planes vs cycles

"PaulH" wrote in message
m...
I've seen statements in various aviation chat rooms that the GA
accident rate is similar to that of motorcycles, but have never seen
the actual statistics. Is this GA overall? Accidents per hour or per
mile? Incidents or fatalities?

Gary already provided a reference for aviation statistics. You can find
motorcycle statistics on the NHTSA web site, and probably some other
government sites (seems like I came across a "US Bureau of Statistics" web
site). I don't recall the URLs off the top of my head (though the NHTSA is
probably www.nhtsa.gov) but last time I went looking for this stuff, it was
very easy to find using Google.

I'll just add that it's important to keep in mind that it's very difficult
to make "apples to apples" comparisons. You need to decide whether you're
going to compare miles, time, or number of trips, and whether you're going
to do those comparisons using the vehicle count or the passenger count.

Invariably, someone will disagree with your choice, so you just have to pick
the one that you think is relevant to you. Also, "GA" encompasses a wide
range of operations, from corporate aviation (very safe) to water bombing
fires (not very safe). Even within the "four seater lightplane recreational
flying" category, different types have varying safety records, affected by
"typical mission", landing speed, crash survivability, and the like.

With all that variability, you also need to decide what "similar" means to
you. Some people will say that as long as the accident rates are about the
same order of magnitude, they are similar. Other people will say that they
are only similar if they are within 10% of each other.

Anyway, it's my opinion, having looked at the various accidents rates
myself, that motorcycles and light airplanes have similar fatality rates,
while automobiles are somewhat better. Generally speaking, the fatal
accident rate seems to have more to do with how easily one can survive a
crash in a particular kind of vehicle than it does with how often accidents
actually happen.

Finally, keep in mind that with motor vehicles, for every accident that
involves more than one vehicle, most of the time one of the operators of the
vehicles had no way to avoid the accident, it being caused by the operator
of the other vehicle. In aviation, airplane accidents almost always involve
just one occupied aircraft. In my opinion, this makes a given accident rate
effectively "less worrisome", since as the pilot I have more control over my
destiny. That doesn't necessarily make me *safer*, but it makes me
*happier*.

Pete

Peter Duniho wrote:

"PaulH" wrote in message
m...

I've seen statements in various aviation chat rooms that the GA
accident rate is similar to that of motorcycles, but have never seen
the actual statistics. Is this GA overall? Accidents per hour or per
mile? Incidents or fatalities?

I'll just add that it's important to keep in mind that it's very difficult
to make "apples to apples" comparisons. You need to decide whether you're
going to compare miles, time, or number of trips, and whether you're going
to do those comparisons using the vehicle count or the passenger count.

Agreed. Here's one comparison based on number of fatalities per million
hours spent in a variety of activities (incl. GA and motorcycling):
http://www.magma.ca/~ocbc/comparat.html

Obviously distance travelled is a key issue and I do understand the need for
an 'apples and apples' comparison. However, in the UK we have been
averaging 18 GA accidents a year (which icludes higher risk types such as
autogyros and balloons) compared to a steady 3,500 deaths a year through
road traffic accidents. Only a serious statistician could make any
meaningfull comparisons from these different forms of transport but I do
think that things should be kept into perspective. i.e. if you are
concerned about accidental death where could your efforts save the most
lives GA or car?

Andy



"Peter" wrote in message
...
Peter Duniho wrote:

"PaulH" wrote in message
m...

I've seen statements in various aviation chat rooms that the GA
accident rate is similar to that of motorcycles, but have never seen
the actual statistics. Is this GA overall? Accidents per hour or per
mile? Incidents or fatalities?

I'll just add that it's important to keep in mind that it's very
difficult
to make "apples to apples" comparisons. You need to decide whether
you're
going to compare miles, time, or number of trips, and whether you're
going
to do those comparisons using the vehicle count or the passenger count.

Agreed. Here's one comparison based on number of fatalities per million
hours spent in a variety of activities (incl. GA and motorcycling):
http://www.magma.ca/~ocbc/comparat.html

I of course refer to the average of 18 fatal accidents each year - there of
course many more non fatal ones!

"Andy Fogg" wrote in message
...
Obviously distance travelled is a key issue and I do understand the need
for
an 'apples and apples' comparison. However, in the UK we have been
averaging 18 GA accidents a year (which icludes higher risk types such as
autogyros and balloons) compared to a steady 3,500 deaths a year through
road traffic accidents. Only a serious statistician could make any
meaningfull comparisons from these different forms of transport but I do
think that things should be kept into perspective. i.e. if you are
concerned about accidental death where could your efforts save the most
lives GA or car?

Andy



"Peter" wrote in message
...
Peter Duniho wrote:

"PaulH" wrote in message
m...

I've seen statements in various aviation chat rooms that the GA
accident rate is similar to that of motorcycles, but have never seen
the actual statistics. Is this GA overall? Accidents per hour or per
mile? Incidents or fatalities?

I'll just add that it's important to keep in mind that it's very
difficult
to make "apples to apples" comparisons. You need to decide whether
you're
going to compare miles, time, or number of trips, and whether you're
going
to do those comparisons using the vehicle count or the passenger
count.

