Aircraft Depreciation Calculator

Why does this use a floor instead of pure exponential decay?

Airframes don't depreciate toward zero the way cars or electronics do because the underlying structure, with proper maintenance, has an indefinite service life and value tends to stabilize once an aircraft is old enough that buyers are paying mainly for engine/prop time remaining and avionics condition rather than airframe age itself. A floor around 30-50% of original value better reflects how older, well-maintained trainers and simple singles actually trade.

Why do some aircraft appear to gain value?

Rising demand for trainer-category aircraft, general inflation in aircraft prices (notably after 2020), and low new-aircraft production have pushed used prices of common trainers like 172s and Cherokees up in nominal dollars even as they age, which can look like value appreciation despite the underlying airframe aging normally. This calculator models a depreciating baseline and doesn't capture market-wide price inflation.

Does an engine overhaul restore lost value?

Yes, substantially — a fresh overhaul typically adds most of its direct cost back to resale value since buyers pay a premium for low time since major overhaul (SMOH), effectively resetting part of the depreciation clock for the engine even though the airframe continues aging normally.

How does avionics affect this estimate?

An aircraft with an outdated panel lacking ADS-B Out or modern glass avionics can see accelerated effective depreciation as buyers increasingly discount or avoid older panels, while a recent glass panel or ADS-B-compliant upgrade adds value roughly in line with upgrade cost for several years before that upgrade itself starts to age out.