My own definition of "damage" is as follows: an event that lead to an unscheduled repair to the aircraft (or engines) that materially effects the resale value of the aircraft. After all, that's really what we all care about isn't it? So for example; someone carries a golf bag into the back of plane and puts deep scratches into the refreshment center which leads to a repair. Is it damage? Yep. Does it effect the resale value; not by much if at all.
Here are some much more obvious forms of damage history starting from the most obvious and going to the least.
1) NTSB Accident or Incident Report- It's doubtful that you'd be looking to purchase a plane that has an accident report filed on it but it's very possible that an incident report was. (The difference between those two is very clearly defined by the NTSB.) It's pretty easy to find out too... just Google the tail number and you'll likely find it. If you REALLY want to dig, here is the link: http://www.ntsb.gov/aviationquery/index.aspx So, does this effect the resale value? YES!
2) FAA Form 337 (Major Repair or Alteration)- Typically this is where you most readily find out if an aircraft has been damaged. The nice part is that 337's go into both the logbooks and get filed with the FAA so if you're considering buying a plane with missing logbooks, you can still get an Escrow Agent to do the search with FAA. Keep in mind though that 337's are referred to as "field approvals" and they are used to accomplished lots of modification as well. Actually, anything that is a "Major Alteration or Repair" that is NOT done by a Factory Service Center. So, does it effect the resale value? Yes, very much if it's not for modification.
3) A repair performed by a Factory Service Center for "damage"- This one is harder to find in a log review and it's even a little sneaky. The FAA allows for the factory to do the same work that a non-factory repair facility does that would require a Form 337 be filed, only, without the 337. The theory is that there is nobody better to fix damage than the people that built it. That's likely a true statement and doing so often times lowers the reduction in sales price that is required from the damage event. Case in point: There was a CJ (525) that happened to fly on the downwind side of a hailstorm and did relatively major damage to all the leading edges of the aircraft including the engine inlets. The plane was flown to a Service Center, leading edges removed, repaired and re-installed. Had they done a complete replacement of the leading edges, it probably would have been completely overlooked as damage because of the parts-off, parts-on nature... but since they were repaired, technically speaking it was damage. Does it effect the resale value? Yep, but to a much lesser extent than if the Service Center hadn't done it. Important note: the buyer for the plane backed out of the deal once we disclosed the repairs... the feeling being, why buy this one when I can buy a near identical one without the damage for the same money.
4) Hard Landing Inspection- This one I hate. This is an event that I feel makes the statement "no damage history" tough to get away with saying. Ultimately it depends on the extent of the hard landing (determinable by how much was repaired as a result) but there is an important point that needs to be considered. Would you rather see a hard landing inspection write up or would you rather NOT see a hard landing inspection write up? In other words, what if rather than bring the plane in for the inspection, the owner decided that it would effect the value of his plane too much and not do the inspection. That's bad too right? Is it damage? Not really. Does it effect the resale value? A little.
5) Lightning Strike Inspection- This is a lot like a hard landing inspection. Planes get struck by lightning all the time but unless its a real obvious hit where systems fail, power goes out and radios stop working, it's probably not damage. Here again, you look at the write up and see what the extent of the repair was. If the nose cone had to be replaced and avionics removed and repaired... it's damage. If the inspection were performed but no repairs needed... it's not.
6) Engine FOD (Foreign Object Debris) Damage- Less common on fuselage mounted engines, more common on wing mounted engines and really, really common on nose mounted engines. At least in my experience. This is mostly about the intensity of the repair though. Was a single blade bent or did it lead to a major overhaul? Was anything else damaged on the way in, like the inlet? It also matters who did the work which I'll address next. Keep in mind that on a lot of the older turbine aircraft, the only value to them is in the engines. If the engines aren't worth much, neither is the aircraft.
7) Corrosion- This is a very, very hard subject to cover. If an aircraft is free from corrosion, it must be made of plastic. Every aircraft has corrosion, regardless of age and every aircraft will have corrosion repairs to it. When it's regarding pressure vessels and wing spars... run. If its found in an engine borescope... check with the manufacturer on the tolerances... consider running. If it's in gear wells, that happens...
A couple of important things to point out: If you're basing your determination on how much an event (damage or not) changes the value of an aircraft solely on the logbook entry you need to consider first and foremost, who did the inspection. If it was the manufacturer, that's very good. If it was not the manufacturer but someone highly reputable with good brand recognition, that's good too. If it was someone that nobody has ever heard of and probably hires contract employees, that's not good.
Its very possible for an aircraft to sustain some pretty major damage and, if repaired properly, minimally effect the resale value. If it's related to the aircraft structure, it better have been done by the manufacturer and you really need to ask yourself whether or not this is the right plane. Others see damage as an opportunity to get a really great deal on a plane that is almost as good as new and in some cases better!
Its very possible for an aircraft to sustain some pretty major damage and, if repaired properly, minimally effect the resale value. If it's related to the aircraft structure, it better have been done by the manufacturer and you really need to ask yourself whether or not this is the right plane. Others see damage as an opportunity to get a really great deal on a plane that is almost as good as new and in some cases better!
My recommendation is simple: before you buy an aircraft, make sure you hire a competent, experienced, and reputable maintenance facility or technician to perform a thorough logbook review. Aircraft brokers (myself included) are NOT qualified to perform these reviews. Pilots are NOT qualified to perform these reviews either. Only actively licensed IA's and A&P's that work for active Part 145 repair facilities with experience in that make and model are qualified. Here is a link to the FAA's Repair Facility search database: http://av-info.faa.gov/repairstation.asp USE IT!
And here's the disclaimer: The information contained within this blog is only intended to be used for informational purposes only and NOT for actually determining the complex definition of damage.