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Old 13th November 2020, 11:01   #121
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Default Re: Tata Nexon: Global NCAPís first 5-Star Indian car

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Originally Posted by extreme_torque View Post
The comment in question is perhaps one of the most asinine comments I have come across on teambhp and I am not kidding. Alloy wheel design, front bumpers effect crash test rating? We need to understand what a crumple zone is and what is the load bearing structure of a car to absorb crashes. So unless Tata skimped and made changes to the structure of the car after NCAP testing, the ratings would still remain the same when tested against the same parameters.
I too thought that his answer was not satisfactory, but as I don't have much knowledge about the factors which influence the structural strength of a car, I felt that he had got some point (though the point about how the alloy wheel design affects crash test rating is not at all acceptable). Thank you for your explanations.
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Old 28th June 2021, 04:14   #122
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Wakey wakey, it's time to revive a dead thread! Fortunately for me, it hasn't been locked— yet. I doubt if anyone will ever read this, but for what it's worth, I'll pen down some new findings of mine— well, technically not mine; it would be disingenuous to take all credit and present them as something I thought of on my own. I'll credit the inspiration for the highly speculative post that is about to follow. It will involve a lot of tomfoolery and mental gymnastics, so if anyone is reading this and still wishes to continue on this futile endeavour, here is your viewer discretion is advised warning. And no, you won't get these precious minutes of your life you just spent reading this back.

First of all, I would like to thank the source of my inspiration and essentially the very core of my speculation.
Tata Nexon: Global NCAPís first 5-Star Indian car-screenshot_202106280044492.png

Some background: I have been frequenting GNCAP's YouTube channel ever since Autocar's rumour suggesting that the Kiger is in for a test at GNCAP. I was casually strolling through some videos on their channel, checking out the description for additional information/comments about those crashes until this comment right here, with the black profile picture piqued my interest. If you don't know Hindi, the commenter points out that the code assigned to the 4-star Nexon test vehicle exactly matches the one used by the 5-star Nexon test vehicle. He questions why the same video has been used for the 5-star Nexon, as he is confused (probably) about the legitimacy of these tests.

As I set out to investigate the claim made by the commenter, I found the following:

Tata Nexon: Global NCAPís first 5-Star Indian car-screenshot_202106280057522.png


Tata Nexon: Global NCAPís first 5-Star Indian car-screenshot_202106280055392.png

What's the difference, you ask?
Well, one is titled Nexon scores 4 stars while the other is titled India's first 5 star car.

Further, if you look at the codes on the rear door of both the Nexons, it reads: OD2618TNE1

Q: What's the big deal then? It's just some technical mumbo jumbo they might be using for Nexons in particular, right?
A: Well, here's the technical mumbo jumbo on the side impact test:

Tata Nexon: Global NCAPís first 5-Star Indian car-screenshot_202106280045462.png

It reads: MD4518TNE1

Q: What is this mumbo jumbo?
A: I haven't fully deciphered what each and every letter and number means, but lets look at a few more of these codes from another car.

Tata Nexon: Global NCAPís first 5-Star Indian car-screenshot_20210628023034.png

Tata Nexon: Global NCAPís first 5-Star Indian car-screenshot_20210628023130.png

For the offset test, the Altroz reads: OD0220TAL1

For the side impact test, the Altroz reads: MD0220TAL1

We see some similarities and some differences. What I have worked out after looking at half a dozen other tested cars and thinking (to myself) for about half an hour or so, is as follows:

1. OD stand for Offset Deformable, while MD stands for Mobile Deformable.

2. The first letter T in TAL stands for the car manufacturer, in this case Tata. The succeeding AL represents the initials of the car— ALtroz. Similarly for Nexon, TNE means Tata NExon.

3. The 18 in Nexon's OD2618TNE1 and MD4518TNE1 stands for the year in which the car was tested, i.e. 2018. Similarly for Altroz, the 20 in OD0220TAL1 and MD0220TAL1 represents the year 2020.

4. Now this is the part where I'm not really sure about my speculation. I think that the 26 in OD2618TNE1 stands for the 26th week of the year 2018, whereas the 45 in MD4518TNE1 stands for the 45th week of 2018, meaning that the Nexon for ODB test was in the lab by the 26th week of 2018, whereas the Nexon for the MDB test arrived in the lab only by the 45th week of 2018. It doesn't make sense for Tata to have sent their 5-star Nexon with the updated chassis the same week they sent the Nexon which eventually got a 4-star, because the result of the 4-star Nexon was published much later (about a month at least). This speculation is solidified by looking at the codes on the Altroz— 02 in OD0220TAL1 and MD0220TAL1 stands for the 2nd week of 2020, according to me. So, both the ODB and MDB vehicles for Altroz arrived in the 2nd week of 2020, unlike Nexon.

