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"TheSnoMan" <admin@snoman.com> wrote in message
news:rY5Bf.11752$ZA2.9222@newsread1.news.atl.earthlink.net...
> William Boyd wrote:
> > TheSnoMan wrote:
> >
> >> John S. wrote:
> >>
> >>> Joe wrote:
> >>>
> >>>> I got really curious about this, and studied it for a long time (I'm
an
> >>>> engineer). There was a good thread on this at woodall's RV forum. I
> >>>> have
> >>>> found no frank discussion of it by anybody who has broken it down
> >>>> into its
> >>>> component forces. It's hard to explain it using ASCII here. But my
> >>>> opinion
> >>>> is this:
> >>>>
> >>>> First off, it's clear that trailers can amplify their swaying until
you
> >>>> crash. They don't do it all the time, but they can, and that's what
> >>>> interests me. They have no power of their own to bring to the table.
> >>>> The
> >>>> energy to do this comes from the tow vehicle. The trailer sways like
a
> >>>> pendulum, sort of (I admit the forces holding a trailer back are not
> >>>> exactly
> >>>> like gravity in this analogy). A pendulum can be powered by a wide
> >>>> variety
> >>>> of motions. One of those motions is moving the pendulum's pivot
> >>>> point side
> >>>> to side. I think this is the motion we want.
> >>>>
> >>>> The forces on the trailer come from its tires and the tow vehicle. I
> >>>> was not
> >>>> interested in any other forces. "front loaded" trailers are trailers
> >>>> where
> >>>> the center of gravity is in front of the tires. When the tires are
> >>>> pushing
> >>>> the trailer sideways (during sway), the center of gravity is in
> >>>> front of
> >>>> that force. Since the side force doesn't go exactly through the
> >>>> center of
> >>>> gravity, the weight of the trailer pushes sideways on the tow
vehicle.
> >>>>
> >>>> The inertia of the swaying trailer pushes the tow vehicle from side
> >>>> to side.
> >>>> The difference in loading is simply this. If the center of gravity
> >>>> is in
> >>>> front of the wheels, it pushed the tow vehicle one way, and if it's
> >>>> behind
> >>>> the wheels, it pushes the two vehicle the other way. One cancels the
> >>>> sway,
> >>>> and the other amplifies it.
> >>>>
> >>>
> >>>
> >>> I don't know if amplification is the correct term. Poor loading will
> >>> increase the sensitivity of a tow vehicle and trailer to winds and
side
> >>> drafts from big trucks, but I don't understand how the forces could
> >>> actually be amplified. In my experience the side-to-side swaying is
> >>> amplified or increased by the driver trying to offset the swaying by
> >>> steering out of it.
> >>>
> >>
> >> This is true and just about all trailer sway issue start with tow
> >> vehicle stabilty issues. (tires and suspension not up to the extra
> >> load on them)
> >>
> > I do not agree. I think trailer sway issues start with proper loading.
> > I do agree that tow vehicle stability issues can be attributed to tire
> > and suspension problems. But they will not be the primary cause of sway,
> > the distribution of the load will be. Even a trailer that is grossly
> > over loaded may not sway if the CG is correct. But this is where the tow
> > vehicle suspension and tire pressure will show up more readily.
> > And I am no mechanical engineer or whatever scientist, but a retired
> > transportation superintendent with a lot of miles behind me. ;-)
> >
> CG is a factor but if your TV is not up to the load, it will be
> unstable. Your TV has to effectively anchor the front of the trailer
> where you want it to be and if trailer force easily deflect the TV's
> controll of this, you will have sway. Correct CG on a poor TV can still
> be quite unstable while even some CG error can do well if the TV is
> stout enough.
>
I think you have it there. The TV is the driving force that keeps the sway
going. And the reason that a 5th wheel or trailers using a Hensley or
Pullrite hitch pretty much eliminate the problem.
Suppose you pulled a badly loaded but small trailer behind a semi tractor.
If the trailer deflected due to wind, the truck would not move and would
pull the trailer back into position. But when pulled by a small vehicle,
the rear of the TV would be pulled out of position. As it tries to pull
the trailer back into position and straighten itself out it could put energy
into the system causing the trailer to swing even further in the opposite
direction. The rear of the TV also swings even further setting up an
oscillation.
I talked to a couple that had a new 30 foot trailer and new tow vehicle and
were using a Hensley hitch. The previous year they started off on vacation
with a similar set up except using a standard platform hitch. They got
about 30 miles from home when the trailer began to sway and before they
could react it rolled.
