Aircraft valuation testimony can be decisive in a dispute, and it can also be the weakest part of a case. Incomplete maintenance logs, undocumented upgrades, and market volatility already make aircraft hard to value. Errors in the analysis make it harder.
Over more than 30 years of appraisal and expert witness work, we’ve seen the same mistakes repeated. Here are seven of the most common, and how attorneys can spot them.
Price guides give average values for typical aircraft. They don’t account for the specific aircraft’s times, engine status, records, equipment, or damage history, and they don’t always reflect what aircraft actually sold for.
How to spot it: The report cites a guide value with few or no comparable sales, or makes adjustments without supporting data.
A valuation is only as reliable as the records behind it. Common problems include missing logbooks, gaps in the history, engine times that weren’t verified, and repairs that weren’t disclosed or documented.
How to spot it: The report doesn’t list which records were reviewed, or takes times and history from a listing or summary instead of the logbooks.
Because engines carry so much of an aircraft’s value, engine errors can distort the whole valuation. Common errors include incorrect engine times, ignoring an upcoming hot section inspection, overhaul, or Airworthiness Directive (AD), overlooking enrollment in an engine program, and misvaluing an engine after an incident such as a sudden stoppage or foreign object damage.
How to spot it: The report gives engine times without a source, or doesn’t address the time remaining until the next major event.
Cosmetic damage and structural damage have very different effects on value. So do repairs made to manufacturer standards and repairs that weren’t. Some testimony overstates the long-term effect of minor damage; other testimony understates the effect of major damage.
How to spot it: The report doesn’t describe the type and extent of the damage, how it was repaired, or how the market views aircraft with similar histories.
An opinion of value offered without a clear methodology is hard to test and easy to challenge. Common problems include no definition of value, no explanation of the approaches used, adjustments without support, and no reconciliation of the results.
How to spot it: The opinion is a single number with little explanation, or the report doesn’t state that it follows USPAP.
Many legal matters require value on a specific past date: the date of loss, breach, or transfer. Using current values instead, or applying general market trends without supporting data, is one of the most common errors in valuation testimony.
How to spot it: The effective date of value doesn’t match the legal question, or the comparable sales come from a different period.
Operational history affects value. Errors include not distinguishing Part 91 from Part 135 operation, ignoring high- or low-cycle use, overlooking environmental exposure such as salt air, and not considering the quality of storage and maintenance.
How to spot it: The report treats the aircraft as typical for its model and year without discussing how it was used or maintained.
Each of these errors can be explored on cross-examination, and each can affect how much weight a court gives the testimony. Valuation testimony is most useful when it is independent, based on verified records, supported by actual market data, and developed for the correct date under recognized standards.
Credible testimony comes from a qualified, independent appraiser, relies on verified records and actual sales, uses the correct date of value, and follows USPAP. It also explains each adjustment clearly.
Yes. An independent review can identify errors such as unverified engine times, the wrong valuation date, or unsupported adjustments, and an expert can explain those issues in a report or testimony.
Yes. David Fisher has more than 30 years of experience as an aircraft appraiser and expert witness, and he has never been disqualified as an expert. His CV and testimony list are available on request.
Airframe time, engines, maintenance, avionics, records, and damage history all drive aircraft value. What attorneys should know before a dispute.
Read More → Aircraft Valuation Factors Every Attorney Should KnowRecords gaps, engine status, damage history, compliance, and date-of-value issues often decide aircraft litigation. Six issues attorneys should know.
Read More → Key Aircraft Valuation Issues in LitigationQualifications, definition of value, records, methods, and market data: seven checks attorneys can use to judge whether an aircraft appraisal is reliable.
Read More → How Attorneys Should Evaluate an Aircraft Appraisal
