VOLVO TOWING 5TH DURING ROLLOVER

[NoDirectionHome]

A couple of observations: 
None of the discussed hitches provide any front (pin) roll stiffness.  That is a de-stabilizing feature.  They all seem to provide ~ +/-  30 degrees of roll freedom.  The ET & Hensley i believe are 4 bar linked so would be hard pressed to provide much roll resistance after the ~30 degrees are taken up.  The ComfortRide perhaps some.
     The agility and maneuverability of a combination of short wheelbase along with long rear overhang ratio create more movement per angle of steer and are also de-stabilizing elements.  
     In my judgement, this was a chain of events accident as are so many others.  Each owners needs and decisions only come to light at the edges of the envelope.  I've often read; "pulls great", "never a problem",  "don't even know the trailer's there".  No of course not... till you reach the end of the envelope.  Just ask NeverEasy.
     

[ALLOY]

17 minutes ago, NoDirectionHome said:

     The agility and maneuverability of a combination of short wheelbase along with long rear overhang ratio create more movement per angle of steer and are also de-stabilizing elements.  

     

I've been thinking how much the factor of the overhang played a part. Added to the overhang the force is introduced much higher up than say a bumper pull with a similar overhang. 

 

 

 

 

 

[Dollytrolley]

Not sure the "simple-math" in the link below will help much , however some of the text in the link might explain some of the factors that lead from stable-state into unstable.......

 

https://en.wikipedia.org/wiki/Directional_stability

 

Accident reconstruction with only a dash cam shot is like send me to the casino to buy you a winning mega-bucks ticket........good luck.

 

Having been abused by too many accident reconstruction geeks over a few decade it seems that they always want to start at the very beginning of the accident-chain whilst the large crowd of "onlookers" are swarming around the final resting place of the wreckage.......

 

Wreck geeks would be measuring scrape marks where the  rim hit the pavement and various tire marks as well as MANY clues that are missing in the thread........

 

Not sure how many Dr Peppers Big5er would kill documenting this accident site but I am sure that a six-pack would hit the dust.....

 

As far as the hitch.........hummm.......what are the "design-loads for a trailer hitched but cycling 180 degrees out of envelope???

 

Drive on...........(Fortunate no was injured.........)

[NoDirectionHome]

Quote

Not sure how many Dr Peppers Big5er would kill documenting this accident site

Overtime or straight time?

[VegasFlyer]

3 hours ago, ALLOY said:

I've been thinking how much the factor of the overhang played a part. Added to the overhang the force is introduced much higher up than say a bumper pull with a similar overhang. 

 

 

 

 

 

With the video showing the rear of the truck being in a stable path, the overhang would have no effect whatsoever.  In fact the video should be a good demonstration to the folks out there who believe that placing the hitch on a stinger is blasphemous.

To your point, if the video were to show the rear of the truck swerving back and forth, there would have been a significant amplification of lateral side forces.  Without the swerving, the stinger would have no effect whatsoever.

To those declaring that the hitch failed, I would submit that you are reaching a complicated assertion with very little data.  Those pictures, while ugly, are nowhere enough to tell the whole story or reach a conclusion.

[NoDirectionHome]

The video shows the truck swerving right / left hard at speed.  Be assured the rear did the opposite at the ratio of the wheelbase to the distance from pin to rear axle.  Geometry.

[VegasFlyer]

2 hours ago, NoDirectionHome said:

The video shows the truck swerving right / left hard at speed.  Be assured the rear did the opposite at the ratio of the wheelbase to the distance from pin to rear axle.  Geometry.

With a truck that long, if there would have been hard swerving, the truck would have been going through several lanes.  Given the narrower construction lanes, that truck did not appear to move that much.  Now the trailer is a different story.

If that had been a one ton pickup, you would expect the travel of the truck to be significantly more lane travel, most likely into the oncoming lanes.

[Dollytrolley]

 

2 hours ago, VegasFlyer said:

With the video showing the rear of the truck being in a stable path, the overhang would have no effect whatsoever.  In fact the video should be a good demonstration to the folks out there who believe that placing the hitch on a stinger is blasphemous.

To your point, if the video were to show the rear of the truck swerving back and forth, there would have been a significant amplification of lateral side forces.

To those declaring that the hitch failed, I would submit that you are reaching a complicated assertion with very little data.  Those pictures, while ugly, are no where enough to tell the whole story or reach a conclusion.

 

2 hours ago, NoDirectionHome said:

The video shows the truck swerving right / left hard at speed.  Be assured the rear did the opposite at the ratio of the wheelbase to the distance from pin to rear axle.  Geometry.

