Allan,the three points you,ve just made are very fair,i agree with all of them.and safty is at the top of the tree.with out talking we,d get nowhere,and its good to hear other peoples points.
Allan, I would also endorse all three points you have made.
As regards it falling on deaf ears at no point during the length of this thread has anyone suggested carrying out or suggested anything unsafe action.
It is good that you obviously take safety seriously as I can asure you I do. As do others contributing to this thread as has been apparent from their input into this forum over the years.
However I would add that you appear to be to self opionated to take time to understand what others are saying.
As regards it falling on deaf ears at no point during the length of this thread has anyone suggested carrying out or suggested anything unsafe action.
It is good that you obviously take safety seriously as I can asure you I do. As do others contributing to this thread as has been apparent from their input into this forum over the years.
However I would add that you appear to be to self opionated to take time to understand what others are saying.
And of course it would seem the only real life test to be carried out showed that a car with abs towing a caravan stopped quicker than a car with abs solo.
I have mags going back many years and when I have time I will see if I can find the artical although I have had a clear out on a couple of occations so it may not be there. From memory I would say it wasn't either of the clubs and I'm sure it wasn't PCM, so that leaves either Caravan or Caravan Life.
Brian (",)
I have mags going back many years and when I have time I will see if I can find the artical although I have had a clear out on a couple of occations so it may not be there. From memory I would say it wasn't either of the clubs and I'm sure it wasn't PCM, so that leaves either Caravan or Caravan Life.
Brian (",)
Thank you Lutz, when you say the weight of the vehicle is not Increased, I'm not splitting hairs but normally when we all take our caravan's on holiday we normally take everything apart from the kitchen sink, thus the increased weight on the car + the towed trailer, it therefore makes for best practice if we allow for a greater braking distance. And to all those out there who are adding there bit and seem to be getting there knickers in a twist, this is not a personal attack on Lutz, just a difference of opinion, I am certain that he is a very knowledgeable chap, and I therefore resent being called self opinionated when I am trying to get across a health and safety related topic
Noting Brian St A's post.
"car with abs towing a caravan stopped quicker than a car with abs solo"
So is it QUICKER or SHORTER ? ;-)
It's just that during this debate whilst searching for data I've come across many warnings from around the world saying that ABS is not a guarantee of shorter braking distances when solo as in many cases it can extend braking distances as it aids the ability to steer rather than skid.
A number of theses warnings are given by our own Police forces and others.
"car with abs towing a caravan stopped quicker than a car with abs solo"
So is it QUICKER or SHORTER ? ;-)
It's just that during this debate whilst searching for data I've come across many warnings from around the world saying that ABS is not a guarantee of shorter braking distances when solo as in many cases it can extend braking distances as it aids the ability to steer rather than skid.
A number of theses warnings are given by our own Police forces and others.
Brian, I think the article was in Caravan magazine. Unfortunatly I don't tend to keep back copies for much more than six months these days.
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My comparison was always between a fully laden car and a fully laden car towing a caravan. So, the argument really boils down to whether or not the increased braking efficiency of the rear brakes of the car when towing PLUS the braking efficiency of the caravan's brakes are or are not more than capable of stopping just the weight of the caravan. My data claims this is the case, Allan says no. So, we'll just have to compare the details and find out the reason for the discrepancy.
I would read it as one of the same thing Cris, if it takes a shorter distance to stop, then I would think the stopping time would be quicker, & vise versa 
Are we any nearer closure?
I have a lousy cold & all this is taking its toll (& like a fool we went away in the van for the week-end)....... lol.
No I do not expect sympathy, just take me outside in front of the firing squad.
(Just trying to get it back on a light-hearted footing)
Allan.
Are we any nearer closure?
I have a lousy cold & all this is taking its toll (& like a fool we went away in the van for the week-end)....... lol.
No I do not expect sympathy, just take me outside in front of the firing squad.
(Just trying to get it back on a light-hearted footing)
Allan.
So may be someone would like to comment on this press reporting ;-)
"Brakes: Most caravans and trailers these days have brakes, smaller ones may not, but usually as long as you matched your tow car right, they don't need them. However, don't be mislead, the brakes on caravans etc, are 'over-run' brakes. I.e., they are designed to slow it down, NOT stop it. Usually the brakes are of drum type, like those found on the back wheels of most cars. They are operated by the tow hitch, as the car slows down the caravan pushes against the tow bar, the hitch has a hydraulic (usually) ram in it and as the caravan pushes it pushes the ram in which in turn, applies the brakes. Their main function is to help stop the caravan running away with you, and keeps it at the cars speed as well as assist the cars brakes in stopping. However in an emergency they are almost ineffective and you are mainly relying on your cars brakes.
