njkayaker

Do you really need to go the ad-homimen route. For a typo?

If you read the thread, it was used earlier and in the post I was replying to.

There was a hill and bushes obscuring the view.

From the cyclist's perspective, the car was approaching from slightly behind. And there was a hill and bushes obscuring the view.

The "constant bearing" stuff can't be used in the vast majority of intersections that cyclists deal with.

FBinNY 

More by way of a friendly nose tweak.

Used as intro to my real point.

genec

Google view of the offending intersection... showing that indeed one can see the cross road "at a much shorter distance," and thus should NOT just blast through the intersection, and that a driver looking off of center just a few degrees should be able to observe cross traffic.

https://www.google.co.uk/maps/@50.86...7i13312!8i6656

njkayaker

Yes. I said this (more or less) earlier.

The issue wasn't really the "constant bearing" stuff. It was a failure of dealing with the yield properly.

njkayaker

Is dyslexia really something to make light of?

You didn't pay attention to post I was replying to that didn't explain it and used the same spelling.

FBinNY 

Having lived with it for a lifetime, going back to before it was a recognized thing, I'm very comfortable making light of it in many contexts.

njkayaker

The article spells out the term.

genec

Due to not observing cross traffic, and then assuming "king of the road" attitude.

CliffordK

Keep in mind that the cyclist had the legal right of way. The drivers would have had the yield signs.

Freeway merges are common where one sees a car merging slightly ahead of oneself, and lets off the gas a bit to let them get ahead. Or slams on the gas to get past them.

I have also approached stopsigns, and perhaps slowed slightly to allow traffic to clear. It is all pretty common. Actually, going clipless, I can go mighty slow.

This, however, is a bit odd because the cyclist had the legal right-of-way, and the driver had the legal yield, so one would expect them to stop. But, if the cyclist had seen the car, then yes, coast for a couple of pedal strokes and let the car blow past. Of course, then one can have both the driver and cyclists adjust speed, but that confirms that they've seen each other.

That may be part of it, when approaching an intersection at an acute angle, with a car coming up faster, it may generally be unseen.

Although, this was pretty close to a right angle, so the car should have been visible, but the cyclist would still have had to look. I wonder if one's natural gaze is out to 90°, and the car was always behind that point.

37 MPH in the one case is only moderate speed. We've got a lot of roads where drivers will be over 50 MPH.

genec

Two great examples of where people who pay attention do use the CBDR technique, without thinking about what it really is... The freeway on ramp and merging is a perfect example of how DRIVERS DO do this... in spite of some folks thinking that "CRBD doesn't seem to really come into play driving anyway."

Of course we've all seen the driver that doesn't do this... the clown that comes right to the end of the merge ramp and then stops... because they did not "calculate" the merge.

FBinNY 

Let's be clear.

While the cyclists involved had the right of way, and the drivers are legally responsible for their deaths and injuries, there is still some degree of complicity by the cyclists themselves.

Yes, they were killed by a negligent driver, but they were also killed by false assumptions on their own part.

Either they assumed nothing was coming on the crossing road, or they assumed that the timing was OK, or they assumed that the driver would see them or heed the yield sign and slow or stop.

I'm not an advocate of slowing at every intersection, and don't do so. However, I am an advocate of maintaining situational awareness at all times, accounting for the vehicles around you, assuming nothing, and being ready to respond to their lapses.

Had those cyclists looked down the road and considered the possibilities, odds are they'd still be with us.

CliffordK

Exactly,

Although, the driver was likely always behind 90° with respect to the rider. So, while the cyclist may have been in the driver's pillar blind spot, the driver would have also required the cyclist to actually look, rather than just gaze in that direction.

So, it isn't just looking ahead, but also turning the head to follow the upcoming road, looking to the side and behind.

njkayaker

It's a key part of the thesis of the article. Some people missed that. It's fine to question it.

The key thesis of the article is that the collision was unavoidable. Because the cyclist and the driver were not able to see.

It was a "perfect storm" of sorts due to a combination of factors that just "works right" to produce an unavoidable collision.

You don't have to agree with that thesis but you have to understand that that is the thesis.

One's natural gaze is to the front (0 degrees). The cyclist and the driver were likely looking straight ahead (until they got to the intersection). Peripheral vision doesn't go out as far as 90 degrees. One has to move their head around. Something vectoring in at 90 or more degrees is going to be hard to notice.

It seems that both parties might not have been aware of the intersection until they were fairly close.

The article wasn't saying it wasn't moderate. It was saying that it just happens to be the right speed to contribute to the problem.

njkayaker

The failure came before "not observing cross traffic".

When I'm approaching a yield, I typically slow down and prepare to brake before being able to see traffic.

(Note that we can't know exactly what happened.)

It's two different approaches to deal with the same problem.

Drivers are estimating relative speed at close range. Drivers aren't thinking of bearing really at all.

