Model X Crash on US-101 (Mountain View, CA)

[TEG]

There's a satellite view on google maps that shows it in the original condition. In addition, it looks like there used to be some plastic warning sticks in front of that, because of the series of dots; possible glue residue or bases still in place.
View attachment 288763

I don't think it ever had plastic "warning sticks" there.

Those marks before it were from the original (circa 2008-2011) barrier which was a series of wooden posts (gradually getting larger as you got closer to the wall.)
It appears that they removed the posts around 2012 and switched to barrels for a while, then replaced the barrels with the "Smart Cushion" type device. I gather they did that so that it is reusable now.

By removing that old / long / wooden post based crash cushion, and switching to a much shorter "smart cushion" device, they made that section look more like an actual lane, and gave people more room to "cut back across" at the last minute. I am sure many people have since driven over that section that used to have wooden posts there. The original designers intended that to be a barrier and a crash absorption area, not an empty lane.

Also, when the "smart cusion" has been left compressed there is even more area to drive across, and it starts to seem more and more like a lane there since the distance without a barrier has become even longer.

Here in Sep 2015 you can see grass growing out of those old post holes, and the "smart cushion" compressed, the warning label partially damaged, and no extra signs or pylons:

There were some warning pylons there in Jan 2015 back when the "smart cushion" was in the "ready" state:

Note, in the most recent pictures it looks like they have tried to clean up those post holes, sand them down / fill them in so you don't see much of them anymore.

Back in Jun 2017 they still had the metal post holders sticking up from the road:

But now they are sanded down and covered with goop:

 

[flar]

It was intact as of about 4:50 yesterday evening, so probably.

(yesterday there refers to the day before the accident)

I'm replying with this quote from dgatwood because dashcam footage from a week ago with the barrier collapsed has a lot of speculation that the barrier was not restored before yesterday's accident, so I'm hoping that dgatwood will clarify again to end the speculation...?

 

[flar]

I'm a bit concerned that there has been so much civic planning energy expended on redesigning the crash barrier to make it less annoying to highway maintenance when people invariably crash there rather than planning to reduce the chance of an accident. More changes to the barrier seem to have happened than remedies.

Cross-hatch paint
soft barrier "posts"
Improving signage
Fixing pavement lines

Painting the pavement may not seem like a lot, but it would definitely help visibility in bad weather and glare, and I'm pretty sure that people would statistically have more of an aversion to driving over an area with garish markings as compared to driving over a blank area "between lanes".

The posts may not prevent last minute lane changes, but they will force them sooner. And, I hate to admit it but, I get the sinking feeling that the danger of the soft barrier posts nicking someone's fender paint might prove more of a disincentive than relying on their ability to decide if they can "make the lane change" before hitting the crash barrier...?

I live in the area and used to drive that section quite a bit, but I haven't been through there enough lately to comment on how the signage might be improved.

I do know that there are many places in Bay Area roads where pavement lines are more visible than the lane markings even to a well seasoned driver (my pity on the neural nets trying to figure it out). I wish they'd take the issue more seriously as the roadways are expanded, but the only thing I've ever seen them do is to pour tar into the cracks which basically just makes them even more visible and thus even more of a conflict with the ever-disappearing lane markings.

 

[SMAlset]

They are talking about cylinder "A" here, not air suspension part "B":
View attachment 288766

I think it was a small SCUBA type tank. Seems plausible given the swim mask with the backpack.
View attachment 288768

Much better photo of the tank in that photo. I can see a label on it and very possible in that case the green item is a swim mask and the orange an attached snorkel. Probably all removed from the trunk before the tank could explode in the fire. Assuming this is correct it gives some personality to the driver or his family.

