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A few months back I got a call from Tesla inviting me to the Cybertruck reveal event,
and if you listen closely you can hear my reaction in the audience.
“Hahahahahahha what on earth is that?! Elon you absolute lunatic go home to yer mother.”
Okay I lied. I’m not cool enough to get invited to influencer events, but that was
my initial reaction, though honestly, the design has grown on me in the past month or
so. However I do have one major concern with the design. Its safety. It’s cold rolled
stainless steel unibody design just doesn’t sound like it has been designed with traditional
safety ethos in mind.
They showed that the panels don’t deform and bend when hit with a sledge hammer, which
is great if you have a habit of being attacked by sledge hammer wielding car designers. But
in the event of a crash, at least according to my understanding at the time, was that
vehicle panels are designed to crumple and deform in a crash in order to absorb kinetic
energy and slow the rate of deceleration to a survivable level.
Instead of jumping to conclusions, I decided to jump into research mode and see how vehicle
safety is actually evaluated and in the process learn what the most dangerous car on the road
is. What I discovered along the way was truly eye opening.
Trying to quantify what the most dangerous car is, is actually a surprisingly difficult
task.
Total annual road deaths peaked in the early 70s as the number of miles being driven rose
while vehicle safety was not yet a high priority. Using this raw statistic is not terribly useful
for analysing vehicle safety, as there are far too many variables that can affect it.
For example here we can see a massive dip in deaths in world war 2 as fuel rationing
began.
So let’s plot this in a different way. Let’s plot the deaths per billion miles travelled.
This allows us to parse out any variations in road use at the very least.
Now we can see a real trend, over the past 100 years vehicle safety has continually improved.
Total road deaths even managed to decline in the 70s as the NHTSA began testing vehicle
safety, which forced manufacturers to put a bigger focus on survivability..
It’s clear road safety has risen dramatically, thanks to technology and policy improvements,
but that doesn’t mean there isn’t room for improvement.
The question I had was “How do we define an unsafe car”. It’s a surprisingly difficult
thing to quantify. We are going to use US data simply because it is the most easily
accessible data, but there will be some cultural variables we need to consider in this, especially
with American’s fondness for trucks that wouldn’t fit down most European streets.
The most obvious starting point would be to identify the vehicles with the most occupant
fatalities using the Fatality and Injury Reporting System Tool website. [2]
Actually compiling data from this site is a little labour intensive, but thankfully
iseecars have created a report on this already. [3]
Here’s what they found. The top 14 most dangerous cars by most occupant fatalities
per billion miles were all subcompact, compact and sports cars.
This does not give us a whole lot of useful data. 6 of the top 14 are sports cars, which
are likely more dangerous because of the way people drive them, another human variable
we need to consider. While the most dangerous car by this measure is the Mitsubishi Mirage.
This tiny thing. Is that our answer? That driving a small car in a country obsessed
with trucks is dangerous.
This thing is, despite its size, it fared okay in America’s car safety rating systems.
The national highway traffic safety administration’s gave it a score of 4 stars out of 5. [4] While
the Insurance Institute of Highway Safety gave it an overall positive review [5] only
getting a “poor” rating for this test. The small overlap frontal impact test because
the dummy’s head managed to slip off the airbag and hit a pillar, while the footwell
deformed too much potentially causing damage to the lower body.
For me, these results are not indicative of a vehicle that has over 4 times the national
average of occupant fatalities, and that certainly isn’t because it can carry more occupants.
It certainly isn’t going to dissuade your average mother from using it to drive their
kids to school.
Let’s dive into the testing systems to see if we can unearth the cause of this strange
discrepancy.
For now let’s focus on frontal crash tests, as it is the scenario where most fatal crashes
occur.
The National Highway Traffic Safety Administration’s test measures the likelihood for driver or
passenger injury when a vehicle crashes into a fixed barrier at 35 miles per hour. The
IIHS’s tests are slightly different, partially because they were created to improve on NHTSA’s
tests which were created in the 70s.
They increased the test speed to 40 miles per hour and made the impact area smaller.
