To Pan or not to Pan, this is the question. Not wishing to sound like an IFS loser, but anyone that has been to BP for any of the FS courses will know:
To quote JSP 550, the following occurences should be reported: Air Incident, Air Accident, Ground Accident and Ground Incident;
occurrences that represent an actual or potential FS hazard;
errors by aircrew, controllers or logistics personnel that significantly reduce the levels of safety normally expected; abandoned take-offs or unintentionally leaving a runway, taxiway or aircraft operating surface in the event of a serious system or component malfunction; significant loss of thrust/engine power;
significant failure or unforeseen degradation of any safety critical system; flying control system failure or malfunction, or UFCM however momentary; any item that becomes detached from or falls from an aircraft; injury to any personnel incurred during the operation of an aircraft; equipment failure or deficiencies causing significant concern to the user; flight simulator occurrences which may be of benefit to the wider flying community, but excluding those of a Health and Safety at Work nature; etc, etc the list goes on. But I'm spent.
Suffice to say, if you have to declare an emergency it must have been an actual or potential FS hazard and you will have to fill-in one of those complicated and tedious incident signals; you know, the one with the template, where you go to the TV with the keyboard and you fill-in the blanks (don't worry no joined-up writing), press print and hand it to the engineers. Who then pass it up the chain for you, until it reaches command Flight Safety and IFS/WTF. A sad and tiring waste of 4 minutes I know.
Even if you don't declare the magic phrase, as our 4-engined friend decided not to, you still have to fill-in an Incident report! Still, it was an old aeroplane, and there weren't that many on board....
Oh, an IR is required 'when an individual in direct support of aircraft operations has been adversely effected by injury; incapacitated due to illness, the use of drugs or alcohol; or affected by noxious fumes or food poisoning. This includes aircrew or support personnel who, for any reason, are required to report to a medical officer after an incident'. Questions?