BTW thank you for digging up the barrier videos and history of images of that point in the roadway. Learned a lot from your posts. As we were watching the repair video (#161 post), we both were thinking how many steps were needed by a trained crew to set it properly. Also required a number of crew members to ensure it was done correctly between pulling it out and setting the pins and cables. Went on to watch the videos on the crash tests of this version barrier and wonder if they also did crash dummy assessments for level of injuries. You do get a good idea of the damage to vehicles however. I understand that Teslas are designed to dissipate the g force during collision and break apart more like race cars, but I really have to wonder if that barrier was never reset and he was essentially hitting a concrete wall head on. Even with all of the tests none of the vehicles flew in the air. The TMC member who posted one of his wife's co-workers had helped pull him out, said he was unconscious and had internal injuries. Assuming the barrier wasn't reset, have to question if the barrier was properly set, would his injuries have been survivable? There must be records on this. We have seen in the press many very bad head on type collisions in the Model X (thinking of a more recent one in Arizonia involving a wrongway driver) and that Tesla driver survived.

Given how heavily trafficked this area is, this barrier issue and lane design should be of concern to all of us living or traveling in this area. I wonder what the total number of accidents in this section have been over the years since it was redesigned. I assume we will be learning shortly who lost their life here. I also wonder if he is the only one to have died.

 

[TEG]

On another note, the fact that the "smart cushion" is shown in so many old photos to be fully compressed seems like it is an inadequate device for this location. In the test videos I posted before you see cars being stopped before the cushion fully compresses. Those were tests of vehicles doing ~60mph. It seems like this particular "smart cushion" isn't a version able to fully decelerate vehicles at the speeds they are going when they hit it. It seems to me like they really should have a longer area there based on past history. It looks like there is enough room there to have 2 of those smart cushion devices in line. Maybe it would make sense to put a second one where those old post holes were so that the one in back would only get hit in extreme cases like we saw yesterday.
I don't want to second guess the road planners / designers, but I don't think that thing is supposed to become fully compressed so frequently.

 

[TEG]

Also, I live near that area, and drive it frequently myself. Thus a reason why I am spending extra effort critiquing and understanding that barrier history.

 

[bxr140]

Cross-hatch paint
soft barrier "posts"
Improving signage
Fixing pavement lines

Signage is already self-evident. There are three overhead signs that are not confusing, starting over a half mile upstream. You can't fix stupid; you can't make someone pay attention more.

Bollards would certainly help, though one high speed run over would probably rip the lot of them out.

Cross hatching is probably a good addition in the wedge, but overall pavement lines are self evident. I think policy would need to change to make them more idiot proof. Here's the same kind of intersection in socal: Google Maps

 

[TEG]

On another note, this is very close to Google HQ, so there is an unusually large amount of old streetview photos available.

 

[mongo]

On another note, the fact that the "smart cushion" is shown in so many old photos to be fully compressed seems like it is an inadequate device for this location. In the test videos I posted before you see cars being stopped before the cushion fully compresses. Those were tests of vehicles doing ~60mph. It seems like this particular "smart cushion" isn't a version able to fully decelerate vehicles at the speeds they are going when they hit it. It seems to me like they really should have a longer area there based on past history. It looks like there is enough room there to have 2 of those smart cushion devices in line. Maybe it would make sense to put a second one where those old post holes were so that the one in back would only get hit in extreme cases like we saw yesterday.
I don't want to second guess the road planners / designers, but I don't think that thing is supposed to become fully compressed so frequently.

The piston energy absorber might be out of spec/ worn out.

 

[TEG]

...
Cross hatching is probably a good addition in the wedge, but overall pavement lines are self evident. I think policy would need to change to make them more idiot proof. Here's the same kind of intersection in socal: Google Maps

That one shows an entirely different sort of crash cushion:

One advantage of that kind, and the sand barrels is that people can notice more easily when it has been used up, and would contact CALTRANS asking for it to be replaced. With the "Smart Cusion" sled, I think people drive past a compressed one all day long without noticing that it needs to be reset.
Perhaps that is what was meant by "low maintenance" in one of the crash cushion comparison documents I posted before.

 

[SMAlset]

Interestingly just last month the 2018 Tesla X and the Volvo XC90 (vehicle used in Uber's self-driving tests) were awarded 5 star ratings from the National Highway Traffic Safety Administration in front and side crashes. The article I read this in stated that the 2017 version of the Model X also received a 5-star rating in rollovers. https://www.cars.com/articles/5-sta...vo-xc90-earn-top-crash-ratings-1420699236803/ Makes you wonder how other cars and drivers/passengers would do when impacting this barrier area.

