Something is going on: Airstream rollover three

[Phoenix]

Just an observation: Looks like this discussion topic got hijacked, and it is now a Hensley/Propride thread...

Personally, I am about to click "IGNORE THIS THREAD".

[OTRA15]

Ditto.

The search results in Post #144 were an opportunity for folks to migrate to more on-topic threads, but that kind of invitation is widely ignored IMO, to the degradation of airforums.com as a useful site, in my personal opinion.

It is against the forum rules to comment on the moderation here, but . . .

Originally Posted by OTRA15

. . .
There are threads here devoted to the Hensley and Pro Pride:
https://www.google.com/search?q=hens...&bih=720&dpr=2
. . .

[ROBERT CROSS]

Originally Posted by Llando88

Ok well now I need to go look at my ProPride to see whether it was set up 'down'.

Since this is hard to visualize, have any of y'all got a picture showing this downward slope of the WD bars?

I don't really have any sway, towing a 30' FC rear queen with a Ram 2500 CTD with a PP. We've done about 30k miles since November 15. This is across the US and Canada, at up to 10% grade in Death Valley. My hitch was set up at Colonial.

Instead of a 1000 words.....



Bob

[Rfriebele]

I've seen lots of RV rollover footage from dashcams and most all of them appear to occur when the driver encounters sudden sway at speed from something....gust of wind, passing semi, tire blow, etc. and they don't know how to correct.

[slowmover]

Linkage collapse (relaxation; loss of tension) is not so much about the "bump" (maladjusted linkage plus brake setting does not have TT lead TV in application force) as it is that the trailer WILL travel faster than the TV on a downslope

Any trailer. Any tow rig.

[J. Morgan]

Originally Posted by Rfriebele

I've seen lots of RV rollover footage from dashcams and most all of them appear to occur when the driver encounters sudden sway at speed from something....gust of wind, passing semi, tire blow, etc. and they don't know how to correct.

Which to me, as a matter of SAFETY, means that new towers need to strongly consider the stability benefits of hitch systems that CAN NOT sway.

Would we be talking about any of the three accidents if it wasn't for trailer sway?

[Rich Jenkins]

Originally Posted by ROBERT CROSS

Instead of a 1000 words.....







Bob

Thanks Bob. That's very helpful.

Now, back to the bickering...

[Rich Jenkins]

Actually I have a question.

Does anyone know if modern TV factory braking systems do or do not apply the TT brakes slightly ahead of the TV?

Seems it would be possible for software to do this. The TV knows it's in tow/haul mode (mine has a switch) and it also knows there is a TT attached (via the umbilical.)

Thoughts?

[slowmover]

Originally Posted by J. Morgan

I keep my trailer brakes adjusted, but never has happened to me. I think that even if it did, it would be essentially a non event. The trailer can't sway in that kind of lock either.

It's not a question of whether a problem of control has arisen, it's that NO hitch maintains tension without the TV moving faster than the TT whether by throttle or trailer brake application.

A control problem CAN arise downslope (for those of you not paying attention to why VPP hitch particulars are germane), as EVERY combined vehicle of EVERY description is vulnerable during this passage. A VPP is no exception. It is not locked without TT brake application.

Let me say this again: Control of downslope speed via diesel engine exhaust brake or gas motor transmission programming WITHOUT use of TT brakes is an unsafe condition.

Downslope target speed, application of brakes, and (as always) maintaining distance from other vehicles. If the chosen speed is 40-mph (my favorite with personal rig) one is inside an envelope 35-45/mph. Roll to 45, use brakes to slow to 35; repeat. All the way down. Slow enough to maneuver, slow enough to maintain drum brake effectiveness, slow enough to use throttle and brakes simultaneously when things get pear-shaped (given distance to run; room to accelerate).

40-mph is also low enough that crosswinds effect the rig over a shorter distance travelled. That probably covers this thread topic: too fast for conditions.

The speed given is an example. Some downslopes will be necessarily slower. 40 can be far too fast.

