Home > Airplane Appraisals > Appraisal Details > Grading Instructions

In order to standardize the grading of aircraft, aircraft appraisers use standards similar to the following when judging aircraft. For continuity, we ask that all aircraft owners use these same standards when describing their aircraft.

Historical data from tens of thousands of appraisals over the past 20 years have shown that, in any category (airframe, paint, and interior), about one-third of all aircraft can be described as rating a "5" ("Average"), with one-third rating between "6" and "10" and the other third rating between "1" and "4".

BE HONEST! Inflating the condition of an aircraft can result in problems with the aircraft qualifying for financing at the resulting inflated purchase price. If the lender requests that an appraisal be conducted, as over 5,000 banks routinely do, and the appraiser's computed value differs significantly from the owner's asking price, the sale will  fail. In addition, if you claim the aircraft is an "8" and a buyer travels thousands of miles to inspect it, only to find that it is really a "6," the sale will fail and buyer will understandably be resentful.

To convert numerical ratings to phonetic ratings, use this table: 

SUPERFICIAL DAMAGE HISTORY: Slight dings generally associated with hangar rash etc. which have been repaired via replacing damaged areas with new or used serviceable components (Hangar rash, wing-tip caps, wheel pants, plastic etc.).
MINOR DAMAGE HISTORY: Ostensibly minor damage or heavy wear to leading edges of wing, wing-tip, cowling etc. which has been repaired in a manner consistent with manufacturers recommended procedures. No structural components were involved.
MODERATE DAMAGE HISTORY: Extensive damage to components not affecting major structural components. (i.e., gear up landing, fuselage or flight surface skins were repaired or replaced, etc.)
MAJOR DAMAGE HISTORY: Major structural component damage but replaced with new or used serviceable components and repaired in accordance with manufacturers recommended procedures, (i.e. tail surfaces or wing replaced, wing spar, fire-wall and engine mounts etc.).
EXTENSIVE MAJOR DAMAGE HISTORY: Major structural components have been extensively damaged but repaired in accordance with manufacturers recommended procedures.

