents, where the final minutes are usually shaped by decisions made much earlier.
What a Sound Opinion Looks Like
A defensible operational opinion separates documented facts from assumptions, identifies the specific source of each standard it applies, and acknowledges where the record is incomplete. It does not stretch an advisory circular into a regulation, and it does not treat an operator's internal procedure as an industry norm unless the evidence supports that. Another qualified aviation professional should be able to follow the reasoning step by step and test it. That transparency serves plaintiff and defense counsel equally, because the goal is an accurate account of what happened and how it compares to established aviation practice.
Discuss a Standard of Care Question
If you are evaluating a matter that turns on pilot conduct, operator procedures, or flight department oversight, I am available for an initial conversation and conflict check. Learn more about how I support counsel on the Expert Witness Services page.