A different type of thread for Crash Analysis: Lane Splitting

[Enchanter]

A different sort of thread for Crash Analysis:

Skip to the 1min mark.

youtu.be/-x1pib4NIko?t=60

Let's not focus or discuss legal fault here. Let's focus on what the motorcyclist could have done to avoid this.

 

[HeatXfer]

His speed really didn't seem excessive, until the Pontiac pulled into the lane. It seems he target fixated and made no strong effort to avoid the car. He was about 5 car-lengths back when he braked and it only took 2.5 secs to reach the car (30mph delta?) but I think if he were prepared for the typical unannounced lane change he could have avoided the collision or at least been able to reduced the damage. I can't imagine that beast turning quickly, but I thought there was enough time and room for a big swerve to the left.

 

[budman]

That is one of the most dangerous sort of situations in terms of fast lane speed and the speed of the #2 lane. Not as extreme as it can be. To that extent I think there was a potential for the rider to not be on "high alert" status. The vehicle that filmed it gave him all the room in the world and I think that made the rider more comfortable.

His reaction:
I also feel that the best way to avoid that situation was to steer around it. As soon as he applied the brakes that took away quite a bit of that ability and when he tried he was held back by the braking inertia.

Identifying the collision and the path to avoid was secondary to his braking effort. I don't think he target fixated per say. Once on the binders he lost his chance to get around the vehicle in his path.

The delta he passed the film crew was not too significant however the delta to the #2 lane was very significant.

Hard hit. Hope he is OK.

 

[Schnellbandit]

I think car drivers moving to the left shoulder as in this case gives the lane sharer a false sense of security. The might be a tendancy to hurry and get past the driver who tried to give courtesy and so the rider breezes past not moving to the left quickly after the pass.

Cars often merge into the car pool lanes instantly and without warning. What I saw was using more free space on the right side of the lane and then an attempt to stop within a distance not remotely possible given the speed involved.

A move to the left immediately after the pass might have given the rider more of a chance to head to the emerg lane instead of braking.

 

[NeilInPacifica]

Splitting Collision on 880

https://www.youtube.com/watch?v=-x1pib4NIko

 

[EastBayDave]

I think car drivers moving to the left shoulder as in this case gives the lane sharer a false sense of security. The might be a tendency to hurry and get past the driver who tried to give courtesy and so the rider breezes past not moving to the left quickly after the pass.

Cars often merge into the car pool lanes instantly and without warning. What I saw was using more free space on the right side of the lane and then an attempt to stop within a distance not remotely possible given the speed involved.

A move to the left immediately after the pass might have given the rider more of a chance to head to the emerg lane instead of braking.

Totally agree w/above. Showed the rider 1st not positioning himself after the pass, second the speed delta between lanes of stopped & moving cars was huge. I think riders speed was more like above the legal limit. Going that fast close to line of stopped traffic is just asking f/it. I wonder if HE got cited f/that?

We all know cagers would NEVER see him. Much less the speed of the insanely fast approaching rider...going 60+ miles an hour faster than the stopped cars.

Come'on folks. Wake up. So sorry to be blunt; but I don't like seeing people hurt; especially when all this could so easily been avoided. That poor guy not only creamed the car, but then the center divider, then did a belly flop/headfirst into the pavement w/o slowing much.

Then that big, HEAVY full dresser landed on him. Crunch. Ugh. Anyone know if he made it?? :cry

 

[DataDan]

The crash happened here (Google maps link) on southbound I-880. Via Climber's CAD archive, the rider suffered only minor injuries.

By my estimate [1], the camera vehicle was doing 65mph, the motorcycle 90, and traffic in the #2 maybe 5-10 near the crash.

Once the rider passed the camera vehicle and the Pontiac came into view, he had no chance of preventing a crash either by braking [2] or swerving [3]. So his last chance to avoid the crash came before he split past at 90.

What should he have done?

1. Know how lane-splitting crashes occur. Most commonly they happen when a car changes lanes across the corridor. All lane-splitters should commit this to memory and follow it as a fundamental principle.
   
   
2. His delta to lane #2 was at least 75mph. Insane. If it takes 2 seconds for a car to complete a lane change, the motorcycle was 200ft behind when the driver began his maneuver. The purpose of keeping speed differential down is to give drivers a reasonable chance to see the motorcycle and to give the rider a reasonable chance to avoid impact due to an incursion. It follows that the the delta applies to the slower of the two lanes.
   
   
3. He shouldn't have been splitting AT ALL between a 65mph lane and a 5mph lane because the delta will necessarily be excessive.
   
