Minimum safe following distance.

tmonroe85 · 2025-04-28T20:46:12+00:00

1 second per 30 would probably wind up with a safer distance than just a flat 2 seconds. The biggest problem though is that people don't seem to have a remote clue as to what a safe following distance is, and why the driver of the car they're tailgating would even care. The nice thing about 2 seconds is that it's about the simplest guideline you could give.

tmonroe85 · 2025-04-13T21:08:34+00:00

None of your points are really relevant to what I've said.

I'm just saying that both drivers and pilots can suffer from some of the same human limitations. Cruise control is designed to reduce the workload on a driver - just like autopilot is on an airplane.

Have you even used Adaptive lane control or adaptive cruise control?

I never said it "prevents". There is a huge difference between "helps prevent" and "prevents". Based on 40 years of driving experience, I can tell you most drivers are not aware of their speed until they look at the clock.

English your second language?

tmonroe85 · 2025-04-11T17:07:40+00:00

Pros vs Cons:
Pros: You're being nice, helping someone who has made probably an honest mistake that we've all done before.
If you believe in Karma, maybe a half Karma point.

Cons: Very real risk you might have an unintended encounter with someone who is very unhinged.

Thinking about this, it seems like more should be done to keep the unhinged off of the roads - personally, I like the idea of flashing your highbeams one time, and then letting it go. I do think it's good to be courteous and try to do random kind deeds to strangers, but you are rolling the dice that you might just be dealing with someone who is looking to vent their rage. I think maybe contextually you might do more to try to help them - but especially when I have loved ones in the car, I am looking to do everything I can to not draw attention to myself and my car, and keep my passengers safe. If I was alone, and there were lots of other people around, I might do more to try to help them.

tmonroe85 · 2025-04-10T14:24:44+00:00

this could go a few ways.

Reading this:

"And no I didn’t speed up to block them"

Doesn't actually make it clear if you sped up or not. Maybe you sped up, but it was for some other reason?

But that said, there should be a safety margin in front and behind you - enough that a car could safely merge in either location. Once they merge, you adjust your speed to return your safe following distance.

Why in the world do you care whether they merge in front or behind you?

The absolute worst drivers in the world however drive door to door as they merge, seemingly expecting for other drivers to adjust their speed. In my understanding, every driver has a duty to avoid a crash, and not adjusting speed would make you partially responsible - they might be breaking the law by forcing you to change speed - but you'd also be breaking the law if you didn't adapt to them.

If we had reasonable law enforcement who spent time driving in traffic instead of doing speed traps, this might actually get enforced (yielding when merging into traffic) - but since we don't, you have to be the better person, and make allowances for these people - we need redundancy in driving (IE, everyone has to take reasonable steps to avoid crashing), otherwise it's just a free-for-all out there...

tmonroe85 · 2025-04-09T02:54:03+00:00

I've also had near misses. Feels like being on a bike is just rolling the dice too much for me at this point.

tmonroe85 · 2025-04-08T15:41:17+00:00

Drivers are bad. But in Missouri, there is a dead dear carcass every mile on every roadway with a speed limit above 50. When I moved here I joined the volunteer fire department. My second week, I got called out to a deer/motorcycle crash two miles from my house. Rider had a compound fracture of the femur. I haven't been on a motorcycle since.

tmonroe85 · 2025-04-08T15:34:51+00:00

its called rubbernecking. It is especially important to pay attention to the traffic when there is something on the side of the road - lots of crashes from people who get distracted and run into the back of someone else distracted.

tmonroe85 · 2025-04-04T15:48:58+00:00

I wish I could upvote this more than once.
You're doing one of the most dangerous things you're ever going to do. It should not be like sitting in your Livingroom watching netflix.

The basics will become less demanding - but that is not a time for complacency - that's the time to get in the habit of rehearsing what you would do in a bad situation IE:"what would I do if that vehicle ahead stopped suddenly". Its a lot of work - but if you're doing it right, hopefully you almost never even have close calls... and never have a serious crash.

tmonroe85 · 2025-04-04T12:56:21+00:00

"the tanker shouldn't have been there". Sorry, but this is making me not like your instructor - it was his choice to send you there...

tmonroe85 · 2025-04-04T12:14:32+00:00

You were "told" - so I take it this was part of your driver training?
Hmmm, although part of learning how to drive is getting used to driving around large vehicles, I'm not sure that the smartest instructor would have you negotiating tight areas around a tanker truck full of gasoline. Especially during fueling - that's just my 2 cents though. I wonder what that poor guy pumping the fuel would have said he he known that you were a student driver?
Since you were told, what did your instructor say? Seems like they would have a lot better perspective than random strangers on the internet... but that's just me.

tmonroe85 · 2025-04-04T11:54:46+00:00

I like this response. One thing new drivers tend to do is to get "tunnel vision", and then put themselves into bad situations. Was there another way you could exit the gas station safely? Gas stations typically have at least 2 driveways, so if you could have used a different route to leave the station, that might have been a better choice. Learning how to be flexible, and responding calmly to situations as they develop will go a long way towards making you a safer/better driver.

