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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. Sa

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.
    - cameronh90 5y ago
      I think we are in agreement with the the situation, I just disagree and think you're either driving too fast or following too close. Your logic leads to pile ups, as in the event of a pile up, a car stops dead unexpectedly infront of you and you have nowhere to swerve. I can't speak for the USA, but in the UK, if someone swerves and you rear end a stationary object, you are at fault. Indeed if you rear end another vehicle, you are nearly always at fault (unless e.g. they pulled in front of you then immediately slammed the brakes). For stopping distances, this is what we are taught in the UK (rule 126): https://www.gov.uk/guidance/the-highway-code/general-rules-techniques-and-advice-for-all-drivers-and-riders-103-to-158 https://www.gov.uk/guidance/the-highway-code/general-rules-t... Stopping distance at 70mph is about 100m and "The safe rule is never to get closer than the overall stopping distance". This is a minimum - in adverse conditions the distance should be even greater. This means when you see the stationary object, you're about 100m away, which is adequate time to stop IF you're paying attention and your car is well maintained (we have annual MOTs to ensure this).
- cameronh90 5y ago
  I don't know about the USA, but in the UK our stopping distances assume the car might become stationary at any point. That is, they are actually stopping distances - not following distances. If you follow closer than that on your test, you will fail.
falcolas 5y ago
Frankly, I can never imagine seeing an empty football field worth of space between two cars on a busy freeway. Even if you attempt to create such a space, other drivers will fill it. This assertion about following distance feels purely theoretical for busy freeways.
- cameronh90 5y ago
  Caveat: I drive in the UK so driving quality may be different here. I always maintain adequate stopping distances on busy motorways. People do fill those gaps occasionally and it does result in me driving slightly slower on average by a couple mph maybe, but it's perfectly possible to maintain a gap. A lot of experienced drivers here claim it's impossible too, but there's a good way to know that it's not: on your driving test, you'll fail for following too closely, so most people manage to keep an adequate stopping distance for the test. Following closely is usually a habit picked up when someone becomes a more confident driver. The real reason is probably people don't want to take the tiny average speed hit or find it unfair that they keep letting people in.

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.
  - cameronh90 5y ago
    I think we are in agreement with the the situation, I just disagree and think you're either driving too fast or following too close. Your logic leads to pile ups, as in the event of a pile up, a car stops dead unexpectedly infront of you and you have nowhere to swerve. I can't speak for the USA, but in the UK, if someone swerves and you rear end a stationary object, you are at fault. Indeed if you rear end another vehicle, you are nearly always at fault (unless e.g. they pulled in front of you then immediately slammed the brakes). For stopping distances, this is what we are taught in the UK (rule 126): https://www.gov.uk/guidance/the-highway-code/general-rules-techniques-and-advice-for-all-drivers-and-riders-103-to-158 https://www.gov.uk/guidance/the-highway-code/general-rules-t... Stopping distance at 70mph is about 100m and "The safe rule is never to get closer than the overall stopping distance". This is a minimum - in adverse conditions the distance should be even greater. This means when you see the stationary object, you're about 100m away, which is adequate time to stop IF you're paying attention and your car is well maintained (we have annual MOTs to ensure this).
cameronh90 5y ago
I don't know about the USA, but in the UK our stopping distances assume the car might become stationary at any point. That is, they are actually stopping distances - not following distances. If you follow closer than that on your test, you will fail.

falcolas 5y ago

Frankly, I can never imagine seeing an empty football field worth of space between two cars on a busy freeway. Even if you attempt to create such a space, other drivers will fill it. This assertion about following distance feels purely theoretical for busy freeways.

cameronh90 5y ago
Caveat: I drive in the UK so driving quality may be different here. I always maintain adequate stopping distances on busy motorways. People do fill those gaps occasionally and it does result in me driving slightly slower on average by a couple mph maybe, but it's perfectly possible to maintain a gap. A lot of experienced drivers here claim it's impossible too, but there's a good way to know that it's not: on your driving test, you'll fail for following too closely, so most people manage to keep an adequate stopping distance for the test. Following closely is usually a habit picked up when someone becomes a more confident driver. The real reason is probably people don't want to take the tiny average speed hit or find it unfair that they keep letting people in.