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Old 11th July 2013, 09:51   #16
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Default re: Evasive manoeuvres & Rollovers?

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Originally Posted by gthang View Post
Indian magazines don't do such useful testing unfortunately. But if you understand the principle, and get an open road which can be used as a skidpad, one can test for oneself their car's limit's.
This cannot be tested by magazines. Please keep in mind that auto magazine reviewers are not professional test drivers with any advanced training or rally experience, who know how to push the vehicles to the limits. Reviewers are normal people who are picked for their writing skills and interest in cars. Their driving ability is no different than the average joe behind the wheels.

This kind of destructive testing should be left to professional drivers who are trained in testing cars.
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Old 11th July 2013, 10:23   #17
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Default re: Evasive manoeuvres & Rollovers?

Thanks to the mods and govigov for refocusing this thread appropriately. Do we have any hard evidence in the Indian scenario?
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Old 11th July 2013, 10:51   #18
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Default re: Evasive manoeuvres & Rollovers?

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Thanks to the mods and govigov for refocusing this thread appropriately. Do we have any hard evidence in the Indian scenario?
In indian scenario most likely scenario on single carriageway state highway is that you may need to save a cyclist or a dog by taking 2 tyres on gravel some 6- 8 inches below the turmac.
A high GC high mass SUV survive this but low slung cars have a problem.

Breaking and cornering at 140 even on 4 lane highways is a remote possibility unless you want to do rally style driving. Even in a sedan you can touch these speeds only if visibility is clear for atleast 1 KM and you can clearly spot if no truck etc is parked on the side.

So under these circumstances there is no difference between SUV and Car.

NOTE : Before some one chids me and reminds about law on overspeeding let me tell you in several states like Karnataka and AP on a highway there is no upper limit by law unless explicitly stated.

Whereas in states like punjab and Hariyana there is an implied upper limit if not stated ( example don't cross 60 if there is no sign board)
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Old 11th July 2013, 10:57   #19
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Default re: Evasive manoeuvres & Rollovers?

Whatever the tests performed on an SUV, or not, one thing that EVERYONE must understand, is that an SUV is basically a GO-Anywhere (relatively speaking) vehicle, and NEVER a track machine that can be thrown into corners or meant to be driven too hurriedly, irrespective of the level of technology, refinement or price.

Most people I see around me, end up buying an SUV / SUV-like vehicle for the wrong set of reasons.
For this the manufacturers are, to a large extent, to blame. A lot of SUV advertisements promote wrong usage and driving patterns for SUV's and inspire people to mimic them in real life, with disastrous consequences. Surely, that should violate some standards for advertising! Examples - Bolero, Sumo Gold, Safari Storme ads.
Even some of our esteemed forum members rave about a Thar's ability to do 140-150 kmph comfortably on a highway, but pay no heed to the danger they put themselves and the other occupants in, when pulling such stunts. Surely we, the forum members, should be wiser than that!

Having said that, in the scenarios described, most vehicles may topple. However, for any given scenario, the tendency of an SUV to topple will be far higher than than of a low slung sedan.

Last edited by roy_libran : 11th July 2013 at 10:59.
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Old 11th July 2013, 11:13   #20
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Default re: Evasive manoeuvres & Rollovers?

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Originally Posted by amitk26 View Post
In indian scenario most likely scenario on single carriageway state highway is that you may need to save a cyclist or a dog by taking 2 tyres on gravel some 6- 8 inches below the turmac.
A high GC high mass SUV survive this but low slung cars have a problem.
Amit - You are nuancing a slightly different use case and your point is completely valid.

However, my question is about vehicle capability, not use case. How would our vehicles perform in similar "moose" tests?

Just as we would enquire about our Indian vehicles' NCAP ratings.
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Old 11th July 2013, 12:48   #21
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Default re: Evasive manoeuvres & Rollovers?

This is one topic perfect for verbal duels and debates, none of which would be applicable to real world driving.

There are too many variables on which the survival (or more specifically, rollover) of a SUV will depend, and doing an elk test doesn't really give any definite answers. Almost all he SUVs in the video posted by govigov are on the verge of rolling, or actually roll - except the Duster, which fishtails out of control.

Would a car/SUV that fishtails into oncoming traffic be better able to survive than another vehicle that lifts off the inner tyres from the road over a certain speed (and can topple if pushed harder)?

Now, as Sutripta asked before, what would be the results, do you think, if the elk test was conducted on a frozen lake surface or on a skid pan?
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Old 11th July 2013, 13:04   #22
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Default re: Evasive manoeuvres & Rollovers?

