Diesels

[Munroast]

I have a 12 yo van thats been written off twice, gets 60+ mpg and does every thing you need a vehicle to do - in fact its about 10 x more useful than the wifes all singing all dancing, state of the art electronic piece of crap, seriously modern vehicles are getting worse and worse

 

[Captain Nemesis]

Might be truer to say "...so that it suffers less damage from other cars in an accident, I'd have thought?

The point is that theres a given amount of kinetic energy to dissipate by deforming bodywork, altering the direction of vehicles etc.

Even ignoring the fact that theres more KE involved if one vehicle is made more massive, if vehicle A is going to suffer less damage, or be shunted off-line less violently, then the vehicle B has to be damaged more, or thrown about more violently. Ye cannae change the laws of physics.

Are you able to answer these questions?

1) If a big heavy vehicle collides with a car, is the damage it does to that car compared to what it would do if it was smaller and lighter and all other factors (speeds, angles, points of impact etc) were the same

a) more
b) the same
c) less​

?


2) If you and your family were travelling in a car, then with all other factors such as relative speeds, angles, crash-protective construction, active and passive passenger restraints etcetcetc the same, which would you least like to be crashed into by, and why?

a) A smaller and lighter vehicle than yours,
b) one about the same as yours,
c) one larger and more massive than yours​

?

 

[Captain Nemesis]

However, Mrs Avocet now drives Skoda Kodiaq. Bloody mahoosive monster which weighs 1862kg with just driver and a full tank of fuel! The reason, is because she's only just started driving again, 2-and-a-bit years after an accident that ended her career and has left her with a permanent (thought mercifully, relatively slight) mobility impairment.

What was the other car she hit/hit her?

 

[Bodgedbuild]

I was browsing EV's on Ebay and this little beauty caught my eye for £6500, unfortunately the 100km range and 84kph top speed would mean I could not really use it for my commute to work....

 

[Captain Nemesis]

https://www.autotrader.co.uk/car-details/202105092396444

 

[Avocet]

No, but people want.

Which is the whole point people should have the choice of what they drive not dictated to what they are allowed to drive.

And yet, surely we have moral obligations to our fellow man? Just as it is no longer acceptable to smoke in public places, it is likely to become necessary to prohibit certain vehicles that also emit known toxins in public spaces, I fear.

 

[Avocet]

I have a 12 yo van thats been written off twice, gets 60+ mpg and does every thing you need a vehicle to do - in fact its about 10 x more useful than the wifes all singing all dancing, state of the art electronic piece of crap, seriously modern vehicles are getting worse and worse

In some ways, perhaps, but they're (like-for-like) safer and more environmentally friendly. If we all drove round in 1970s and '80s cars, we'd have air quality like Delhi!

 

[Avocet]

The point is that theres a given amount of kinetic energy to dissipate by deforming bodywork, altering the direction of vehicles etc.

Even ignoring the fact that theres more KE involved if one vehicle is made more massive, if vehicle A is going to suffer less damage, or be shunted off-line less violently, then the vehicle B has to be damaged more, or thrown about more violently. Ye cannae change the laws of physics.

I'm not sure we're disagreeing about anything here?! You're over-simplifying things a bit, but assuming similar crumple characteristics, then yes, I agree. I don't think I've claimed otherwise?

Are you able to answer these questions?

1) If a big heavy vehicle collides with a car, is the damage it does to that car compared to what it would do if it was smaller and lighter and all other factors (speeds, angles, points of impact etc) were the same

a) more
b) the same
c) less​

?

Likely to be less, making the assumptions above.

2) If you and your family were travelling in a car, then with all other factors such as relative speeds, angles, crash-protective construction, active and passive passenger restraints etcetcetc the same, which would you least like to be crashed into by, and why?

a) A smaller and lighter vehicle than yours,
b) one about the same as yours,
c) one larger and more massive than yours​

?

c) I'm not sure we're disagreeing about anything here?!

However, as I mentioned earlier (and Mrs. Avocet's crash is a good example), you're over-simplifying things.[/QUOTE]

 

[Avocet]

What was the other car she hit/hit her?

A 1293kg (according to the accident investigation report) SEAT Ibiza! (Vs. a 1605 kg Trail).

