Local lad killed by towball

[bblaze]

An 18 year old smithton lad has been killed by a towball, sitting in the back seat while a recovery was taking place.
Timely reminder to all to follow safe recovery methods
blaze

[Sprint]

there'll allways be argument over this......

[pop058]

An 18 year old smithton lad has been killed by a towball, sitting in the back seat while a recovery was taking place.
Timely reminder to all to follow safe recovery methods
blaze

Smithton man killed in freak accident - Local News - News - Disasters & Accidents - The Examiner Newspaper (http://www.examiner.com.au/news/local/news/disasters-accidents/smithton-man-killed-in-freak-accident/1640077.aspx)

[weeds]

there'll allways be argument over this......

no argument here.....

sad news indeed

and i reckon i will see a few towball recoveries on fraser next week as well

[Graeme]

The article mentions tow-ball, tow-bar and towing assembly, so not necessarily a broken tow-ball. However bad news whichever broke free.

[Lotz-A-Landies]

C'mon guys how many times have we seen pics of tow balls embedded in bonnets, or through screens. The last one I remember on here was a ball in the tailgate of a champaign coloured 100 Series.

It happens all the time just luckily, they don't always kill people. More importantly it is something that needs to be stamped out, if you see it about to happen, stop it, if they won't stop tell them you no longer wish to continue the trip or go on others with them because of their lack of safe recovery techniques.

Maybe it'll get the message out, maybe it won't but there are people (even on here) that I would never want to be within a kilometre of one of their recoveries. They probably know who they are.

Diana

[scarry]

and i reckon i will see a few towball recoveries on fraser next week as well


Your right there.....

Junior scarry saw a couple last week up there,they wouldnt listen.

They will never learn.

I knew a guy years ago who was killed on Moreton island,pulling his beloved Defender that was bogged ,with a tractor,some others on here may also have known him as well.

[dmdigital]

Half the problem is the fact there are no real recovery points on most standard 4WD's. People then put a tow bar on and hey-presto "Oh look a recovery point!" appears due to lack of understanding of the consequences. It should almost be mandatory to have a recovery receiver in any tow bar on a 4WD that is to go off-road.

[Bushie]

Half the problem is the fact there are no real recovery points on most standard 4WD's. .................................................. ...... It should almost be mandatory to have a recovery receiver in any tow bar on a 4WD that is to go off-road.

That's the problem 90% (probably more and Land Rovers included) will never leave the blacktop.

I'll admit, I've done my share of tow ball recoveries, am I lucky ? don't know, but 30 years ago probably no one was aware of the inherent dangers, after all snatch straps were only just starting to appear.


Martyn

[LandyAndy]

A towball can be used safely for a recovery if no other method of attatchment is available on most 4x4s.
Its simply a matter of using ones brains.You loop the snatch strap around the towbar before hooking onto the ball,the bar then takes the strain,if the ball is to fail the direction of any travel will be into the rear of the towing vehicle not towards the vehicle being recovered.
Andrew

[Cap]

Tragic for the family and friends, another young life lost :( :mad:

[slug_burner]

The flying towball often gets mentioned with snatch strap incident. The really dangerous bit of equipment is the snatch strap.

Too ealy to say but the article from Tasmania talks about the towing assembly and other bits as well as the ball. The one common item here is the snatch strap. Snatch straps need a big warning and perhaps buyers should be licenced to use them.

The towball is rated to 3500 kg as a max towing weight. Including a suitable safety factor on top of the acceleration/deceleration force when the trailer pushes against the towball (reduced with braked trailers) and the ball should be able to handle significantly more. Have a look on the front of 4wds that have lifting eyes on the bullbar. What are they rated to? Are you any better off using them to recover with?

[willem]

Perhaps what would be useful is for someone with real expertise in this area to write an article, with pics, demonstrating how to recover a vehicle that does not have a specialist recovery point fitted. They are the vehicles most likely to get into trouble, and are the least prepared for it.

If such an article already exists, it might be useful to have a link to it.

Moderators, might it be worthwhile having a 'table of contents' page with links to such resource articles that are either part of this forum or on other useful websites?

Willem

[TheLowRanger]

The flying towball often gets mentioned with snatch strap incident. The really dangerous bit of equipment is the snatch strap.

Too ealy to say but the article from Tasmania talks about the towing assembly and other bits as well as the ball. The one common item here is the snatch strap. Snatch straps need a big warning and perhaps buyers should be licenced to use them.

