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Old 5th August 2015, 10:02   #76
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Default Re: Mahindra XUV500 W8: Severe topple, but Side Airbags didn't deploy!

Good to now occupants are safe.

Would request to elaborate on the settings of the gizmos esp. cruise control, ESP. What was the tire pressure last checked.

An over inflated tire can easily cause loss of friction. Not that I say it was the case , which guess I leave it to experts but highway drive require exact or 1-2 units less tire pressure to be maintained.
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Old 5th August 2015, 10:32   #77
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Default Re: Mahindra XUV500 W8: Severe topple, but Side Airbags didn't deploy!

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Originally Posted by Vid6639 View Post
LOL. That article is not right. Airbags will deploy with or without seat belts. If you don't wear seatbelts then the airbags will work as secondary but it is stupid.

Because of not wearing seatbelts you will go towards the steering/dash and the airbag will blow up on your face. This can cause sever injuries.

Only very advanced systems deactivate the passenger airbag when it detects a child in the front seat. Usually if you have a child in front seat, one needs to deactivate the passenger airbag manually.

Effectively airbags will go off regardless of seat belts being worn or not.


No no. side airbags in the seat will deploy along with the curtain bags. The sensors are not on the seats but the trigger mechanism is. So you need to be careful of not putting excessive force.

If the sensor was on the seat then the shell would be compromised before the airbag is useful which would be pointless.
I'm not well versed as you. But my reference was with respect to below link. Thanks for correcting me.

Link :: http://www.team-bhp.com/forum/indian...-seatbelt.html (Airbags don't activate if you aren't wearing a seatbelt?)
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Old 5th August 2015, 10:51   #78
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Default Re: Mahindra XUV500 W8: Severe topple, but Side Airbags didn't deploy!

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Originally Posted by Vasuki View Post
I'm not well versed as you. But my reference was with respect to below link. Thanks for correcting me.

Link :: http://www.team-bhp.com/forum/indian...-seatbelt.html (Airbags don't activate if you aren't wearing a seatbelt?)
I remember that thread. If you read the thread noone has mentioned that airbags won't deploy if seat belts are not worn. The OP there had a question which went into discussion.

Earlier airbags used to cause serious injuries if seatbelts were not worn. Recent years they have changed the airbags to deploy with variable force depending on impact. If you're not wearing seatbelt and your car has a weight sensor, the airbag might be suppressed if it doesn't detect any weight.

However for driver front airbag it's not the case. It will still deploy to try and save the driver from chest injuries due to hitting steering wheel.

Regarding the side curtain airbags, they will deploy regardless of seatbelts as most countries don't have the rule that rear seat belts are mandatory.

Basically if there was a rule that curtain airbags should deploy only when rear seatbelts are worn it would render them useless. Also majority of cars don't have any sensors for rear seat belts.

Last edited by Vid6639 : 5th August 2015 at 10:53.
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Old 5th August 2015, 14:41   #79
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Default Re: Mahindra XUV500 W8: Severe topple, but Side Airbags didn't deploy!

Thank God that all the occupants survived this horrible accident. I would request you to tweet this thread to @anandmahindra, he is very prompt on twitter and addresses the concerns quickly.
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Old 5th August 2015, 22:58   #80
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Default Re: Mahindra XUV500 W8: Severe topple, but Side Airbags didn't deploy!

Firstly Thank God that all the Occupants are safe.

I feel there is equal amount of driver error as well. Irrespective of the speed, looking at the damage and such a bad roll over, I dont think it was below 100KMPH. Are you sure it was only aquaplaning the reason for this roll over?

Pardon me here, no offense but the one who was driving the car has either dozed off or was over confident of his driving in rainy conditions. With 5 people onboard, one must be even more cautious and slow when driving on unfamiliar and uncertain rainy conditions. even 60+ is very dangerous in rainy conditions, forget 90+ thats disastrous be it any car or SUV.

I doubt the condition of the tires either the Tyre pressures weren't checked at all or the condition of the tyre not monitored. Doesn't look like a 8k run tyres to me from the pics.