TheSnoMan wrote:
> John S. wrote:
> > Joe wrote:
> >
> >>I got really curious about this, and studied it for a long time (I'm an
> >>engineer). There was a good thread on this at woodall's RV forum. I have
> >>found no frank discussion of it by anybody who has broken it down into its
> >>component forces. It's hard to explain it using ASCII here. But my opinion
> >>is this:
> >>
> >>First off, it's clear that trailers can amplify their swaying until you
> >>crash. They don't do it all the time, but they can, and that's what
> >>interests me. They have no power of their own to bring to the table. The
> >>energy to do this comes from the tow vehicle. The trailer sways like a
> >>pendulum, sort of (I admit the forces holding a trailer back are not exactly
> >>like gravity in this analogy). A pendulum can be powered by a wide variety
> >>of motions. One of those motions is moving the pendulum's pivot point side
> >>to side. I think this is the motion we want.
> >>
> >>The forces on the trailer come from its tires and the tow vehicle. I was not
> >>interested in any other forces. "front loaded" trailers are trailers where
> >>the center of gravity is in front of the tires. When the tires are pushing
> >>the trailer sideways (during sway), the center of gravity is in front of
> >>that force. Since the side force doesn't go exactly through the center of
> >>gravity, the weight of the trailer pushes sideways on the tow vehicle.
> >>
> >>The inertia of the swaying trailer pushes the tow vehicle from side to side.
> >>The difference in loading is simply this. If the center of gravity is in
> >>front of the wheels, it pushed the tow vehicle one way, and if it's behind
> >>the wheels, it pushes the two vehicle the other way. One cancels the sway,
> >>and the other amplifies it.
> >>
> >
> >
> > I don't know if amplification is the correct term. Poor loading will
> > increase the sensitivity of a tow vehicle and trailer to winds and side
> > drafts from big trucks, but I don't understand how the forces could
> > actually be amplified. In my experience the side-to-side swaying is
> > amplified or increased by the driver trying to offset the swaying by
> > steering out of it.
> >
>
> This is true and just about all trailer sway issue start with tow
> vehicle stabilty issues. (tires and suspension not up to the extra load
> on them)
>
Yup...too big a trailer for the vehicle and an incorrest tow bar adds
up to the potential for big problems. Add to that the tendency for
inexperienced drivers to go too fast for conditions, especially on the
downhill and you have a recipe for a serious accident.
A family member was towing a large trailer with a Suburban and got
caught in a truck sidedraft when going too fast downhill on the way to
Wyoming. Rather than holding it steady he tried to compensate and
ended up flipping the trailer and spinning the truck round in traffic.
No injuries thanks to some fast thinking truckers.
Rich256 wrote:
> "TheSnoMan" <admin@snoman.com> wrote in message
> news:rY5Bf.11752$ZA2.9222@newsread1.news.atl.earthlink.net...
>
>>William Boyd wrote:
>>
>>>TheSnoMan wrote:
>>>
>>>
>>>>John S. wrote:
>>>>
>>>>
>>>>>Joe wrote:
>>>>>
>>>>>
>>>>>>I got really curious about this, and studied it for a long time (I'm
>
> an
>
>>>>>>engineer). There was a good thread on this at woodall's RV forum. I
>>>>>>have
>>>>>>found no frank discussion of it by anybody who has broken it down
>>>>>>into its
>>>>>>component forces. It's hard to explain it using ASCII here. But my
>>>>>>opinion
>>>>>>is this:
>>>>>>
>>>>>>First off, it's clear that trailers can amplify their swaying until
>
> you
>
>>>>>>crash. They don't do it all the time, but they can, and that's what
>>>>>>interests me. They have no power of their own to bring to the table.
>>>>>>The
>>>>>>energy to do this comes from the tow vehicle. The trailer sways like
>
> a
>
>>>>>>pendulum, sort of (I admit the forces holding a trailer back are not
>>>>>>exactly
>>>>>>like gravity in this analogy). A pendulum can be powered by a wide
>>>>>>variety
>>>>>>of motions. One of those motions is moving the pendulum's pivot
>>>>>>point side
>>>>>>to side. I think this is the motion we want.
>>>>>>
>>>>>>The forces on the trailer come from its tires and the tow vehicle. I
>>>>>>was not
>>>>>>interested in any other forces. "front loaded" trailers are trailers
>>>>>>where
>>>>>>the center of gravity is in front of the tires. When the tires are
>>>>>>pushing
>>>>>>the trailer sideways (during sway), the center of gravity is in
>>>>>>front of
>>>>>>that force. Since the side force doesn't go exactly through the
>>>>>>center of
>>>>>>gravity, the weight of the trailer pushes sideways on the tow
>
> vehicle.
