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Old 5th December 2013, 17:42   #16
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Default Re: Thar Hard Top, how safe in a roll over?

Sudarshan,
As rightly pointed out, there is no alternative to a six point roll cage, HT or ST.

Tejas,
An HT definitely offers more protection than a ST, though maybe not life saving.


Go Slow,
Though a HT may take the first blow better than a ST but it is no safety without a RC, the best safeguard is an RC, still lives were lost in spite of RC's.
[/quote]

Quote:
Originally Posted by Tejas@perioimpl View Post
Somehow i guessed that some pics like this proving the FRP is strong would come out after this thread was started.

I haven't seen how the crash happened and nor am i a crash forensic investigator to comment on it.

All i'd like to say is that let this thread not put a wrong notion in people that the FRP is a safe alternative to a roll cage. I know you are not saying that but people should not interpret it as such.
Tejas,

How intuitive you are!

Yes, I understand that you are not the expert in crash investigation 'here'. Neither have I seen the crash happen, what has been stated by me is an first hand account of the persons involved.

After repeating myself on different posts on this thread and other, about the importance of an RC and that an HT is not an alternative to it, still you misinterpret? Is it deliberate?

Quote:
Originally Posted by ex670c View Post
I don't think the vehicle had a triple roll otherwise the B-Pillar and the HT components would have been totally crushed.

Also looks like the roll-over was caused by impact to the Left Fender/Lower Arm/IFS. Maybe an overtaking move gone wrong.

Which lifted the vehicle and dropped it onto the divider crushing the A-Pillar and Deforming the HT.

Had the vehicle rolled across the highway; considering the are driving in their lane

1) A triple roll-over will take at least 6ft+7ft+6ft+7ft+6ft+7ft+6ft+7ft+6ft +7ft+6ft+7ft+6ft = 84ft from start to finish provided the vehicle executes a perfect roll, and does not bounce skewering my calculation.

6ft = Width of the Vehicle
7ft = Height of the vehicle

In that case it will land in the opposing lane.

2) The Glass and Debris will be strewn across the width of the highway.

3) From the pictures it does not look like the HT Roof bore the brunt of the impact

To Say the a HARDTOP has some role in saving lives is purely misleading the general public.


It is looking for a silver lining which can be misinterpreted as Marketing Ploy.

However for the benefit of the off-roading public I hope FMSCI & FIA Approve of the Hyderabad HT as an alternate to the 6pt Roll-Cage
Arka
Arka,

All those equations and accident dynamics for nothing, a waste!

Your assumption and analysis for the cause of the accident was most inaccurate and a far cry from what the actual cause was.

If I had not posted the pics you all would not agree to even a single roll over, leave alone three. Now you see why the pics were necessary?

For the ones who have missed out, I have highlighted my own earlier quotes in Bold.

Reg. the FMSCI & FIA bit from you, that is "misleading" than any of my posts. Why this uncalled for sarcasm? It does not happen among men.

Simple English Arka, it was from my quote from the deleted post, "Without a roll cage this HT did prove something, yet it cannot be claimed that it saved lives." highlighted in bold above for you. Now compare this with your bold and underlined reply.

"Marketing ploy": Where is the need?

You definitely have a right and are entitled to your own interpretation.
Regards,

Last edited by GTO : 8th December 2013 at 12:03. Reason: PM coming up
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Old 5th December 2013, 20:18   #17
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Thumbs down Re: Thar Hard Top, how safe in a roll over?

Ahem, seems a lot has happened recently.

I think the OP is genuinely trying to put his point and draw out useful information from it.

I don't understand why people here jump in when they sense a scapegoat around. Don't you guys make mistakes? You have to give it to them for developing a HT with whatever knowledge / expertise they had. They may not have the best know-how about vehicle dynamics, but who among those present here has? Give them time, let them speak, the readers are mature and smart enough to make valid interpretations out of it.

