Tesla recently released a new update to its Vehicle Safety Report, revealing data for the fourth quarter of 2022.
The voluntarily published quarterly reports include the number of miles driven per one accident registered when using Autopilot technology, not using Autopilot technology, and the US average (NHTSA and FHWA data) as a background.
The data gives us glimpses of how Autopilot improves vehicle safety but it has some limitations (more on that at the bottom of this post) due to the methodology. For example, Tesla counts all accidents, regardless of the cause, despite the fact that more than 35 percent of all Autopilot crashes occur when the Tesla vehicle is rear-ended by another vehicle, the company says.
According to Tesla, the number of miles driven per one accident registered, when using Autopilot technology, amounted to 4.85 million miles driven – an 11.5 percent increase year-over-year. That’s a positive sign.
At the same time, the result was noticeably lower than in the previous three quarters, but we can’t really compare different seasons.
The most important thing is that there are fewer crashes registered every year, as far as fourth quarters are considered.
Without using Autopilot technology, Tesla vehicles statistically note more accidents. In Q4 2022, it was one accident per 1.40 million miles driven (8 percent more than a year ago).
There is a significant difference between the two modes of driving (with or without Autopilot) and the difference continues to increase.
However, we must note that the two data sets should not be compared against each other, aside from providing us with some idea of the numbers.
It’s important to note that the results are comparable only within a particular category (Autopilot or without Autopilot), not between the categories as the input data might be widely different (like simple highway driving or complex city driving). In other words, we can only see whether the active safety systems are improving over time (and it’s also only a rough comparison), but we can’t compare Autopilot to non-Autopilot driving.
We assume that the proper use of Autopilot improves safety, but Tesla’s report does not allow us to evaluate the difference.
Below we attached a full chart with all numbers provided by the manufacturer plus NHTSA and FHWA data about the average distance between an automobile crash in the United States.
The difference is pretty huge, but once again, we shouldn’t really compare the numbers directly. The US average includes also a much older vehicle fleet (with fewer safety systems), which alone is a big factor. The US average is 0.652 million miles (there has been no update in a long time).
Tesla has its own version of the chart:
Important factors:
- data for each setting might be collected at different driving scenarios (like simple highway driving or complex city driving), which makes the results incomparable between the categories
- results might be affected by various factors, including seasonality (reduced daylight, weather conditions), less driving during lockdown
- NHTSA and FHWA average for the US (updated rarely) includes all cars, also old
- Tesla’s info about the methodology of registering accidents:
“We collect the amount of miles traveled by each vehicle with Autopilot active or in manual driving, based on available data we receive from the fleet, and do so without identifying specific vehicles to protect privacy. We also receive a crash alert anytime a crash is reported to us from the fleet, which may include data about whether Autopilot was active at the time of impact. To ensure our statistics are conservative, we count any crash in which Autopilot was deactivated within 5 seconds before impact, and we count all crashes in which the incident alert indicated an airbag or other active restraint deployed. (Our crash statistics are not based on sample data sets or estimates.) In practice, this correlates to nearly any crash at about 12 mph (20 kph) or above, depending on the crash forces generated. We do not differentiate based on the type of crash or fault (For example, more than 35% of all Autopilot crashes occur when the Tesla vehicle is rear-ended by another vehicle). In this way, we are confident that the statistics we share unquestionably show the benefits of Autopilot.” - assuming the methodology was not changed, we can see how each category improves over time