Agreed. Here's one comparison based on number of fatalities per million
hours spent in a variety of activities (incl. GA and motorcycling):
http://www.magma.ca/~ocbc/comparat.html

"Andy Fogg" wrote in message
...
Obviously distance travelled is a key issue and I do understand the need
for
an 'apples and apples' comparison. However, in the UK we have been
averaging 18 GA accidents a year (which icludes higher risk types such as
autogyros and balloons) compared to a steady 3,500 deaths a year through
road traffic accidents.

Those are absolute rates. They are meaningless without considering the
exposure to the risk. Which, of course, is what this entire thread is
about, basically.

18 fatal GA accidents per year would be a very big problem if there were
only 18 GA flights each year.


Only a serious statistician could make any
meaningfull comparisons from these different forms of transport but I do
think that things should be kept into perspective. i.e. if you are
concerned about accidental death where could your efforts save the most
lives GA or car?

It depends on who you are. If you are a person who will never fly in an
airplane, but who spends a lot of time on the highway, you will invest your
efforts in saving lives in cars. If you fly more than you drive, you
probably care more about GA fatal accidents.

The question isn't about where should safety measures be implemented. It's
about relative comparison of safety for various activities (motorcycling and
flying, in particular).

The analysis is, of course, very different if you're a person in charge of
public policy rule-making and budget-writing where you have to decide where
to invest your efforts. But that's an entirely different conversation than
the one we're having here.

Pete

The usual method for comparing the safety of automobiles is *drivers*
killed per million miles driven. (The Toyota Avalon is the safest
automobile, BTW.) That eliminates the skewing you get with passengers,
for example when comparing Dodge Caravans with Mazda Miatas.

Strikes me this would also be the only fair way to compare a
motorcycle and a lightplane.

all the best -- Dan Ford
email: (put Cubdriver in subject line)

The Warbird's Forum www.warbirdforum.com
The Piper Cub Forum www.pipercubforum.com
Viva Bush! weblog www.vivabush.org

"Cub Driver" wrote in message
...
Strikes me this would also be the only fair way to compare a
motorcycle and a lightplane.

It is fair if all you care about is the risk to the pilot.

It is not fair if you care about whether passengers survive. Just because a
vehicle carries more passengers, that doesn't mean it's unfair to take that
into account when comparing safety.

For example, personally, I think it's very relevant that an airline jet
might be carrying 100-300 passengers (depending on type) when it crashes.
They crash a lot less often, but when they do, they kill a lot more people
at once. That's not a fact you can just ignore, IMHO. (Of course, even
with this characteristic is taken into account, airliners are still way
safer than little planes).

Pete

Just because a
vehicle carries more passengers, that doesn't mean it's unfair to take that
into account when comparing safety.


Depends how you are measuring "safety", what you are comparing it to, and to
what end.

If there's only two airliner flights in a year, each carrying 300 passengers,
one crashes, and they all die.... and there's only two motorcycle trips in that
same year, and one crashes, killing the rider, is the plane really 302 times
more dangerous than the motorcycle?

Are you 302 times more likely to die in a plane crash than by riding a
motorcycle?

Jose

--
(for Email, make the obvious changes in my address)

"Teacherjh" wrote in message
...
Depends how you are measuring "safety", what you are comparing it to, and
to
what end.

If there's only two airliner flights in a year, each carrying 300
passengers,
one crashes, and they all die.... and there's only two motorcycle trips in
that
same year, and one crashes, killing the rider, is the plane really 302
times
more dangerous than the motorcycle?

I never said anything about making relative comparisons. I'm just pointing
out that you can't say it's "not fair" to compare the two. Depending on
what information you're interested in, it might be completely fair.

As for your sample comparison, if you're looking for passenger-flight safety
numbers then yes, the airliner is 600 times "more dangerous" than the
motorcycle when measured in fatalities per trip (I don't know where you came
up with 302, since you failed to specify your units). Whether that's an
interesting comparison to someone is up to them to decide.

Are you 302 times more likely to die in a plane crash than by riding a
motorcycle?

Measured how? You haven't specified the units you're using, but assuming
you did the math right, then statistically speaking (using your obviously
statistically insignificant sample) the answer would be "yes". In your
example, the statistical difference would be explained as much by the
greater likelihood of actually riding in an airplane versus in a motorcycle,
and the units change once you make the assumption that the passenger is on
each, but with the parameters you've specified so far, airliners are
statistically more likely to kill a given person.

Pete

Cub Driver wrote:

The usual method for comparing the safety of automobiles is *drivers*
killed per million miles driven.

Which may be one reason it took years for passenger airbags to become common.

Strikes me this would also be the only fair way to compare a
motorcycle and a lightplane.

I disagree. A fatal accident is a fatal accident, even if the fatality is a
passenger. Personally, I would be more interested in the number of fatal accidents
per 1,000 hours, or similar stats. The general public would probably be most
interested in the number of fatalities (both passenger and crew) per 1,000 hours, or
perhaps the number of trips per fatality.

George Patterson
None of us is as dumb as all of us.