I feel because of the tall design SUVs are kind of not safe, they are surely sturdy and stronger etc., but I somehow feel the controlling part of these big cars isn't confidence inspiring. Looking at this car, I am having serious doubts about the downgrading quality of Indian automobiles just to sell in more numbers. Bigger is not always better. If this is the fate of a SUV, wondering how sturdy the cars are.

My Personal opinion(Dont mind): It not recommended to lend your car to someone who hasn't been used to driving it. You are risking everyone's life driving in it. Its very dangerous specially for someone who is driving an unfamiliar car/SUV on a highway without being used to driving the car. Occasional drivers and drivers who drive a unfamiliar car are the most risky ones to drive with. Obviously your friend's friend wasn't aware of how the control systems work in the vehicle since he wasn't used to it. Secondly, city Driving and highway driving are two different things, if one is not sure how to be driving where, at-least one can be slow within reasonable limits to be safe and keep the passengers safe. When one is driving around with passengers, realize you have their life in your hands, better be responsible in your actions while driving.

Technology has its own disadvantages too, just like the traction control kicking in when not needed and airbags not being deployed when almost whole of the car is damaged badly. This is serious, the manufacturers cannot escape for the failing of the technology that should have ideally worked. Why are they commanding a price for it then??? its human lives at stake.

One things for sure, the Airbags with so much of impact should have been ideally deployed, the car has sufficient impacts on almost all corners for the airbags to be deployed. Even contact at one point is sufficient for the impact. This is a technical failure clearly, no matter what M&M justifies for the Airbags not deploying, they are liable for a proper compensation in every way to your friend. Regarding the recall of XUVs, if M&M is at fault and this car was in the recall list and not recalled and fixed then M&M is liable for the damages completely.
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Old 5th August 2015, 23:35   #81
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Default Re: Mahindra XUV500 W8: Severe topple, but Side Airbags didn't deploy!

Thanks again for your responses and support.

I got more details on the accident after speaking to my friend. The vehicle was travelling on a 4 lane road in a straight line. There was a thin sheet of water flowing on the highway due to the banking and gradient of the road. There wasn't any column or puddle of standing water. There was a sudden lose of control and vehicle started a 180 degree spin. It then toppled over the edge of the road. On course of the topple, the front right hit a tree (the front headlamp damage is caused because of this) and it bounced back and the rear hit the coconut tree and this ''stabilized'' the situation.

What caused the sudden spin - that's still unknown. My friend visited Mangalore to start the survey and other process. The surveyor suggested the rear left wheel could have jammed or stopped causing the spin. Rear left tyre was the one having lesser thread depth compared to the other 3 wheels. The vehicle had spun towards the left and this kind of validates the claim.

That has somehow rang a bell. He had given the vehicle for service recently. After the service, he noticed a malfunction lamp had lit up for which he took the vehicle back to service center. The issue was diagnosed with the brakes and they rectified this. A wheel alignment was done as well and all these was just before the trip. Again, done at ASC. Just bringing all the facts onto the table. Could this be related? again we do not know this until an expert investigation or analysis is done.

The vehicle should have been updated with the fix for side airbags as it was regularly serviced at Mahindra ASC. As to the structural safety part - remember, this vehicle is meant for 7 people. If there were anyone at the last row, I do not know what could have happened. The front left has caved in as well. I am not sure where the manufacturer is in the thanksgiving list for the people who traveled in the vehicle.

@Sunsh!nes - The person driving the car, I am told is an experienced hand. The accident happend at the morning and they had just started after their breakfast 10 minutes back. So, I would probably junk the sleeping theory.

-
Glen

Last edited by glenmz : 5th August 2015 at 23:43.
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Old 6th August 2015, 10:47   #82
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Default Re: Mahindra XUV500 W8: Severe topple, but Side Airbags didn't deploy!

This is insane, yet all occupants safe; technology has worked.

1. I would doubt on the speed of car. Almost all cars with good engines do triple digit speeds without fuss, with 140 horses under the hood, it should well be the case for SUV. The driver may not be aware of it or would have seen it split seconds before mishap when the car was retarding. Come what may atleast for the body shell, Mahindra has done a good work.

