What a load of old tosh, and all over 2 mtrs…thats hardly saving is it. Why not use 2 trailers like Denby has but cant use…so heres my plan, at the beginning of every motorway, build hubs to take these giants…and have them at every major town along the route…all the towns would have smaller vehicles running back and forth to the hubs for onward delivery to the next hub or the hub nearest its destination, and dedicate the nearside lane of motorways purely for the double bottoms on a direct entry from the motorway, where they can drop their trailers and pick up 2 fresh ones, then you can save co2/emissions etc realistically.
Any better ideas, add to the post, but be sensible.
Crusaderrr:
DfT urged to bring longer semi-trailers into circulation
The safety claim seems tenuous?
“55% fewer…accidents… than average LGV”
I would expect longer trailers to be used more on motorways and main routes. Less on town centre, urban, or country lanes.
So if they are being used in this way, is the safety claim being weighted to account for this use? Comparing long distance trucks with shop deliveries and tippers ain’t good.
I remember ages ago dx freight had got some d/d trailers that were longer with the rear steer crap.
They later found out that quite a few of the depots couldn’t take them. Due to the extra size.
I do a lot of work with 16’ high LST Trailers (Since 2014). They seem to take some pulling compared to 45 footer, The fuel figures are usually quite poor compared to a 45 Footer. They are ok for trucking between depots but not much good for anything else.
Worst of all worlds combination of more load deck space at the expense of loads of extra tail sweep.But can’t carry any more weight and would just take loads of weight off the pin even if it could.It’s only any use for high volume low weight loads.Literally a useless waste of space.
As opposed to a proper Scandinavian 3 + 4 or 5 or NZ 4 + 4 drawbar outfit.
Carryfast:
Worst of all worlds combination of more load deck space at the expense of loads of extra tail sweep.But can’t carry any more weight and would just take loads of weight off the pin even if it could.It’s only any use for high volume low weight loads.Literally a useless waste of space.As opposed to a proper Scandinavian 3 + 4 or 5 or NZ 4 + 4 drawbar outfit.
Haven driven one a couple of times, they actually go around roundabouts much better, and they follow the road more, so don’t cut across as much or quickly as a normal triaxle.
Carryfast:
But can’t carry any more weight and would just take loads of weight off the pin even if it could.It’s only any use for high volume low weight loads.
Errrr, ain’t that the point of them? I mean, if you’re grossing out on a 45 footer why would you even want a longer trailer?
However if you’re cubing out before grossing out then surely that extra length is an overall benefit.
And as for taking weight off the pin I can’t see your reasoning with that. It’s not like they’re tacking the extra length on the back of a standard trailer. The ones I pulled had larger but equal distances between axles compared to a standard tri axle but had two rear steering axles. No issues whatsoever with weight coming off the pin and they followed the unit a lot better especially when turning right at roundabouts.
Here’s my old one
Permanent (no locking off) rear steer and weird axle placement it looks like some kind of fairground setup.
Reverses a bit like a dodgem aswell, just keep spinning the wheel and you will get it in eventually
It’s a pig to manoeuvre but nice on the roads.
Skirts get good mpg too
Johneboy:
Carryfast:
But can’t carry any more weight and would just take loads of weight off the pin even if it could.It’s only any use for high volume low weight loads.Errrr, ain’t that the point of them? I mean, if you’re grossing out on a 45 footer why would you even want a longer trailer?
However if you’re cubing out before grossing out then surely that extra length is an overall benefit.
And as for taking weight off the pin I can’t see your reasoning with that. It’s not like they’re tacking the extra length on the back of a standard trailer. The ones I pulled had larger but equal distances between axles compared to a standard tri axle but had two rear steering axles. No issues whatsoever with weight coming off the pin and they followed the unit a lot better especially when turning right at roundabouts.
I think you missed all my points.Firstly I said the extra length is only any good for extra volume not weight.
Bearing in mind that the cut in has to remain the same so the distance from pin to axles has to stay the same and a large part of the extra length is therefore behind the first and second axles.Which obviously means that even ‘if’ the extra length ‘was’ used to carry more weight, it would mean taking it off the pin and dropping it on the second and/or third trailer axles.