#10 Rating: A person inspecting the airplane closely would have trouble determining the difference between the subject airframe and a brand new one. The airframe has at least 30% fewer hours than the fleet average. Structural exterior surfaces are absolutely flawless. External surfaces (aluminum, epoxy, wood and fabric) are wrinkle, crease and blemish-free, in all light conditions. All rivet, stitch or glue lines are straight and even. Rivets are pulled evenly. There are no abnormalities and the aircraft is in flawless, like-new condition with no damage history. Maintenance has almost always been performed by factory service centers.
#9 Rating: The airframe has at least 30% fewer hours than the fleet average and is less than 20 years old. Exterior surfaces are almost flawless and would meet the #10 criteria except for 1 or 2 minor exceptions. The aircraft has had no skin or structural repairs and no damage history. Maintenance has almost always been performed by major-name shops with excellent national reputations.
#8 Rating: The airframe has at least 20% fewer hours than the fleet average and is less than 25 years old. From 10 feet away, the aircraft would appear to meet the #9 criteria. On closer inspection there may be minor deformations on the underside of aircraft surfaces, minor abrasion on leading edge surfaces, but there are no cracks in the aluminum which have been stop-drilled. Around cowling fasteners, inspection plates and door entry latch etc., there may be evidence of slight wear and/or abnormalities. Aircraft has no history of corrosion and if damage history exists the damage would have been minor in nature (no gear up landings!), new OEM parts were used to repair it, and the repaired damage is 100% undetectable. Maintenance has almost always been performed by shops which have excellent regional reputations.
#7 Rating: The aircraft has average or below-average total time compared to the fleet average and is less than 35 years old. From 10 feet away, the aircraft would appear to meet the #8 criteria. Airframe shows very well with few areas of minor dents or deformations. Airframe is corrosion-free, however it may have had minor surface corrosion which has been cleaned, treated and painted. Cowling fasteners may show wear, along with inspection panels, door and cargo door entry areas. There may be one or two  cracks in the skins which have been stop-drilled. Any damage history, such as a gear-up landing, is now undetectable by inspection, would not have involved major structural components of the airframe (wing spar etc.), and was repaired according to manufacturer's procedures. Any hail damage would have been repaired in a manner which is now undetectable. It has a history of regular maintenance well-documented by the logs.
#6 Rating: The aircraft may have up to 20% higher total time than the fleet average. It would meet the #7 criteria except that it may have had structural damage to major components. However, all repairs were performed to manufacturers specifications, and only an expert looking closely could detect them. Corrosion history is not extensive and affected surfaces have been repaired and treated. Leading edge surfaces might have a few dents, and high use areas such as cowling fasteners, aircraft entry, inspection panels etc. show evidence of moderate wear. Up to five cracks in aluminum have been stop-drilled and repaired, and the repairs appear to have been successful. Hail damage to flat surfaces are not noticeable beyond 5 feet of the aircraft. Any deformations are of a nature which are not a major distraction to the appearance of the aircraft. It has a history of regular maintenance documented by logs.
#5 Rating: The aircraft may have up to 40% higher total time than the fleet average. The airframe is structurally sound and airworthy, and appears to be in good condition, but it is clearly used. Leading edges may show evidence of abrasion wear. Surfaces under the wings, fuselage and gear show some evidence of nicks and abnormalities from prop slung pebbles etc. Minor, untreated surface corrosion may be evident on external surfaces which can easily be repaired by stripping, chemically treating and repainting the affected areas. The flat surfaces may show minor hail damage which would not be noticeable beyond 10 feet away from the aircraft. Aircraft may have sustained extensive damage, but has been repaired in a manner which is consistent with factory recommendations and procedures and would be difficult to detect if you didn't know where to look. There may be a few cracks in the skin which need to be stop-drilled. There may be some minor hangar rash type of discrepancies on the airframe which do not affect the safety or flight performance of the aircraft.
#4 Rating: The airframe may possess the discrepancies described in the #5 Rating but to a larger extent. The overall appearance is obviously below average, even to a layperson. It may have significantly more than 40% higher total time than the fleet average. There may be quite a few cracks which need to be stop drilled. Any hail damage may be quite noticeable. The airframe is safe and meets basic airworthiness standards at this time, but it may not if maintenance is not performed in the near future.
#3 Rating: The airframe is in poor condition and requires maintenance and repair before the aircraft can pass an Annual Inspection. It has deteriorated to a point that continued service would be unwise without immediate maintenance and repair.
#2 Rating: The aircraft requires very extensive repairs to become airworthy and the extent of repairs is such that the cost may exceed the value of the aircraft.
#1 Rating: The aircraft’s only value is salvage.

