Accident vs. Incident

Oct. 13, 2016
Title 49 of the Code of Federal Regulations Part 830, §830.2 helps one understand the differences between an accident and an incident.

My grandson, Ethan, came in the house wearing a wry smile and spoke in some cutesy, grammar-starved fashion, “I hads a accident with your car.” Translation: he ran his Big Wheel into my commuter-mobile’s rear tire. I was Ear-i-tated! No, no, I was pretty damn mad! “Did you sustain any substantial damage?” I asked. His eyebrows rose as the smile vanished. “You look OK; any serious injury?” His eyes widened and the jaw dropped. I was going for the jugular when his over-protective mouthpiece, that pre-school enabling enemy of common sense – Grandma, stepped in front and diffused the event.

Kids, they think they know everything!

Ethan should have read Title 49 of the Code of Federal Regulations Part 830, §830.2; it helps one understand exactly what an accident is. I keep a copy next to The Cat In The Hat and the other bedtime stories – sleep-inducing gold. These regs specifically state the differences between an accident and an incident. For those with an FAA mentality, the Flight Standards Information Management System (FSIMS) 8900.1 Volume 7, Chapter 1, Section 1, 7–4 General (A) Definitions lays the topic out in layman’s terms. Either way, keep one handy for just such an emergency.


"An aircraft accident is an occurrence associated with the operation of an aircraft that:

• Occurs between when the first person boards the aircraft – with intention of flight – and the last person disembarks;

• Results in death or serious injury;

• Causes substantial damage to the aircraft."

Intention of flight means just that: somebody’s punching holes in the sky. If mechanic Karen is performing a phase check task card and she falls out the entry door – incurring a serious injury – it’s not an aircraft accident. But if flight attendant (FA) Todd, while prepping the cabin, accidentally blows the slide and himself with it, out the same entry door – incurring a serious injury – that’s an accident. Why? Because FA Todd was the first person to board with intention to fly.

Death is self-explanatory. So what is serious injury? It is explained as "an injury that: requires hospitalization for more than 48 hours, within seven days of event; results in bone fracture(s) – except nose, fingers, or toes; causes severe hemorrhages, nerve, muscle, or tendon damage; second or third degree burns over more than 5 percent of the body; and/or internal organ damage." If FA Patty, while conducting beverage service, is seriously injured during turbulence, the event is an accident.

Now let’s say mechanic Mike is taxiing the aircraft to the gate for a pending flight and shears the outboard elevator off – incurring substantial damage – it’s not an accident; no intention to fly. But if pilot Carol buries a slat into an entry stand while taxiing into the same gate – incurring substantial damage – she’s had an accident, because the last person hasn’t disembarked from the flight.

Substantial damage is: "damage or failure that adversely affects the structural strength, performance, or flight characteristics of the aircraft and would normally require a major repair or replacement of the affected component." So pilot Carol’s slat, engine ingested foreign object damage (FOD), and punching a hole in the pressure vessel – on an aircraft with intent to fly – each qualify for substantial damage.

Exceptions to the substantial damage rule are: "engine failure or damage limited to an engine; bent fairings or cowling; dented skin or small punctures in skin or fabric; ground damage to rotor or propeller blades; and/or damage to landing gear, wheels, brakes, flaps engine accessories, or wingtips."


But what about an incident? Plainly stated, "an aircraft incident is an occurrence – other than an accident (no intention of flight) – associated with the operation of an aircraft that affects or could affect the safety of operations."

Let’s put these conditions into practical examination. United Airlines Flight 232, a DC10 that crashed in Sioux City, IA, on July 19, 1989, suffered an uncontained No.  2 engine failure. Did it start out as an accident or incident? The first half-second of the event began as an incident because of the substantial damage exception: engine failure or damage limited to an engine – if it remained an engine failure. However, the next half-second determined the event, an accident. Once the compressor blades penetrated the engine casing and sliced open the three hydraulic systems’ hydraulic lines, it was, from that moment on, an accident.

That fact may seem trivial; after all, 111 people were killed … in that very real accident. But my point is to examine what constitutes an accident or an incident. And with that clarification, what needs to rise to the level of NTSB or FAA investigation and which can be limited to an air operator’s in-house investigation.

My playfully introducing my grandson into the article demonstrates the general news media’s childish ignorance of our industry and what they write about. A captain dies of a heart attack, and the First Officer ‘miraculously’ lands the plane at the next airport. An engine fails in flight and the entire cabin finds religion for a ‘harrowing’ 15 minutes. An airliner blows a main tire on rotation and the passengers scream for a Congressional hearing into tire ply safety.

Naturally the first officer lands the plane; he/she has been trained; the event is called an accident only because someone died during the flight. A tire failure or a contained engine failure – both considered incidents – are unfortunate, but they happen. There’s no call for panic.

The news media should focus on real threats to safety, e.g. amateur unmanned aerial vehicle (UAV) operators. Frequent airline reports of near misses with UAVs on approach is call for panic – major panic, for there’s no control. These amateurs’ irresponsible behavior around helicopters, airliners, and GA makes Ethan look like an adult by comparison.

The main difference between accidents and incidents is intent to fly. We, in aviation, always have the intent to be safe; yet we still – occasionally – have accidents and incidents. What if one’s whole intent is to play chicken with aircraft? We most likely get substantial damage, serious injury … and death.