The commercial aviation world obsess about statistics, and some countries (eg USA Part 121 operations) enjoy accident rates well below one in a million hours.
The Flight Safety institute drills down into phases of flight statistics and sponsors initiatives such as ALAR.
http://flightsafety.org/current-safety-initiatives/approach-and-landing-accident-reduction-alar
Private GA seems to spend less time on the topic, and appears to accept roughly 1 in 30,000-60,000 hours fatality rate as the acceptable rate before society/politics acted, presumably in a regulatory fashion – I say this because the rate has stayed stubbornly at this level for some decades.
As pilots, when flying privately, what is our aim for an acceptable average accident loss expectation (fatality/morbidity)? 1 in 100,000 hours (we would be above average, superior pilots at this rate)? 1 in 200,000 hours?
Do we calibrate risk appetite for different types of aircraft, and type of operation? Should we require private pilots to learn the statistics of different types of operation? The safety gains of operating to Class B commercial standards for planning and performance? The reduction in safety margin depending on weather, night/day, mountainous terrain, IFR/VFR, etc?
My working assumption is that a current PPL with an IR, operating from ATC airports with an ILS in a relatively un-complicated, certified and well maintained single engine aircraft, on airways, in daylight, and in VMC or light IMC (no icing, convective, and ceilings visibility allowing some chance of picking a field – say 1,000’ AGL and 2 miles) – should be able to have an expectation of 1 in 200,000 hours or better. As the private operation departs from this scenario the risk parameters would shift, arriving eventually at some types of flight operation where if they were discussed with family or passengers would be deemed to be unacceptable.
Conceivably there could be a simple app which would spit out the increase in fatality/morbidity risk depending on the type of operation, over the base risk?
RobertL18C: you have been flying through Africa (inspiring me to do the same last year), so you know the risks can be higher flying over the Sahara dessert e.g. or overhead thick jungle/forests in Central Africa.
Personally I think that the risk we are willing to accept has to do with our personality. There are a lot of different personality tests but one comes to mind from an American lady Dani Johnson. She talsk about a Pearl, Sapphire, Ruby and Amerald. See: http://www.awaionline.com/2011/11/are-you-a-ruby-sapphire-pearl-or-emerald/
Rubies like to win. They are motivated by challenges. They like to have the best of everything. Rubies constantly have to be striving for a goal, a next step, or another challenge. Rubies are often business owners and entrepreneurs because they like to lead. They are also blessed with extra confidence and they’re not afraid to take a risk.
Where Rubies take on more risk, others like Pearls don’t take any risk at all.
It is hard to bring in more safety features in aircraft as the personality of the pilot does not change. What might help is for the pilot to be aware where he fits in and if he is by nature a risk-taker or staying away from risks.
The Emeralds are also the people that love statistics and numbers/facts. Rubies (the ones taking the most risk) won’t look at these statistics, so producing more stats won’t help them.
I am a Diamond!
I take risks where i think it is appropriate and intelligent to take the risk. I don’t see that “taking risks” is something valuable in itself. I DO fly to Sweden over water, because it is a calculated risk and I know that i can reach both shores in the glide flying high enough. I do not fly IFR in IMC across the Alps at night, because it will be just as much fun the next morning, and less risky.
Statistics? Does it inform our flying?
No! Well, of course it does some way or the other, but not my flying. Numbers like 1 in 100 000 hours means nothing, you cannot have any type of personal relation that will change your behavior based on such a numbers. You have to look at what causes accidents, then create rules of thumb that prevents you from flying into such situations. Airmanship I believe it is called. Looking at accident rates it is very simple: Avoid flying VFR into IMC, and avoid emptying your fuel tanks while flying, and the 1 to 100 000 has already decreased to 1 to 10 000 000.
Besides. For me, flying is a hobby. I don’t fly to be safe, I fly to have fun. This doesn’t mean I want to look death in the eyes every time I fly, but it means that safety is not my main concern. Still, I want to do things properly and correct, call it vanity or whatever, so Airmanship is a major concern. I have no urge to look stupid doing stupid things. I have flown in conditions in the mountains of Norway that I know for a fact will cause most of you here to just shake your heads, but there is no real danger in it, if you know how to handle the aircraft.
Norwegians are very found of outdoor activities. We walk in the mountains, summer and winter. We live in boats at summer time, travel around the world in small sail boats and so on. We have simple rules of thumbs for all these activities, and we all know that not following these rules are acts of personal stupidity. What strikes me, is the statistics. One out of two accidents in the mountains are German of French tourists freezing to death because they didn’t follow one or several of those rules. One out of two of accidents at sea are German or Polish tourists hobby-fishermen that didn’t follow one or several of those rules. Equally, one out of two accidents in small airplanes are German pilots flying VFR into IMC crashing in some mountain. I would call all these accidents pure stupidity, and so would most other of my fellow countrymen. My point is, accidents are caused by ignorance (stupidity), and the only way to keep these accidents to a minimum is to educate people, teach them right and wrong, and hope it sticks. If it don’t stick, well people have a right to be stupid, and there is nothing anyone can do to prevent it.