EXTERIOR GRADING INSTRUCTIONS

#10 Rating: The paint obviously appears new (less than 2 years old) and flawless, even to an expert. It was obviously applied by top craftspeople. All surfaces have a deep, rich, wet look. The paint job quality is as good as factory-new: There is no pooling, sagging, running, orange peeling, thin areas or over-spray on any painted surfaces. Stripes and numerals are well defined with crisp lines and no irregularities. If a re-paint, all surfaces have been stripped and prepared properly and consistent with industry-leading standards and procedures. The windows and any plastic or fiberglass parts are new and flawless.
#9 Rating: The paint looks almost new and flawless from 5 feet away. The paint was applied less than 5 years ago. It would meet the #10 Rating criteria except, upon very close inspection by someone who knows what to look for, it doesn't quite have that "factory new" appearance. For example, there may be dust particles in the paint or a a bit of over-spray, pooling, or sagging, but these items would not be apparent to most pilots or their passengers. The windows look basically new, as do any plastic or fiberglass parts.
#8 Rating: The paint was applied less than 10 years ago in a modern-at-that-time scheme and was done well, with no obvious defects from improper preparation or application. It has a wet look but now there are a few (one or two per square foot) minor chips or scratches under the wings, fuselage and empennage and around fasteners. These can only be detected at less than an arm's length away. A couple hours with touch-up paint would likely restore it to be close to the #9 Rating criteria. Overall, the paint is in very good condition and looks great from 10 feet or more. Almost no pilot would think it needs repainting; most would be proud to own it, and passengers would feel comfortable flying in the aircraft. The windows look new except for one or two small scratches that are difficult to discern except upon close inspection. Fiberglass and plastic parts are in very good condition.
#7 Rating: Paint has a good shine with slight abrasion wear on leading surfaces (no more than three or four chips or scratches per square foot), but it is still retaining good coverage and does not need repainting. Touched up areas are not noticeable. If the paint was applied in the last 10 years, it may have been poorly applied, with orange peel, pooling, sags or over-spray. However, painted surfaces are well protected and the aircraft has good eye appeal from at least 20 feet away. The paint scheme may date the airplane, but only a few of the more discerning pilots would think it needs repainting. The windows are clear with no crazing or discoloring, although there may be a few minor scratches. Fiberglass and plastic parts are in good condition with no cracks or crazing, and with good paint coverage.
#6 Rating: Paint may be showing its age, with some oxidization and obvious abrasion wear on leading edges. It does not technically need repainting, but the styling may be so obviously dated that it makes the aircraft show its age. With touch-up and a good cleaning and waxing, it would have a semi-gloss appearance that would likely move it to the #7 Rating. If the paint is less than 10 years old, it was cheaply done, very poorly applied and has obvious pooling, sagging, running or orange peeling and significant amount of foreign particles in paint. Accent trim may be of poor quality, but paint overall would be adhering well to surfaces. Small crazing or small stress cracks (fewer than two or three hairline cracks per square foot) are visible in plastic and fiberglass parts. Several windows may be milky at the edges only. Overall appearance from at least 20 feet away is fair to good, but many pilots would think it needs repainting.
#5 Rating: The paint scheme obviously dates the aircraft or the paint job to be more than 20 years old. The paint is oxidizing and there may be numerous areas of chipping on lower surfaces of the aircraft and the leading edges of the wings. Two or three small areas (rounded corner of cowling, part of leading edge, etc.) of crazing can be found in the paint. Any previously touched up areas are obvious on close inspection. To bring it up to the #6 Rating criteria, some areas, such as the leading edges and underside of wings and empennage, would need repainting. Surface corrosion may be apparent on the airframe and will affect paint because the painted surface must be stripped in order to treat the corrosion. Overall appearance from at least 20 feet away is just fair. A majority of pilots would say it needs repainting, and some passengers would be nervous about flying in the aircraft, thinking that the poor paint reflects a poor maintenance history. Some windows (less than half) have milky edges and may be crazed or lightly scrated.
#4 Rating: Consistent with all of the characteristics of #5 rating except that the obviously dated styling and numerous areas of obvious wear make the plane look old and un-cared for, and all pilots would agree that it needs to be repainted. Overall appearance is poor to fair; touch-up and cleaning/waxing will not significantly improve the appearance or protection of the aircraft surfaces. Surface corrosion may be evident in more than a few places. Most windows are crazed and scratched. Most passengers would be nervous about flying in the aircraft.
#3 Rating: Paint is poor quality, heavily oxidized and shows excessive wear on leading edges and control surfaces. Many (five or six per square foot) chips and scratches are apparent, but the paint is still protecting the majority of surfaces. However, it looks poor and would make the aircraft difficult to sell unless significantly discounted. All windows are scratched. Passengers would find an excuse not to fly in the aircraft.
#2 Rating: Aircraft needs painting. No good points.
#1 Rating: Aircraft needs painting, and additional preparation of the aircraft surfaces is required before painting. Generally consistent with aircraft having extensive corrosion on surfaces, and, as a result is unairworthy.