As for tail sweep rear steer axles are designed to go with it not stop it/reduce it.
Productivety is rightly generally measured in terms of tonne/miles.Which in the case of extra load deck space that can only take more volume not weight is obviously an under utilisation of road space and does nothing to improve tonne/miles/per gallon efficiency.
Unlike a proper LHV. 
Carryfast:
Johneboy:
Carryfast:
But can’t carry any more weight and would just take loads of weight off the pin even if it could.It’s only any use for high volume low weight loads.Errrr, ain’t that the point of them? I mean, if you’re grossing out on a 45 footer why would you even want a longer trailer?
However if you’re cubing out before grossing out then surely that extra length is an overall benefit.
And as for taking weight off the pin I can’t see your reasoning with that. It’s not like they’re tacking the extra length on the back of a standard trailer. The ones I pulled had larger but equal distances between axles compared to a standard tri axle but had two rear steering axles. No issues whatsoever with weight coming off the pin and they followed the unit a lot better especially when turning right at roundabouts.I think you missed all my points.Firstly I said the extra length is only any good for extra volume not weight.
Bearing in mind that the cut in has to remain the same so the distance from pin to axles has to stay the same and a large part of the extra length is therefore behind the first and second axles.Which obviously means that even ‘if’ the extra length ‘was’ used to carry more weight, it would mean taking it off the pin and dropping it on the second and/or third trailer axles.
As for tail sweep rear steer axles are designed to go with it not stop it/reduce it.
Productivety is rightly generally measured in terms of tonne/miles.Which in the case of extra load deck space that can only take more volume not weight is obviously an under utilisation of road space and does nothing to improve tonne/miles/per gallon efficiency.
Unlike a proper LHV.
This is one of the trailers I used to pull…
As you can see, the distance from the pin to the first axle is longer than on a standard trailer. It doesn’t have to stay in the same place. I understand how rear steers work as I use them every day and in this case they compensate for axle 1 been placed further to the rear of the trailer. If all axles were fixed, cut in would be horrendous. The rear steers push the back end out eliminating tyres fighting against each other, so drastically reducing cut in.
Axle spacing are greater and also equal because axles 2 and 3 both steer and in doing so need more space, therefore ‘if’ extra weight ‘could’ be added it still wouldn’t take weight off the pin.
As for your productivity argument, if you take it to the extreme would that mean you’re in favour of Australian type road trains delivering bog roll to rdc’s as to get the tons/mile? 
Johneboy:
This is one of the trailers I used to pull…
0As you can see, the distance from the pin to the first axle is longer than on a standard trailer.
Are you sure about that.Bearing in mind that not only doesn’t it look like it the law wouldn’t allow it because it would affect the cut in which has to remain the same.So as I said it’s compromised because anything behind that first axle starts to take weight off the pin and gets worse the further it goes back.So a waste of space on a tonne/mile/per gallon basis. 
Carryfast:
Johneboy:
This is one of the trailers I used to pull…
0As you can see, the distance from the pin to the first axle is longer than on a standard trailer.
Are you sure about that.Bearing in mind that not only doesn’t it look like it the law wouldn’t allow it because it would affect the cut in which has to remain the same.So as I said it’s compromised because anything behind that first axle starts to take weight off the pin and gets worse the further it goes back.So a waste of space on a tonne/mile/per gallon basis.
Yep. Quite sure. It ain’t much in the pic but I’ve seen it side by side to a standard tri.
The amount of cut in is reduced due to the steered axles. They push the back end out, steering it away from where it should cut in hence why it LST’s conform to inner and outer turning circle limits .
As for taking weight off the pin,how? The only way it would happen is if you were to put the heaviest parts of the load behind the first axle but the same’s still true of a normal trailer anyway
Johneboy:
Yep. Quite sure. It ain’t much in the pic but I’ve seen it side by side to a standard tri.
The amount of cut in is reduced due to the steered axles. They push the back end out, steering it away from where it should cut in
As for taking weight off the pin,how? The only way it would happen is if you were to put the heaviest parts of the load behind the first axle but the same’s still true of a normal trailer anyway
Only all 3 axles contra steering would make any difference to the cut in assuming a longer pin to axle measurement.If axle 1,or 1 and 2, is/are fixed then axles 2 and/or 3 can only steer around it not push it sideways.