At first glance one might think that V F and Nodirect might have opposing views (and they might) ......However.......they may be somewhat in agreement and not realize it so.........

 

So......here is my postulation (my-BIG-word-of-the-day)......The Volvo being a ........Non-Constrained body but engineered to be fairly stable within its design limits WILL naturally have osculation(s) when it's steady state dynamics are "excited" (upset) and so IF the "upset" is within the "positive-restoration-profile" of the vehicle the osculation(s) will tend to diminish until the the vehicle will become dynamically-stable once again........

 

So......Nodirect correctly observed that the Volvo did indeed be come "upset" and John likewise observed the Volvo did become stable after being "upset" so it was within it's positive-stability profile.....(this time).....

 

Now that I am using my BIG-word........why not over-use it and "Postulate" that the trailer likely became unstable and entered into it's ....."Divergent........instability-profile" and the accident was a forgone conclusion.....once stability becomes divergent it only become stable once the wreak come to rest.

 

The primer on stability that I previously posted at the end of the lesson mentions the role that suspension that plays in vehicle dynamics and the RV sector as a whole has grim suspension so the threshold to "divergent-stability" tends to be very low......too low......

 

As far as the hitch damage John brings up a good point......and if the hitch was NOT the INITIAL failure point then it was likely the one of many highly stressed joints that could and would fail once the design limits are exceeded when the trailer rolled over......

 

Drive on..........(aint BIG-words.......neat)

[Ronbo]

I would much rather the hitch sustain the damage and save the truck. I also believe my ET Junior prevented my 5th from going over in November. 

[packnrat]

big words, even bigger math, all way over my head.

i just knowcwhat i have seen. 

i am not a invesgater, never trained in such.

i have seen first hand the rnd results of a number of bad accidents and never has the king pin left the fifth wheel. nor has the plate and it assamble failed.

yes frames twisted. so much thrown off the rig (including the cab). and that one was hit broadside at the leading drive axle by a train.

please do not misinterpet my thoughts here. just o see a fail in the plate assambly. 

might have saved the 5er?

might have flipped the volvo?

maybe it broke in a way designed to?

none of any info is know to me,

i did not sleep in any motel, nore had a good breakfast.

best part of all this is the couple in the truck are alright, not hurt.

[Steve from SoCal]

In looking at the picture of the hitch, I really wonder if that pivot block failed at some earlier point.    The trailer pin box is not as strong as the hitch in many trailer.    While the trailer DID twist the hitch, that alone should not have cause the failure.   One thing I noticed on my TSLB is the upper travel limit stops are small and narrow, under a significant twist of the upper hitch the arms COULD easily deflect enough to slip out.    That also seems to have occurred with this failure although it is unknown if that was because of twist or a result of the failed pivot.   

I am going out on a limb here and say, it appears that the hitch failure may have preceded the maneuver and been a significant factor of the trailer rolling.        

 

Steve 

[packnrat]

if any knowledge comes out of this i would like to know. 

as i am a info feak. just bad at spell check, using my fat fingers on this iphone.

any word from a factory rep? not sales but one who does know about the making/ limits of the assambly.

[GlennWest]

I would love to find out what Hinsley has to day about the hitch. 

[JPL]

I had no idea that I would start something like this from my post. I totaled a 2015 43" Mesa Ridge in July of 2016 and there was no real visible External damage. I didn't realize what was going on behind me until my DW called me on the cell scared to death telling me it was bouncing up and down and swaying so bad she thought I was going to roll over. The right side tires(2) had gone off the narrow 2 lane road for 30-45 seconds until I pulled it back onto the road. Most of the damage was inside (walls, slides, floor) but the frame was also found to be bent. I just never realized how bad things were behind me. At no time did the hitch fail. No time was the dog being wagged by the tail. If this had happened when I was towing with my 550 Ford the 5er and I would have been on the our side.    That is why I have chosen to tow with a HDT. It is so much safer. And again thanks to Chat for all of his help and sharing his experience with us.     Pat

 

 

The Old Sailor

 

[4Girls&aMan]

On 2/16/2018 at 8:14 AM, SuiteSuccess said:

Chet,

Totally off subject.  We usually stay at Staunton KOA when we’re going and coming from VA. But had looked at Ft. Chiswell.  Did you like it as a stopover?

We've stayed at Ft. Chiswell, also.  It was a good enough stopover.  You're not as long as we are so you should be fine.  I've used them at least a couple of times.