The reason I'm kind of unsure about this week theory part is because LATIN NCAP and EURO NCAP's publishing guidelines are something like this:
Quote:
6.1.4. Euro NCAP will inform the vehicle manufacturer in advance of the target date for publication of the result on the website. In general, this date will be no later than two months from the date of arrival of test vehicles at the laboratory.
6.1.5. Where a vehicle has been retested, the following applies:
6.1.5.1. The rating will, if possible, be published as originally intended. If the original release
date cannot be met, the result will be published as soon as possible after the originally-
intended launch date (but no more delayed than 3 months).
If I assume that GNCAP follows the same guidelines (since I cannot find their own guidelines), there has been a very recent case where this guideline has not been followed. It is none other than the Renault Triber.
Tata Nexon: Global NCAPís first 5-Star Indian car-screenshot_20210628030145.png

OD0521RTR1 means that the car has been in the lab since 5th week of 2021, i.e. somewhere around the beginning of February this year, while the results were published on 1 Jun, almost 4 months later. To give GNCAP the benefit of the doubt, and assuming my speculation is correct, these are unprecedented times and EURO NCAP has written that this is what they generally follow, not something absolute.

5. I do not know what the digit at the end stands for. It is generally a 1, but in case of XUV 300, it was OD0320MXU1 for ODB test and MD0320MXU2 for MDB test.
Tata Nexon: Global NCAPís first 5-Star Indian car-screenshot_20210628031549.png
Tata Nexon: Global NCAPís first 5-Star Indian car-screenshot_20210628031616.png

Compare this to the Altroz where it was 1 at the end for both the tests and I'm not able to reasonably conclude anything about the last digit.


So where does this all lead me to? Am I suggesting that GNCAP tests are rigged?
No. The point here is that many of us believed that Tata sent a new Nexon with some improvements in its chassis even for the ODB test to get a 5-star rating, which may not necessarily be the case in the wake of these findings. The improved protection to the upper leg / thigh region definitely supported that assumption.

What I think would have happened, is that, instead of sending a new vehicle for ODB test, Tata showed GNCAP their own in-house crash data (since they have their own crash testing facility) after they made changes to the chassis. GNCAP would have verified the documents demonstrating the changes to the chassis and checked whether Tata's in-house crash data correlates to the documents submitted by them. After they were satisfied with their investigation, they would have accepted Tata's crash test data and given the Nexon a five star rating, after it passed the side impact test and scored a perfect 1 point in SBR.

If anyone manages to read this confused rambling, do let me know what you think of this speculation.

Last edited by Aditya : 22nd October 2021 at 19:04. Reason: As requested
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Old 28th June 2021, 18:59   #123
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Default Re: Tata Nexon: Global NCAPís first 5-Star Indian car

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Originally Posted by rpm View Post
Wakey wakey, it's time to revive a dead thread! Fortunately for me, it hasn't been locked— yet......do let me know what you think of this speculation.
Could it be that just the added safety features and the side impact test were enough to improve the score and score an extra star? Global NCAP does not mention of Tata having made any structural improvements to the Nexon, thus requiring no retest(?).

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Last edited by Nexusios1521 : 28th June 2021 at 19:12.
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Old 28th June 2021, 19:14   #124
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Default Re: Tata Nexon: Global NCAPís first 5-Star Indian car

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Originally Posted by rpm View Post
If anyone manages to read this confused rambling, do let me know what you think of this speculation.
Quote:
In case of an accident, this system might lock the doors of the vehicle, preventing its occupants from safely exiting it. Global NCAP, which evaluates a vehicle’s safety rating based on a number of different parameters, awards its 5-star rating (highest) to those vehicles which do not have automatic door-locks as a feature. Tata Motors, in a recent update to its compact hatchback Tiago, removed the said feature in sync with the GNCAP’s regulations for the same to score the top-star rating. The homegrown automaker’s sub-compact SUV, Nexon had recently scored the coveted 5-star rating in GNCAP’s crash test.
Source: https://www.financialexpress.com/aut...ained/1730371/


Actually there was quite a discussion over this feature deletion back in the day. People were upset about about the feature deletion, and that it was a security hazard (as someone might just open the door, grab your laptop on the rear seat, and run away while you are stuck in traffic) etc.

Something similar happened with the Thar recently. The Thar front-facing was tested, and got 4 stars. But GNACP said we will let you advertise this as a 4-star car, only if you discontinue the side facing variant (which doesn't even have rear seat-belts). And Mahindra did as asked, and discontinued the Thar AX, making the AX side-facing seat variant rarer than a unicorn.


PS: I really dislike Tata Motors, and everything that they do, so, if anything I can be accused of having an anti-Tata bias, instead of in favour of them, but lets not go down the lane of conspiracy theories, especially not on this forum.

Last edited by vb-san : 29th June 2021 at 05:20. Reason: Typos
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Old 28th June 2021, 21:16   #125
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Default Re: Tata Nexon: Global NCAPís first 5-Star Indian car

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Originally Posted by Nexusios1521 View Post
Could it be that just the added safety features and the side impact test were enough to improve the score score an extra star? Global NCAP does not mention Tata making any structural improvements to the Nexon, thus requiring no retest(?).
To be eligible for a 5-star rating, certain requirements must be met. Let's have a look.

1. The car must score minimum 14.00/16 points in the offset deformable barrier test itself. Do note that this score only includes the ODB test, not the SBR. The 1 point allotted to SBR is a separate requirement independent of the ODB score.