 

[McRat]

They need one of these (FF to 1:25):

 

[TEG]

Also, by the way, in this photo from the video here:
Crash involving Tesla on Hwy 101 in Mountain View
You can see a bunch of Model X front end components (I think perhaps gear box, half shafts, etc) jammed up against the "smart cushion":

I wonder if the "smart cushion" is so narrow that the Model X crash beams straddle either side and so it may have "punched a hole right in the middle" of the X crash structure?

I think those barrier tests tend to have a wider obstacle that hits the crumple structures closer to the tires.

 

[RedOctober]

Oh wow, look at this one:

View attachment 288779

Hope these workers had crash prevention trucks behind them. From the photo this looks pretty dangerous. Really appreciall the info you have provided. Now if you find one of the days leading up to the crash showing it was not reset that will be very interesting because from the videos you have provided the drivers most likely would have lived.

 

[TEG]

Much better photo of the tank in that photo. I can see a label on it and very possible in that case the green item is a swim mask and the orange an attached snorkel. Probably all removed from the trunk before the tank could explode in the fire.

I am starting to rethink the idea that it could be a small SCUBA tank.
In this photo:

I think I can make out a Tesla logo in the lower left. Perhaps it is part of the air suspension: a tank to store the compressed air that can feed the air pistons at each wheel.

Probably one of these:
2016-2017 TESLA MODEL X 9 LITRE AIR SUSPENSION RESERVOIR TANK 1027921-00-B | eBay


Some of us made the wrong conclusion that it might be a SCUBA tank based on seeing a swim mask next to it.

 

[SMAlset]

So we were a while back in this thread also discussing the possibility of retrieving any info from the car given it's state and fire damage. Think the assumption was nill. I was wondering though after reading about Tesla's recent EDR Retrival Hardware Kit whether it might still be possible in this situation. The reason I ask is because there are apparently 2 methods of accessing and retrieving recorded data from the RCM, one of them being Direct-to-module retrieval. According to the Crash Data Group (who sells the kit), "In the Model X and the Model 3, the vehicle's RCM is located on the floor of the passenger compartment under the center console and between the seats. In the Model S, the vehicle's RCM is located on the floor of the passenger compartment, under the center screen." Since it appears only the very front battery pack was affected by fire which did spread throughout the interior cabin, I'm still left wondering if the RCM might have been protected underneath there.

Tesla EDR Kit - Crash Data Group

 

[ddkilzer]

On another note, the fact that the "smart cushion" is shown in so many old photos to be fully compressed seems like it is an inadequate device for this location. In the test videos I posted before you see cars being stopped before the cushion fully compresses. Those were tests of vehicles doing ~60mph. It seems like this particular "smart cushion" isn't a version able to fully decelerate vehicles at the speeds they are going when they hit it. It seems to me like they really should have a longer area there based on past history. It looks like there is enough room there to have 2 of those smart cushion devices in line. Maybe it would make sense to put a second one where those old post holes were so that the one in back would only get hit in extreme cases like we saw yesterday.
I don't want to second guess the road planners / designers, but I don't think that thing is supposed to become fully compressed so frequently.

A Model S/X would require more energy dissipation to stop at the same speed due to the extra weight of the vehicle (batteries). One has to wonder if these barriers are designed for heavier vehicles, or how they perform (even when properly reset) when a heavier vehicle hits them.

Regarding the vehicle "flipping" in some reports, does anyone think it rolled in the air and landed on its tires? I wonder if only the rear end of the vehicle "flipped up" in the air after its forward motion stopped after hitting the barrier (whether or not it was reset properly), and then landed once again on the pavement.

We also haven't heard how the other two vehicles where involved in the accident. Did they hit the Model X directly (and cause more damage)? Did the third vehicle hit the second vehicle or the Model X? May have to wait for a more detailed report from the CHP (which I assume will be coming).

I'm also interested in the root cause(s) here since I live in the area and own a Model X. I bought it, in part, for Tesla's history of safety design to protect my family (the five-star rating wasn't available when I bought it). I'm really curious what can be learned from this accident to improve vehicle safety in the future (and what not to do as a driver in a similar situation).