2. One has to see and analyze the logic and protocols that manage and control the airbag deployment. If the protocols need a change, this car could be a good case for analysis; Mahindra can consider taking this car for detailed analysis / deep diving and fix the airbag issue if it is really there so that appropriate sensors may be installed to capture these kinds of circumstances.

3. What is the process for getting insurance claim as the vehicle has been totaled, no injuries to occupants as well as to any third party as well as damage to public property. Also, no offences - anything related to driving under influence of drugs (alcohol or may be even simple cough and cold medicines)? Has any test been conducted on the person behind wheels? The driver has already accepted the driving speed of 90 kmph, which may be over and above the permissible speed on the road or may be just the max. permitted speed. What happens if the speed of car is above the suggested max speed on a highway - any changes at insurance?
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Old 6th August 2015, 10:50   #83
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Default Re: Mahindra XUV500 W8: Severe topple, but Side Airbags didn't deploy!

This is an interesting research study I came across reading about rollovers and airbags - http://www.ircobi.org/downloads/irc12/pdf_files/16.pdf

Looking at the state of the cars in the research (cars doing similar speeds and involved in rollover crashes just as the XUV), I don't think Mahindra has done too bad on the structural integrity front of the XUV.
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Old 6th August 2015, 15:11   #84
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Default Re: Mahindra XUV500 W8: Severe topple, but Side Airbags didn't deploy!

Quote:
Originally Posted by glenmz View Post
Thanks again for your responses and support.

@Sunsh!nes - The person driving the car, I am told is an experienced hand. The accident happend at the morning and they had just started after their breakfast 10 minutes back. So, I would probably junk the sleeping theory.

-
Glen
Good to know it was an experienced hand behind the wheel and my thoery is wrong to conclude about the driver having slept. But after reading your comments now, there could be malfunctioning of the car left wheel as you say the tread is not evenly worn out.

Any reasoning giving or hints for the airbags not having deployed despite such an impact? There has to be something really strong reason and it has to be technical issue only.

Last edited by Technocrat : 11th August 2015 at 23:06. Reason: Please quote selectively as a large quoted post causes inconvenience to our mobile users, thanks
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Old 8th August 2015, 18:29   #85
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Default Re: Mahindra XUV500 W8: Severe topple, but Side Airbags didn't deploy!

Mr. Srinivas - Principal Chief Engineer, Mahindra Automotive - wrote the following email to the XUV500 owner. This email was shared with me by Mahindra.

Quote:
Dear Mr. Thomas Murickan,

I have received your email dated 31st July 2015 addressed to our customer care department and respond as below.

At the outset, we are pained to learn about the accident of your XUV500 (bearing registration No. KL39D 9393) near Suratkal in Karnataka. It is an unfortunate incident, and we at Mahindra are relieved to hear that all of the occupants of the car are safe.
We will investigate this incident further in more detail. However our preliminary comments and observations about the incident, after studying and analysing the available information and photographs, are as follows:

1. Based on information we have gathered till date, and as you have also correctly concluded in your email, the cause of the accident appears to be “aquaplaning” which has resulted in toppling of the vehicle. The Electronic Stability Control (ESP) as a function, uses selective braking of wheels to stabilize the vehicle during “under steering” and “over steering” situations. Typically, during an “aquaplaning” situation, contact between wheel and ground, would be lost temporarily, resulting in loss of traction preventing the vehicle from responding to control inputs. Hence in aquaplaning situations, ESP will not be able to play any meaningful role. From the images, it appears that both of the rear tyres are completely worn out. It is well established that vehicle dynamics are significantly dependent on the condition of the tyres. Worn tires, especially bald ones, can easily lose traction on wet roads, where the grooves aren't deep enough to channel water out from beneath the tread resulting in “aquaplaning” situations. We also note from the images that the original tyres have been replaced, though we are not at this time able to ascertain the specifications of the replacement tyres used or as to how this aspect could have contributed to the “aquaplaning”. As a technical person, I would urge that in the interest of safety, please always use tyres meeting specifications recommended by the manufacturer and which are in good condition, especially when driving in bad weather conditions.