The point of CBDR is that it works at very far ranges where estimating relative speed is difficult. The only thing you need to keep track of is relative bearing. The point of CBDR is to carefully monitor bearing (something I don't think drivers actually do; they carefully monitor relative speed).

The other important (and obvious difference) is that vessels tend to be hard to maneuver. You have to use CBDR to be able to start reacting well in-advance of getting anywhere near having a collision.

There are very few intersections that have sufficient view for the range the using CBDR could even be used.

In any case, the thesis of the article is that CBDR could not have been used in this situation at all. It isn't recommending using CBDR.

The solution recommended by the article is to force the cross traffic to stop.

njkayaker

Drive (ride) defensively.

The article isn't saying not to do that.

It's describing a situation where a bunch of factors combine to make a particular intersection especially hazardous.

The fact that drivers/riders should drive defensively doesn't mean the intersection can't be improved.

FBinNY 

Yes to all points.

However, focusing entirely on the problem of design and bad drivers, without speaking to what cyclists can do, is a disservice to cyclists, who need constructive help more than explanations of other people's failures.

If writing for cyclists, (as we do here) speak to cyclists, and what THEY can do to help themselves.

njkayaker

I wish people added "and be sure to drive/ride defensively" in their heads to any discussions.

I don't have a problem with people also mentioning things cyclists can improve their chances.

The article is kind of technical and some people (not necessarily you) are not quite getting what it's saying. (Understanding what it's saying doesn't mean people have to agree with it.)

FBinNY 

Again we agree.

However, "and be sure to drive/ride defensively" is a platitude. It's right up there with always wear your helmet, obey traffic laws, and don't try this at home. Folks don't need platitudes or slogans. They need positive, constructive help to learn to recognize and compensate for various "pre-accident" conditions like the one described in the article.

The forum is called Advocacy and Safety. There are those who focus on advocacy, which is fine and good. However, I prefer to focus on safety, and write to my audience, which is cyclists, not traffic engineers.

So I focus on describing the elements and what cyclists can do to take care of themselves (specifically), like understanding CBDR, which is something mostly unknown to those who've never been at the helm at sea,and which is why I early on referenced this article as required reading.

njkayaker

Yes, it's a platitude.

The idea is that people should always try to consider the defensive-driving issues even when it's not mentioned.

The CBDR thing really can't be used when driving/riding. It isn't necessary at all (people can manage intersections without it). One point of the article is that CBDR couldn't be used in this situation. Drivers use relative speed (not relative bearing) because the dynamics are different than piloting a vessel.

Bearing, in general, is a normal/common thing to keep track of (in a fairly precise way)(in a fairly precise way) on a vessel.

Having drivers keep track of bearing in a similar way is too much to ask and not very useful.

FBinNY 

I disagree. Understanding CBDR is useful to cyclists, as one more tool when when approaching an intersection with cross traffic. I'm not focused on what the driver can do, but what the cyclist can do.

In this specific intersection, the car is approaching from over the cyclist's shoulder, so it would take a bit of a head turn to spot it. But that head turn should be SOP when approaching an intersection, and once the car is noted, then the cyclist must track it, consider the implications, and prepare his options.

As I said in an earlier post, I generally don't slow in these situations, but I confirm that the car is slowing, and/or have my options planned in my mind.

genec

Uh, but we can, there was a "black box" in the second and third vehicles that killed cyclists. The box recorded a steady speed of 37mph all the way right through the intersection.

As far as CBDR... as discussed... drivers use it all the time to merge. They don't call it that, they may not understand all the parameters, but they use it none the less.

Indeed the stopping solution isn't bad... provided that locals actually stop... otherwise the better solution is to ensure that they cannot just "fly" through the intersection... with speed bumps, or road offset or roundabout.

Rollfast

Are you a pedestrian? I wouldn't trust that thing with a nuclear secret.

Rollfast

What I've been saying for years now and always getting ignored and ridiculed about it.

Watch yourself as well as them. Ignorance is pain or death.

njkayaker

In the vast majority of intersections that cyclist come across, CBDR can't be used (there aren't sufficient sightlines). (It wasn't usable, according to the article, in the cases the article talks about.)

The methods that are used for all those other intersections can also be used in the rare cases where cyclist might be able to use CBDR (a concept that is obscure for people without boat handling experience).

(CBDR is an old concept. If it was practical for cyclists to know about it, it seems unlikely that LAB, etc. didn't figure that out years ago.)

Riding along, one might not realize that there's an intersection coming until one is rather close. The rider is probably paying much more attention to the potential of traffic overtaking on his right. I doubt that many experienced/careful cyclists are looking behind to the left to check that something is sneaking up from behind. Especially, after having seen what was there (cows, horses, and bushes).

It's possible that the cyclist didn't realize there was an intersection until he was very close to it.

njkayaker

We don't know that the pillar setup was the same.

No, they use relative speed. They don't need to consider changing angles at all.

Speed bumps would be relatively easy and cheap to add. The road offset or roundabout would be much more expensive.