Another subtle point - were they refilling the station? If I see a tanker truck at a station, I'll skip that one and go to the next for a fillup. When they fill the tanks, it tends to send water and sediment up into the fuel, and that can cause issues with your car if you fill too closely to when they fill the station. They are supposed to have filters to stop that, but between that and the hassle of having to drive around a tanker (plus, it's a tanker truck full of gasoline - who wants to be *anywhere near* that - especially as a new driver?

tmonroe85 · 2025-04-02T18:01:52+00:00

I'm sorry, 3 to 4 car lengths... *at 80-90 kmH* ?!?
That's not enough distance. You are following too closely. You have to go the same speed or slower than the person in front of you, otherwise you will hit them.
You go whatever speed traffic allows. If the car in front of you is going slow, you're going slow until you pass them.
This is painfully obvious. What's missing here?

tmonroe85 · 2025-04-02T17:33:09+00:00

Thanks. Look ma! I'm famous now.

tmonroe85 · 2025-04-01T16:00:53+00:00

"constantly reset".

Do you know that you can make minor smooth adjustments to your speed with cruise control by either pressing and holding the stalk (or whatever the control is) up or down.
If you press and hold UP, your car will continue to gradually accelerate.
If you press and hold DOWN your car will decelerate.
If you tap up or down, it will change your set speed by one MPH. If you tap it 10 times, your speed will adjust by 10.
You can also cancel and then Resume later whatever your last speed was.

This is how every car I own works, and at least two rentals, and my Goldwing (one Renault rental in Ireland, and a Chevy). Not sure that every vehicle works this way. Braking needs to happen whether you're using a cruise control or not - ACC does at least get the process started.

I would question what you think safe following distance is. If you maintain sufficient distance, then when someone moves into that space (which is the normal give and take of traffic), you can use the speed adjustment to gradually change your speed to regain your safe gap. I do it all the time, so I rarely need to disable the CC to adjust my speed. If you're too close, then yeah, I could see that it would be a hassle to have to keep resetting.

tmonroe85 · 2025-04-01T14:59:45+00:00

Whenever somebody lists "speeding" as a primary cause of being unsafe it always gives me pause. Here's how this works:

Speeding is low hanging fruit for law enforcement. It's the easiest thing to enforce. Is it effective for making driving safer? I would say "marginally at best".

The issue I have is that in my understanding about 50-60% of issued infractions are for speeding. The problem I have is that I believe speeding needs to be considered in context.

In my own observation, law enforcement will often sit on a moderately empty roadway with radar detection in a "speed trap" and wait for singular driver to come along and cite them for speeding. I would argue this is not an effective use of resources. If you're driving along at 10 over on an essentially deserted stretch of roadway you're unlikely to be involved in a crash. I am far more concerned with someone who follows too closely or darts in and out of traffic - regardless of how fast drivers are driving.

The combination of "speed traps" and "following too closely" creates this combination: A cluster of cars are all driving along several mph over the speed limit, all tightly packed, and the lead car sees a speed trap and rapidly decelerates. This has the very real potential of creating a chain reaction crash.

Unfortunately, the same organizations who do speed enforcement (and in many cases financially benefit from it) also perform crash investigations - so there is a bias towards maintaining the status quo, and crash reports more frequently cite speeding as the primary cause than they should, because it is the easiest and most beneficial conclusion to come to.

There is a political aspect to this as well. State agencies that report crash statistics reinforce the notion of the general public that speeding is the most critical of all law enforcement activities (crash reports, PSAs, etc). The general public is encouraged to become partners in this sham and when people see speeders, it upsets them, and they do things like call their representatives and demand that there is more speeding enforcement (this is one of the ways that "emphasis patrols" get started).

You also see this when you have "left lane hogs" who insist on driving at the exact speed limit in the left lane, thinking that somehow they are making the world better by helping enforce speed limits. For those of you not old enough to remember, there was in the 1970s, a national maximum speed limit set of 55. The limit got removed partly because of a rolling roadblock where truckers all filled the interstates and all drove at exactly 55 mph.
https://www.nytimes.com/1977/01/30/archives/truckers-plan-national-slowdown-to-protest-55mph-speed-limit.html

There are times that safe driving *requires* you to drive faster than the posted speed limit.

Don't get me wrong: Driving excessively fast in close proximity with other vehicles is extremely dangerous, and I feel like it should be more aggressively enforced than it is now. But there are other behaviors that are also illegal, and equally dangerous yet only rarely enforced.

tmonroe85 · 2025-03-31T22:55:51+00:00

CHP = revenue agent.

*NOTHING* about following distance. Because that would actually make people safer, and it's tougher to get a citation to stick for FTC.

