RTV ROPS - beware

[Paystar]

I'll just say ... those pics don't exactly make me want to rush out and buy a Kubota.

Lets see how your Kioti or any other brand fares after MULTIPLE barrel rolls, LOL

It's a ROLL OVER protection. Not a CATOSTOPHY protector.

 

[PuffyC]

It's a ROLL OVER protection. Not a CATOSTOPHY protector.

In this case it was neither.

 

[WilliamBos]

Lets see how your Kioti or any other brand fares after MULTIPLE barrel rolls, LOL

It's a ROLL OVER protection. Not a CATOSTOPHY protector.

Yeah, the Kioti would not of survived either.

 

[wawajake]

The way I read "between the lines" about the accident is......I rolled my modified RTV off basically a cliff , and its open cab was destroyed, ....I now want to blame Kubota for it not surviving . (Of note though, surprisingly it started and drove still after multiple rollover)

 

[bdog]

It wasn’t a cliff. The trail it was onwe created with a dozer last week. The Kubota drove down it two times before flipping on the third. The slope wasn’t straight down it had a slight sideways tilt to it. I think what happened is a front tire fell into a small hole and the rear end starting coming around and that was it.

I certainly don’t think the machine should escape something like this unscathed but I would expect a rops to hold up better. The driver got up and worked the rest of the day. If he would have been belted in I bet he would still be in the hospital or dead.

Attached are some more pictures. The roof tore off some more due to the wind in the drive home.

 

[RoyJackson]

It wasn’t a cliff. The trail it was onwe created with a dozer last week. The Kubota drove down it two times before flipping on the third. The slope wasn’t straight down it had a slight sideways tilt to it. I think what happened is a front tire fell into a small hole and the rear end starting coming around and that was it.

I certainly don’t think the machine should escape something like this unscathed but I would expect a rops to hold up better. The driver got up and worked the rest of the day. If he would have been belted in I bet he would still be in the hospital or dead.

Attached are some more pictures. The roof tore off some more due to the wind in the drive home.

I'm no metallurgist, but it sure looks the wall thickness on the ROPS tubing is thin (less the 1/8th)
It looks like the wall thickness on my Gator's ROPS is around 3/16" (.187") thick

 

[bdog]

I wouldn’t really call it modified either. It had a sun shade canopy and the tweels both were added by the dealer at the time of purchase. Modified to me would be if we had a lift kit or welded something on to or drilled holes in the rops. We did not. The canopy was clamped on.

 

[bdog]

It is very thin. To me it looks about like 14ga.

 

[ruffdog]

Different manufacturers follow different certifications or maybe none at all. It seems the RTV meets the OSHA and SAE standards while other's don't.

https://www.federalregister.gov/doc...rd-for-recreational-off-highway-vehicles-rovs

https://www.kubotausa.com/docs/defa...pdfs/rtvxseriescompspdf.pdf?sfvrsn=59c30ffc_2

 

[ruffdog]

...also, the standards for tractors are different than the ones for UTVs.

 

[Jchonline]

It wasn’t a cliff. The trail it was onwe created with a dozer last week. The Kubota drove down it two times before flipping on the third. The slope wasn’t straight down it had a slight sideways tilt to it. I think what happened is a front tire fell into a small hole and the rear end starting coming around and that was it.

I certainly don’t think the machine should escape something like this unscathed but I would expect a rops to hold up better. The driver got up and worked the rest of the day. If he would have been belted in I bet he would still be in the hospital or dead.

Attached are some more pictures. The roof tore off some more due to the wind in the drive home.

That is some thin looking steel….

 

[John0829]

IMHO that ROPS failed big time and Kubota needs to know. A ROPS is suppose to be designed to support he ENTIRE weight of the machine it installed on in a roll over for a reason and from what I understand from the description it was an easy low speed roll and that ROPS would definitely not have protected the passenger.

 

[KiotiKowboy]

IMHO that ROPS failed big time and Kubota needs to know. A ROPS is suppose to be designed to support he ENTIRE weight of the machine it installed on in a roll over for a reason and from what I understand from the description it was an easy low speed roll and that ROPS would definitely not have protected the passenger.

I agree - however, I am not an engineer .... BUT .... I did stay in a Holiday Inn once!

 

[RickB]

I agree - however, I am not an engineer .... BUT .... I did stay in a Holiday Inn once!

Us not being engineers is exactly why I and others think Kubota needs to see this RTV.