>
>>>>>>The inertia of the swaying trailer pushes the tow vehicle from side
>>>>>>to side.
>>>>>>The difference in loading is simply this. If the center of gravity
>>>>>>is in
>>>>>>front of the wheels, it pushed the tow vehicle one way, and if it's
>>>>>>behind
>>>>>>the wheels, it pushes the two vehicle the other way. One cancels the
>>>>>>sway,
>>>>>>and the other amplifies it.
>>>>>>
>>>>>
>>>>>
>>>>>I don't know if amplification is the correct term. Poor loading will
>>>>>increase the sensitivity of a tow vehicle and trailer to winds and
>
> side
>
>>>>>drafts from big trucks, but I don't understand how the forces could
>>>>>actually be amplified. In my experience the side-to-side swaying is
>>>>>amplified or increased by the driver trying to offset the swaying by
>>>>>steering out of it.
>>>>>
>>>>
>>>>This is true and just about all trailer sway issue start with tow
>>>>vehicle stabilty issues. (tires and suspension not up to the extra
>>>>load on them)
>>>>
>>>
>>>I do not agree. I think trailer sway issues start with proper loading.
>>>I do agree that tow vehicle stability issues can be attributed to tire
>>>and suspension problems. But they will not be the primary cause of sway,
>>>the distribution of the load will be. Even a trailer that is grossly
>>>over loaded may not sway if the CG is correct. But this is where the tow
>>>vehicle suspension and tire pressure will show up more readily.
>>>And I am no mechanical engineer or whatever scientist, but a retired
>>>transportation superintendent with a lot of miles behind me. ;-)
>>>
>>
>> CG is a factor but if your TV is not up to the load, it will be
>>unstable. Your TV has to effectively anchor the front of the trailer
>>where you want it to be and if trailer force easily deflect the TV's
>>controll of this, you will have sway. Correct CG on a poor TV can still
>>be quite unstable while even some CG error can do well if the TV is
>>stout enough.
>>
>
>
>
> I think you have it there. The TV is the driving force that keeps the sway
> going. And the reason that a 5th wheel or trailers using a Hensley or
> Pullrite hitch pretty much eliminate the problem.
>
> Suppose you pulled a badly loaded but small trailer behind a semi tractor.
> If the trailer deflected due to wind, the truck would not move and would
> pull the trailer back into position. But when pulled by a small vehicle,
> the rear of the TV would be pulled out of position. As it tries to pull
> the trailer back into position and straighten itself out it could put energy
> into the system causing the trailer to swing even further in the opposite
> direction. The rear of the TV also swings even further setting up an
> oscillation.
>
> I talked to a couple that had a new 30 foot trailer and new tow vehicle and
> were using a Hensley hitch. The previous year they started off on vacation
> with a similar set up except using a standard platform hitch. They got
> about 30 miles from home when the trailer began to sway and before they
> could react it rolled.
>
>
>
TheSnoMan wrote:
> Rich256 wrote:
>
>> "TheSnoMan" <admin@snoman.com> wrote in message
>> news:rY5Bf.11752$ZA2.9222@newsread1.news.atl.earthlink.net...
>>
>>> William Boyd wrote:
>>>
>>>> TheSnoMan wrote:
>>>>
>>>>
>>>>> John S. wrote:
>>>>>
>>>>>
>>>>>> Joe wrote:
>>>>>>
>>>>>>
>>>>>>> I got really curious about this, and studied it for a long time (I'm
>>
>>
>> an
>>
>>>>>>> engineer). There was a good thread on this at woodall's RV forum. I
>>>>>>> have
>>>>>>> found no frank discussion of it by anybody who has broken it down
>>>>>>> into its
>>>>>>> component forces. It's hard to explain it using ASCII here. But my
>>>>>>> opinion
>>>>>>> is this:
>>>>>>>
>>>>>>> First off, it's clear that trailers can amplify their swaying until
>>
>>
>> you
>>
>>>>>>> crash. They don't do it all the time, but they can, and that's what
>>>>>>> interests me. They have no power of their own to bring to the table.