Just sure as hell I don't want to be ahead of a tractor-trailer. I'll modify what I do to avoid that. It's what I'm thinking about while upslope given what my mirrors are telling me. In fact, well before the ascent. Some big trucks will be running as hard as they can AT the slope. I'd like to have them away from me, and will back off ascent speed so to not have to pass them (situational).

Marked downgrades (road warning sign with grade percentage) should all be respected. I'm unlikely to choose higher than 45 as I hope all of you notice that the fools race to the bottom of the Interstate grade and leave no appreciable room ahead of them. They've bunched up as the outer descent lanes disappear (can't fix stupid).

If one wants an instance to illustrate the sheer foolishness of THE HABIT of "keeping up with traffic flow", this is it: there's no where to go should a semi lose his brakes back upslope. He'll hit 90-mph faster than you can believe. And his rate of acceleration will be climbing like a jet fighter .

He won't have Major Kongs sanguine acceptance of fate.

On a miles long downgrade, others around you will freak out. Count on it. A chain reaction set of wrecks. Thus if one is on the brakes, remember that those trailer drums have limited effectiveness given speed, mass and distance. You've a short window to maintain control.

Make your speed downslope "bulletproof".

THAT's the habit to have, as it is always applicable: space & time at a speed even a pickup can safely maneuver.

Do NOT expect that you can make it onto the shoulder if you aren't already in the outside lane. The other big trucks will be backing off as hard as they can and will be diving towards that lane, as they know that the driver of the truck or trucks caught in between others aren't going to make it. It's sayonara time. The wrecks will sequence back up the slope.

The likelihood of that driver with failed brakes making it onto an emergency ramp aren't high. Expect him to roll it over. And block the road.

Etc.

Crosswind gusts are the constant problem. A semi passing too close will cause the trailer to sway uncontrollably, not just local wind features. But the above example should always factor into decisions.

.

[J. Morgan]

Originally Posted by slowmover

It's not a question of whether a problem of control has arisen, it's that NO hitch maintains tension without the TV moving faster than the TT whether by throttle or trailer brake application.



A control problem CAN arise downslope (for those of you not paying attention to why VPP hitch particulars are germane), as EVERY combined vehicle of EVERY description is vulnerable during this passage. A VPP is no exception. It is not locked without TT brake application.



Let me say this again: Control of downslope speed via diesel engine exhaust brake or gas motor transmission programming WITHOUT use of TT brakes is an unsafe condition.



Downslope target speed, application of brakes, and (as always) maintaining distance from other vehicles. If the chosen speed is 40-mph (my favorite with personal rig) one is inside an envelope 35-45/mph. Roll to 45, use brakes to slow to 35; repeat. All the way down. Slow enough to maneuver, slow enough to maintain drum brake effectiveness, slow enough to use throttle and brakes simultaneously when things get pear-shaped (given distance to run; room to accelerate).



40-mph is also low enough that crosswinds effect the rig over a shorter distance travelled. That probably covers this thread topic: too fast for conditions.



The speed given is an example. Some downslopes will be necessarily slower. 40 can be far too fast.



Just sure as hell I don't want to be ahead of a tractor-trailer. I'll modify what I do to avoid that. It's what I'm thinking about while upslope given what my mirrors are telling me. In fact, well before the ascent. Some big trucks will be running as hard as they can AT the slope. I'd like to have them away from me, and will back off ascent speed so to not have to pass them (situational).



Marked downgrades (road warning sign with grade percentage) should all be respected. I'm unlikely to choose higher than 45 as I hope all of you notice that the fools race to the bottom of the Interstate grade and leave no appreciable room ahead of them. They've bunched up as the outer descent lanes disappear (can't fix stupid).



If one wants an instance to illustrate the sheer foolishness of THE HABIT of "keeping up with traffic flow", this is it: there's no where to go should a semi lose his brakes back upslope. He'll hit 90-mph faster than you can believe. And his rate of acceleration will be climbing like a jet fighter .



He won't have Major Kongs sanguine acceptance of fate.