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Originally Posted by Samurai View Post
This cannot be tested by magazines. Please keep in mind that auto magazine reviewers are not professional test drivers with any advanced training or rally experience, who know how to push the vehicles to the limits. Reviewers are normal people who are picked for their writing skills and interest in cars. Their driving ability is no different than the average joe behind the wheels.

This kind of destructive testing should be left to professional drivers who are trained in testing cars.
It's unfortunate that the whole concept of auto reviewing has been reduced to just who can write more flowery words. They usually get the best treatment at the junkets too, I imagine.

Please understand what lateral acceleration test is and how they are conducted by real reviewers before terming it as destructive testing.

The lateral acceleration capability of a vehicle best describes it's stability in a corner, and has been the benchmark for handling for many years now.

The Elk/Moose test is an extreme avoidance maneuver that depends as much on the driver's response as it does on the vehicle dynamics. A Moose/Elk scenario very rarely should happen under normal Indian driving conditions unless you are doing high speed lane changes which should not be encouraged anyways.

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Old 11th July 2013, 13:10   #23
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Default re: Evasive manoeuvres & Rollovers?

Higher Ground Clearance and stance generally = Higher Centre of Gravity.
Higher Centre of Gravity = Higher propensity to topple when swerving at higher speeds.

From experience I can tell you swerving to avoid a vehicle/ animal at speed in a Scorpio has frightened me out of my skin in the past. Hence I never generally went at higher speeds than 110kmph in the Scorpio even on a superbly surfaced first class highway.

With the Yeti, which comes equipped with ESP and all the squillions of other safety aid related acronyms, the general behaviour is exactly like a car. One does not jump out of one's skin if one has to swerve, as I experienced one and a half years ago on the road to Chennai when I swerved to avoid an ambling cow that stepped off the divider onto the road all of a sudden.

Crossovers and lower slung SUV's in general behave much better than those older, higher set ones, in situations of this kind.

Whatever it is, I think it is very important to keep within the speed limits and regardless of the type or quality of vehicle one is driving, the optimum speed in India is no more than 110kmph, given our horrendously unpredictable road conditions.
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Old 11th July 2013, 14:05   #24
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Default re: Evasive manoeuvres & Rollovers?

In the video there is a small red car , i guess by FIAT .The handling of same shows FIAT handles well like few other can.
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Old 11th July 2013, 14:37   #25
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Default re: Evasive manoeuvres & Rollovers?

ESP with Roll over Mitigation is one of the most important safety features when it comes to SUVs with high COG and soft suspension, a feature which most manufacturers conveniently choose to ignore for our market. Obviously it cannot compensate completely for bad handling behavior.

Some examples- Few years back in South Africa there was a lot of controversy surrounding Fortuner. A few Fortuner owners experienced scary Handling and Rollovers, even the Media carried out a few tests to verify this. Initially Toyota denied any such behaviour in Fortuner, but later they did some modifications which included added ESP and full time All Wheel Drive. Unfortunately Manufacturers love taking us Indians for a Ride, initially the only variant of Fortuner sold in India had Full time AWD as standard but ESP was missing, later at the time of facelift they added ESP to single variant but two other variants were added which do not come with either ESP or Full time AWD. I do not mean to say that Fortuner is a unsafe vehicle, i know a lot of other vehicles which are even more prone to loss of control/roll over. I want to highlight the fact that to save a few bucks, the manufacturers skip out on essential safety kit they offer as standard in other markets.

Similar post: http://www.team-bhp.com/forum/street...ml#post2627861 (Toyota Fortuner crashes, Air bags did not deploy *EDIT* Another similar case Pg.7)

Similarly, Dacia Duster, the world's cheapest SUV, known as Renault Duster in our market and sold as a premium SUV also has some stability issues. The non ESP equipped it known for scary handling behaviour and even toppling, it also failed the Moose/Elk test somewhere in Europe. No need to guess, ESP is not offered in Indian Duster, not even in the top variant, not even as an option.

Related article: http://www.autolatest.ro/news-cars/d...10-moose-test-





Quote:
Originally Posted by roy_libran View Post
Whatever the tests performed on an SUV, or not, one thing that EVERYONE must understand, is that an SUV is basically a GO-Anywhere (relatively speaking) vehicle, and NEVER a track machine that can be thrown into corners or meant to be driven too hurriedly, irrespective of the level of technology, refinement or price.
I disagree with the generic classification. The word SUV nowadays is used for a very broad range of vehicles. A generic classification like SUVs cannot be taken a race track or every SUV is good at offroading is not right. For example- Your Gurkha is a SUV and even CRV is also classified as SUV. CRV can be driven like a car, infact it outperforms many low slung cars on a racetrack but it absolutely cannot go hardcore offroading, similarly the Gurkha can conquer all kinds of offroad trails but it cannot be thrown around like a car on good roads. Ask the media people who were invited to drive the XUV on BIC.