>>>>>>> The
>>>>>>> energy to do this comes from the tow vehicle. The trailer sways like
>>
>>
>> a
>>
>>>>>>> pendulum, sort of (I admit the forces holding a trailer back are not
>>>>>>> exactly
>>>>>>> like gravity in this analogy). A pendulum can be powered by a wide
>>>>>>> variety
>>>>>>> of motions. One of those motions is moving the pendulum's pivot
>>>>>>> point side
>>>>>>> to side. I think this is the motion we want.
>>>>>>>
>>>>>>> The forces on the trailer come from its tires and the tow vehicle. I
>>>>>>> was not
>>>>>>> interested in any other forces. "front loaded" trailers are trailers
>>>>>>> where
>>>>>>> the center of gravity is in front of the tires. When the tires are
>>>>>>> pushing
>>>>>>> the trailer sideways (during sway), the center of gravity is in
>>>>>>> front of
>>>>>>> that force. Since the side force doesn't go exactly through the
>>>>>>> center of
>>>>>>> gravity, the weight of the trailer pushes sideways on the tow
>>
>>
>> vehicle.
>>
>>>>>>> The inertia of the swaying trailer pushes the tow vehicle from side
>>>>>>> to side.
>>>>>>> The difference in loading is simply this. If the center of gravity
>>>>>>> is in
>>>>>>> front of the wheels, it pushed the tow vehicle one way, and if it's
>>>>>>> behind
>>>>>>> the wheels, it pushes the two vehicle the other way. One cancels the
>>>>>>> sway,
>>>>>>> and the other amplifies it.
>>>>>>>
>>>>>>
>>>>>>
>>>>>> I don't know if amplification is the correct term. Poor loading will
>>>>>> increase the sensitivity of a tow vehicle and trailer to winds and
>>
>>
>> side
>>
>>>>>> drafts from big trucks, but I don't understand how the forces could
>>>>>> actually be amplified. In my experience the side-to-side swaying is
>>>>>> amplified or increased by the driver trying to offset the swaying by
>>>>>> steering out of it.
>>>>>>
>>>>>
>>>>> This is true and just about all trailer sway issue start with tow
>>>>> vehicle stabilty issues. (tires and suspension not up to the extra
>>>>> load on them)
>>>>>
>>>>
>>>> I do not agree. I think trailer sway issues start with proper loading.
>>>> I do agree that tow vehicle stability issues can be attributed to tire
>>>> and suspension problems. But they will not be the primary cause of
>>>> sway,
>>>> the distribution of the load will be. Even a trailer that is grossly
>>>> over loaded may not sway if the CG is correct. But this is where the
>>>> tow
>>>> vehicle suspension and tire pressure will show up more readily.
>>>> And I am no mechanical engineer or whatever scientist, but a retired
>>>> transportation superintendent with a lot of miles behind me. ;-)
>>>>
>>>
>>> CG is a factor but if your TV is not up to the load, it will be
>>> unstable. Your TV has to effectively anchor the front of the trailer
>>> where you want it to be and if trailer force easily deflect the TV's
>>> controll of this, you will have sway. Correct CG on a poor TV can still
>>> be quite unstable while even some CG error can do well if the TV is
>>> stout enough.
>>>
>>
>>
>>
>> I think you have it there. The TV is the driving force that keeps the
>> sway
>> going. And the reason that a 5th wheel or trailers using a Hensley or
>> Pullrite hitch pretty much eliminate the problem.
>>
>> Suppose you pulled a badly loaded but small trailer behind a semi
>> tractor.
>> If the trailer deflected due to wind, the truck would not move and would
>> pull the trailer back into position. But when pulled by a small vehicle,
>> the rear of the TV would be pulled out of position. As it tries to
>> pull
>> the trailer back into position and straighten itself out it could put
>> energy
>> into the system causing the trailer to swing even further in the opposite
>> direction. The rear of the TV also swings even further setting up an
>> oscillation.
>>
>> I talked to a couple that had a new 30 foot trailer and new tow
>> vehicle and
>> were using a Hensley hitch. The previous year they started off on
>> vacation
>> with a similar set up except using a standard platform hitch. They got
>> about 30 miles from home when the trailer began to sway and before they
>> could react it rolled.
>>
>>
>>
>
>
> Bet is was a 1/2 ton P/U or SUV pulling it too.
>
I also want to add if you are quick on your feet and apply trailer
brakes when this happens (not vehicle brakes because it can make it
worse) you can usually get it under control if you catch it in time.
Actually a Helsley or Pullrite will "reduce" the tendency for the towed
vehicle to sway the towing vehicle, but it will not eliminate it, their
websites notwithstanding. They are a better solution that a standard
hitch because the pivot point is moved closer to the rear axle. A
fifth wheel places the pivot point between the wheels, thus further
reducing but not eliminating the ability of the towed vehicle to alter
the direction of the towing vehicle.