On a miles long downgrade, others around you will freak out. Count on it. A chain reaction set of wrecks. Thus if one is on the brakes, remember that those trailer drums have limited effectiveness given speed, mass and distance. You've a short window to maintain control.



Make your speed downslope "bulletproof".



THAT's the habit to have, as it is always applicable: space & time at a speed even a pickup can safely maneuver.



Do NOT expect that you can make it onto the shoulder if you aren't already in the outside lane. The other big trucks will be backing off as hard as they can and will be diving towards that lane, as they know that the driver of the truck or trucks caught in between others aren't going to make it. It's sayonara time. The wrecks will sequence back up the slope.



The likelihood of that driver with failed brakes making it onto an emergency ramp aren't high. Expect him to roll it over. And block the road.



Etc.



Crosswind gusts are the constant problem. A semi passing too close will cause the trailer to sway uncontrollably, not just local wind features. But the above example should always factor into decisions.



.

My trailer has stayed straight behind my trailer without exception ever since I installed my Hensley, even down long 8% grades. I never feel a truck pass me, or feel one when I pass one.

[J. Morgan]

Originally Posted by Llando88

Actually I have a question.

Does anyone know if modern TV factory braking systems do or do not apply the TT brakes slightly ahead of the TV?

Seems it would be possible for software to do this. The TV knows it's in tow/haul mode (mine has a switch) and it also knows there is a TT attached (via the umbilical.)

Thoughts?

I don't know, but I do know that my aftermarket brake controller will apply the trailer brakes as soon as the brake lights come on. By using a light touch on the brake pedal early on, the trailer brakes work first, and then I use the TV brakes as needed by pressing the pedal harder.

[slowmover]

Originally Posted by J. Morgan

My trailer has stayed straight behind my trailer without exception ever since I installed my Hensley, even down long 8% grades. I never feel a truck pass me, or feel one when I pass one.

Let's get this over with. When backing straight, is the linkage collapsed?

Of course it is.

And to varying distances, so will it be on a downgrade.

Thus, the amount of time in that state matters.

The hitch isn't a problem, it's operator awareness of that vulnerability.

Should go without saying that vehicle specification (both), hitch design and a by-the-numbers vehicle lash-up all count now more than ever.

Have missed your posts. Anyone who's read them knows you went to painstaking length to get it right.

I've long figured that if you passed me I'd recognize your rig. And not simply by picture correlation, but obvious driver skill and a well-sorted rig.

The bad ones are the norm. I should get a dash cam and put to Spike Jones the brand-new one-tons yanking a 25' bouncing along on the front axle in a compilation vid, ha!

.

[J. Morgan]

Originally Posted by slowmover

Let's get this over with. When backing straight, is the linkage collapsed?



Of course it is.



And to varying distances, so will it be on a downgrade.



Thus, the amount of time in that state matters.



The hitch isn't a problem, it's operator awareness of that vulnerability.



Should go without saying that vehicle specification (both), hitch design and a by-the-numbers vehicle lash-up all count now more than ever.



Have missed your posts. Anyone who's read them knows you went to painstaking length to get it right.



I've long figured that if you passed me I'd recognize your rig. And not simply by picture correlation, but obvious driver skill and a well-sorted rig.



The bad ones are the norm. I should get a dash cam and put to Spike Jones the brand-new one-tons yanking a 25' bouncing along on the front axle in a compilation vid, ha!



.

If it is collapsed when backing, which it may or may not be, I have never looked, so what?

like I say, over my heavy use of my Hensley equipped trailer over mountainous terrain for three years now, my experience is that the trailer is every bit as stable going down a hill as it is going up. What I am saying is that since installing the Hensley, I have had zero incidence of sway, and the rig handles like it is riding on rails at any speed I might have taken it to.

[J. Morgan]

Originally Posted by J. Morgan

If it is collapsed when backing, which it may or may not be, I have never looked, so what?

like I say, over my heavy use of my Hensley equipped trailer over mountainous terrain for three years now, my experience is that the trailer is every bit as stable going down a hill as it is going up. What I am saying is that since installing the Hensley, I have had zero incidence of sway, and the rig handles like it is riding on rails at any speed I might have taken it to.