Pulling legs, taunting, finger pointing on a forum like this, yields nothing other than bad blood. It's high time people here start appreciating work, no matter how simple or miniscule it is. For those, who have not been exposed to manufacturing (leave alone automobiles for that matter), will never understand what goes behind getting a product in to production (energy, time, money, sweat, blood). Try manufacturing a simple M4 hex nut for an example, then we will speak.

Sorry for the rant, but I see discussions moving in wrong directions. In stead of focusing on the topic, the focus these days is on individuals. Time for some change !

Now can someone post a pic of the accident ?

Spike

PS- I am in no way interested with the commercial side of HT development, that is something which least interests me.

Last edited by SPIKE ARRESTOR : 5th December 2013 at 20:45. Reason: typo
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Old 5th December 2013, 22:45   #18
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Default Re: Thar Hard Top, how safe in a roll over?

Quote:
Originally Posted by fazalaliadil View Post

Yes, I understand that you are not the expert in crash investigation 'here'. Neither have I seen the crash happen, what has been stated by me is an first hand account of the persons involved.


Arka,

All those equations and accident dynamics for nothing, a waste!

Your assumption and analysis for the cause of the accident was most inaccurate and a far cry from what the actual cause was.

If I had not posted the pics you all would not agree to even a single roll over, leave alone three. Now you see why the pics were necessary?

For the ones who have missed out, I have highlighted my own earlier quotes in Bold.

Reg. the FMSCI & FIA bit from you, that is "misleading" than any of my posts. Why this uncalled for sarcasm? It does not happen among men.
Hi Fazal,

Since you were not present at the accident, and were not an eyewitness, your interpretation can be considered speculative or exaggerated, or may be the crash survivors over played the accident, to make it more dramatic.

wrt to my forensic analysis it maybe totally off the mark.

But please make an educated guess, who much lateral and forward distance will it take for a vehicle to roll 3 times (1 roll is 360 degrees) and then land on its roof.

I have seen a MM540DP roll and come back on its wheels on sand and the resulting damage, I have the photo sequence of the roll-over.

So I'm making this guess.

What is the need to start this thread and then, highlight the Hyderabad HT, and speculate its role in an accident?

This seems to be a case of Any publicity is good publicity.

Regards,

Arka

Last edited by moralfibre : 6th December 2013 at 15:37. Reason: Fixing quote tag
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Old 6th December 2013, 09:00   #19
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Exclamation Re: Thar Hard Top, how safe in a roll over?

Apart from the debate of promotion of some particular make of HT or any particular accident.

Here are my thoughts over all this. Thinking Afresh

Quote:
Originally Posted by fazalaliadil View Post
Dear Members,

In an accident or a rollover with or without a roll cage, how important a role does a 'Hard Top' play in saving the driver/ passengers of the vehicle from minor to severe injuries, as compared to a soft top Thar?
Now, why only a Thar & which particular model ? CRDe (high speed) or DI (like normal Jeep) . Why not other Jeeps & 4x4s ?

If it means only CRDe, are we assuming high speed topples only ? Dont they topple off road at low speed ? And if they too topple at low speeds so does the other 4x4 vehicles, then why you point at Thar only ?

Its confusing, Include every 4x4 travelling in any terrain. HT gypsy, Gurkha etc.

Quote:
Would a FRP hard top survive a roll over and what would be its general condition after?
This is a very general question, there will be lots of qualities & materials & methods of making it.

According to a very senior person in vehicle R&D, its sort of prototype material, not to be relied upon much.

Then comes the Issue of standardization. What ever is currently made available in the market, does it have any rating?

Can we talk like this, for example an A rated top vs B rated top ? every maker will say mine is the best.

So in short from where we start the discussion? If at all we take any particular top for discussion again what kind of certification it has ?

All these tops, are they certified by some institution like ARAI , ISI etc ?

The discussion itself is vague.

But from experiences from the past & other observations, All I can say is its not reliable. It may protect from elements up to a certain level compared to soft top .

Its not a helmet if anyone wants to depend on it, it breaks & cracks & shatters on impact. The joints come off badly & not to mention its a total loss affair compared to metal. Its very difficult to cure even minor cracks.