> I think you have it there. The TV is the driving force that keeps the sway
> going. And the reason that a 5th wheel or trailers using a Hensley or
> Pullrite hitch pretty much eliminate the problem.
>
> Suppose you pulled a badly loaded but small trailer behind a semi tractor.
> If the trailer deflected due to wind, the truck would not move and would
> pull the trailer back into position. But when pulled by a small vehicle,
> the rear of the TV would be pulled out of position. As it tries to pull
> the trailer back into position and straighten itself out it could put energy
> into the system causing the trailer to swing even further in the opposite
> direction. The rear of the TV also swings even further setting up an
> oscillation.
>
> I talked to a couple that had a new 30 foot trailer and new tow vehicle and
> were using a Hensley hitch. The previous year they started off on vacation
> with a similar set up except using a standard platform hitch. They got
> about 30 miles from home when the trailer began to sway and before they
> could react it rolled.
"TheSnoMan" <admin@snoman.com> wrote in message
news:Ck7Bf.5206$vU2.5042@newsread3.news.atl.earthlink.net...
> TheSnoMan wrote:
> > Rich256 wrote:
> >
> >> "TheSnoMan" <admin@snoman.com> wrote in message
> >> news:rY5Bf.11752$ZA2.9222@newsread1.news.atl.earthlink.net...
> >>
> >>> William Boyd wrote:
> >>>
> >>>> TheSnoMan wrote:
> >>>>
> >>>>
> >>>>> John S. wrote:
> >>>>>
> >>>>>
> >>>>>> Joe wrote:
> >>>>>>
> >>>>>>
> >>>>>>> I got really curious about this, and studied it for a long time
(I'm
> >>
> >>
> >> an
> >>
> >>>>>>> engineer). There was a good thread on this at woodall's RV forum.
I
> >>>>>>> have
> >>>>>>> found no frank discussion of it by anybody who has broken it down
> >>>>>>> into its
> >>>>>>> component forces. It's hard to explain it using ASCII here. But my
> >>>>>>> opinion
> >>>>>>> is this:
> >>>>>>>
> >>>>>>> First off, it's clear that trailers can amplify their swaying
until
> >>
> >>
> >> you
> >>
> >>>>>>> crash. They don't do it all the time, but they can, and that's
what
> >>>>>>> interests me. They have no power of their own to bring to the
table.
> >>>>>>> The
> >>>>>>> energy to do this comes from the tow vehicle. The trailer sways
like
> >>
> >>
> >> a
> >>
> >>>>>>> pendulum, sort of (I admit the forces holding a trailer back are
not
> >>>>>>> exactly
> >>>>>>> like gravity in this analogy). A pendulum can be powered by a wide
> >>>>>>> variety
> >>>>>>> of motions. One of those motions is moving the pendulum's pivot
> >>>>>>> point side
> >>>>>>> to side. I think this is the motion we want.
> >>>>>>>
> >>>>>>> The forces on the trailer come from its tires and the tow vehicle.
I
> >>>>>>> was not
> >>>>>>> interested in any other forces. "front loaded" trailers are
trailers
> >>>>>>> where
> >>>>>>> the center of gravity is in front of the tires. When the tires are
> >>>>>>> pushing
> >>>>>>> the trailer sideways (during sway), the center of gravity is in
> >>>>>>> front of
> >>>>>>> that force. Since the side force doesn't go exactly through the
> >>>>>>> center of
> >>>>>>> gravity, the weight of the trailer pushes sideways on the tow
> >>
> >>
> >> vehicle.
> >>
> >>>>>>> The inertia of the swaying trailer pushes the tow vehicle from
side
> >>>>>>> to side.
> >>>>>>> The difference in loading is simply this. If the center of gravity
> >>>>>>> is in
> >>>>>>> front of the wheels, it pushed the tow vehicle one way, and if
it's
> >>>>>>> behind
> >>>>>>> the wheels, it pushes the two vehicle the other way. One cancels
the
> >>>>>>> sway,
> >>>>>>> and the other amplifies it.
> >>>>>>>
> >>>>>>
> >>>>>>
> >>>>>> I don't know if amplification is the correct term. Poor loading
will
> >>>>>> increase the sensitivity of a tow vehicle and trailer to winds and
> >>
> >>
> >> side
> >>
> >>>>>> drafts from big trucks, but I don't understand how the forces could
> >>>>>> actually be amplified. In my experience the side-to-side swaying
is
> >>>>>> amplified or increased by the driver trying to offset the swaying
by
> >>>>>> steering out of it.