I go to Globe AZ frequently up Hwy 77, long 7 and 8 percent grades here, to Bisbee dozens of times, no collapse that I have ever noticed even when leaving the Queen Mine RV park. To me, this collapse, even if it happens, is a non event from the drivers seat.

[Rfriebele]

Originally Posted by J. Morgan

Which to me, as a matter of SAFETY, means that new towers need to strongly consider the stability benefits of hitch systems that CAN NOT sway.

Would we be talking about any of the three accidents if it wasn't for trailer sway?

Only thing I know that can't really sway is a fifth wheel. All the hitch precautions one might take otherwise can't stop high wind, tire blowout or the draft of a semi imparting some sway on your trailer. Of course the better your hitch setup, the more it will minimize and help correct it IF you don't make it worse trying to over correct and that's what I see these unfortunate accident victims doing. What starts small in the realm of ordinary quickly balloons out of control due to steering error.

[slowmover]

Originally Posted by Rfriebele

Only thing I know that can't really sway is a fifth wheel. All the hitch precautions one might take otherwise can't stop high wind, tire blowout or the draft of a semi imparting some sway on your trailer. Of course the better your hitch setup, the more it will minimize and help correct it IF you don't make it worse trying to over correct and that's what I see these unfortunate accident victims doing. What starts small in the realm of ordinary quickly balloons out of control due to steering error.

5'ers will sway. So will big trucks. NONE are exempt. I didn't make that clear? All are dependent on hitch tension.

Few things are worse on the road than a 5er. The hitch is great, the trailer attached is terrible. They turn over almost instantly.

[J. Morgan]

Originally Posted by J. Morgan

I go to Globe AZ frequently up Hwy 77, long 7 and 8 percent grades here, to Bisbee dozens of times, no collapse that I have ever noticed even when leaving the Queen Mine RV park. To me, this collapse, even if it happens, is a non event from the drivers seat.

The bottom line is the safety that a super stable vehicle provides by its very nature, a vehicle that is stable up hill and down hill, and is stable even if an inexperienced driver drives it too fast down a grade.

My loaded question is still the same, if these three vehicles had used a ProPride or Hensley, would we be discussing these accidents at all? I say chances are, we wouldn't.

[J. Morgan]

Originally Posted by slowmover

5'ers will sway. So will big trucks. NONE are exempt. I didn't make that clear? All are dependent on hitch tension.



Few things are worse on the road than a 5er. The hitch is great, the trailer attached is terrible. They turn over almost instantly.

I have seen doubles and stinger towed car haulers sway, I have never experienced sway pulling a single fifth wheel trailer, ever. None of the fifth wheel rigs I have used in my business over the past 30 plus years sway, ever.

Likewise, my Hensley equipped Airstream has never swayed, ever. Not once.

[majorairhead]

I'm a 57 year old cat that doesn't really know too much but I have a hunch SPEED played/plays a significant factor in these towing accidents......just sayin.

[jcl]

Originally Posted by J. Morgan

I have seen doubles and stinger towed car haulers sway, I have never experienced sway pulling a single fifth wheel trailer, ever. None of the fifth wheel rigs I have used in my business over the past 30 plus years sway, ever.

Likewise, my Hensley equipped Airstream has never swayed, ever. Not once.

We may be using different definitions of sway here.

In my experience, all trailers sway. You can follow them, all designs and hitch configurations, and watch it. Usually there is sufficient damping inherent in the system so that it isn't a problem, and often the person driving will be unaware of it, but may be able to see it in their mirrors.

The problem is when there is insufficient damping, and then we get escalating sway events that get discussed on forums. That is the type of sway that some may be referring to when they say that their trailer has never swayed. It is a different definition of sway, however.

IMO, this difference in definitions makes the PPP vs all the others debate more difficult because of a lack of agreement on basic terms.