Safe Speed Forums

Four dead after hitting tree:

http://www.thesun.co.uk/sol/homepage/news/2543261/Four-killed-as-car-hits-tree.html

look at the tyres!

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Speed limit sign radio interview. TV Snap Unhappy
“It has never been the rule in this country – I hope it never will be - that suspected criminal offences must automatically be the subject of prosecution” He added that there should be a prosecution: “wherever it appears that the offence or the circumstances of its commission is or are of such a character that a prosecution in respect thereof is required in the public interest”
This approach has been endorsed by Attorney General ever since 1951. CPS Code

The picture quality isn't great, but the tread depth looks OK.

I know it is a very bad idea to mix tyres on an axle, but would it have significantly contributed to the accident. I would suggest that if one is driving to the point where it becomes a contributory factor, then the manner of driving itself was dangerous - ie on the ragged edge of the capabilities of the car.

The tread on the rhd tyre looks a bit odd, there looks to be a lot of wear between the right edge tread and the centre diagonal section, over inflation possibly?

If that is the case then while as Odin says that would not have caused the crash it does provide an indicator for the skills and mentality of the driver. I saw, or initially heard, a car on Friday that obviously had a mechanical fault of some kind, it was moving along making a metal on metal scraping sound. I was on foot and it pulled into the side road I was walking into and stopped on the rhs just in front of me, the driver braked moderately hard and the rear driverside wheel locked. He was getting out of the car as I walked past so I mentioned that the nasty sound was his brakes and he might want to get them checked, he did not seem that interested though at least there was no swearing in his response.

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Driving fast is for a particular time and place, I can do it I just only do it occasionally because I am a gentleman.
- James May

I wonder if it was an oversize tyre fitted to the wrong rim.

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Speed limit sign radio interview. TV Snap Unhappy
“It has never been the rule in this country – I hope it never will be - that suspected criminal offences must automatically be the subject of prosecution” He added that there should be a prosecution: “wherever it appears that the offence or the circumstances of its commission is or are of such a character that a prosecution in respect thereof is required in the public interest”
This approach has been endorsed by Attorney General ever since 1951. CPS Code

According to the report, the driver "skidded off a wet road".
As Anton rightly pointed out, that right tyre looks very wrong. The lack of a tread pattern (there is only 1 ridge, as opposed to 4 on the other tyre) could have resulted with an aquaplane and loss of control.

However, there is also talk the car hit a pothole, which is difficult to see on a dark, wet road. This may yet be a case of a neglected road surface (which will no doubt be cured with use of a camera [even when they fix the road surface]).

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Views expressed are personal opinions and are not necessarily shared by the Safe Speed campaign

I have blown up the picture, and the wear on the RH tyre is significant about 1/3 across the tread.
Also, the RH tyre looks narrower than the LH one. I don't think I can post it here due to copyright?

There is no significant impact damage to the front of the bonnet and cross member, or the front axles so presumably the vehicle hit the tree sideways on?
We had an earlier discussion on just such an accident started I think by Cam.Op in another thread somewhere.

I would guess - and perhaps somebody like Mole could confirm, that the car would be weaker, with more damage to the passenger compartment in such an impact than a head on impact... hence the fatal results? Certainly in the Plumpton crash in Cumbria, where a Prius struck an Escort as it crossed it's path, the passenger compartment was significantly damaged, being reduced by more than 50%, killing 5 occupants, despite the neither the Prius or Escort drivers driving beyond the speed limit.



I suspect that this latest tragedy will have resulted from an inexperienced driver, in a small car, failing to take into account the effect of four adults can have on the handling of the vehicle and exacerbated by poor maintenance of the tyres.
A sad loss to their families, which might perhaps of been avoided if better training was given to drivers in their early months of driving, especially with regard to changes in handling under load.

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Time to take responsibility for our actions.. and don't be afraid of speaking out!

comparing tread patterns is a bit of a red herring here isnt it as they are quite clearly completely different tyres.

the right hand tyre does have a fairly large flat section on, but in my limited experience, tread patterns with diagonal grooves do seem to have more solid rubber areas than the more regular block pattern seen on the left hand tyre.

BBC North West Tonight were pointing the finger at a pot -hole in the side of the road leading up to the crash site, the county council have now filled it in, but plod wouldn't speculate further than saying said pot-hole could be a contributory factor.