This is why your position (whilst true from a "laws of physics" point of view), isn't necessarily valid in real life. It was a very small-overlap offset frontal (in crash test terms). By the law of Sod, the SEAT hit the right hand front corner, but missed the chassis longitudinal that should have absorbed the crash energy. Instead, it hit the front wheel and shoved it hard into the end of the footwell. Mrs A had her right foot planted on the brake pedal at the time, and her left foot on the clutch pedal. The clutch master cylinder (having gone "metal-to-metal", as it were), transmitted a big shock into her left foot, whereas the brake pedal obviously still had some "give" in it. The result was that her left calcaneum was broken (and they're notoriously difficult to heal). She had other injuries (broken ribs, sternum, punctured lung), but it's the foot that has ended up never really healing properly.

The Ibiza looked much worse, (indeed the firemen cut the roof off it to get the 2 lads out). The 17 year old (who was the passenger), was released the following morning - there was stuff-all wrong with him! The 21 year old driver broke both wrists and a few small bones at the base of his spine, but was basically OK after a couple of months. Obviously, these were fit and healthy young lads, and Mrs. Avocet is a 50-odd year old woman whose bones aren't the best.

But that's 2006 crashworthiness vs. 2015 crashworthiness for you!

Even the coppers and the accident investigators were telling Mrs. Avocet how lucky she was being in a big, heavy 4x4, and saying they knew which one they'd rather have been in!

 

[norseman]

I was browsing EV's on Ebay and this little beauty caught my eye for £6500, unfortunately the 100km range and 84kph top speed would mean I could not really use it for my commute to work....View attachment 236241

Beauty
Looks more like a b..... invalid carriage.

 

[Captain Nemesis]

A 1293kg (according to the accident investigation report) SEAT Ibiza! (Vs. a 1605 kg Trail).

And what if it had been a Range Rover at more than twice the weight of that Ibiza?

This is why your position (whilst true from a "laws of physics" point of view), isn't necessarily valid in real life. It was a very small-overlap offset frontal (in crash test terms). By the law of Sod, the SEAT hit the right hand front corner, but missed the chassis longitudinal that should have absorbed the crash energy. Instead, it hit the front wheel and shoved it hard into the end of the footwell.

That's why I kept talking about everything else remaining the same.

If 2606kg had hit the front corner like that, instead of 1293kg?

And if the only reason the driver was in a 2.6 tonne car was that he wanted to do as much as he could to ensure that his car came out on top of any encounter?

As I said, no, I dont think that people explicitly and cynically decide to make life more dangerous for other road users, and yes, the dynamics of accidents are complex and unpredictable.

But they believe that they are safer in a big heavy car.

They know that if they could choose theyd want any car that hits them to be as light as possible. And they know full well why.

So explicit and cynical or not, the inevitable flip side of the choosing a big heavy car "because it is safer in an accident" coin really is choosing to make anybody they collide with less safe.

 

[Avocet]

And what if it had been a Range Rover at more than twice the weight of that Ibiza?



That's why I kept talking about everything else remaining the same.

If 2606kg had hit the front corner like that, instead of 1293kg?

Indeed. But you seem to be wanting to skew reality to fit your position. It was a single track road. The Range Rover is wider than the Ibiza. Assuming it to have been positioned in exactly the same place as the Ibiza, the overlap would have been greater and the X-Trail's crash cans would have done their thing. So what you're really saying, is that suppose someone had magically increased the density of an Ibiza, so that it had the mass of a Range Rover but the dimensions and structure of an Ibiza, thereby allowing it to hit in precisely the same position at the same speed in the same direction, etc, then the outcome would have been worse?

I would, of course, have to agree with you! The trouble is, real life ain't like that.

And if the only reason the driver was in a 2.6 tonne car was that he wanted to do as much as he could to ensure that his car came out on top of any encounter?

As I said, no, I dont think that people explicitly and cynically decide to make life more dangerous for other road users, and yes, the dynamics of accidents are complex and unpredictable.

But they believe that they are safer in a big heavy car.

They know that if they could choose theyd want any car that hits them to be as light as possible. And they know full well why.

So... in your first assertion, you say that you don't think people consciously decide to make life more dangerous for other road users, and in your second, you say that they know full well why they'd want any car that hit them to be as light as possible?

I think the truth lies somewhere between the two. I think people (mostly) go and buy a Range Rover because they want a Range Rover. If safety was a primary consideration, they'd probably go for an XC90, or something that got the highest EuroNCAP score in that class. What's more, NOBODY would EVER buy a Caterham! And yet, of course, some people DO buy Caterhams (and indeed, motorbikes). I have a 30+ year old Italian car with no airbags, which I don't suppose would get many EuroNCAP stars. I also have a new company car, with more airbags and EuroNCAP stars than you can shake a stick at. I'm quite happy to drive both, but I'm under no illusions about which of them is likely to protect me better in most accidents. My feeling is that "most people", if safety is a big priority for them, are likely to have a vague idea that "bigger and heavier is safer". And for the most part, they'd be right, of course. Even the copper - supposedly an accident investigation expert, told us he knew which car he'd rather have been in, despite the evidence that it was the driver of the X-Trail who was left permanently disabled, staring him in the face!