2. The car must score a perfect 1 point for SBR.

3. The car must pass ECE95 side impact test.

4. The car must have 4 channel ABS.

Let's have a look at the crash result pdf of both, the 4-star Nexon and the 5-star Nexon.
Tata Nexon: Global NCAPís first 5-Star Indian car-screenshot_202106282027102.png

Tata Nexon: Global NCAPís first 5-Star Indian car-screenshot_202106282037242.png

As you will observe, the 4-star Nexon managed a 4-star rating with a score of 13.56.
It had 4-channel ABS, so the 4th requirement had already been fulfilled. While SBR was present, the pdf clearly mentions SBR for only the driver, meaning, it scored only 0.5 points in SBR.

The scoring criteria for SBR is as follows:
Quote:
Global NCAP will assess SBR in the front seating positions according to Euro NCAP Assessment Protocol Ė SA Version 5.6 or later (Chapter 3). SBRs will give 0.5 point for the driver seating position and 0.5/N point for each front passenger position that meets the requirements (N is the number of available front passenger positions). Hence the maximum number of SBR points achievable is 1. A car is eligible for scoring SBR points if the following conditions are met: - The driver and front passengerís head, neck, chest score are orange, yellow or green.
Now, if we shave off 0.5 points from the total score of 13.56, we get the score for the ODB test, i.e. 13.06.
Since this Nexon didn't score 14/16 in ODB itself, it wasn't eligible for further evaluation for a 5-star rating, meaning that any number of side tests and safety features would not have made any difference to its rating, unless they made changes which could affect the ODB score and catapult it beyond the 14 point threshold. This is also evident in the crash result pdf, as we see the upper leg / thigh protection increase from marginal (orange) to good (green), giving it the needed push to be eligible for further testing in the form of side impact test. Once it passed that, it just needed passenger side SBR to cement its 5-star rating, because all other features were already present in the 4-star Nexon except the ODB score and passenger SBR.

Just as a fun exercise, let us consider your scenario where additional safety features would have made a difference. The only difference in safety features between the 4-star Nexon and the 5-star Nexon which represents such a possibility is the SBR. You'll see in the pdf that 4-star Nexon only had driver side SBR, while 5-star Nexon had both, driver and passenger SBR. If, for example, they just made changes to SBR and applied for a 5-star rating / retest with the unaltered 4-star Nexon, the following would happen:

1. Passenger side SBR would grant the 4-star Nexon an additional 0.5 points, taking its total score to 14.06/17.

2. It would still get a 4-star rating because its ODB score would still be 13.06.

So, for a 5-star rating, the minimum overall score needed by a car is 14 points ODB + 1 point SBR = 15.00/17 points.
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Old 28th June 2021, 22:03   #126
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Default Re: Tata Nexon: Global NCAPís first 5-Star Indian car

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Originally Posted by rpm View Post
It doesn't make sense for Tata to have sent their 5-star Nexon with the updated chassis the same week they sent the Nexon which eventually got a 4-star, because the result of the 4-star Nexon was published much later (about a month at least).
I'm glad someone finally pointed this out, because I had noticed it too. I have reason to believe the second frontal crash test for the Nexon never happened. If you observe the thumbnail images on the Global NCAP website, one seems to have brighter colour but on closer inspection of the video, it appears that the test is the same.

Regarding your speculation about the score, your observations seem sound. A minimum of 14 points in the ODB test + 1 point for SBR (thus a total of at least 15 out of 17 including the full SBR point) + UN95 side impact pass + 4-channel ABS are required for the 5th star. Since the Nexon scored 13.56 in the first test and probably already scored half a point for driver SBR - I don't see any comments about it not meeting requirements - (meaning the ODB test score is probably 13.06), it scored 4 stars. Now, the UN95 side impact and 4-channel ABS contribute nothing to the overall score, they're merely 5-star requirements. So, how did the score jump from 14.06 to 16.06? Well, here lies your answer.

The ODB test score did increase despite a second test not being conducted by Global NCAP. Observe the comments and the colour-coded dummies in both reports and you'll see that the ratings for all driver and passenger knees increased from orange to green. This is because the one-point variable contact modifier for each leg was removed by Global NCAP, presumably following a sled test conducted by Tata. (since knee modifiers are not a structural issue, they may be assessed without a destructive test.

Quoting the Global NCAP Adult Occupant Protocol, Section 3.2.1.3: Knee, Femur and Pelvis
Quote:
CONCENTRATED LOADING
The biomechanical tests, which provided the injury tolerance data, were carried out using a padded impactor which spread the load over the knee. Where there are structures in the knee impact area which could concentrate forces on part of the knee, a one point penalty is applied to the relevant leg.
Where a manufacturer is able to show, by means of acceptable test data, that the Variable Contact and/or Concentrated Loading modifiers should not be applied, the penalties may be removed.
Quote:
REMOVAL OF KNEE MODIFIERS
Global NCAP allows the vehicle manufacturer to present evidence in the form of knee mapping data in order to remove applied knee modifiers. Tests must be performed according to the Euro NCAP Sled Test Procedure Version 2.7 or later and carried out using original components only. Global NCAP reserves the right to witness the test. Knee mapping data will be accepted under the conditions below:
- The driver and front passenger’s head, neck, chest score are orange, yellow or green.
- Femur loads <3.8kN in the full vehicle test.
- Knee Slider <6mm in the full vehicle test.
- No structural modifiers applied i.e. integrity of the passenger compartment and/or footwell rupture. - A-pillar displacements must be below 65mm (using the standard Euro NCAP measurement).
Knee mapping data must be presented for review before the 1-2-1 meeting.
If you notice most 4-star cars on the market, knee protection seems to be the only weak area for most of them. I wonder how many 4-star cars would fare better if manufacturers used this provision for removal of the knee modifier.