> >>>>>>
> >>>>>
> >>>>> This is true and just about all trailer sway issue start with tow
> >>>>> vehicle stabilty issues. (tires and suspension not up to the extra
> >>>>> load on them)
> >>>>>
> >>>>
> >>>> I do not agree. I think trailer sway issues start with proper
loading.
> >>>> I do agree that tow vehicle stability issues can be attributed to
tire
> >>>> and suspension problems. But they will not be the primary cause of
> >>>> sway,
> >>>> the distribution of the load will be. Even a trailer that is grossly
> >>>> over loaded may not sway if the CG is correct. But this is where the
> >>>> tow
> >>>> vehicle suspension and tire pressure will show up more readily.
> >>>> And I am no mechanical engineer or whatever scientist, but a retired
> >>>> transportation superintendent with a lot of miles behind me. ;-)
> >>>>
> >>>
> >>> CG is a factor but if your TV is not up to the load, it will be
> >>> unstable. Your TV has to effectively anchor the front of the trailer
> >>> where you want it to be and if trailer force easily deflect the TV's
> >>> controll of this, you will have sway. Correct CG on a poor TV can
still
> >>> be quite unstable while even some CG error can do well if the TV is
> >>> stout enough.
> >>>
> >>
> >>
> >>
> >> I think you have it there. The TV is the driving force that keeps the
> >> sway
> >> going. And the reason that a 5th wheel or trailers using a Hensley
or
> >> Pullrite hitch pretty much eliminate the problem.
> >>
> >> Suppose you pulled a badly loaded but small trailer behind a semi
> >> tractor.
> >> If the trailer deflected due to wind, the truck would not move and
would
> >> pull the trailer back into position. But when pulled by a small
vehicle,
> >> the rear of the TV would be pulled out of position. As it tries to
> >> pull
> >> the trailer back into position and straighten itself out it could put
> >> energy
> >> into the system causing the trailer to swing even further in the
opposite
> >> direction. The rear of the TV also swings even further setting up an
> >> oscillation.
> >>
> >> I talked to a couple that had a new 30 foot trailer and new tow
> >> vehicle and
> >> were using a Hensley hitch. The previous year they started off on
> >> vacation
> >> with a similar set up except using a standard platform hitch. They got
> >> about 30 miles from home when the trailer began to sway and before they
> >> could react it rolled.
> >>
> >>
> >>
> >
> >
> > Bet is was a 1/2 ton P/U or SUV pulling it too.
> >
>
>
> I also want to add if you are quick on your feet and apply trailer
> brakes when this happens (not vehicle brakes because it can make it
> worse) you can usually get it under control if you catch it in time.
>
Been there. Did it. Coming down a steep mountain road, going too fast,
encounted a strong cross wind out of a canyon. Trailer brakes pulled it
right back into position.
"Rich256" <nospam@nospam.net> wrote in message
news:_6UAf.523502$zb5.300197@bgtnsc04-news.ops.worldnet.att.net...
>
> "351CJ" <351CJ@msn.com> wrote in message
> news:6GTAf.4862$Le2.3199@trnddc04...
>>
>> "Rich256" <nospam@nospam.net> wrote in message
>> news:T4PAf.284842$qk4.198687@bgtnsc05-news.ops.worldnet.att.net...
>> >
>> > "Nehmo" <nehmo54@hotmail.com> wrote in message
>> > news:1137895163.229965.28440@z14g2000cwz.googlegroups.com...
>> >> "Pull-behind" trailers are trailers that connect to the tow
>> >> vehicle by
>> >> a ball (or other attaching arrangement) on the back of tow vehicle
>> >> and
>> >> a trailer hitch on the tongue attached to the front of the frame
>> >> of the
>> >> trailer. If the trailer is improperly-loaded into a tail-heavy
>> >> condition (in other words, the center of gravity is to the rear of
>> >> the
>> >> center of the axles) arrangement, it will sway from side to side.
>> >> But
>> >> why? Why would tail-heavy conditions cause such behavior? The
>> >> weight on
>> >> the tongue would be negative, but I still can't understand the
>> >> swaying
>> >> mechanism.
>> >> --
>> >> (||) Nehmo (||)
>> >
>> > Just having the weight behind the wheels in itself doesn't produce
>> > the
>> > sway.