 

[Imurphy907]

The truck remained upright and in control during the event. No one got hurt. That is a Win Win Win in my book.

this same event in a LDT would have had the truck on its side or upside down and both of you banged up or worse.

 

Honestly I would have expected the pin box to rip off the trailer before the hitch failed. But in a situation like that, I think the hitch did a fairly good job of holding on.

[noteven]

Would that trailer have flopped it and that truck with no hitch failure?

[jkennell]

2 hours ago, Imurphy907 said:

The truck remained upright and in control during the event. No one got hurt. That is a Win Win Win in my book.

this same event in a LDT would have had the truck on its side or upside down and both of you banged up or worse.

 

Honestly I would have expected the pin box to rip off the trailer before the hitch failed. But in a situation like that, I think the hitch did a fairly good job of holding on.

AMEN.   I've seen accidents like this happen with a LDT and a bumper pull, not even a 5r.  The trailer took the LDT right around with it and the whole thing ended upside down in the median.    Your wife has 0 reason to feel bad.  She reacted correctly in a bad situation she did not cause.  She kept the truck on the road and under control.  Nobody was killed or hurt.  The trailer is replaceable.   

The hitch acted sort of like a fuse.  It held on enough that things didn't come apart, it broke enough that your truck didn't get pulled over (or even tipped hard, which could have meant the loss of control.)   I'd say you were very fortunate!

[rickeieio]

Jeff nailed it.  (And welcome back!)

A good friend has had two bumper pulls flip, one when it and the pick-up hydro planed in deep ruts on an interstate hill, and the other when he had  an out of balance situation, too much weight towards the rear.  Totaled both trailers, one pickup, and bruising to the ribs and ego. They and the dog walked away.

Any landing you can walk away from is a successful landing.  

[Padraic]

This kind of accident that keep RVer thinking. Our travel home safety has many factors that can add or subtract an unfortunate incident. HDT is a way to tow with a big/heavy 5th wheel, but accident still can happen but with better outcome.

I may have missed the three pages discussion. The trailer and truck weights were not mentioned. That would be a factor in my opinion or another angle to guess the causes. In a perfect world, we will have the opportunity to see what exactly happen. Unfortunately, most of us don't have that opportunity and only can speculate in our little mind what would I do before or during the same situation. Looking at the setup. I will assume and guessed that the truck with the smart car is heavy than the trailer when it is not used for full time. 

Since there are many factors contributed to an accident, we can only voice the part we think from our own experience. In my car defensive class, I took years ago at Escapade. An accident occurs when unfavorable numbers if items are stacking up, never just one. The instructor said those items include but not limited to, are speed, visibility(night or fog), rain, wind, fatigue, type of vehicle (RV), etc.. Our job is to lower that number to less than two. 

The hitch to me is not one of those items; no hitch is designed to hold the trailer from flip over if the forces were there to act. The sway effects(force) operated on the trailer was the truck itself. The massive truck can be a "liability"; it can be due to no (little) feedback to the driver. The truck can do more than the trailer can handle. Like "sudden" directional changes even there seems to be not that much in a stable heavy cab. If a driver been using a lighter truck, he or she would learn a different way to drive than an HDT.

In my opinion, the hitch was far from the drive axle; I think that may have amplified the force acting on the trailer and the sway force exceed the trailer design and its weight. In general, 5th wheel trailer sways less than a travel trailer which attached at the end of a truck. Conventionally, 5th wheel is more stable due to the location of the attachment to the truck, when the 5th wheel attached far from the drive axle. The setup is similar to a travel trailer. So is the design bad? Not necessary. Just need to aware when using this kind of design location while it provides many benefits.

Like the most accident on the highway, the items that were stack up from my defense driving class may be 1. Construction zone (confuse sign and narrow road), 2. Speed.

Since RV safely is much of an essential topic for all of us, I am here just to offer my two cents and not assign blame for sure. We all have accidents in our lives; it is valuable to get a different perspective to achieve the most safety on the highway.
 

[Jack Mayer]

On 2/15/2018 at 1:04 PM, mr. cob said:

I can't help but wonder if because of the short wheel base and the pin load being  that far behind the axle coupled with the weight of the Smart Car, the front axle might be light.  I am NOT saying this had anything to do with the wreck I was just wondering if you have ever had your setup weighed? 

2

A positional weight ticket would tell the story but based on what I see, I doubt if that axle is unloaded much. I've played with a LOT of these combinations so I have a pretty good feel for it - but without weight tickets, it is hard to say for sure. Anything without data is a guess....and I'm just guessing here.