Just for example (I'm picking the best 4-star car I can find here), the Honda Amaze (or at least the South African one) scores a rather impressive 14.08/17 including half a point for driver SBR, which means that the ODB score is 13.58. Now I can't say for sure that Honda would qualify for removal of the knee modifiers, but in a hypothetical situation where these modifiers could be removed, the ODB test score would stand at 15.58, then if Honda added passenger SBR, the total score out of 17 would stand at 16.58 leaving the Amaze a UN95 side impact test away from being a 5-star car. Effectively, removing even one modifier could let Honda pass the 14/16 ODB threshold. However this is just a huge assumption and I request readers not to assume anything from what I've said in this paragraph. Unless tested again all current 4-star cars including but not limited to the South African Honda Amaze are still 4-star cars, it's merely an example. (The Amaze and many other four star cars lack ESC and side airbags anyway, which will not help when Global NCAP updates its assessment protocol next year).

EDIT: I think the reason the 5-star rating applies only to later VINs is because of the addition of standard passenger SBR. If you regularly buckle up and own a 4-star Nexon, I think it's pretty safe to assume you're driving a 5-star car (technically, no, since all said and done it does not have the passenger SBR) since obviously, no structural changes were actually made. Global NCAP uses modifiers to indicate that the possibility of damage/injury could be worsened at higher speeds, higher loading or less overlap. It does not actually mean that there was high injury during the test, just that there is a risk of further injury. In the same way an unstable bodyshell modifier does not mean the structure collapsed during the test, a knee modifier does not mean the knees were badly injured during the test. Global NCAP simply observed dangerous structures behind the dashboard that could contact the knees, but Tata proved that they would not be so. Tata would have not sponsored the side impact test the first time anyway due to the ODB score not being met.

To sum up,
First test: 15.06-2.00=13.06 ODB, 0.50 driver SBR, 4 channel ABS, no side impact
Second test: 15.06 ODB, 1.00 SBR, 4 channel ABS, side impact conducted because 14/16 ODB score was passed

Quote:
Originally Posted by Vid6639 View Post
I wish we knew what was changed structurally vs the earlier model to get it the 5 star rating. Has to be something significant.

Current owners may not be too happy seeing that newer cars are safer than their cars.
It would be very interesting indeed to know where it was learnt that structural changes were made. It could be wrong on Tata's part to make a statement like this if they did, assuming what I've mentioned above about the knee modifier removal holds true.

Last edited by ron178 : 28th June 2021 at 22:32. Reason: Mentioned in post
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Old 28th June 2021, 23:15   #127
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Default Re: Tata Nexon: Global NCAPís first 5-Star Indian car

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Originally Posted by ron178 View Post
I'm glad someone finally pointed this out, because I had noticed it too. I have reason to believe the second frontal crash test for the Nexon never happened. If you observe the thumbnail images on the Global NCAP website, one seems to have brighter colour but on closer inspection of the video, it appears that the test is the same...........


The ODB test score did increase despite a second test not being conducted by Global NCAP. Observe the comments and the colour-coded dummies in both reports and you'll see that the ratings for all driver and passenger knees increased from orange to green. This is because the one-point variable contact modifier for each leg was removed by Global NCAP, presumably following a sled test conducted by Tata. (since knee modifiers are not a structural issue, they may be assessed without a destructive test...............

To sum up,
First test: 15.06-2.00=13.06 ODB, 0.50 driver SBR, 4 channel ABS, no side impact
Second test: 15.06 ODB, 1.00 SBR, 4 channel ABS, side impact conducted because 14/16 ODB score was passed
This is why I love this forum so much! You have my utmost respect, Sir. I could never have figured this out myself had you not presented this missing link. Thanks to you, my understanding of this particular crash is now more complete than ever before. I do not have words to sufficiently explain how elated I am by your findings and concise explanation. A big thank you, once again.

This explanation puts an end to my speculation. It perfectly aligns with your explanation, while also bringing clarity that chassis/structural changes were probably not required to achieve a 5-star rating. I was merely able to figure out the fact that ODB test was not conducted thanks to someone else's YouTube comment and whatever little I was able to decipher from the code on the vehicle, but your explanation perfectly explains why the ODB test wasn't reconducted. I had suspected Tata providing in house data to get the rating, but I wasn't sure of the nature of it. Your post very clearly delineates the provision of a sled test for removing knee modifiers. With that, I'm now reasonably sure that no structural changes were probably made. Your extra insight about the African Amaze was the icing on the cake.

I would like to thank you again for this beautifully written post. Thank you.

PS: @Nexusios1521, the post above, by BHPian ron178 is a far better answer to your query. Please ignore my earlier post.