So explicit and cynical or not, the inevitable flip side of the choosing a big heavy car "because it is safer in an accident" coin really is choosing to make anybody they collide with less safe.

Broadly, perhaps, but let me put this question to you: In the 1960s and '70s, when cars were a great deal lighter than they are today, did more people die on our roads each year, or fewer?

 

[Bodgedbuild]

And what if it had been a Range Rover at more than twice the weight of that Ibiza?



That's why I kept talking about everything else remaining the same.

If 2606kg had hit the front corner like that, instead of 1293kg?

And if the only reason the driver was in a 2.6 tonne car was that he wanted to do as much as he could to ensure that his car came out on top of any encounter?

As I said, no, I dont think that people explicitly and cynically decide to make life more dangerous for other road users, and yes, the dynamics of accidents are complex and unpredictable.

But they believe that they are safer in a big heavy car.

They know that if they could choose theyd want any car that hits them to be as light as possible. And they know full well why.

So explicit and cynical or not, the inevitable flip side of the choosing a big heavy car "because it is safer in an accident" coin really is choosing to make anybody they collide with less safe.

Being modern is pretty much the most important aspect of car safety, the newest small cars are much safer than even large older cars that were regarded as safe in their day...

 

[Captain Nemesis]

Indeed. But you seem to be wanting to skew reality to fit your position. It was a single track road. The Range Rover is wider than the Ibiza. Assuming it to have been positioned in exactly the same place as the Ibiza, the overlap would have been greater and the X-Trail's crash cans would have done their thing. So what you're really saying, is that suppose someone had magically increased the density of an Ibiza, so that it had the mass of a Range Rover but the dimensions and structure of an Ibiza, thereby allowing it to hit in precisely the same position at the same speed in the same direction, etc, then the outcome would have been worse?

Im trying to make the point that on average/in the long run/in the round/the tendency is/looked at as a whole/generally speaking/etc/etc/etc, when two cars of similar vintage collide it is the smaller/lighter one (and its occupants) which comes off worst.

And everybody knows that. Its why so many people say they want a bigger/heavier car so that they/their family will be safer in an accident. Its why people say theyd rather be collided with by a smaller/lighter vehicle than a bigger/heavier one.

Of course the reality of each individual collision is complex and unpredictable, but would you really claim, that if all the millions of collisions which happen every day were analysed, and adjusted for vehicle age and condition, that there would be no correlation between relative mass and relative damage and relative danger?

So... in your first assertion, you say that you don't think people consciously decide to make life more dangerous for other road users, and in your second, you say that they know full well why they'd want any car that hit them to be as light as possible?

I think the truth lies somewhere between the two.

It doesnt have to lie between the two, as the two are not opposed positions.

Re the second one, this

My feeling is that "most people", if safety is a big priority for them, are likely to have a vague idea that "bigger and heavier is safer". And for the most part, they'd be right, of course.

just states it in a different way.

And I assume that you dont disagree with me when I say I dont think people consciously decide to make life more dangerous for other road users.

But its quite possible for people to do something with consequences without having any conscious or deliberate or thoughtful intention of bringing about those consequences.

But as per what I said above about tendencies and correlation, and what you said above about "for the most part, they'd be right, of course", having no conscious or deliberate or thoughtful intention of making other people less safe does not mean that isnt what someone does when they choose a larger/heavier vehicle.

The only point Ive been trying to get across is that if someone makes a conscious or deliberate or thoughtful decision to buy a bigger than average/heavier than average car because they want to be safer in a collision then they should be prepared to accept that on average/in the long run/in the round/the tendency is/looked at as a whole/generally speaking/etc/etc/etc their increased safety really does come at the cost of reduced safety for others. And not stamp about in denial when someone joins the dots in front of their eyes.

Broadly, perhaps, but let me put this question to you: In the 1960s and '70s, when cars were a great deal lighter than they are today, did more people die on our roads each year, or fewer?

Of no relevance.

 

[Captain Nemesis]

Being modern is pretty much the most important aspect of car safety, the newest small cars are much safer than even large older cars that were regarded as safe in their day...