Both of these moves were intended to make the test harder to pass, and that showed with
the Mirage’s poor performance, but that poor performance was mostly down to it’s
airbags not overlapping enough. The 2017 Mirage model corrected this problem by increasing
the length of the side curtain airbag.
That increased difficulty resulted in a critical design issue being identified and fixed. Yet
the NHTSA’s tests, America’s government run testing program, has not changed since
the 1970s. [6]
Just to make it crystal clear why that is an absolutely shocking revelation. This is
an IIHS test showing a 1959 Chevy Bel Air into a 2009 Chevy Malibu. The crash test dummy
of the Bel Air is smashed as the steering column gets forcefully pushed into the driver's
seat. Modern cars avoid this because the steering column has been designed to torsionally stiff
to allow steering, but is designed to collapse when force is placed on it in the longitudinal
direction. [7]
The Bel Air had no airbags, a standard safety feature today. It also has no headrests to
prevent whiplash and no seat belts. These are the kind of cars the 1970s test was made
to test for. It is not fit for purpose for today’s cars.
Today nearly all vehicles today are rated 4 or 5 stars. Which makes the job of avoiding
a vehicle with a terrible safety record, like the Mitsubishi Mirage, a very difficult job.
It’s time the tests were made more difficult again. The frontal test for the NHTSA is set
at 35 miles per hour, but the force of impact is not solely determined by the speed of impact,
it’s also determined by the weight of the vehicle. This test only simulates the impact
of two identical weight vehicles.
That’s not good enough for a car that is intended to drive in a country where the most
popular car is the ford f-series, a truck that is twice the weight of the mirage.
This is just one obvious oversight in their testing methods, but there are countless other
issues with the state of safety testing today. For example, crash test dummies are all based
on the average adult man.
Tests for the average adult woman do not exist, which is odd considering women constitute
50% of the American population AND currently have a 47% higher chance of serious injury
in a frontal crash. [8] The only variable there is the driver is a woman. Let that sink
in. 47%. That is insane. Part of that statistic is due to men having higher bone densities
among other anatomical differences that make men less likely to be injured. That is unavoidable,
but if anything that’s a reason to design with women in mind.
Simple things like the IIHS’s test for whiplash uses the maximum possible neck deflection
as a result of headrest design, but it only tests it using an average male dummy. That
test doesn’t exist in NHSTA’s tests and when IIHS introduced it it forced automakers
to design better headrests to prevent whiplash, but it forced them to design better headrests
for men, not women. One of the most common injuries resulting from a car crash even today,
because headrests are not often adjusted for the individual driving.
Maybe if the testing used a larger variety of crash test dummies it would force automotive
companies to introduce automatically adjusting headrests as part of a standard safety package,
which have been a feature in some vehicles. That’s just a simple example, but by testing
both female and male dummies it will force automakers to make their cars safer for all
road users.
These archaic tests do not just make it difficult to identify the most dangerous car. They make
it difficult to identify the safest, which is the true goal. Automotive makers making
real efforts to improve safety are simply not being acknowledged in these tests.
Tesla’s cars perform incredibly well in frontal crashes because there is no engine
block, allowing the entire front section to act as a crumple zone. Tesla’s has autobrake
and warning sound features that help prevent crashes all together. It’s score: 5 stars.
1 star separates the NHTSA's testing of a vehicle that has 4 times the national average
of occupant fatalities and a vehicle which features massive leaps in occupant safety.
That needs to change, soon. For now, if you are looking to buy a safe vehicle I recommend
you avoid NHTSA results altogether. They are useless. There are international tests like
the European NCAP, which test for more things but still rated the Mirage with 4 stars. The
Insurance Institute of Highway Safety test has been continually adding new tests. They
test for auto braking and few other modern safety features and they should be applauded
for that. Their rating system is superior to any I have seen, but can be a little confusing
for the consumer.
Their superior tests also don’t stop automakers with poor safety design from using the NHTSA's
archaic testing and rating procedures in their marketing. I only discovered these flaws in
the rating system because it is literally my job to research these things. That cannot
be expected of the average consumer.
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