EDIT:
Quote:
Originally Posted by ron178 View Post
It would be very interesting indeed to know where it was learnt that structural changes were made. It could be wrong on Tata's part to make a statement like this if they did, assuming what I've mentioned above about the knee modifier removal holds true.
I think that this is not something that Tata had claimed. It was more of a popular assumption back then because of the increase in score from 13.56 to 16.06, just like many of us had wrongly assumed that Tata sent a new vehicle for ODB test to get a 5-star rating. BHPian Vid6639 had also likely accepted the general notion about chassis/structural changes that was prevalent back then. I think he would be overjoyed to learn about these new findings.

Last edited by rpm : 28th June 2021 at 23:23.
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Old 28th June 2021, 23:19   #128
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Default Re: Tata Nexon: Global NCAPís first 5-Star Indian car

Quote:
Originally Posted by rpm View Post
Q: What's the big deal then? It's just some technical mumbo jumbo they might be using for Nexons in particular, right?
A: Well, here's the technical mumbo jumbo on the side impact test:
Full marks for decoding a sticker I never paid any attention to. It makes sense but then also leaves some repetition in case of xuv 3OO and XUV 5OO and not that the 7OO is also coming out. All the three would be called MXU

Weíll leave that problem to be solved by NCAPs themselves until we find out what the last digit means.

Could it be a designation for base-mid-top variant?
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Old 28th June 2021, 23:47   #129
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Default Re: Tata Nexon: Global NCAPís first 5-Star Indian car

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Full marks for decoding a sticker I never paid any attention to. It makes sense but then also leaves some repetition in case of xuv 3OO and XUV 5OO and now that the 7OO is also coming out. All the three would be called MXU

We’ll leave that problem to be solved by NCAPs themselves until we find out what the last digit means.

Could it be a designation for base-mid-top variant?
Thank you for your kind comment. To be fair to you, and myself, I too never paid any heed to these stickers, much less think of decoding them. Heck, I didn't even know they existed until that YouTube comment (my inspiration for the speculation) piqued my interest.

As of now, the last number is as mysterious to me as it is to you. The number 2 at the end is especially a very rare occurrence, even for cars that undergo both the ODB and MDB test. I guess it now becomes the collective responsibility of the forum to find out what this mystery number means.

I would agree with you that it is probably something related to the variants of the car. This is what I had in mind when writing my original post too, but without reasonable enough evidence to back me up, I left it out, because I wouldn't be able to reasonably explain which variants were signified by those numbers. The base-mid-top variant theory could work, except I have never seen the number 3 or 0 at the end. Then again, I have also not seen every single crash test video out there.

It would for sure be very interesting to see what code GNCAP uses for XUV 700. Guess that gives the two of us one more thing to look forward to other than the crash rating.

Last edited by rpm : 28th June 2021 at 23:54.
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Old 29th June 2021, 00:14   #130
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Default Re: Tata Nexon: Global NCAPís first 5-Star Indian car

Quote:
Originally Posted by rpm View Post
This is why I love this forum so much! You have my utmost respect, Sir. I could never have figured this out myself had you not presented this missing link. Thanks to you, my understanding of this particular crash is now more complete than ever before. I do not have words to sufficiently explain how elated I am by your findings and concise explanation. A big thank you, once again.
Thank you for your kind words, and thank you to you too for taking the initiative to point this out, since I was very skeptical of my findings.

Quote:
Originally Posted by rpm View Post
With that, I'm now reasonably sure that no structural changes were probably made.
I'm reasonably sure too, but not a hundred per-cent, since there is a slight, remote possibility that Tata modified the dashboard for the sled test and for cars with later VINs. I'm not sure of the protocol to be followed in this case (re-conducting the ODB test or accepting manufacturer verification data)

Quote:
Originally Posted by rpm View Post
I think that this is not something that Tata had claimed. It was more of a popular assumption back then because of the increase in score from 13.56 to 16.06, just like many of us had wrongly assumed that Tata sent a new vehicle for ODB test to get a 5-star rating. BHPian Vid6639 had also likely accepted the general notion about chassis/structural changes that was prevalent back then. I think he would be overjoyed to learn about these new findings.
Skip to 5:26 in this video and you'll realise this is not the case. Although I might be nitpicking here and this might have been an assumption by the Car&Bike host himself.


Quote:
Originally Posted by rpm View Post
As of now, the last number is as mysterious to me as it is to you. The number 2 at the end is especially a very rare occurrence, even for cars that undergo both the ODB and MDB test. I guess it now becomes the collective responsibility of the forum to find out what this mystery number means.
I'm really, really not sure of this one, but it looks like the number two is appended when a second test is performed on the same iteration of a car. Case in point:
The Hyundai i10, Volkswagen Polo and Maruti Alto without airbags both had two tests each performed on them - the UN R94 56 km/h test (whose footage was not revealed to the public except for the Nano) and the NCAP 64km/h test. If you observe the Tata Nano's thumbnail on the Global NCAP website, the UN R94 test has the number one (since it was the first test conducted) and all other cars (for which only NCAP 64 km/h results were displayed) have the number 2. However, mysteriously, the Nano's NCAP test has the suffix 1 too. Similarly, the Renault Kwid's third structural iteration had two tests conducted on it (one without an airbag and one with) - one is labelled as 1 and the other as 2. However this does not hold true for the Honda Mobilio, Tata Zest or Volkswagen Polo with airbags. Anyway, I don't think it's worth discussing in depth.
Quote:
Originally Posted by rpm View Post
It makes sense but then also leaves some repetition in case of xuv 3OO and XUV 5OO and not that the 7OO is also coming out. All the three would be called MXU...
...Could it be a designation for base-mid-top variant?
Pretty sure the guys at ADAC would have a tough time with the Hyundai Venue/Verna and the Honda Vezel, or the Škoda Karoq and Kamiq, Honda City and Civic, Ford Figo and Fiesta, all the Mazda 'MX-' and 'CX-'s, the Volvo 'XC-'s and, well, you get the picture. Thankfully they don't test scooters for India (the ADAC does test test motorcycles internally) or the Honda Accord and Activa would have a tough fight. They must have developed a workaround. As for variant designation, I don't think this is the case since cars like the Kia Seltos and Hyundai Grand i10 Nios which were not tested in their cheapest trims (basic safety specification was maintained, though) have the suffix 1.