>> > It allows amplification.
>> >
>> > Many things can get the sway started (wind, bumps in the road,
>> > passing
>> > vehicles) and once going the weight unbalance makes it more
>> > difficult to
>> > control.
>> >
>> > The trailer is like a pendelum hanging out behind the tow vehicle.
>> > The
>> > closer the weight is to the vehicle the easier it is to control.
>> > Try
>> > holding a board with a weight on it out in the wind. It's a lot
>> > easier
> to
>> > control if the weight is close in.
>> >
>> > The weight and length of the tow vehicle also comes into play.
>> > When a
>> > tail
>> > heavy pendelum starts to swing it will start controlling the tow
> vehicle.
>> >
>> > The flex of the tires adds more amplificaton.
>> >
>> >
>> > No matter what you do there is always possibility of sway. The
>> > amount
> of
>> > weight you put on the hitch is a compromise.
>> > Only total solution is to put all the weight on the tow vehicle and
>> > elimiate
>> > the trailer.
>> >
>> >
>>
>> By The Way,
>>
>> Amplification, this was the only reasonable response to your
>> question...
>>
>>
>
> Thinking about it a little more one could have a really long trailer
> that is
> very heavily loaded in the rear and you could pull it at very high
> speeds,
> with a short wheelbase vehicle, without any trouble. But only as long
> as
> there is no wind, no bumps or anything else to get it into a sway
> condition.
> But god help you if it begins to swing!!
>
> Nothing more frightening than having the trailer begin to do the
> steering.
>
>
And.... don't try putting the brakes on in an aggressive manner.
> "Rich256" <nospam@nospam.net> wrote in message
> news:_6UAf.523502$zb5.300197@bgtnsc04-news.ops.worldnet.att.net...
>
>>"351CJ" <351CJ@msn.com> wrote in message
>>news:6GTAf.4862$Le2.3199@trnddc04...
>>
>>>"Rich256" <nospam@nospam.net> wrote in message
>>>news:T4PAf.284842$qk4.198687@bgtnsc05-news.ops.worldnet.att.net...
>>>
>>>>"Nehmo" <nehmo54@hotmail.com> wrote in message
>>>>news:1137895163.229965.28440@z14g2000cwz.googlegroups.com...
>>>>
>>>>>"Pull-behind" trailers are trailers that connect to the tow
>>>>>vehicle by
>>>>>a ball (or other attaching arrangement) on the back of tow vehicle
>>>>>and
>>>>>a trailer hitch on the tongue attached to the front of the frame
>>>>>of the
>>>>>trailer. If the trailer is improperly-loaded into a tail-heavy
>>>>>condition (in other words, the center of gravity is to the rear of
>>>>>the
>>>>>center of the axles) arrangement, it will sway from side to side.
>>>>>But
>>>>>why? Why would tail-heavy conditions cause such behavior? The
>>>>>weight on
>>>>>the tongue would be negative, but I still can't understand the
>>>>>swaying
>>>>>mechanism.
>>>>>--
>>>>> (||) Nehmo (||)
>>>>
>>>>Just having the weight behind the wheels in itself doesn't produce
>>>>the
>>>>sway.
>>>>It allows amplification.
>>>>
>>>>Many things can get the sway started (wind, bumps in the road,
>>>>passing
>>>>vehicles) and once going the weight unbalance makes it more
>>>>difficult to
>>>>control.
>>>>
>>>>The trailer is like a pendelum hanging out behind the tow vehicle.
>>>>The
>>>>closer the weight is to the vehicle the easier it is to control.
>>>>Try
>>>>holding a board with a weight on it out in the wind. It's a lot
>>>>easier
>>
>>to
>>
>>>>control if the weight is close in.
>>>>
>>>>The weight and length of the tow vehicle also comes into play.
>>>>When a
>>>>tail
>>>>heavy pendelum starts to swing it will start controlling the tow
>>
>>vehicle.
>>
>>>>The flex of the tires adds more amplificaton.
>>>>
>>>>
>>>>No matter what you do there is always possibility of sway. The
>>>>amount
>>
>>of
>>
>>>>weight you put on the hitch is a compromise.
>>>>Only total solution is to put all the weight on the tow vehicle and
>>>>elimiate
>>>>the trailer.
>>>>
>>>>
>>>
>>>By The Way,
>>>
>>>Amplification, this was the only reasonable response to your
>>>question...