2. The XUV500 is equipped with front and side airbags. Front airbags would deploy only during frontal impact condition at specified speeds. In this case, there is no damage seen in the front of the car. As there was no frontal impact the front airbags had not deployed. Side Airbags too are designed to deploy in case of acceleration due to impact. Since the toppling was caused due to “aquaplaning” situation and not due to side impact collision, the side airbags also would not have deployed in this case.

3. In our experience, in accidents of such kind, it is the safety cage integrity and seat belt usage that play the most significant role in reducing injuries and risk to life and that aspect of XUV500 design seems to have significantly contributed to avoiding any serious injury in this unfortunate accident.

We wish to assure you that we at Mahindra, always consider safety as our top most priority. Our customer Care team will be in touch with you to further investigate this accident.

warm regards,

Srinivas
Principal Chief Engineer

CC: Customer Care
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Old 8th August 2015, 20:16   #86
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Default Re: Mahindra XUV500 W8: Severe topple, but Side Airbags didn't deploy!

From the discussions what i understood is that the tyres were used for 8000 kms , The FRONT Tyres; and the rear tyres were wornout. Was that the major reason for this unfortunate accident ?

"when you replace only 2 tyres, the new pair should be in the back." The second url shows a video demonstration this.

http://www.popularmechanics.com/cars...unked-10031440

http://www.discounttire.com/dtcs/infoTiresRear.do

Last edited by vinodv001 : 8th August 2015 at 20:19.
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Old 8th August 2015, 23:01   #87
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Default Re: Mahindra XUV500 W8: Severe topple, but Side Airbags didn't deploy!

Quote:
Side Airbags too are designed to deploy in case of acceleration due to impact. Since the toppling was caused due to “aquaplaning” situation and not due to side impact collision, the side airbags also would not have deployed in this case.
Will be interesting to have views from experts on this , I am not very convinced on side curtains not being deployed in this case , is it possible that Mahindra has wired / programmed side bags to work in conjunction with front bags depending on severity / position of hit ? can someone confirm having seen any Mahindra vehicle with only side airbags deployed in case of side impact ?
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Old 9th August 2015, 08:36   #88
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Default Re: Mahindra XUV500 W8: Severe topple, but Side Airbags didn't deploy!

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Originally Posted by Turbanator View Post
I am not very convinced on side curtains not being deployed in this case , is it possible that Mahindra has wired / programmed side bags to work in conjunction with front bags depending on severity / position of hit ? can someone confirm having seen any Mahindra vehicle with only side airbags deployed in case of side impact ?
I'm not convinced too with the reason given by Mahindra. Aquaplaning could have been the reason for the spin to start. However, once the car hits the tree sideways (or) rolls, there will be "considerable side impact" that should be enough to trigger the airbags. While I commend Mahindra to respond to customer inputs and send out a reply, I feel that they are not being too honest with their response.
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Old 9th August 2015, 13:17   #89
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Exclamation Re: Mahindra XUV500 W8: Severe topple, but Side Airbags didn't deploy!

Its heartening to know all the occupants are safe. We don't give much importance to safety in our country and this is also evident in the driving patterns on Indian roads and the alarming numbers of accidents reported everyday. If one does invest in a premium for the added safety features like airbags and such it is the responsibility of the manufacturers to ensure these are always operational. Whatever the story maybe in this case Mahindra is not isolated . Toyota had the same problem on its fortuner a few years back.
(http://www.team-bhp.com/forum/indian...nt-deploy.html (Toyota to pay 25 lakhs for Fortuner Accident (airbags didn't deploy))).
Hopefully the day will come when all drivers in our country are safety conscious and give life the importance it deserves.
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Old 9th August 2015, 15:47   #90
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Default Re: Mahindra XUV500 W8: Severe topple, but Side Airbags didn't deploy!

Incidents like these further reaffirm my belief in buying only NCAP certified Europeans than desi tin cans
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