The following statements apply to all accidents involving all airlines flying all types of aircraft, whether people in them were hurt or not:
1. If the accident involves a big Western-built jet airliner with lots of people on it, it will either be an Airbus or a Boeing, because they are the only Western aircraft manufacturers left on the planet that make big jet aeroplanes.
2. Accidents do not happen because the aeroplane is an Airbus or a Boeing (or an Embraer or a Tupolev), they happen because of a combination of circumstances that often involves natural phenomena like bad weather or darkness (or both), sometimes involves a technical problem, and almost always involves human mistakes or frailties (plural).
3. The humans who made the mistakes will either have made errors of commission or omission (or both), and the errors can become contributory factors or directly causal - usually the former. The list of people (not exhaustive) who might have made a contributory mistake includes: aircraft and aero-engine manufacturers: airframe, engine and avionics maintenance engineers; airline operations personnel; airport handling agents; cargo or baggage managers; air traffic controllers; or pilots.
4. The part played by the corporate or departmental managers whose employees made the front-line errors or omissions might prove to be critical in an accident if the mistakes were the result of inadequate employee selection, training, supervision, or management communication (two-way).
5. Pilots are "the system's goalkeepers". Their main job may be to aviate, navigate and communicate, but they also have to deal with the results of any failure at any point in the organisation upstream of them (see item 3). If the system bangs enough fast balls at them, they will eventually let a goal through, and the media will call it pilot error.
6. Prof James Reason (who invented the "Swiss cheese" model of organisational safety management) was right. Humans will inevitably make some mistakes, so to imagine you can prevent them completely is delusional. The optimum answer is to build a system that is error-tolerant, with multiple layers of defences that will identify and correct a mistake before it combines with other circumstances to become dangerous. That applies to both companies and to aircraft design. Pilots are the last line of defence against errors in either.
7. It is not at all rare for the cause of an airline accident to remain a mystery for a long time, especially if human factors are involved, which they usually are.
8. Accident investigators tend to establish lots of individual facts very quickly because it is easy to see what the result was, but the cause is usually not evident.
9. The flight data recorder and cockpit voice recorder ("black boxes") are both very important to gaining a full understanding of precisely what happened and why it did. But if most of the wreckage, including critical parts like the flight deck, the engines and the control surfaces, is recovered, a great deal can be deduced without them.