So when towing, you have to allow yourself twice the stopping distance, and follow other cars twice as far behind, because no matter how fast you can apply the brakes, or what fancy electronics you have on your car, you are going to need at least twice the stopping distance. "
"Brakes: Most caravans and trailers these days have brakes, smaller ones may not, but usually as long as you matched your tow car right, they don't need them. However, don't be mislead, the brakes on caravans etc, are 'over-run' brakes. I.e., they are designed to slow it down, NOT stop it. Usually the brakes are of drum type, like those found on the back wheels of most cars. They are operated by the tow hitch, as the car slows down the caravan pushes against the tow bar, the hitch has a hydraulic (usually) ram in it and as the caravan pushes it pushes the ram in which in turn, applies the brakes. Their main function is to help stop the caravan running away with you, and keeps it at the cars speed as well as assist the cars brakes in stopping. However in an emergency they are almost ineffective and you are mainly relying on your cars brakes.
So when towing, you have to allow yourself twice the stopping distance, and follow other cars twice as far behind, because no matter how fast you can apply the brakes, or what fancy electronics you have on your car, you are going to need at least twice the stopping distance. "
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I don't doubt that caravan brakes are not as powerful as car brakes but then car brakes have to cater for much more severe conditions, such as repeated stops, higher speeds, etc. However, under certain conditions, caravan brakes are still able to lock up the wheels, even on a dry road surface, so they can't be that bad.
I would think that the caravan's brakes are not always more than capable of stopping the van, as stated before they are there to assist in the stooping of the outfit, and it has also been pointed out that Drum Brakes tend to over heat and fade under extreme braking. This could happen, for example, if the caravan's brakes have faded, such as on a long descent,(not my words) thus one of the reasons that I advocate to allow for a longer stopping distance, better safe than sorry.
Allan.
Allan.
That being the case then Lutz.
You then have to agree that a lot more force from the vans weight transfers to the car at times.
As so many other factors from tyre grip/type/pressure to road surface type and conditions and more effect braking I believe Shorter / Quicker braking with caravan in tow and ABS equipped car may only occur under very ideal sittuations.
You then have to agree that a lot more force from the vans weight transfers to the car at times.
As so many other factors from tyre grip/type/pressure to road surface type and conditions and more effect braking I believe Shorter / Quicker braking with caravan in tow and ABS equipped car may only occur under very ideal sittuations.
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Oh dear, we really are going round in circles now. Of course, there is a force transfer from the caravan to the car. However, the vertical component of that force assists the rear brakes. Whether this is more than sufficient to offset the horizontal component which is trying to push the car forward is something that only an analysis of the ROSPA and other data will tell us. Don't let us surmise anything that neither of us can prove but let's wait for the details.
Lutz. Allthough you are right in one way about the downforce.
If caravanbbraking is degraded the downward force will not only change to forward force but also lift as well as the cars nose dips without full braking lift will be generated to the rear of the car!
There are dozens of scientific based reports re caravan braking yet no where around the world can I find one thing relating to shorter braking distance.
I don't doubt the report, but it just can not be a blanket indication that you will stop in shorter towing a caravn with a ABS tow car.
A good driver can out brake ABS if he is good at Cadence braking after all. But you have to be GOOD and well skilled.
If caravanbbraking is degraded the downward force will not only change to forward force but also lift as well as the cars nose dips without full braking lift will be generated to the rear of the car!
There are dozens of scientific based reports re caravan braking yet no where around the world can I find one thing relating to shorter braking distance.
I don't doubt the report, but it just can not be a blanket indication that you will stop in shorter towing a caravn with a ABS tow car.
A good driver can out brake ABS if he is good at Cadence braking after all. But you have to be GOOD and well skilled.
Lutz.
Many cars rear ends gain lift from caravans in accident or emergancy sittuations.
The force/energy will take the least line of resistance, apart from staged accident film I saw some years ago I've even seen a largish estate car that ended up with its rear end and the caravan tow bar over the centre motoway armco.
As the car hit the soft central reservation and the front dug in the Caravans rear end went town and the front lifted the car as it slid in a jack knife position helping it climb the armco.
Many cars rear ends gain lift from caravans in accident or emergancy sittuations.
The force/energy will take the least line of resistance, apart from staged accident film I saw some years ago I've even seen a largish estate car that ended up with its rear end and the caravan tow bar over the centre motoway armco.