   
4. In a free-flowing lane next to a stop-and-go lane, he should have been occupying his own space, not splitting, positioned near the left edge of his lane. The full 12ft lane width of space cushion would give him extra time to overtake the intruding vehicle. As it was, with no space cushion, he was in the worst possible position to deal with an incursion from the right.

---------------------------------------------------
[1] This note will describe my speed estimates. If I got it wrong, I welcome a correction. To estimate speed, I measured distances in Google Earth and time with my Timex stopwatch. Camera vehicle speed calculated between HOV diamonds here (37.410336, -121.911325) and here (37.407641, -121.910490), average of 3 timings. Motorcycle speed calculated between lane line segments here (37.407570, -121.910480) and here (37.407177, -121.910400), also average of 3, but this estimate is shakier. Lane #2 estimate is basically a WAG of time to traverse a 14ft lane-line segment.

[2] When the motorcycle pulled even with the front of the camera vehicle, the eventual point of impact was 180ft ahead. From 90mph with ZERO reaction time, that would take an average of 1.5g deceleration. The best published motorcycle braking performance is about 1.0g.

[3] At 90mph, it takes about 1.4 seconds to cover the 180ft between the front of the camera vehicle and the eventual impact point. To swerve a full lane width (12ft) in that time would require an average lateral acceleration of 12ft/sec^2 with ZERO reaction time. I'm not certain of this, but since it takes time to initiate a turn on a motorcycle (countersteer plus leaning), I doubt this is remotely possible in the available time. And even if it were, the motorcycle would likely hit the center divider before it could straighten out.

 

[NeilInPacifica]

Maybe the only way to ride in the HOV lane when traffic is at a standstill in the other lanes is to stay way to the left and keep speed well within the legal limit. When I find myself in those situations I am WAY nervous about just this type of crazy lane change in front of me, even when in a cage. Rider should not have taken the invitation from the film crew.

 

[Enchanter]

The crash happened here (Google maps link) on southbound I-880. Via Climber's CAD archive, the rider suffered only minor injuries.

By my estimate [1], the camera vehicle was doing 65mph, the motorcycle 90, and traffic in the #2 maybe 5-10 near the crash.

Once the rider passed the camera vehicle and the Pontiac came into view, he had no chance of preventing a crash either by braking [2] or swerving [3]. So his last chance to avoid the crash came before he split past at 90.

What should he have done?

1. Know how lane-splitting crashes occur. Most commonly they happen when a car changes lanes across the corridor. All lane-splitters should commit this to memory and follow it as a fundamental principle.
   
   
2. His delta to lane #2 was at least 75mph. Insane. If it takes 2 seconds for a car to complete a lane change, the motorcycle was 200ft behind when the driver began his maneuver. The purpose of keeping speed differential down is to give drivers a reasonable chance to see the motorcycle and to give the rider a reasonable chance to avoid impact due to an incursion. It follows that the the delta applies to the slower of the two lanes.
   
   
3. He shouldn't have been splitting AT ALL between a 65mph lane and a 5mph lane because the delta will necessarily be excessive.
   
   
4. In a free-flowing lane next to a stop-and-go lane, he should have been occupying his own space, not splitting, positioned near the left edge of his lane. The full 12ft lane width of space cushion would give him extra time to overtake the intruding vehicle. As it was, with no space cushion, he was in the worst possible position to deal with an incursion from the right.

---------------------------------------------------
[1] This note will describe my speed estimates. If I got it wrong, I welcome a correction. To estimate speed, I measured distances in Google Earth and time with my Timex stopwatch. Camera vehicle speed calculated between HOV diamonds here (37.410336, -121.911325) and here (37.407641, -121.910490), average of 3 timings. Motorcycle speed calculated between lane line segments here (37.407570, -121.910480) and here (37.407177, -121.910400), also average of 3, but this estimate is shakier. Lane #2 estimate is basically a WAG of time to traverse a 14ft lane-line segment.

[2] When the motorcycle pulled even with the front of the camera vehicle, the eventual point of impact was 180ft ahead. From 90mph with ZERO reaction time, that would take an average of 1.5g deceleration. The best published motorcycle braking performance is about 1.0g.

[3] At 90mph, it takes about 1.4 seconds to cover the 180ft between the front of the camera vehicle and the eventual impact point. To swerve a full lane width (12ft) in that time would require an average lateral acceleration of 12ft/sec^2 with ZERO reaction time. I'm not certain of this, but since it takes time to initiate a turn on a motorcycle (countersteer plus leaning), I doubt this is remotely possible in the available time. And even if it were, the motorcycle would likely hit the center divider before it could straighten out.

Brilliant! I'm so glad you are a BARFer.