Quote:
Most people I see around me, end up buying an SUV / SUV-like vehicle for the wrong set of reasons.
I agree. Most SUV buyers do not know why they want to buy the SUV. Most of them buy just for the Butch looks, feeling of space or extra ground clearance(or maybe some other reasons). They really have no idea how unsafe a traditional SUV can be in an emergency swerve. Similarly if they end up with Monocoque, they find it hard to digest a CRV/Outlander cannot take abuse but a Fortuner/Endeavour can.
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Old 11th July 2013, 14:44   #26
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Default re: Evasive manoeuvres & Rollovers?

With Explorers toppling regularly, manufacturers started adopting roll over mitigation equipment for close to a decade now. Guess they still come in very high premium vehicles in India.
An SUV is meant to be taken out for performing other sporty things, not to indulge in sports with.
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Old 11th July 2013, 14:49   #27
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Default re: Evasive manoeuvres & Rollovers?

As Anshuman stated, most manufacturers including the famous Toyotas and Hondas and Suzukis and Renault/Nissans etc of the world, place a very nominal or indeed, low value against the lives of us Indians.

Indian manufacturers? The less said the better.

We Indian buyers, of course, with our miserable, scrounging "kitna deti hai" mentality, only invite such treatment too!

However, on this august forum as also on many other fora it almost seems to come across as a heinous crime if like me, one speaks out against manufacturers like these, for some reason. People, it seems, are always quick to take up the cudgels on behalf of Toyota and Honda and are equally willing to continually throw brickbats at all the other chaps, especially the Euro chaps! From a safety engineering standards point of view I think it is pretty clear that the Euro chaps are generally much better off than the others, at least as far as the vehicles sold here in India are concerned.

From the safety and conformance plus features standpoint, Toyota, Honda and all the rest of them are simply fleecing us Indians and we are lapping it up too! These vehicles are most certainly overpriced for what they offer.

It is abundantly clear that these manufacturers do certainly follow "double standards" when compared to their vehicle specs and conformances in Europe or other developed markets vis a vis the Indian market.

Last edited by shankar.balan : 11th July 2013 at 14:57.
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Old 11th July 2013, 15:00   #28
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Default re: Evasive manoeuvres & Rollovers?

Drive a SUV like a SUV - knowing that it suffers from some inherent disadvantages w.r.t. height, high ground clearance, stopping power (due to weight), aerodynamics etc.

These academic exercises mean nothing. You need to get familiar with a vehicle to understand to know what that vehice can do and can't do. Only then you can start pushing it.

Do not attempt to drive it like a low slung sedan or hatchback based on marketing messages.

This is basic physics, no need to overengineer things like you seem to be doing.

This is true for Cayennes as well as for Scorpios (and not just limited to SUVs): take time to understand what that vehicle can do before pushing it. Crawl, walk and then run. Research, and then test it out gradually.

After driving in Indian highways at pretty high speeds, I can say that go over 110-120 kmph - based on vehicle capabilities - only if you know that you can handle a animal/human jumping on the road/appearing out of the blue (or say a huge truc coming the ulta way - and you see it at the last moment after you take a blind turn at high speeds). Which means straightish roads, where you have adequate visibility to REACT - on both sides of the road as well as through the divider if there is a divider.

P.S. Google 'Elk Test' and you will get many links that will make you think.

Last edited by nilanjanray : 11th July 2013 at 15:05.
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Old 11th July 2013, 15:01   #29
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Default re: Evasive manoeuvres & Rollovers?

All SUVs with high stance, high GC do come with a warning on the sun visor.
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Old 11th July 2013, 15:03   #30
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Default re: Evasive manoeuvres & Rollovers?

The same logic of high centre of gravity and prone-ness to toppling holds good for those Tall Boy cars like the WagonR, the Estilo, the Ritz, the Santro and others, all of whom have tiny short little wheels to boot!



Quote:
Originally Posted by nilanjanray View Post
Drive a SUV like a SUV - knowing that it suffers from some inherent disadvantages w.r.t. height, high ground clearance, stopping power (due to weight), aerodynamics etc.

These academic exercises mean nothing. You need to get familiar with a vehicle to understand to know what that vehice can do and can't do. Only then you can start pushing it.

Do not attempt to drive it like a low slung sedan or hatchback based on marketing messages.

This is basic physics, no need to overengineer things like you seem to be doing.

This is true for Cayennes as well as for Scorpios (and not just limited to SUVs): take time to understand what that vehicle can do before pushing it. Crawl, walk and then run. Research, and then test it out gradually.

P.S. Google 'Elk Test' and you will get many links.
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