the difference between an appraisal performed by a member of
the National Aircraft Appraisers Association and an
appraisal performed using one of the aircraft price guides?
The differences are enormous and to answer this question
would take many pages. Briefly let us look at some key
differences. Aircraft price guides are published, marketed,
and distributed by book publishing companies. The facts are,
they do not appraise aircraft, they do not even gather or
generate their own data. Rather, they simply send out a
questionnaire every 3 months to subscribers of their books
and ask a few questions which at best are very vague. From
these questionnaires the book publishers generate their data
An interesting point to consider is this. Nowhere on these
questionnaires do the price guide book publishers request
The aircraft's damage
Engine or airframe
modifications, if any.
Make and model of installed
avionics and if there were any Avionic upgrades.
Physical condition of the
airframe including surface corrosion etc.
Inspection status of the
aircraft. For example, the aircraft may have been out of
Annual for some period of time or/and there may be
Airworthiness Directives and/or mandatory Service
Bulletins which have not been complied with.
Props and time since
Engine overhaul status. For
example, was the engine field overhauled to FAA overhaul
service limits or overhauled to factory new limits or a
Condition of de-ice
equipment, instrumentation and other systems and
It is truly a mystery how one
could generate an accurate database of aircraft values
without a clue regarding the condition of the airframe, make
and model of avionics, damage history, airframe or engine
modifications and all of the other important value points
listed above. The National Aircraft Appraisers Association
is the only organization in the world which considers all of
these factors in its database. Additionally, all of the
information the National Aircraft Appraisers Association
uses is verified by its members who have physically
evaluated the aircraft and each Association member
subscribes to the same evaluation criteria while performing
the appraisal. The end result is an extremely accurate
database that is verifiable.