I will any day depend on a locally made metal body for the purpose of accident, than any locally made Non Standardized or Non Certified FRP hard top



Quote:
Your valuable inputs could help in saving lives by improving the design.
Regards,
To be frank, who is going to get benefited with such inputs or is this a general statement ? And if at all they want any opinion, can we know/share what kind of test these people have made first & what kind of data they have ?

Sudarshan
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Old 6th December 2013, 09:18   #20
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Default Re: Thar Hard Top, how safe in a roll over?

Quote:
Originally Posted by ex670c View Post
But please make an educated guess, who much lateral and forward distance will it take for a vehicle to roll 3 times (1 roll is 360 degrees) and then land on its roof.

So I'm making this guess.

What is the need to start this thread and then, highlight the Hyderabad HT, and speculate its role in an accident?
Hi Arka,

Frankly, I am not empowered enough to make those calculations by observing 2D images of the vehicle involved. You too are "guessing" the same. A single roll too would be questioned and doubted in the absence of the pics.
Secondly, I have no reason to doubt a persons first hand account of the accident nor a reason to exaggerate the incident.

Finally wrt starting the thread, In my first reply I have mentioned the reason.
When a HT was involved in a real time situation, incidentally the HHT, what else would I post or analyze if not this one?

Read again from the start, the role of the HHT has not been emphasized or highlighted here, as it is being made out to be neither is it being compared to any other HT. The very crux here is HT vs ST and its limited safety (not versus a RC).

It would be speculative had the HT not been in the situation, it was and is open to each person's interpretation.
Regards,

Last edited by fazalaliadil : 6th December 2013 at 09:35.
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Old 6th December 2013, 10:34   #21
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Default Re: Thar Hard Top, how safe in a roll over?

Hello All

I found this thread useful. The content can be read in different ways...

As mentioned earlier, my Thar is at Bimbra workshop for a FRP HT fittment. I have had a chat with him since reading this thread and now understand what can be expected in event of a topple. Earlier, maybe I would not have asked the relevant questions.

My plans of installing a RC comes from the perspective of safety and has nothing to do with having a HT. Only decision that will drive a RC installation in realtion to the HT will be wether to get and external or an internal RC.
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Old 6th December 2013, 11:00   #22
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Default Re: Thar Hard Top, how safe in a roll over?

Internal or external roll cage or bars are only guarantee for any protection. FRP hardtop is just to give protection for wind or dust at best.
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Old 6th December 2013, 11:45   #23
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Default Re: Thar Hard Top, how safe in a roll over?

....and as a aside. Recently I was stopped by Chandigarh police who deemed that hardtop was a modification not reflected in the RC of the vehicle and so I need to be challaned!!
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Old 6th December 2013, 12:14   #24
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Default Re: Thar Hard Top, how safe in a roll over?

Quote:
Originally Posted by Sudarshan View Post
Here are my thoughts over all this. Thinking Afresh

Now, why only a Thar & which particular model ? CRDe (high speed) or DI (like normal Jeep) . Why not other Jeeps & 4x4s ?

If it means only CRDe, are we assuming high speed topples only ? Dont they topple off road at low speed ? And if they too topple at low speeds so does the other 4x4 vehicles, then why you point at Thar only ?

Its confusing, Include every 4x4 travelling in any terrain. HT gypsy, Gurkha etc.

This is a very general question, there will be lots of qualities & materials & methods of making it.

According to a very senior person in vehicle R&D, its sort of prototype material, not to be relied upon much.

Then comes the Issue of standardization. What ever is currently made available in the market, does it have any rating?

Can we talk like this, for example an A rated top vs B rated top ? every maker will say mine is the best.

So in short from where we start the discussion? If at all we take any particular top for discussion again what kind of certification it has ?

All these tops, are they certified by some institution like ARAI , ISI etc ?

The discussion itself is vague.

But from experiences from the past & other observations, All I can say is its not reliable. It may protect from elements up to a certain level compared to soft top .