 

[SMAlset]

I am starting to rethink the idea that it could be a small SCUBA tank.
In this photo:
View attachment 288863
I think I can make out a Tesla logo in the lower left. Perhaps it is part of the air suspension, but a tank to store the compressed air.

Probably one of these:
2016-2017 TESLA MODEL X 9 LITRE AIR SUSPENSION RESERVOIR TANK 1027921-00-B | eBay
View attachment 288864

Some of us made the wrong conclusion based on seeing the swim mask next to it.

You know seeing a photo of that part I do think your right. I did find silver dive tanks online however so that was a good guess given the limited photos and quality of them we have to examine. And yes your skill at blowing up and maybe improving the image on that label is very good. The Tesla T logo at the very bottom does seem to be there. I have no idea about what this part does or where it would be located. Assume in the front under hood section, since that all seemed to have been scattered widely.

 

[dgatwood]

(yesterday there refers to the day before the accident)

I'm replying with this quote from dgatwood because dashcam footage from a week ago with the barrier collapsed has a lot of speculation that the barrier was not restored before yesterday's accident, so I'm hoping that dgatwood will clarify again to end the speculation...?

I drove that road on Thursday night, and I'm about 99% sure the barrier had been reset. I vaguely recall noticing the barrier. It is possible that I'm remembering wrong, though, and it is also possible that there could have been two crashes there within a few hours of each other.

Painting the pavement may not seem like a lot, but it would definitely help visibility in bad weather and glare, and I'm pretty sure that people would statistically have more of an aversion to driving over an area with garish markings as compared to driving over a blank area "between lanes".

The posts may not prevent last minute lane changes, but they will force them sooner. And, I hate to admit it but, I get the sinking feeling that the danger of the soft barrier posts nicking someone's fender paint might prove more of a disincentive than relying on their ability to decide if they can "make the lane change" before hitting the crash barrier...?

Strongly agreed—particularly regarding the addition of those plastic posts. Also, the fact that we're debating whether it was reset or not tells me that there needs to be a policy change. If it can't be reset immediately, they should have to put in temporary barrels before they reopen either carpool lane, and this should be mandated by law, or else it won't happen.

But the biggest thing that they can do to improve things is to make the signage better. The second sign about the exit is way past the point where it is too late to act on it. The second set of signs should be at least good fifty to a hundred feet earlier, possibly even as far back as the Shoreline bridge (which is just past where the first set of signs are. That also means that the first set should be even further back than they are.

And a third of the way from Rengstorff to Shoreline, that sign on the right side that says "Junction 85 1/2 mile" should also appear on the left.

The first hint that the left lane is an exit lane doesn't happen until you get to the signs on the Old Middlefield Rd. bridge right before Shoreline, just 3,000 feet from the hard gore point, and 2,000 feet from the start of the solid white line, which appears very suddenly right after you get out from under the Shoreline bridge. The fact that the line is partially obscured by the shadow of the bridge doesn't help. That solid line should really start before the Shoreline bridge so that it is more visible.

Also, there should be brightly colored pavement markings indicating that the left lane is an exit lane, starting just south of Oregon Expressway where the second carpool lane first appears, so that drivers are not caught off guard. I thought they had some white pavement paint, but I don't see it on Street View, so perhaps I'm remembering wrong. Either way, I guarantee if you had a green state route shield painted on the lane with a number painted on it, that would be a thousand times more visible. And the way I see it, they should appear as often as the carpool lane signs. After all, if you have to have those every couple of hundred feet to keep people from accidentally straying into the wrong lane, the routing markers seem like they should be at least as important.

 

[FlatSix911]

I am starting to rethink the idea that it could be a small SCUBA tank.
In this photo:
View attachment 288863
I think I can make out a Tesla logo in the lower left. Perhaps it is part of the air suspension, but a tank to store the compressed air.
Probably one of these:
2016-2017 TESLA MODEL X 9 LITRE AIR SUSPENSION RESERVOIR TANK 1027921-00-B | eBay
View attachment 288864

Some of us made the wrong conclusion based on seeing the swim mask next to it.

Correct, that cylinder is the compressed air storage tank for the air suspension.



Caltrans could be in big legal trouble if their compression sled was previously damaged and not repaired in a timely manner.