Alt text:
This PSA brought to you by several would-be assassins who tried to wave me in front of speeding cars in the last month and who will have to try harder next time.
this post was submitted on 14 May 2024
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I used to have a job where I drove a box truck. It was slow empty and painfully slow full. It was also speed limited to 75mph. So I would tend to hang out with the semis on the hwy. One time I was driving down the hwy and this guy in a pretty new Volvo( so the fast ones) was coming down the on ramp. I could see he was going to merge right in front of me so I slowed down to give him some space. I figured he would want to be in front of the slow box truck. As he got close to the merge he slowed down so he was even with me. I gave him a little more space to merge in front of me and slowed down again. He had plenty of room left in the on merge lane if just used the skinny pedal. Instead he waited until was almost out of room then started honking at me. I did my best to speed up my painfully slow box truck but I am sure he has to slow down to the point he was merging at 45mph as everyone was doing 75-80mph. I am sure he was cursing me too because he wasn't willing to get up to hwy speed before merging.
I was taught it was the responsibility of the car getting on the highway to match the speed of the cars on the highway. If you’re already on the highway, keep a constant speed so the people getting on can match you. So he kept having to slow down because you were also slowing down. Just like the assassin pretending to be nice in the diagram, I think you were technically in the wrong here.
He never got up to hwy speed if he had he would have easily merged in front of me. I only slowed down by 5 to 10 mph.
Right, but its not your responsibility to slow down at all. Its kind of you to do so when the merging vehicle picks up on your intention, but when they don't, it makes a miscommunication like you describe.
Basically, i'd just describe it as being predictable. And bending the rules (even to be kind) is not predictable, usually.
I have a question on this. Let's assume everyone is a perfect driver and must have at least a 2 second following distance at all times. If there's a free flowing queue of traffic on the highway with 2-4 second gaps between, merging in is impossible without someone slowing down and letting you in. Every time I merge this situation stresses me out.
Merge into the gap, then slow down slightly to extend the space in front of you, and let the guy behind you slow down to extend the space in front of him. It’s not complicated
At 100 km/h (low-end highway spreed), or 1,666 m/minute, or 27.7 m per second, a 2 second gap leaves approximately 56.6 m (185.6 feet) between cars. With the average car length being ~4.9 m (~16 feet), even the absolute worst driver can merge in a space ten times the size of the average car, assuming they're matching highway speed.
Most people have no actual concept of how long 2 seconds actually is or how much space it would leave in reality.
Yeah, obviously you "can" merge, but in doing so you insert yourself into the middle of a 2 second gap creating 2 × less than 1 second gaps. Like I said, in this hypothetical everyone is a perfect driver that always follows the rules, so that's not an option.
For that matter, the driver behind should see that you are about to merge into a gap that's too small and slow down to leave a space that's at least 4 seconds big.
I'd also like to point out that your attitude to driving is terrible, the size in meters of anything on a highway is irrelevant, 2 seconds is not a lot of time to react and slow down a car at 100, and that just because you "can" do something doesn't mean you should.
People who haven't learned the physics of large trucks spend a surprising portion of their driving time competing for Darwin awards.
I want to will this not to be a problem anymore, but still see it all the time. I'm thankful that I've seen a lot of truckers react in surprisingly aware ways that save lives.
But every time I see it, I can't help but think that driver's luck isn't too likely to hold through too many more times making that move.