 

[s219]

I wouldn’t really call it modified either. It had a sun shade canopy and the tweels both were added by the dealer at the time of purchase. Modified to me would be if we had a lift kit or welded something on to or drilled holes in the rops. We did not. The canopy was clamped on.

Do you know which direction it rolled in, passenger side downhill perhaps?

My previous work in accident investigations is limited to aircraft, so this is a bit out of my realm. But there are some interesting clues here that are jumping out at me. The roof panel is punched in fairly uniformly in the middle, so at least one of the rolls happened with an intact ROPS bearing weight evenly across the roof. Then in a subsequent roll, it looks like the passenger front pillar broke near the upper weld where there is a gusset, and that in turn led to failure of the passenger rear pillar. The driver's side seems much more intact in comparison.

I would not be surprised if the ROPS is designed for limited dynamic loading, meaning it could probably take a couple simple rolls, but if this RTV rolled 4+ times on the way to the bottom of a big hill, that is a lot of speed/energy building up. It's clear the lower frame bent too, and that tells us this wasn't a gentle flop. So it may have been beyond what the ROPS is meant to handle.

The other thing that could be a factor is that aluminum roof. Aftermarket I presume? It is in remarkably good shape considering what happened. Aluminum plate can handle very high skin loads, and that could change the structural characteristics of the ROPS under load. If the ROPS was intended to flex or twist in a certain way but the roof panel stiffened the upper section, for example, that could concentrate and transfer the load to a weaker member or joint that is not meant to handle it.

If you know the height and angle of the slope, we can make some simple estimates of the energy and loads.

 

[ruffdog]

Kubota is only going to say the crash exceeded the limits of OHSA 1928.53 and you were lucky no one got hurt. People still die when they wear seat belts, with airbags, helmets, and all the other safety equipment when the forces are large.

With this RTV, the force was so strong it twisted and bent the frame too. How far it fell before it landed on the top right corner multiplies the weight of the object. The induced force may be measured in the tons.

1928.53 - Protective enclosures for wheel-type agricultural tractors -- test procedures and performance requirements. | Occupational Safety and Health Administration

 

[bdog]

From where the RTV started sliding to where it stopped was approximately 200' horizontally and a drop of 90' -24 degrees or 45% slope.

I was looking at it in more detail and the frame is cracked on both sides. Attached are pictures.

I am in no way trying to bash on the RTVs. I own five and I will be buying another to replace this one. I just always thought of a ROPS as a place to survive a nuclear blast. It surprised me how thin and weak it appears to be.

 

[Paystar]

I don't have to be an engineer to know that thing took a bigger fall than what it is designed to withstand.

But hey, lets blame the manufacturer. You should sue too like everyone else does so that prices can inflate even higher. With enough litigation you might even be able to get them to put bigger cages, slow them down even more, put airbags, abs brakes, collision mitigation, stability control, traction control, and make you sign a waver to buy one. Oh heck, lets just ban all motorized vehicles, because for every machine out there, there is an idiot that can hurt himself on it, LOL

 

[bdog]

I don't have to be an engineer to know that thing took a bigger fall than what it is designed to withstand.

But hey, lets blame the manufacturer. You should sue too like everyone else does so that prices can inflate even higher. With enough litigation you might even be able to get them to put bigger cages, slow them down even more, put airbags, abs brakes, collision mitigation, stability control, traction control, and make you sign a waver to buy one. Oh heck, lets just ban all motorized vehicles, because for every machine out there, there is an idiot that can hurt himself on it, LOL

That is not at all my intention. I am not asking from a thing from Kubota. I called my dealer and asked him to find me a new one. I honestly just thought the rops was stronger than it is. That is all. We rolled it down a hill. Totally our fault. The driver was uninjured and was able to work the remainder of the day. That is a great thing.

Everyone has to make their own decisions but from my perspective I think one is better off jumping out of the RTV than staying buckled in and riding it out if facing a rollover like this.

 

[etpm]

I don't have to be an engineer to know that thing took a bigger fall than what it is designed to withstand.

But hey, lets blame the manufacturer. You should sue too like everyone else does so that prices can inflate even higher. With enough litigation you might even be able to get them to put bigger cages, slow them down even more, put airbags, abs brakes, collision mitigation, stability control, traction control, and make you sign a waver to buy one. Oh heck, lets just ban all motorized vehicles, because for every machine out there, there is an idiot that can hurt himself on it, LOL

Why the straw man argument?
Eric