 

[barfer]

Look at rider's head. It's a case of target fixation. He had room and chance to go further left and be clear. He would have been in clear if he didn't had panniers. The pannier made first contact with the rear side panel of the car. The front and center part of bike were clear.
Because of target fixation he straightened and went right towards the driver's door.
He should have looked at how much clearing he has, how much room before he hit the center divider.

Focus on situation and available clear space.

 

[EastBayDave]

Brilliant! I'm so glad you are a BARFer.

I agree, that well thought out & LONG great detailed post was beyond best I've seen on BARF lately. It looked like a ton of work!

I can honestly say I've not seen anything posted so good recently.:wow

I'm so happy to hear he got away w/minor injuries. It looked a lot worse; especially when after he fell at speed, the dresser smacked him. Shew. That guy must'a been in hella good shape. Or young? Whoa!

WTG DataDan, awesome post! :thumbup :teeth

 

[RV6John]

Brilliant! I'm so glad you are a BARFer.

I agree also. I would have estimated the speeds much lower but DataDan's reasoning is sound.

All good observations on the speed differences and failure to avoid the car to the left.

With the amount of fork dive shown, he was hard on the brakes and at that point turning significantly was not an option. His only option would have been to trail off the brakes and turn the bike. That is if his reactions would have permitted this.

Two other points I noticed.

Was the van in back of the car a factor? Possibly blocking the view of the car from the biker and the biker from the car?

I wonder if the rider did not keep situational awareness with the camera vehicle and might have believed it was too close to move sharply left.

 

[Slabhappy]

I noticed 2 long skid marks moving left on the shoulder just before the collision point, it looks like this situation is repeated by cars merging abruptly often. Not something the rider would see but, worth noting for future reference at that location.
I have been baited by these "kind" drivers already at or above the speed limit moving over to let me split. I refuse and stay in the lane behind them.

 

[EastBayDave]

I have been baited by these "kind" drivers already at or above the speed limit moving over to let me split. I refuse and stay in the lane behind them.

If at/over the limit, I see no reason to split. Your not going to get far before either someone pulls into lane, or it slows....:x

 

[budman]

Brilliant Dan. :wow

90ish... holy sh!t. Does not seem that fast, but math is math.

I still feel I could have swerved around this on my bike, but I am an overconfident SOB. :teeth

 

[clutchslip]

I still feel I could have swerved around this on my bike, but I am an overconfident SOB. :teeth

And perhaps you could. Unfortunately, I don't think that odds are in favor of most people being able to avoid a collision under these circumstances. And unfortunately, you can see riders all the time who think they too can avoid splitting splats, despite outrageous deltas.

It appears that the video truck might not have been able to stop in time to avoid a collision with the lane changing auto, either. Thus the speeds were definitely exceeding any reasonable "safe zone".

I have been baited by these "kind" drivers already at or above the speed limit moving over to let me split. I refuse and stay in the lane behind them.

I have stated numerous times that I don't trust these drivers and never pass them in the same lane.

Unnecessary lane sharing at excessive speed seems like the simple reasons for the collision. Thus, don't split at high speeds and ridiculous deltas, even if you are the second coming of King Kenny Roberts.

 

[matjam]

...

Excellent analysis.

Stopped/barely moving cars next to a line moving at 50+ sets off massive alarms in my head when I'm splitting. I'll usually just stick to the left and sit a generous distance behind a cage and wait for the other lane to start moving again.

Sometimes when I've been a bit impatient, I've broken that rule and sometimes I've had a near miss because of it.

Impatience kills.

My commute from Concord to the city can be anywhere from 35 minutes with zero traffic to 50 minutes with heavy traffic. I might be able to shave off 5 minutes if I ride like an absolute lunatic ... but it's just not worth it.

 

[Outta Control]

Wow DD that was well done research and analysis.

:applause

 

[Pking]

I still believe even if the biker swerved and missed a collision, the recording vehicle would have slammed into the cutlass anyway. He/she simultaneously changed lanes and turn on the blinker at the same time.

 

[Enchanter]

Splitting at that speed, at that speed differential, and into a very large gap, was a high risk move. Sure the car driver (insert something here), but in the end, we all know that banking on the car driver(s) to do the correct/right thing, doesn't keep us from being injured.

We can debate this riders braking and swerving skills until we're blue in the face. The effort would be better spent on the mental aspects of this crash: judgment. That is the lesson that we can immediately apply on our next ride. Do we really need to split past when the surrounding traffic (or in this case the traffic in our lane) is already going at a fairly high speed? Do we really need to split past when the speed differential is great?

What is the chance that this motorcyclist (split) past in this manner (on this ride or previous rides)? It's very possible that this was a regular part of his riding. He may have done it without incident so frequently that he was lulled into a false sense of security.

We need to be more proactive when we ride and not place ourselves into unnecessarily higher risk situations. (see my signature)