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So, the car in front was able to swerve, but from 2 cars back, he couldn’t and ended up killing a person. Somebody wasn’t paying attention. Not they he’s unique

So, the car in front was able to swerve, but from 2 cars back, he couldn’t and ended up killing a person. Somebody wasn’t paying attention. Not they he’s unique in this, but his statement is baloney.

TeeWEE 5y ago
Even at a save distance, if the car was at a complete standstill, thats something completely unexpected on the highway. Having to react in such a short timeframe is close to impossible for a human, even when you keep a "safe distance" The "safe distance" is only "safe" if all the traffic is moving at least.
- notreallyserio 5y ago
  I've seen cars at a complete standstill on the highway more than once. It's fair to say it is unusual but it should be fully expected, IMO. I don't understand the scare quotes around safe distance here. Maintaining safe distance (and the implied safe speed and open eyes) absolutely would help in these situations.
Aeolun 5y ago
Car in front saw the car before them suddenly start to brake, but Tesla was still moving fast enough to get out of the way. Which revealed an almost stationary car to the person behind, whom was still driving 70mph. I can see how that is hard to react to. I wasn’t sure how hard though, so I did a thought experiment. Say there is 50m between each car, and they’re all driving 25m/s. First car starts braking at 5ms. After one second the distance between 1 and 2 is 45m. After two seconds, 35m. After 3s, 20m, and the car is evading. After 4s, car 2 is passing by 1, whom is now moving at only 5m/s. Car 1 is finally revealed to car 3, who now has a maximum of two seconds to do something before it crosses the 50m gap. And that’s assuming an adequate gap. They were likely closer.
rootusrootus 5y ago
Have you ever had someone in front of you swerve out of the way, leaving you facing a stopped car? It's exciting, let me tell you. The idea of safe following distance is predicated on the car in front of you not being able to defy physics when they stop, presumably their braking power is similar to yours.
- cameronh90 5y ago
  Yes. But because I was following at a safe distance from the car in front, that gave me adequate time to slow down and stop without hitting the stopped car. Safe following distance isn't predicated on defying physics, it means assume the car in front might stop dead for any reason - hitting an unseen obstacle, swerving to reveal an obstacle, sudden mechanical failure, animal collision, whatever. The distance you need to react and stop is around 100 metres at 70mph. Therefore, that's the distance you should keep from the car in front. As a bonus, it gives any tailgaters more time to notice you're slowing down too. Hopefully this means you're less likely to get pancaked between two cars.
  - Lascaille 5y ago
    >Safe following distance isn't predicated on defying physics, it means assume the car in front might stop dead for any reason No, it's based on assuming the car in front might brake at standard non-physics-defying rates at any time. The 'safe' following distances that are advised don't allow for encountering stationary objects. That's why they're called following distances, as in, you're following another vehicle that obeys the laws of physics.
    - alistairSH 5y ago
      But that Tesla didn't defy physics. Nor did it fall out of the sky. It braked and slowed like any other car. Maybe there truly wasn't enough time to completely avoid a crash. But there should have been enough time to avoid a serious (deadly) crash.
      - Lascaille 5y ago
        >It braked and slowed like any other car. Imagine you're following - at a safe distance - a vehicle. The driver of the vehicle you're following doesn't notice that the car ahead of them is emergency braking. They notice at the last second and swerve around it to avoid a collision. You are then face to face with a nearly-stationary object which was concealed from you by the vehicle ahead of you. From your perspective, it fell from the sky. If you don't swerve, a collision is unavoidable.
jhoechtl 5y ago
The question is whether the accident would still have happened, if the second car drove a Tesla, also with the autopilot engaged?

TeeWEE 5y ago

Even at a save distance, if the car was at a complete standstill, thats something completely unexpected on the highway. Having to react in such a short timeframe is close to impossible for a human, even when you keep a "safe distance" The "safe distance" is only "safe" if all the traffic is moving at least.

notreallyserio 5y ago
I've seen cars at a complete standstill on the highway more than once. It's fair to say it is unusual but it should be fully expected, IMO. I don't understand the scare quotes around safe distance here. Maintaining safe distance (and the implied safe speed and open eyes) absolutely would help in these situations.

Aeolun 5y ago

Car in front saw the car before them suddenly start to brake, but Tesla was still moving fast enough to get out of the way. Which revealed an almost stationary car to the person behind, whom was still driving 70mph. I can see how that is hard to react to. I wasn’t sure how hard though, so I did a thought experiment. Say there is 50m between each car, and they’re all driving 25m/s. First car starts braking at 5ms. After one second the distance between 1 and 2 is 45m. After two seconds, 35m. After 3s, 20m, and the car is evading. After 4s, car 2 is passing by 1, whom is now moving at only 5m/s. Car 1 is finally revealed to car 3, who now has a maximum of two seconds to do something before it crosses the 50m gap. And that’s assuming an adequate gap. They were likely closer.

rootusrootus 5y ago

Have you ever had someone in front of you swerve out of the way, leaving you facing a stopped car? It's exciting, let me tell you. The idea of safe following distance is predicated on the car in front of you not being able to defy physics when they stop, presumably their braking power is similar to yours.

cameronh90 5y ago
Yes. But because I was following at a safe distance from the car in front, that gave me adequate time to slow down and stop without hitting the stopped car. Safe following distance isn't predicated on defying physics, it means assume the car in front might stop dead for any reason - hitting an unseen obstacle, swerving to reveal an obstacle, sudden mechanical failure, animal collision, whatever. The distance you need to react and stop is around 100 metres at 70mph. Therefore, that's the distance you should keep from the car in front. As a bonus, it gives any tailgaters more time to notice you're slowing down too. Hopefully this means you're less likely to get pancaked between two cars.
- Lascaille 5y ago
  >Safe following distance isn't predicated on defying physics, it means assume the car in front might stop dead for any reason No, it's based on assuming the car in front might brake at standard non-physics-defying rates at any time. The 'safe' following distances that are advised don't allow for encountering stationary objects. That's why they're called following distances, as in, you're following another vehicle that obeys the laws of physics.
  - alistairSH 5y ago
    But that Tesla didn't defy physics. Nor did it fall out of the sky. It braked and slowed like any other car. Maybe there truly wasn't enough time to completely avoid a crash. But there should have been enough time to avoid a serious (deadly) crash.
    - Lascaille 5y ago
      >It braked and slowed like any other car. Imagine you're following - at a safe distance - a vehicle. The driver of the vehicle you're following doesn't notice that the car ahead of them is emergency braking. They notice at the last second and swerve around it to avoid a collision. You are then face to face with a nearly-stationary object which was concealed from you by the vehicle ahead of you. From your perspective, it fell from the sky. If you don't swerve, a collision is unavoidable.

jhoechtl 5y ago

The question is whether the accident would still have happened, if the second car drove a Tesla, also with the autopilot engaged?