"Incident" or "Accident"?

[ChristiaanJ]

I just received an NTSB e-mail, titled:
"NTSB TO RELEASE FACTUAL REPORTS ON TWO AVIATION ACCIDENTS"

The first one concerns a runway overrun of an RJ CL600.
"There were no injuries among the three crewmembers and 49 passengers (including 3 lap-held children). The airplane was substantially damaged."

The second one is about a Beechcraft 400A which lost power on both engines.
"After landing, the aircraft rolled off of the runway onto a taxiway, and the right landing gear tire deflated. [...] The two pilots on board were not injured."

Now, I have always been under the impression that in aviation an "accident" implied at least one fatality, and that everything else was formally an "incident".
While I'm ready to admit that this is probably too restrictive a definition, I would still have called the first event an "incident", in view of the fact that there were no injuries.

As to calling the second event an "accident", that seems faintly ludicrous.

Any comments?

The question is not just a matter of language use: statistics tend to distinguish between "accidents" and "incidents".

[FIRESYSOK]

http://frwebgate.access.gpo.gov/cgi-bin/get-cfr.cgi?TITLE=49&PART=830&SECTION=2&TYPE=TEXT

[Blinkz]

Well there are set definitions about exactly what an accident and an incident are. As I understand it an accident is when any person is killed or seriously injured or an aircraft receives serious damange. An incident is someothing other then an accident that involved, or could have led to being involved in an accident......:ugh:

[ChristiaanJ]

Many thanks to all!

To save anybody else looking it up, the NTSB document says:

"Aircraft accident means an occurrence associated with the operation
of an aircraft which takes place between the time any person boards the
aircraft with the intention of flight and all such persons have
disembarked, and in which any person suffers death or serious injury, or
in which the aircraft receives substantial damage."

"Incident means an occurrence other than an accident, associated with
the operation of an aircraft, which affects or could affect the safety
of operations."

(The document then defines fatal and serious injury, and substantial damage, in more detail.)

Those definitions also fit in far better with common usage than my too restrictive definiton.

So the first event quoted in the thread start qualifies as an accident (substantial damage), the second one does not, even if it definitely qualifies as an incident (loss on power on both engines....).

[Rainboe]

I've always understood an 'accident' implies an inadvertent contact such that damage or injury was caused. An 'incident' implies to me that damage or injury was not, or probably not caused. There will be blurring of this. Hence:
Any collision involving any vehicles, with or without injury, with each other or any other object- accident
Any near collision, with or without injury- incident.
So an evasive near miss involving passengers being thrown about and hurt- incident. The moment that involved inadvertent contact between the vehicles or with any object- accident (whether injury occurs or not)

[ChristiaanJ]

Rainboe,
I was more looking for the formal definition as used in an aviation context.

With your definition, unless seriously qualified, the A380 having a winglet "dinged" at Bangkok would be classed as an accident ("inadvertent contact with an object").

[Blinkz]

The AAIB have a special department which only deal with deciding if something is an accident or incident :}

[Rainboe]

Christian- I said that blurring will definitely make any rigorous definition impossible. The superficial A380 damage is probably accident because of the nature and importance of the event. However in my training days, I indvertently took off with 6 inches (OK- 15 cms for you!) of seat belt with a large metal buckle on the end hanging outside the door opposite on a Cherokee. At lift off it started flailing damaging the fuselage (nothing like the damage the sound did to my nerves- I thought the wing was falling off). Certainly not an accident- only an incident. There will always be this area where they blur together. But I think a large part of the definition is 'how important was the incident?'. But then, 200 injuries as a 747 takes avoiding action in the air- still only an 'incident'? Any sort of contact- accident.

Not an easy question!

[Mad (Flt) Scientist]

ICAO Annex 13 provides the "real" international definition:
full text (http://www.airsafety.com.au/trinvbil/C619icao.pdf)

to save bandwidth ...

Accident. An occurrence associated with the operation of an aircraft which takes place between the time any person boards the aircraft with the intention of flight until such time as all such persons have disembarked, in which:
a) a person is fatally or seriously injured as a result of:
— being in the aircraft, or
— direct contact with any part of the aircraft, including parts which have become detached from the aircraft, or
— direct exposure to jet blast, except when the injuries are from natural causes, selfinflicted or inflicted by other persons, or when the injuries are to stowaways hiding outside the areas normally available to the passengers and crew; or

b) the aircraft sustains damage or structural failure which:
— adversely affects the structural strength, performance or flight characteristics of the aircraft, and
— would normally require major repair or replacement of the affected component, except for engine failure or damage, when the damage is limited to the engine, its cowlings or accessories; or for damage limited to propellers, wing tips, antennas, tires, brakes, fairings, small dents or puncture holes in the aircraft skin; or

c) the aircraft is missing or is completely inaccessible.

Note 1.— For statistical uniformity only, an injury resulting in death within thirty days of the date of the accident is classified as a fatal injury by ICAO.
Note 2.— An aircraft is considered to be missing when the official search has been terminated and the wreckage has not been located.

and

Incident. An occurrence, other than an accident, associated with the operation of an aircraft which affects or could affect the safety of operation.

Note.— The types of incidents which are of main interest to the International Civil Aviation Organization for accident prevention studies are listed in the Accident/Incident Reporting Manual (Doc 9156).

So, the A380 winglet certainly isn't an "accident", since damage to wing tips is excluded, AND it probably wouldn't be considered to meet the first clause for structural damage either (so it fails the accident check on two different counts)

Rainboe's 200 injured pax would almost certainly have at least one "serious" injury, but, if not, "incident" is correct. (serious is defined also, I believe)

[ChristiaanJ]

Rainboe,
Check FireSySok's link:
http://frwebgate.access.gpo.gov/cgi-bin/get-cfr.cgi?TITLE=49&PART=830&SECTION=2&TYPE=TEXT
and you'll see they make a fair effort to minimise "blurring".

Your 747 event with 200 injuries would almost certainly have involved several "serious" injuries as defined by the NTSB, which would have made it an accident.

[ChristiaanJ]

Mad (Flt) Scientist,
Thanks!
The NTSB document FireSySok linked to looks very much like a slightly simplified but otherwise unaltered version of the ICAO Annex 13 document.

Rainboe,
You may notice both documents exclude wingtips (and one may assume winglets) from the "substantial damage" definition.

[xetroV]

The first one concerns a runway overrun of an RJ CL600.
"There were no injuries among the three crewmembers and 49 passengers (including 3 lap-held children). The airplane was substantially damaged."
"Substantial damage" probably makes this an accident (although one can't be sure without knowing the exact nature of the damage; e.g. a contained engine failure would be considered an incident, even if the engine itself was substantially damaged).

The second one is about a Beechcraft 400A which lost power on both engines.
"After landing, the aircraft rolled off of the runway onto a taxiway, and the right landing gear tire deflated. [...] The two pilots on board were not injured."
I too would rate this an incident, based on the given information (probably a "serious incident", i.e "an incident involving circumstances indicating that an accident nearly occurred" - Annex 13). However, if the deflated tire would have caused secondary damage to e.g. the landing gear, wing, or airframe structure, it could be an "accident", depending on the nature of the damage.

[GlueBall]

It's dubious that the A380 "dinged" winglet by a hangar door during tow by ground crew would qualify even as an "incident" because the airplane was not "operated," nor is the winglet a structural component; most likely in fact is that the A380 could be dispatched without a winglet, just as a B744 could.