Have you seen the television show on TruTV titled “Adam ruins everything” where Adam Conover destroys our perception of everything from green technology to the real origins of Christmas.
Here is my attempt to do just that with statement we all are
led to believe namely,
It is safer to fly than to drive
You have heard the old saying: “You are more likely to get
killed driving to the airport than flying on the plane” then people will go
on and on about how much safer it is to fly than to drive.
But is this really safer to fly than to drive? Not really!
Fact: You are over 280% more likely to die in a plane crash
than driving in a car.
How can that be…….are
the experts wrong?
I believe it is because experts are using a flawed metric
namely, miles:
When you look at the statistics online, most all articles use
the metric of “miles.”
For example, there are “X” number of deaths per million miles
for a car and there are “Y” number of deaths per million miles for a
commercial flight.
Passenger Mile?
First, the concept of a passenger mile, although used in the travel
industry, can certainly skew the numbers (to the positive) to the extreme. For example, if a flight with 500 passengers
travel from Los Angeles to New York (approximately 2400 miles), then the statisticians would say that flight had 1.2 million
passenger miles. With around 34000
flights a day, that is tens of billions of passenger miles a day. Certainly there are
millions of miles traveled by the big commercial airliners in the U.S.
everyday…but not BILLIONS.
This creates the case where you have a very large denominator in the equation (# of deaths / passenger mile) and the larger the denominator, the smaller the overall chances are they say.
This creates the case where you have a very large denominator in the equation (# of deaths / passenger mile) and the larger the denominator, the smaller the overall chances are they say.
Also, due to the jet
stream, distances between destinations on the ground and in the air are different.
For example, a flight from the west coast to the east coast
despite being the same miles apart will be a quicker flight (i.e. reducing the
chance of dying in a plane because you are in it a shorter period of time) That
same exact flight from east to west will be longer (i.e. increasing the chance
of dying in a plane because you are in the plane longer.) In a car, driving 100
miles at 50 miles per hour would take you 2 hours while driving that same 100
miles at 40 miles per hour would take you 2.5 hours. Using their logic, the
risk of getting in an accident are exactly the same, whereas I argue that the
2.5 hour trip would give you an extra half hour for something to go wrong.
Also, someone can certainly die in a car without having traveled
any miles or an airplane without it flying any distance yet.
Most importantly:
- Pilots training time (which has a significant impact on safety) is logged in flight hours…not miles
- Airplane maintenance schedules (which has a significant impact on safety) are in flight hours…not miles
Why shouldn’t our metric be something we can make most common
to each.
To eliminate as much variation as possible I will use the
most consistent metric regardless of anything else, which is time. The total time in an airplane and total time in a
car….regardless of the actual miles traveled.
Automobile results
There is an average of 220 million cars on the road on any
given day in the United States for an average of 1.5 hours each. Multiplying these two numbers gives us the
total number of “Car Hours” per day in the United States. The actual number is
330 million car hours / day.
Annually
there are about 34000 car deaths, which make the daily average for car deaths
about 93 per day. If you want to determine the number of car deaths per car hour,
you simply divide 93 car deaths by 330 million car hours. The number is 0.00000028 (deaths / car
hour). This also represents the
probability that you will die in a car accident in one hour of driving or the
odds are 3,533,568 to 1.
Please note: This is not the same as deaths per
hour…..it is deaths per car hour.
To determine the number of deaths per hour, you would divide 93 daily
deaths by 24 hours, which is 3.8 deaths per hour somewhere in the United States.
Commercial Airline
results
There is an average of 34,000 commercial flights in the
United States every day with an average flight time of let’s say 2.5 hours….some
are more and some are less but 2.5 hours is a conservative number (that is
about the same as flying from Phoenix to Portland. In actuality there will be years pass with no
major incidences and then, unfortunately, there will be an accident resulting
in many deaths…but if you average up the previous 10 years or so….you will
arrive at a number anywhere from 25 – 35 per year or so, but for our purpose…I
use 25 airline deaths per year to be conservative and skew the numbers to be "safer".
Multiplying these 34,000 commercial flights and 2.5 hours gives
us the total number of “Flight Hours” per day in the United States. The actual
number is 85,000 Flight hours / day.
Annually there are about 25 commercial flight deaths annually, which
make the daily average for commercial flight deaths at about 0.0685 per day. If
you want to determine the number of commercial flight related deaths per flight
hour, you simply divide 0.0685 deaths by 85,000 flight hours. The number is 0.00000081 (Deaths / flight
hour). This also represents the
probability that you will die in a commercial flight in one hour of flying or
the odds are 1,234,566 to 1.
Please note:
This is not the same as deaths per hour…..it is deaths per flight
hour. To determine the number of deaths
per hour, you would divide .068 daily deaths by 24 hours, which are 0.0028
deaths per hour.
Do you see it…..the odds of dying in a car hour is 3,533,568 to 1
while the odds of dying in a flight hour are 1,234,566 to 1!
The chances of being killed in any one hour on a plane are 286%
greater than that in a car.
The perception that planes are safer, in my opinion, stem from the
fact that there are far fewer airplanes flying than there are cars driving.
With a whopping 220 million cars on the road daily with only 34,000 commercial
flights it’s no surprise there are more car related accidents…
But what would it look like if the number of flights hours equaled
the number of car hours per day…that is to say, what if there were 361,644
flights a day in the United States….
There would be over 97,000 commercial airline deaths a year…that
is about 260 deaths each day…..basically a commercial jetliner crashing almost
daily.
It’s all about how you present it….rhetoric if you will, to
persuade others to believe something or infer that because one scenario is
safer…all scenarios are safer.
For example, if you said the following:
”You are more likely to die in a car crash while driving from Los Angeles to New York than flying from Los Angeles to New York.”
Then yes, that would be correct……WHY…..because it takes almost 800% more time to drive than to fly to New York from Los Angeles, therefore increasing your chance of dying in a car crash.
”You are more likely to die in a car crash while driving from Los Angeles to New York than flying from Los Angeles to New York.”
Then yes, that would be correct……WHY…..because it takes almost 800% more time to drive than to fly to New York from Los Angeles, therefore increasing your chance of dying in a car crash.
In reality both driving and flying are extremely safe. The actual odds of dying in a 2.5 hour plane
ride are still very small (about 1:500,000 in my example.)
To give you some perspective on how remote this is....the chances of a person being struck by lightning in their lifetime is about 1:3000
You could spend your entire life riding on an airplane (and never getting
off) and still not ever crash…..but to say that flying is safer than
driving is not accurate.
Still don’t believe it. Take a look at any top ten most “Dangerous Jobs” list and see that airline pilots always rate more dangerous than professional drivers.
All of my referenced statistics were obtained from legitimate
sources found on the internet.
I encourage you to play around with my numbers.
Be more conservative….or less conservative with my averages and see that this
is the case.
No comments:
Post a Comment