Those personality tests don’t take proper account of a person’s intelligence. And intelligence is important if one is to understand the risks in aviation.
For example, a Sapphire (which in another personality classification system is more descriptively called a Cheer Leader) could be anybody from a complete air-head, to somebody who is positive but intelligent and thus competent in applying it.
Many years ago I used to go out with a Cheer Leader air-head who worked in a company doing trade promotions, of ~200 people of whom all 200 were recruited for that profile. The result was apparently a very positive atmosphere at work, a fun place to work, a fair number of big screwups took place (which had to be fixed by a small number of another profile called Cogitator) and most people in there were screwing somebody at work (and as always everybody who was there for more than 1 day knew who was screwing who) 
Would such a person be a bad pilot? Only if they were stupid, which I guess many Cheer Leaders will be because being positive about everything goes with a lack of appreciation of consequences of one’s actions. Life is full of negatives and one has to deal with them too. But they aren’t all stupid, and a clever one can go a long way because he/she can make a good leader. But – in a corporate environment – only if he/she recruits a number of Cogitators who periodically clear up the mess
I think risk appreciation in aviation is more subtle and is to do with always leaving oneself a way out. There is for example no problem with crossing lots of water if you carry a raft, because the chances of an engine failure and the raft not working are very small. But only providing the sea doesn’t have 50ft waves on it… The people who kill themselves are invariably those who left themselves no way out, and then something bad happened. There are some cases of complicated sheer bad luck but they are very few.
There are also unusual incentives to risk stuff. Avoiding the IFR route charges by scud running below CAS kills a number of IR holders. Flying with near-empty tanks to get cheap fuel is another one.
So I think this business doesn’t lend itself well to being guided by statistics.
Even simple stats like engine MTBF can vary widely according to operating practices, who overhauled the engine, and simple bad luck.
a Pearl, Sapphire, Ruby and Amerald
What the difference with the four humores mankind has known since Ancient Greece, at least? But as Peter said, intelligence is another factor.
LeSving,
Germany’s highest mountain is 500 meters higher than Norways, so maybe you shouldn’t generalize (“germans”) that much. I bet that (southern :-)) Germany has just as much Mountain Climbing and outdoor tradition as Norway.
;-)
Germany’s highest mountain is 500 meters higher than Norways, so maybe you shouldn’t generalize (“germans”) that much
It’s not the height of the mountain tops that counts, but the height of the cloud base and the visibility below. Those basic rules of thumb should be self evident, they are dead simple things like: Prepare yourself, study the weather forecast, wear proper clothes, listen to experienced locals, tell others where you are going and so on (for walking in the mountains). But when people chose to ignore such basic wisdom simply because “we have higher mountains in France” (or Germany ), I mean, what can you do? It’s the same with flying. If you have no knowledge of what the actual risks are, or how to mitigate them, or simply chose to ignore it all together, then all the statistics in the world won’t tell you anything useful. Flying is potentially very risky, the clue is to know what the risks are and how to handle them. Once you do, only bad luck can bring you down, and there is no antidote for bad luck, so there is nothing to worry about. There is an other part to this as well. When you are accustomed to handle the risks, there are virtually no limits to what you can do, and get away with (if you are not struck by bad luck )
Yes… I looked at the statistics for autogyros, and decided they weren’t for me. I looked at all the NTSB accidents involving Vari-Ezes or Long-Ezes and decided that the fatality rates of off-runway landings (at least an order of magnitude greater than for Piper Cubs) made them another no-go area, much as I love to look at them.
But that said, one of my worst aviation purchases was a book called ‘The Killing Zone’ which was written by a statistical illiterate and published by an academic publisher at academic prices. Some parts of the book are good, where it describes the most common factors that cause accidents. But other books (e.g. ‘That worst day’ compendiums) do this at least as well, more cheaply and in what I consider to be a more memorable format.
For a few questions, where the statistics are most abundant and the answers most stark, statistics have some utility. But by and large general aviation data are too limited to draw any firm conclusions from them. Partly because in absolute numbers crashes are mercifully rare. Partly because they generally fail to provide much information that might enable us to allow for the characteristics of different types of pilot or operation in our analyses. And partly because the denominators i.e. number of hours flown by different types, are generally very sparse.
I agree with LeSving on this one. (Sweden’s outdoor culture is similar to Norway’s and so are the mountains.)