Its not a helmet if anyone wants to depend on it, it breaks & cracks & shatters on impact. The joints come off badly & not to mention its a total loss affair compared to metal. Its very difficult to cure even minor cracks.

I will any day depend on a locally made metal body for the purpose of accident, than any locally made Non Standardized or Non Certified FRP hard top

To be frank, who is going to get benefited with such inputs or is this a general statement ? And if at all they want any opinion, can we know/share what kind of test these people have made first & what kind of data they have ?
Sudarshan,

Thank you for the rethink and seeing this thread in a right perspective.

You are correct, it should be addressed not only to Thar but all soft top vehicles. The reason for doing so was due to the specific HT production for Thar's, mostly.

Like the senior person has stated, it cannot and should be relied upon when it comes to accidents, but at the same time an HT is marginally safer compared to a soft top (but not without an RC).

The primary reason that a owner opts for a HT is not accidental safety but the advantage of a lockable cabin, dust, sound and heat proofing.
This should be remembered and a RC should be the principal safety fitment, even if it is not an off road vehicle. 540/50 share almost the same design dynamics as the Thar but Thar's are more vulnerable to major accidents due to their top speed exceeding 140kmph and a very high CG (on lifts and bigger after market tyres).

Even a metal body or top as you have mentioned should not be taken as a safer option in an accident over FRP, as the same is again non standardized or non certified. "I will any day depend on a locally made metal body for the purpose of accident" as you have mentioned is the same as depending on a FRP HT.
Bottom line is if you are looking for safety, there is no alternative for a proper six point Roll Cage, period.

The essence of this thread is not to pit or compare one HT manufacturer to another but for all them to raise their safety standards.
In the absence of any rating authority for the design and production of a HT, from the days of Roplas, it is entirely upon the manufacturer to at least design and ensure that his HT does not crumple, collapse, tear, shatter, come off its fasteners or break and it should provide better safety than a ST.

Who will benefit form the discussion? The end customer should.
Regards,
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Old 6th December 2013, 15:44   #25
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Default Re: Thar Hard Top, how safe in a roll over?

Quote:
Originally Posted by sudev View Post
....and as a aside. Recently I was stopped by Chandigarh police who deemed that hardtop was a modification not reflected in the RC of the vehicle and so I need to be challaned!!
OMG Now this is twist in the story. Thanks for sharing this.

Quote:
Originally Posted by red herring View Post
My HT has developed some cracks where it meets the rear gate - so if it cannot stand the impact of a door slamming hard, I doubt it will be able to withstand a roll over.
Yes, from my little research on HTs available in market, this is common problem everywhere may be because of 2 different type of material contact.

As all the respected seniors members of the forum are on this thread I would like to take opportunity to ask some questions. I would expect a firm answer with technical backing rather than guess.

1. Six point roll cage:
- Are there any standard guidelines to make it.
- How it should be enforced on the body/chassis for better protection.
- Internal or external roll cage.
- If my Jeep is all purpose vehicle, is the 6 point roll cage is legal on public road/city roads.

2. Hard top should be made out of sheet metal or FRP? Why?
- Does HT weight (added weight because of HT) matter in over all vehicle dynamics as it is after market product.
- My Thar's RC do not have soft top/hard top embossed on it, is there any RTO policy to emboss after market HT on RC?
- I have seen some trucks with FRP cabin, how safe are they.

3. If I am using stock Thar with just 2 front seat occupant, how safe is it in case of roll over?

Hope my points are self explanatory.

Thanks,
Vishal.
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Old 6th December 2013, 16:07   #26
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Default Re: Thar Hard Top, how safe in a roll over?

Coming from chandigarh I'm not surprised! I have been stopped for driving a two wheeler with sandals and challaned for not carrying a first aid kit in my car!!! I haven't been stopped in Mumbai in the last 1/2 year for my HT. I guess Chandigarh is an exception with such rules! ( though I'm happy they have them...its keeps the 'city beautiful' beautiful )
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Old 6th December 2013, 16:52   #27
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Default Re: Thar Hard Top, how safe in a roll over?