Mods, sorry for going off-topic, I was trying to answer a question.

Last edited by ron178 : 29th June 2021 at 00:42.
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Old 29th June 2021, 03:58   #131
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.........Skip to 5:26 in this video and you'll realise this is not the case. Although I might be nitpicking here and this might have been an assumption by the Car&Bike host himself.
https://www.Youtube.com/watch?v=m3usR676rVI
I see your point. The first person they ask from Tata motors talks about understanding the knee and foot injury assessment criteria and finding a fix for that.
The second person he asks, however, could be interpreted to be talking about Tata's vision of conforming to crash norms in general. He seems to be talking about achieving crash norm compliance while the Nexon was still in the pre-production phase where they were trying to meet the weight, timeline and budget targets while developing a safe vehicle. The reason for this assumption is that the host says the following at 5:40ó it was positive to see that these changes were brought into production well before any test was even carried out.

Now this could either be the 2nd test or the 1st test, or both. If there were indeed some structural changes for the 2nd test, maybe they would be to incorporate side impact compliance? I so wish BHPian ram87pune could throw some light on this if his insider sources have any information regarding the same.
Quote:
I'm really, really not sure of this one, but it looks like the number two is appended when a second test is performed on the same iteration of a car. Case in point:
The Hyundai i10, Volkswagen Polo and Maruti Alto without airbags both had two tests each performed on them - the UN R94.......... However this does not hold true for the Honda Mobilio, Tata Zest or Volkswagen Polo with airbags. Anyway, I don't think it's worth discussing in depth.
Wow! I had no clue that UN R94 compliance was also checked for non airbag cars in the early days of GNCAP. With your insight on what the last digit could mean, and the plethora of examples you have given, I think I have been able to put together a makeshift theory. It is certainly not worth discussing in depth in the context of Nexon's NCAP rating since we already have a somewhat decent grasp on things even without it, however, it is a lot of fun trying to guess what it could actually mean, and I just can't resist putting my makeshift theory forward! I'm sorry!

So, as it turns out, the suffix 2 is indeed used when a second test is conducted on the same iteration of the car, but only if it arrived at the lab the same week as the first one!

Example: Kwid
Tata Nexon: Global NCAPís first 5-Star Indian car-screenshot_202106290217062.png
Tata Nexon: Global NCAPís first 5-Star Indian car-screenshot_202106290217002.png


But the Altroz isn't too happy to see my lackluster makeshift theory and stages a coup d'etat.
Tata Nexon: Global NCAPís first 5-Star Indian car-screenshot_202106280230342.png
Tata Nexon: Global NCAPís first 5-Star Indian car-screenshot_202106280231302.png

Does the Altroz succeed? Almost. Except. It doesn't. The mStallion is here to stall its plans, just like it stalled Altroz's plan of claiming the number 1 spot at GNCAP as the safest car in India.
Tata Nexon: Global NCAPís first 5-Star Indian car-screenshot_20210628031549.png
Tata Nexon: Global NCAPís first 5-Star Indian car-screenshot_20210628031616.png



So, ladies and gentlemen, I present to you, an even more makeshift version of my makeshift theory. It readsó The suffix 2 represents the 2nd car of the same iteration/make, on which another test is to be conducted, provided that the 2nd car not only arrives at the lab the same week as the first car, but also has a different color than the 1st car.

Quote:
As for variant designation, I don't think this is the case since cars like the Kia Seltos and Hyundai Grand i10 Nios which were not tested in their cheapest trims (basic safety specification was maintained, though) have the suffix 1.
I'm seriously in awe of your knowledge of crash tests. The reason it took me so long to respond to your post was because I couldn't completely wrap my head around the sheer amount of knowledge and data at display in your post. If you don't mind me asking, are you a crash test engineer? And how long have you been holding on to this speculation of yours (about Nexon)? How did you figure out which variants of the Seltos and i10 Nios were tested? I've never really been able to discern such things from the outside unless there is a distinct alloy design to differentiate them.

Also, I wasn't really expecting anyone to read my confused rambling on what was essentially a dead thread, but not only did a lot of people read it, I even got a reply which has my original post outclassed and outmatched in every aspect. Kudos to you and your automotive knowledge in the field of crash tests, Sir.
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Old 29th June 2021, 07:51   #132
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Default Re: Tata Nexon: Global NCAPís first 5-Star Indian car

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If there were indeed some structural changes for the 2nd test, maybe they would be to incorporate side impact compliance? I so wish BHPian ram87pune could throw some light on this if his insider sources have any information regarding the same.
This is something that cannot be ruled out. However we do have a reasonable explanation for the UN95 side impact test not being conducted the first time even if the car was ready for it. Besides, it would not have been so easy to make changes for side impact performance, and nevertheless, the UN95 test is not extremely hard to pass at all.