>>>
>>>
>>
>>Thinking about it a little more one could have a really long trailer
>>that is
>>very heavily loaded in the rear and you could pull it at very high
>>speeds,
>>with a short wheelbase vehicle, without any trouble. But only as long
>>as
>>there is no wind, no bumps or anything else to get it into a sway
>>condition.
>>But god help you if it begins to swing!!
>>
>>Nothing more frightening than having the trailer begin to do the
>>steering.
>>
>>
>
>
> And.... don't try putting the brakes on in an aggressive manner.
>
>
What do you mean reasonable response, I would stop her as soon as I
could, throw the anchor out and hope for two things, it hooks on
something big enough and the second thing is the chain does not break.
Junior wrote:
> "Rich256" <nospam@nospam.net> wrote in message
> news:_6UAf.523502$zb5.300197@bgtnsc04-news.ops.worldnet.att.net...
>
>>"351CJ" <351CJ@msn.com> wrote in message
>>news:6GTAf.4862$Le2.3199@trnddc04...
>>
>>>"Rich256" <nospam@nospam.net> wrote in message
>>>news:T4PAf.284842$qk4.198687@bgtnsc05-news.ops.worldnet.att.net...
>>>
>>>>"Nehmo" <nehmo54@hotmail.com> wrote in message
>>>>news:1137895163.229965.28440@z14g2000cwz.googlegroups.com...
>>>>
>>>>>"Pull-behind" trailers are trailers that connect to the tow
>>>>>vehicle by
>>>>>a ball (or other attaching arrangement) on the back of tow vehicle
>>>>>and
>>>>>a trailer hitch on the tongue attached to the front of the frame
>>>>>of the
>>>>>trailer. If the trailer is improperly-loaded into a tail-heavy
>>>>>condition (in other words, the center of gravity is to the rear of
>>>>>the
>>>>>center of the axles) arrangement, it will sway from side to side.
>>>>>But
>>>>>why? Why would tail-heavy conditions cause such behavior? The
>>>>>weight on
>>>>>the tongue would be negative, but I still can't understand the
>>>>>swaying
>>>>>mechanism.
>>>>>--
>>>>> (||) Nehmo (||)
>>>>
>>>>Just having the weight behind the wheels in itself doesn't produce
>>>>the
>>>>sway.
>>>>It allows amplification.
>>>>
>>>>Many things can get the sway started (wind, bumps in the road,
>>>>passing
>>>>vehicles) and once going the weight unbalance makes it more
>>>>difficult to
>>>>control.
>>>>
>>>>The trailer is like a pendelum hanging out behind the tow vehicle.
>>>>The
>>>>closer the weight is to the vehicle the easier it is to control.
>>>>Try
>>>>holding a board with a weight on it out in the wind. It's a lot
>>>>easier
>>
>>to
>>
>>>>control if the weight is close in.
>>>>
>>>>The weight and length of the tow vehicle also comes into play.
>>>>When a
>>>>tail
>>>>heavy pendelum starts to swing it will start controlling the tow
>>
>>vehicle.
>>
>>>>The flex of the tires adds more amplificaton.
>>>>
>>>>
>>>>No matter what you do there is always possibility of sway. The
>>>>amount
>>
>>of
>>
>>>>weight you put on the hitch is a compromise.
>>>>Only total solution is to put all the weight on the tow vehicle and
>>>>elimiate
>>>>the trailer.
>>>>
>>>>
>>>
>>>By The Way,
>>>
>>>Amplification, this was the only reasonable response to your
>>>question...
>>>
>>>
>>
>>Thinking about it a little more one could have a really long trailer
>>that is
>>very heavily loaded in the rear and you could pull it at very high
>>speeds,
>>with a short wheelbase vehicle, without any trouble. But only as long
>>as
>>there is no wind, no bumps or anything else to get it into a sway
>>condition.
>>But god help you if it begins to swing!!
>>
>>Nothing more frightening than having the trailer begin to do the
>>steering.
>>
>>
>
>
> And.... don't try putting the brakes on in an aggressive manner.
>
>
YOU DO NOT WANT TO VEHICLE BRAKES AT ALL WHEN THIS HAPPENS, TRAILER
BRAKES ONLY TO PULL OUT OF IT.
"TheSnoMan" <admin@snoman.com> wrote in message
news:TNxBf.5850$vU2.1421@newsread3.news.atl.earthlink.net...
> YOU DO NOT WANT TO VEHICLE BRAKES AT ALL WHEN THIS HAPPENS, TRAILER BRAKES
> ONLY TO PULL OUT OF IT.
>
> --
>
> -----------------
> www.thesnoman.com