I think what is concerning some, is the wear, which seems to show the outer groove is worn away.
The tyre above which is SIMILAR has distinct grooves on both sides of the diagonal blocks, where as the tyre shown on the vehicle has only the inside grooves intact.
Tyres Online says of the Avon shown above:

It is the lack of outer tread which MIGHT lead to over confident cornering and loss of traction. It might also be on the wheel the wrong way round if it is a copy of the Avon

_________________
Time to take responsibility for our actions.. and don't be afraid of speaking out!

Disturbingly, I have had experience of tyre fittesr making fundamental errors. Once I had tyres fitted with the wrong rotation. And on one car I owned, that had wider tyres at the rear than the front, they fitted the rear size on all 4 corners, once even had a tyre the wrong profile fitted on one front wheel once. Now because I always examine work done to my vehicles I picked these up, and made them rectify the errors. I wonder how many people just trust that the work was done in a satisfactory manner?

Side impacts are difficult to protect people from the effects of because you're stuck (if you'll excuse the unfortunate choice of terminology!) between a rock and a hard place! Ideally, you'd like a big crumple zone to absorb as much energy as possible before the occupants come to rest. Unfortunately, you don't have that luxury when it comes to lateral protection. Because of the lack of space, you need to build the car good and stiff so that you minimise intrusion into the cabin space. That makes occupant decelerations higher. Also, blows to the side of the head seem to be more damaging to humans than blows to the front (not sure why)! The manufacturer has to get the best compromise he can between a compact shape, good energy absorption, minimal intrusion when impacted from the side, and low occupant decelerations. The current generation of cars with curtain airbags have made (I think) a big improvement here - close to having your cake and eating it, but still not as good as frontal impact protection.

Obviously the precise injury mechanism is difficult to speculate on - they might not have been belted in and if not, in a rollover situation, an airbag (even if fitted) wouldn't necessarily protect the bit of you that it expected to.

I don't think there's anything obviously wrong with the tyre on the right of the photo - it just looks like a typical asymmetric tread to me. I agree that it's not good practice to mix tyre brands (never mind types and tread patterns) on one axle, but surprisingly, not illegal. I think (hopefully Ed will chip in at this point!) the theory is that they work best on cars with a fair bit of neagtive camber. Most of the running is done on the bit with the big grooves so they clear the water well in the wet. When cornering hard, the outside wheel goes more vertical as the car rolls on its suspension so that more of the footprint is in contact with the tarmac. The theory (I think!) is that in the wet, you can't generate such big lateral forces so you never get enough body roll to get to the point where the "bald" bit is doing a lot of work. Obviously, if you're pushing the extremes, then I think tyre choice can be very important and it always suprises me that there isn't more legislation (a) to ban crappy "non-name" tyre imports that have lousy wet grip and (b) to impose tougher constraints on what owners are allowed to fit to a particular vehicle. Still, I guess that as long as everyone stays withn the speed limit that won't ever be a problem! (well, if not, I'm sure it's just a question of lowering all the speed limits some more)!

Do you not think the block treads on the outside look more worn than the inside?

The description of the similar Avon tread would seem to indicate the larger blocks belong on the outside, not the slightly smaller ones as here.
Pic. from Daily Express:

When you zoom in, the groove on the right appears smooth, unlike the two grooves on the left.
Does the right tyre look narrower than the one on the left?

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Time to take responsibility for our actions.. and don't be afraid of speaking out!

Hard to say to be honest. On both counts. I don't THINK the outside is excessively worn (i.e. on the limit) but it's not such a big photo and my eyesight isn't what it used to be...

Also not sure about the width. It certainly LOOKS a bit narrower but I don't know that it's not something to do with perspective or a trick of the light. Also, it's surprising just how much the same "nominal" width of tyre can vary from one manufacturer to the next. We ran into problems with snow chains once for exactly that reason!

The unusual tire wear, by my guess, is most likely due to either badly maintained alignment specs, shock dampers in need of replacement, or both.
Just a guess.

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The Rules for ALL ROAD USERS:
1) No one gets hurt
2) Nothing gets hit, except to protect others; see Rule#1
3) The Laws of Physics are invincible and immutable - so-called 'laws' of men are not
4) You are always immediately and ultimately responsible for your safety first, then proximately responsible for everyone's
Do not let other road users' mistakes become yours, nor yours become others
5) The rest, including laws of the land, is thoughtful observation, prescience, etiquette, decorum, and cooperation