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Originally Posted by rpm View Post
Wow! I had no clue that UN R94 compliance was also checked for non airbag cars in the early days of GNCAP.
It was, and only for the first round of tests. Only the Figo passed because the driver dummy narrowly missed contacting the steering wheel. It was mentioned in older 2014 threads (Indian Nano, Alto, Figo, i10 & Polo FAIL Global NCAP Safety Test) on this forum when the crash test results were first out.

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Originally Posted by rpm View Post
So, as it turns out, the suffix 2 is indeed used when a second test is conducted on the same iteration of the car, but only if it arrived at the lab the same week as the first one!
We're going off-topic now and risk this thread being closed. Hence, this will hopefully be my last post about the mysterious number. Your theory seems perfectly sound, because the Nano's NCAP test was conducted much later in 2013 than the other tests, as it was showcased on TV by NDTV's Car&Bike who have a generally good relation with Global NCAP. However the XUV300 still keeps the mystery. A little trivia - I just noticed that before Euro NCAP introduced the Front Full Width Test in 2015, 'FO-' for Frontal Offset was printed by the ADAC before 'OD-'. If you want to perform further research about the number, though it's a waste of time in my opinion, do visit Latin NCAP and older Euro NCAP ratings since they use the same test laboratory at ADAC (Euro NCAP has others too).

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If you don't mind me asking, are you a crash test engineer? And how long have you been holding on to this speculation of yours (about Nexon)?
No, I'm still a student. To answer your second question, it's been about three months now.

So long, and we'll discuss the number when the next tests come out. Fingers crossed for another 5-star car.
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Old 29th June 2021, 13:19   #133
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Default Re: Tata Nexon: Global NCAPís first 5-Star Indian car

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However the XUV300 still keeps the mystery.
While casually going through the pictures I had uploaded, I just noticed that side impact test for XUV 300 is shown to be done at 50 km/h, while the Nexon and Altroz have been subjected to 64 km/h. Is the speed for the MDB described under UN 95 test flexible? I have seen Euro NCAP tests varying between 50 and 60 km/h too, but then, how is the speed for the MDB decided? Any thoughts?

Also, you missed this question from my earlier post.
Quote:
How did you figure out which variants of the Seltos and i10 Nios were tested? I've never really been able to discern such things from the outside unless there is a distinct alloy design to differentiate them.
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Old 29th June 2021, 13:59   #134
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Also, you missed this question from my earlier post.
I believe someone had mentioned this, either in the YouTube comment section or on this forum. However, in retrospect, I'm not too sure about my statement about the Seltos, though it holds true for the Nios because of the black window frames (the Era gets body-coloured frames) and the touchscreen infotainment system in the interior shots in the video. Some of the manufacturer-sponsored tests (The Tatas and the Mahindras) clearly have higher variants as evidenced by the presence of alloy wheels. Even the Nexon tested wasn't the base model (I believe the base trim of the Nexon doesn't get black window frames - I remember seeing one in the neighbourhood)

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While casually going through the pictures I had uploaded, I just noticed that side impact test for XUV 300 is shown to be done at 50 km/h, while the Nexon and Altroz have been subjected to 64 km/h.
I believe this is one of those occasional goofs by Global NCAP (after stating that the 2018 Swift had no 4-channel ABS and rating the first-gen i10's structure as stable and unstable in the same document). Euro NCAP themselves conducted 50km/h MDB side impact tests till 2020 (under the new 2020 protocol the side mobile deformable test is now conducted at 60 km/h) and the pole test has been conducted at 32 km/h for a while now (earlier 29km/h). I'm positive the minimum UN95 side impact test is conducted at 50km/h and not 64, this must have been a misprint. Although, the UN95 side impact protocol states that if the test is passed at a higher speed it can be considered to have been passed at 50km/h. The Nexon does not have side airbags so I doubt Global NCAP would test it at higher than 50km/h anyway, though the UN95 side impact is mainly a structural test.

The UN95 side impact protocol is available for public viewing here. You'll find what I mentioned in point 3 of Annex 4 of Page 22.