It’s clear that most/all of the extra length on that trailer is behind axle 1.
The fact that dropping weight on the extra load deck space behind that axle removes weight from the pin in addition to the gross weight remaining the same, thereby making it a waste of space in terms of tonne/miles/per gallon, is my point.
Carryfast:
Johneboy:
Yep. Quite sure. It ain’t much in the pic but I’ve seen it side by side to a standard tri.
The amount of cut in is reduced due to the steered axles. They push the back end out, steering it away from where it should cut in
As for taking weight off the pin,how? The only way it would happen is if you were to put the heaviest parts of the load behind the first axle but the same’s still true of a normal trailer anywayOnly all 3 axles contra steering would make any difference to the cut in assuming a longer pin to axle measurement.If axle 1,or 1 and 2, is/are fixed then axles 2 and/or 3 can only steer around it not push it sideways.
It’s clear that most/all of the extra length on that trailer is behind axle 1.
The fact that dropping weight on the extra load deck space behind that axle removes weight from the pin in addition to the gross weight remaining the same, thereby making it a waste of space in terms of tonne/miles/per gallon, is my point.
CF you are so out of touch the rear does steer and push to the other side reducing cut in so much so it will hit obstacles on the other side, and weight distribution is the same as any artic don’t get involved in stuff you know nothing about
robthedog:
Carryfast:
Johneboy:
Yep. Quite sure. It ain’t much in the pic but I’ve seen it side by side to a standard tri.
The amount of cut in is reduced due to the steered axles. They push the back end out, steering it away from where it should cut in
As for taking weight off the pin,how? The only way it would happen is if you were to put the heaviest parts of the load behind the first axle but the same’s still true of a normal trailer anywayOnly all 3 axles contra steering would make any difference to the cut in assuming a longer pin to axle measurement.If axle 1,or 1 and 2, is/are fixed then axles 2 and/or 3 can only steer around it not push it sideways.
It’s clear that most/all of the extra length on that trailer is behind axle 1.
The fact that dropping weight on the extra load deck space behind that axle removes weight from the pin in addition to the gross weight remaining the same, thereby making it a waste of space in terms of tonne/miles/per gallon, is my point.
CF you are so out of touch the rear does steer and push to the other side reducing cut in so much so it will hit obstacles on the other side, and weight distribution is the same as any artic don’t get involved in stuff you know nothing about
Exactly.
CF I know it doesn’t matter what I say to you in regards to how the trailers behave because I know you’ve already made your mind up, and as everyone on here knows, once your mind is made up it won’t be changed, whether you’re right or wrong
To further prove my point, I did go to the same rdc with both a standard trailer and a LST. The final roundabout was a right turn. With a normal trailer you had to ‘pinch’ a bit of the left lane going around or else the trailer wheels would mount the roundabout kerb. With the LST you could keep to your own lane all the way round. That was how effective the rear steers were in reducing cut in , they track better than a standard trailer. Fact.
And the first axle was placed further back
Carryfast:
I think you missed all my points.
Nope, no we didn’t miss them…
We intentionally ignore them…
robthedog:
CF you are so out of touch the rear does steer and push to the other side reducing cut in so much so it will hit obstacles on the other side, and weight distribution is the same as any artic don’t get involved in stuff you know nothing about
As I said unless ‘all’ three steer then axles 2 and/or 3 ‘steering’ can’t possibly ‘push’ the fixed axle 1 anywhere. You’re obviously confusing tail sweep/swing with a proper STGO rear steer set up.Unless it’s STGO then standard pin to axle and resulting cut in rules apply.All you’ve got is increased tail sweep and an obviously longer load deck length behind trailer axles one and two which also means a totally different weight distribution regime.
Reef:
Carryfast:
I think you missed all my points.Nope, no we didn’t miss them…
We intentionally ignore them…
Some might call it ignorance.It’s clear that in no case is any length added between the pin and first trailer axle.( Which is fixed ).It’s just a compromised load deck space at the expense of tail sweep design.
Isnt the rear axle positively steered? If so this would push the rear round reducing the scrub on the other two axles.