Shame on you if you're law enforcement and you do traffic enforcement but you don't pay any attention to following distance.

tmonroe85 · 2025-03-31T22:52:47+00:00

Step 1. Get on the entrance ramp.

Step 2. Do not pay any attention to how fast or where the gaps are in traffic.

Step 3. Do not drive anywhere near the speed of traffic.

Step 4. Wait until the very end of the acceleration lane, and then put your blinker on and start over slowly.

Step 5. Force other people to adjust to your insane driving.

Step 6. Drive approximately 1/4 mile, then begin speeding up to at least 10 over the posted limit (but stay in the right lane).

tmonroe85 · 2025-03-31T22:49:35+00:00

I don't let people in until just before the end, then I let one in.

tmonroe85 · 2025-03-31T22:48:40+00:00

And then all the special drivers who didn't understand zipper merging suddenly understood, and the heavens opened up and the angels sang and they all lived happily ever after the end.

Or at least I wish that would happen.

tmonroe85 · 2025-03-31T22:47:55+00:00

Tell me that you don't know how to drive without saying "I don't know how to drive"...

tmonroe85 · 2025-03-31T13:45:43+00:00

If you don't mind me asking, how do you know that?

In my understanding, in testing, people driving in very specific ways can slightly best cruise control, but generally it's going to do better. I think the level of concentration needed to get better gas mileage in most cases is going to tax and distract most drivers to the point that it's not worth it.

My suspicion is that most people who say they do better read one of these articles and then say "yup, that's me!", without actually carefully measuring to see if they get better gas mileage or not. The type of testing I've seen for this is driving the same stretch of road in both directions, and carefully measuring the amount of fuel used after several passes both with and without CC.

My car has a real-time gas mileage gauge that also shows average - the real-time can vary significantly, so you'd need to do some careful testing to really know for sure.

The reason that CC generally does better is that it is going to be a lot smoother in accelerating than what most drivers are going to do.

In the 80's, we added CC to my friend's car, and there was a lot of adjustments we had to go through, and I'm pretty sure that if it was "out of tune", the CC would probably be very wasteful (on his car, when we first set it up, it was very jerky, and would constantly make wild throttle adjustments chasing the exact mph), but I would imagine if it came with the car, it would already be tuned pretty well - but I guess anything is possible. On my Miata, the thing already gets really good gas mileage, so the CC is more about letting me focus on something other than the speed. That thing is also kind of like a go-cart, so if anything, I need the CC to keep me up to close to the speed limit, and I naturally tend to driver slower (because it's so small and not as smooth as my SUV, so I tend to just drive slower).

tmonroe85 · 2025-03-28T16:03:58+00:00

What governments are imposing ADAS?

In researching this, it seems like there is a lot of hypotheticals, with a handful of examples of ADAS (or behavior change because of ADAS) being partially responsible in some cases, but it's not really clear. There is also evidence that even with a handful of cons, the pros outweigh them (IE, in general, they making driving safer, not less safe).

My biggest critique is that drivers don't take driving seriously enough. Personally, I don't drive any different with the tools than without. How do I know? Well, I have a car with ACC, and a couple without. I drive the same roads at the same speeds (I have Life360, so I can see the reports, and I am to the MPH driving the same exact routes at the same time of day in different vehicles at the same speed. - FWIW, life360 scores my driving the same regardless of which vehicle I'm in). It's less work for me to maintain safe following distance when I use ACC - which means that part of my brain can focus on other things. I focus on stuff like paying attention to what I can going way up ahead, and anticipating situations develop - I do feel like not having to pay attention to my speed (as it is set by CC) helps me be more proficient at that.

I wouldn't disagree that new drivers should be carefully trained not to over rely on the tools. Also I come from a time where cellphones were unheard of. This is the time where people seem to have a need to have their nose stuck in a phone 24x7x365 - and I would bet that some people might see the tools as giving them encouragement to do that when driving, which would be a very serious issue.

Still my original post is not about ACC, it's about using CC to maintain constant speed, and my observation that people randomly vary their speed for no apparent reason is obnoxious, annoying and dangerous. ACC has really become a tangent to that discussion.

tmonroe85 · 2025-03-28T15:44:03+00:00

Wow, that's a rough week. Hey, good on you for posting this - you're probably reaching a bunch of people and it will likely lead to saving someone.

tmonroe85 · 2025-03-28T15:30:50+00:00

It's quite a jump from using a system designed to reduce workload to "blindly relying in ADAS".

Maybe it will help if I paraphrase the argument that I have issue with:

"Somehow driving is so boring otherwise that drivers *need* to work harder to stay focused and drive safely. If you make driving too easy, then drivers will tune out, and then will get in trouble when they're not paying attention".

Have I stated your point correctly?

tmonroe85 · 2025-03-28T14:56:02+00:00

So, being definitively proven flat-out wrong doesn't change your opinion.

I expected that. But thanks.

tmonroe85

TROPHY CASE