For reference, here is the section of the UNECE '95 side impact protocol regarding test speed. Hence there is a very, very remote possibility of the side impact test having been conducted at 64km/h though it's highly unlikely.
Quote:
3. Test speed
The mobile deformable barrier speed at the moment of impact shall be 50 Ī 1 km/h. This speed shall be stabilized at least 0.5 m before impact. Accuracy of measurement: 1 per cent. However, if the test was performed at a higher impact speed and the vehicle met the requirements, the test shall be considered satisfactory.
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The mStallion is here to stall its plans, just like it stalled Altroz's plan of claiming the number 1 spot at GNCAP as the safest car in India.
I believe I have discovered something interesting in the Global NCAP news report for the XUV300 that I did not notice before. Since the first two letters of the code already separates the offset frontal impact from the MDB side impact, I think it wouldn't be necessary to use a different number for the side impact. However:
Quote:
Global NCAP tested the side impact protection of the XUV300 under UN95 regulation, the car comfortably passed the requirements when tested on either passenger or driver side.
It appears that the XUV300 could have been tested on both, the driver and passenger side, and it can easily be observed in the test video that only the passenger side crash test has been revealed publicly. So it seems like the number 2 is used for the second side impact test on the XUV300 in the third week of 2020.
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Originally Posted by rpm View Post
However, the Altroz and Nexon were tested on the driver side only.
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Originally Posted by rpm View Post
Now this is very curious, considering even Euro NCAP introduced far-side impact assessment only last year (even then, their test is a sled test using the body-in-white, not a crash test, also, the dummies in the XUV300's test have been placed on the passenger side thus not qualifying for the name 'far-side' impact). So, my question is, why weren't the Altroz and Nexon tested on the passenger side, or rather, (and more importantly) why was the XUV300 even tested on the passenger side? I'm not complaining, because it proves that both sides offer equal protection, but I don't see the point in conducting a passenger side side impact test at all. At the very least, I'd like footage of the driver-side side-impact test.

Last edited by vb-san : 30th June 2021 at 09:15. Reason: Back-to-back posts merged. Thank you!
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Old 30th June 2021, 12:52   #135
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Default Re: Tata Nexon: Global NCAPís first 5-Star Indian car

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For reference, here is the section of the UNECE '95 side impact protocol regarding test speed. Hence there is a very, very remote possibility of the side impact test having been conducted at 64km/h though it's highly unlikely.
I would agree that this is more likely to be an error on GNCAP's part. This is solidified by looking at the side impact test of the Thar.

Tata Nexon: Global NCAPís first 5-Star Indian car-screenshot_20210630112407.png


Here, we see the driver side being struck, just like the Nexon and Altroz, yet the speed is 50 Km/h.

Quote:
I believe I have discovered something interesting in the Global NCAP news report for the XUV300 that I did not notice before. Since the first two letters of the code already separates the offset frontal impact from the MDB side impact, I think it wouldn't be necessary to use a different number for the side impact.
I too believe, that you have discovered something very interesting, Sir.

Quote:
It appears that the XUV300 could have been tested on both, the driver and passenger side, and it can easily be observed in the test video that only the passenger side crash test has been revealed publicly. So it seems like the number 2 is used for the second side impact test on the XUV300 in the third week of 2020.
I agree with your assessment. This makes the different color clause in my makeshift theory moot. I now propose the following with your newfound understanding of the mystery number: The suffix 2 is used for a 2nd car of the same iteration/make, on which a 2nd test of similar initial code (OD and MD in this case) is being conducted, provided that it arrived at the lab the same week as the first one.

Quote:
Now this is very curious, considering even Euro NCAP introduced far-side impact assessment only last year (even then, their test is a sled test using the body-in-white, not a crash test, also, the dummies in the XUV300's test have been placed on the passenger side thus not qualifying for the name 'far-side' impact). So, my question is, why weren't the Altroz and Nexon tested on the passenger side, or rather, (and more importantly) why was the XUV300 even tested on the passenger side? I'm not complaining, because it proves that both sides offer equal protection, but I don't see the point in conducting a passenger side side impact test at all. At the very least, I'd like footage of the driver-side side-impact test.
I agree with your assessment that the video shown for the side impact test, does not qualify as 'far-side' test because of the absence of dummies in seats adjacent to the side being struck by the MDB.

My best guess about the 'why' would be Mahindra itself. They were likely pushing for the safest in India crown, and might have gone a little overboard to get any and everything tested. This is evident in their proactive approach of getting ESC tested on both, the Thar and XUV 300. They even sponsored two new XUVs for the safer choice award, so that pedestrian protection and ESC could be tested.

Tata Nexon: Global NCAPís first 5-Star Indian car-screenshot_20210630115405.png

Do note from the code on this XUV that this one arrived in the 6th week, whereas the first three XUVs (for ODB and MDB) arrived in the 3rd week of 2020.

The difference here lies in the number of vehicles the manufacturer is willing to sponsor. Tata is willing to sponsor the minimum number of vehicles required for that particular rating, be it 4 or 5-star. Mind you, this isn't a bad thing at all in a country where the manufacturer with the highest market share outright refuses to send their vehicles for a test and calls GNCAP a self proclaimed party, while the manufacturer which is second on the sales chart is better at knowing its mistakes and keeping quiet instead of making ridiculous accusations and citing vague statistics to justify their mistake. Mahindra, on the other hand, is going the extra mile, and sponsoring vehicles for additional tests which make no difference to their rating. Case in point: the side impact test and ESC test for Thar.

One could argue that Mahindra's in-house crash data might have suggested a 5-star rating for the Thar and they sponsored the MDB vehicle either because of their incorrect data, or overconfidence. But that is simply not the case, because the ODB vehicle arrived at the lab in the 44th week of 2020, whereas the MDB vehicle arrived in the 46th week. For XUV, one could argue that they sponsored the additional vehicles for pedestrian protection and ESC because it was a requirement for the safer choice award (not sure if it actually is a requirement or not), but then, that doesn't explain them sponsoring the ESC test for the Thar.
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