As the car hit the soft central reservation and the front dug in the Caravans rear end went town and the front lifted the car as it slid in a jack knife position helping it climb the armco.
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If the car comes to an abrupt stop due to impact in the event of an accident the caravan could lift the back end, yes. However, to make this possible, the couple generated between the horizontal force acting on the towball and its height over the point of impact (front wheels digging into the ground or maybe hitting a kerb, for example) would have to be sufficient to lift the car bodily. This would really only occur in a severe accident experiencing very high impact forces. Normally, though, during braking, adhesion between the car's tyres and the road will be nowhere near as great as to allow that to happen. Even an outfit with inoperative brakes on the caravan would not push so hard on the car but just skid to a halt.
Usually, if you see the back end of a car lifted up by the caravan after an accident, this is not due to braking in a straight line but after the outfit has jack-knifed, and that's a completely different kettle of fish. The only way jack-knifing can occur if the outfit is forced to brake while travelling in a straight line is if there is an enormous difference in tyre adhesion between left and right hand side, such as emergency braking while passing through a puddle of water or hitting ice on one side only.
If we leave the situation of braking in a straight line, things get so complex that almost anything can happen.
Usually, if you see the back end of a car lifted up by the caravan after an accident, this is not due to braking in a straight line but after the outfit has jack-knifed, and that's a completely different kettle of fish. The only way jack-knifing can occur if the outfit is forced to brake while travelling in a straight line is if there is an enormous difference in tyre adhesion between left and right hand side, such as emergency braking while passing through a puddle of water or hitting ice on one side only.
If we leave the situation of braking in a straight line, things get so complex that almost anything can happen.
I guess I've been a biker and driver for to long Lutz.
When I ride abike I expect and cars others to pull out on me and the unexpected to happen.
I expect lorries and other motorists to pull into the gap I leave when towing with no warning, the last thing I expect is for everything to go to a plan or formula should something make me take evasive action when towing.
I expect the stabiliser to be useless the caravan brakes not to work as they should and for the road to be wet bumpy with pot holes and a liberal coating of diesel.
That said, I don't crawl along when towing or sit awaiting disaster if you understand me.
Your post suggest you expect text book behaviour should you encounter a problem.
Other countries even have regulations re maintaining a gap between you and a vehicle in front when towing, this I believe is due to unpredictable braking when towing.
When I ride abike I expect and cars others to pull out on me and the unexpected to happen.
I expect lorries and other motorists to pull into the gap I leave when towing with no warning, the last thing I expect is for everything to go to a plan or formula should something make me take evasive action when towing.
I expect the stabiliser to be useless the caravan brakes not to work as they should and for the road to be wet bumpy with pot holes and a liberal coating of diesel.
That said, I don't crawl along when towing or sit awaiting disaster if you understand me.
Your post suggest you expect text book behaviour should you encounter a problem.
Other countries even have regulations re maintaining a gap between you and a vehicle in front when towing, this I believe is due to unpredictable braking when towing.
At long last we are finally getting there; expect the worst and you will be well and truly prepared. All types of vehicles require different driving techniques, none more so than a car towing a caravan, I personally can never relax whilst towing, as I have said many times before during these posts, they are the most unpredictable combination on our roads today, and thus demand total and utter respect and concentration at all times. Don't forget on Britain's overcrowded roads we have far from ideal driving conditions, so don't ever expect to get a text book stop under emergency braking, or any other braking, there are to many variables to take in to consideration. The only time I enjoy the caravan is when all four legs are down, and the only thing that I have to consider stopping, is me drinking to much beer.
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Yes, at last we are getting there. As avoiding action is more difficult and riskier when towing, it is advisable to keep a greater distance ahead of you but not because of braking in a straight line. In all the replies I made, I never said anything to contradict this statement.
I never suggested that you did, I would always advocate a greater distance between you and the vehicle in front, whether in a straight line or otherwise. The question I originally raised was to the statement you made re it is a proven fact that braking distance is actually shorter when towing a trailer than when the car is solo, and I found that to be a misleading blanket statement for the reasons that have been mentioned so many times in this thread.
Allan.
Allan.
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I'm sorry if you understood my replies to be blanket statements. They were never meant to be. All I intended to get over was that in a straight line and on a dry road, with all brakes working correctly, a fully laden car fitted with ABS and towing a caravan would be able to stop in a shorter distance than the same fully laden car not towing. Anything that deviates from these conditions could, under adverse circumstances (such as having to swerve at the same time to avoid a hazard for example) have the opposite effect.
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