Quote:
Originally Posted by Sudarshan View Post
According to a very senior person in vehicle R&D, its sort of prototype material, not to be relied upon much.

ETC ETC

I will any day depend on a locally made metal body for the purpose of accident, than any locally made Non Standardized or Non Certified FRP hard top
Assuming that a locally built metal body is automatically better than a non-certified FRP top is wrong - unless that locally built metal body is certified.

FRP is definitely not a 'prototype' material and is known to be able to take much more impact than steel if manufactured properly.

Regardless of material used for the roof - soft, hard FRP or hard steel, there is no way any of them can provide the protection that a roll cage can.
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Old 6th December 2013, 17:22   #28
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Default Re: Thar Hard Top, how safe in a roll over?

Quote:
Originally Posted by Thar4x4 View Post

As all the respected seniors members of the forum are on this thread I would like to take opportunity to ask some questions. I would expect a firm answer with technical backing rather than guess.
As my profile tag shows, I am a senior member here (& respected for various reasons) , so answering with my level best.

Quote:
1. Six point roll cage:
- Are there any standard guidelines to make it.
I dont know it yet, but this has to change with vehicle to vehicle
Quote:
- How it should be enforced on the body/chassis for better protection.
In short, the mountings need to be connected to chassis or as close to chassis members preferably on lower tub
Quote:
- Internal or external roll cage.
Internal,unless the space is cramped
Quote:
- If my Jeep is all purpose vehicle, is the 6 point roll cage is legal on public road/city roads.
Very difficult question, but add ons / accessories which do not exceed 2% of vehicle weight are permitted (please check MV law on this)

Quote:
2. Hard top should be made out of sheet metal or FRP? Why?
Its a personal choice. Depending upon workmanship.
Quote:
- Does HT weight (added weight because of HT) matter in over all vehicle dynamics as it is after market product.
It may cause more body roll, certainly the CG (Center of Gravity) will be raised as the vehicle becoming top heavy.
Quote:
- My Thar's RC do not have soft top/hard top embossed on it, is there any RTO policy to emboss after market HT on RC?
I have not come across any legal provision regarding this. But the RTO will certainly need a certified body builder to do it, as it happens with other vehicles that come as chassis from the factory, who is a certified Jeep body builder around ? Need to find it.
Quote:
- I have seen some trucks with FRP cabin, how safe are they.
I dont know about this

Quote:
3. If I am using stock Thar with just 2 front seat occupant, how safe is it in case of roll over?
A roll cage will make a difference, still there is NO certainty. Only better than this or that.


Quote:
Originally Posted by Steeroid View Post
Assuming that a locally built metal body is automatically better than a non-certified FRP top is wrong - unless that locally built metal body is certified.
.
That is "MY" personal preference Sir & its based on personal experience.

With my hand built metal body, which apparently is very crude & sure wont pass any engineering test (though it has M&M approval "seal" on it & seeing that, a very senior friend of mine laughed quite a bit ), I survived a horrible crash in 1997 & another bro in law of mine nearly lost it with a Roplas body --- Sum total = you are never sure .

Sudarshan

Last edited by Sudarshan : 6th December 2013 at 17:36.
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Old 6th December 2013, 22:43   #29
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Default Re: Thar Hard Top, how safe in a roll over?

Hi Sudarshan:

Roplas is a single peice top. They have added the ridges to give some strength, but without the sub frame it cannot be held erect. A well made FRP top can be made as strong, if not stronger than locally tinkered hard tops.
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Old 6th December 2013, 22:49   #30
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Default Re: Thar Hard Top, how safe in a roll over?

Quote:
Originally Posted by sudev View Post
....and as a aside. Recently I was stopped by Chandigarh police who deemed that hardtop was a modification not reflected in the RC of the vehicle and so I need to be challaned!!
Ouch;what was the registration number of the vehicle sir?
Quite a few Modded Thars and Jeeps with HT's and what not,roam around the city beautiful,its just that the cops mess around more with outstation vehicles.
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