INTERIOR GRADING INSTRUCTIONS

#10 Rating: Interior condition is new and flawless and of a modern design. It was installed within the past 2 years. All material, fabric, plastic, carpet, headliner, wood cabinetry, etc. are spotless, with no matting, scratches or signs of wear. Seams are straight, tight and in general the interior looks, feels and smells new and unused.
#9 Rating: Interior is almost flawless and it would meet the #10 rating criteria except for minor exceptions: Carpet at the entry area and in the cockpit, and perhaps the pilots, and/or the copilots seats, may show slight signs of matting. The interior was installed in the past 5 years and is of a mostly modern design.
#8 Rating: Interior may have been installed 5-10 years ago, but is very clean with no tears, loose stitching, stains, fading or excessive wear on fabric, carpets, plastic, wood cabinetry, or headliner. No plastic pieces are cracked. Any smell, dirt or matting can be removed by vacuuming and light shampooing only.
#7 Rating: A small amount of wear is apparent, and the interior is starting to show its age, either because of its condition or its outdated design. Interior may have been redone 10-15 years ago, but it is clean with no tears, major stains or fading, nor excessive wear or scratches on fabric, plastic, wood cabinetry, or headliner. Carpet at entry and cockpit areas may show signs of wear or filth but is is not ragged. Stitching of the fabric is tight, although the seams may not be straight. No plastic pieces are cracked or yellowed and no upholstery repairs have been made in the past nor are needed now. Stain remover and shampoo removes almost all stains. Headliner is clean with no stains. Once cleaned, the interior would be rated a #8.
#6 Rating: Although the interior has a few stains which do not clean up, and the overall appearance is clearly "used," in general the interior is in good serviceable condition. It may have been installed or redone as long as 20 years ago, and the design may appear dated. Any dirty spots in the headliner can be removed almost completely with cleaning. The carpets show significant wear at entry and cockpit areas, with some matting that can't be removed by vacuuming. One or two plastic pieces are cracked and need replacement, and the plastic may be yellowed slightly. There may be matting of materials on seats with wear noticeable on arm rest and lower seat cushions, but this is less noticeable after steam cleaning and scrubbing. No frayed or torn fabric is apparent now, but there may be evidence of minor repairs performed in the past if you look very closely. After a good steam-cleaning and scrubbing, the interior would still look attractive and earn a #7 Rating provided no plastic pieces are cracked. The interior condition would not detract institutional buyers and most private buyers if the aircraft was in otherwise good condition.
#5 Rating: The interior may have been installed or redone more than 20 years ago and, if so, it is obvious that its design was from a different era of style. Entry areas, cockpit and other high use areas show significant signs of wear and/or stains that don't shampoo out. Seat cushions, headliner and side panels may have stains, loose stitching, some fading, and in general a "well used" appearance, but they are not torn. More than two plastic pieces may be cracked and need replacement, and significant yellowing may have evident. Past repairs may be evident. Small nicks are visible in woodwork. About one-third of the seats and drawers do not operate smoothly. After repairs are made and a professional steam cleaning, scrub, and detail job are performed, the condition may warrant a #6 Rating. If the rest of the aircraft is in good condition, the interior's condition would still appeal to most institutional buyers, but discounting would be required in order to sell the aircraft.
#4 Rating: Generally the interior has the same characteristics of a #5 rating except more repairs may be needed and more plastic pieces need replacement. Scratches, stains and frayed fabric areas are seen on most seats. More than half of the leather or vinyl seats may have small cracks. The carpet is matted in many areas and has numerous stains, snags or other irregularities. Any fabric areas exposed to sunlight may be faded and beginning to dry rot. About half of the seats and drawers do not operate smoothly. Wood laminates may be peeling slightly. Interior cannot be made to look clean or small fresh, but once repairs are made and the interior is cleaned, it would be at least serviceable for some time. Most private and institutional buyers would shy away from an aircraft with this interior unless they were well compensated for doing so. Passengers would be hesitant to fly in the aircraft because they would be nervous that the poor interior reflects a poor maintenance history.
#3 Rating: The interior has all the conditions of a #4 rating except numerous repairs may be needed; tears, snags, burns, and stains may be clearly visible in many areas. Most seats and drawers do not operate smoothly, if at all. The interior smells and looks dirty even after deep cleaning. The interior is no longer serviceable, and would preclude the aircraft from being sold unless the buyer received enough of a discount to cover the cost of a new interior.
#2 Rating: Seats have exposed foam. The carpet is thread-bare. The extent of needed repairs would not be cost-effective. The interior needs to be replaced and the aircraft will likely not sell until it is.
#1 Rating: The interior is in such poor condition that most poeople would be hesitant to sit down for fear of damaging clothing. Generally all of the characteristics of #2 are evident, but the required repairs must include interior structures such as seat frames, chair rails, cabinetry etc.