[jkennell]

16 hours ago, rickeieio said:

Jeff nailed it.  (And welcome back!)

A good friend has had two bumper pulls flip, one when it and the pick-up hydro planed in deep ruts on an interstate hill, and the other when he had  an out of balance situation, too much weight towards the rear.  Totaled both trailers, one pickup, and bruising to the ribs and ego. They and the dog walked away.

Any landing you can walk away from is a successful landing.  

Thanks Rick.  Just no time to even get the HDT out anymore. My DW says no to spending 3 days getting ready for a weekend trip; haven't had a single week I could shake free in 2 years.   I am also primary caregiver for my Mom.  I need to sell it to somebody who would use it-but haven't even had a chance to clean it up for sale.  I do try to check in here once in a while!   Did you ever get the MaxBrake change done?

[rickeieio]

6 hours ago, jkennell said:

Thanks Rick.  Just no time to even get the HDT out anymore. My DW says no to spending 3 days getting ready for a weekend trip; haven't had a single week I could shake free in 2 years.   I am also primary caregiver for my Mom.  I need to sell it to somebody who would use it-but haven't even had a chance to clean it up for sale.  I do try to check in here once in a while!   Did you ever get the MaxBrake change done?

Yes, max-brake can be sent your way.  Email me.  My address is in the sig line.

[Dollytrolley]

On 2/20/2018 at 10:33 AM, Jack Mayer said:

 

 

On 2/19/2018 at 6:24 PM, rickeieio said:

 

 

On 2/18/2018 at 8:27 AM, NoDirectionHome said:

 

I gotta thank everyone helping on this thread............this has been a real eye-open-er for me the view the ........."progressive-manner-of-accident-investigation(z)............

 

On the very first accident investigation I was coerced into I was as dumb-as-a-box-of-rocks (still guilty) and so being the wet-behind-the-ears-kid-in-the-room I sat through the morning session where four Phd-big-brain geeks poured over at least a hundred pages of measurments, photos, blood alkahol-Drug-Urine-even-fingernail and hair tests of the offending deceased pilot and electron-scanning-mike-ro-scope shot of the prop-strikes and incandance-bulb-fill-e-memt-tests.................so I held my mouth shut until the Bigest of the Phd-geeks looked out over the crew and said........."any questions or comments?"...........of course being the only LEAST educated and dumb-as-a-box-of-rocks newbee in the room I stood up and said............."well shucks with that hundred pages of info any fool can see that ole Willy fummbled the throttles on takeoff and then dropped below blue-line (single-engine-control-speed) and augered in and "bought-the-farm"......"boy, boy this accident-gig thing is a piece-of-cake aint it???"

 

You could pin drop as everyone turned around with a HUGE grin on their faces and then .........Too-Tall-Paul said......"well gents....indeed this is our lucky day to have Mike drop-in and solve this accident ...........AND........ of course since he has VIOLATED the sterile rule of NEVER .........EVER......EVER....postulating on the accidents factual cause(s) UNTIL ALL data IS reviewed he IS HEREBY FINED in the TOTAL AMOUNT OF...........PRIME RIB LUNCH FOR ALL OF US!!!!!"

Yep I was...........as dumb-as-a-box-of-rocks before lunch.......BUT.....by the time lunch was over (and paid for) I was a hell-of-lot more ......."educated" about accident investigation.......

 

Thes "big-brain-geeks" got "lucky" sometimes and found some really interesting causes for accidents but it was tedious, time consuming, costly, boring, work and sometimes not able to find the exact cause of the crash in spite of all the brain-power expended....

 

I like the In-Vest-I-gation methods deployed on this thread much better and so............IF there is still some room to "crawl-out-on-the-limb" let me...... ask a dumb question............"Why is everyone looking so intensively at the truck when it is the trailer that is wrecked-laying-on-it's-side-in-the-ditch-with-a-blown-tire-and-ground-flat-wheel?  ?   ?"

Where in the "accident-chain-of-events" did the tire get shredded and the wheel grinding occure?  ?   ?

Ok.....OK ..........maybe we just vote and see who gets to buy ALL of us prime-rib lunch.......

 

Drive on..........(accident-chain-of-events..........so old school.....)

[Dollytrolley]

On 2/18/2018 at 3:31 PM, Steve from SoCal said:

 

Speaking of accidents..........I cant even operate a comment on a thread these days.....

 

Drive on..............(reboot and have another ......Dr Pepper.....)