The towball is rated to 3500 kg as a max towing weight. Including a suitable safety factor on top of the acceleration/deceleration force when the trailer pushes against the towball (reduced with braked trailers) and the ball should be able to handle significantly more. Have a look on the front of 4wds that have lifting eyes on the bullbar. What are they rated to? Are you any better off using them to recover with?
Not all tow balls are rated, and of those that are, not all are rated for 3500kg. A lot of the cheaper tow balls don't have a rating, along with a lot of the older ones. The majority of 4wds have a hitch receiver type towbar, remove the hitch, put the strap through the receiver and use the pin to locate it. I have seen bent pins before, but never heard of one snapping. If it did happen to snap both sides of the pin would still be stuck in the receiver and only the strap would fly out. A strap on its own is not particularly lethal, but attach a solid object to the end of it and it's a whole different ball game. If I had a towbar that wasn't a receiver type, I personally would be removing the towball and then inserting a rated shackle through the hole to attach to. Even a 3.2T rated shackle will not self destruct until more than 16T of force has been applied to it.

[mark2]

Not all tow balls are rated, and of those that are, not all are rated for 3500kg. A lot of the cheaper tow balls don't have a rating, along with a lot of the older ones. The majority of 4wds have a hitch receiver type towbar, remove the hitch, put the strap through the receiver and use the pin to locate it. I have seen bent pins before, but never heard of one snapping. If it did happen to snap both sides of the pin would still be stuck in the receiver and only the strap would fly out. A strap on its own is not particularly lethal, but attach a solid object to the end of it and it's a whole different ball game. If I had a towbar that wasn't a receiver type, I personally would be removing the towball and then inserting a rated shackle through the hole to attach to. Even a 3.2T rated shackle will not self destruct until more than 16T of force has been applied to it.

ARB and others sell a solid recovery insert for the reciever which is designed to take a shackle. I have one (didnt pay for it and will probably never use it) and it would have to be significantly heavier than a towball, not including the shackle. I don't know if receiver pins are 'rated' either (never seen any evidence of such). Without doing the sums, and assuming similar metallurgy, would suspect a towball in single shear has a greater capacity than a receiver pin which is loaded in double shear due to much greater section size. Howeve the consequences of towball failure are probably greater, (unless you use the ARB insert)

I also think half the problem is people overestimate the amount of force needed in many recoveries and take much more of a run-up than is necessary.

[Pedro_The_Swift]

I also think half the problem is people overestimate the amount of force needed in many recoveries and take much more of a run-up than is necessary.


yep,,

if towing, just drive off.

[Andy-M]

Such a sad loss, I doubt people would have been thinking clearly about where they were recovering from that early in the morning.

A hard lesson learnt about recovery points and 4 wheel driving.

Blaze sorry to hear, your community has more than its share of tragedy involving young people.



Andy

[Debacle]

ARB and others sell a solid recovery insert for the reciever which is designed to take a shackle. I have one (didnt pay for it and will probably never use it) and it would have to be significantly heavier than a towball, not including the shackle. I don't know if receiver pins are 'rated' either (never seen any evidence of such). Without doing the sums, and assuming similar metallurgy, would suspect a towball in single shear has a greater capacity than a receiver pin which is loaded in double shear due to much greater section size. Howeve the consequences of towball failure are probably greater, (unless you use the ARB insert)

I also think half the problem is people overestimate the amount of force needed in many recoveries and take much more of a run-up than is necessary.

That last sentence says it all. Most think that they are using the snatch strap to pull the vehicle out whereas what you should be trying to do is to put enough stretch into the strap for it to do its work on its own using your vehicle as the anchor.

Perhaps a training video should be provided with purchase of these straps.

[whitakerb]

Maybe it'll get the message out, maybe it won't but there are people (even on here) that I would never want to be within a kilometre of one of their recoveries. They probably know who they are.




I also think half the problem is people overestimate the amount of force needed in many recoveries and take much more of a run-up than is necessary.




Perhaps a training video should be provided with purchase of these straps.

So the point here is people don't know what they are doing. I think we all need to go back to basics, i.e.
* No recovery points = goodbye,
* Take it easy, use the minimal force required
* Gloves whilst handling your rated and maintained recovery gear,
* Do not step over live recovery gear (attached at both ends), and most importantly;
* Keep all spectators well away during a recovery if they are not operating recovery gear or the vehicle they should be at the very least 1.5x the distance of the strap / Cable away from the vehicles.

Another thing to remember is for those of us who go on AULRO trips is that AULRO is not a 4wd Club and therefore has no public liability insurance if something goes wrong. I know that safety is paramount in any case, but if the worst happened because an AULROian did something like recover off a tow ball then the administrators could be liable???

As we represent an organization whilst on AULRO trips, we are required to do the right thing, so if you cant follow some simple rules, you have no place here.

Ben

4.9 RRC

[justinc]

A terrible loss, but totally preventable. incidents like this are really not 'freak accidents', they are just waiting to happen with incorrect recovery techniques.

Condolences to all feeling the loss.

JC

[d2dave]

Question,
I am doing a trip cup weekend. I have proper recovery points fitted to the front of my D1.
For the rear I am going to remove the tow ball and fit a rated shackle to the tow ball hole.
Is this OK? I saw it done in 4X4 Australia Magazine in an article demonstrating recovery technique.

Dave.

[weeds]

Question,
For the rear I am going to remove the tow ball and fit a rated shackle to the tow ball hole.
Is this OK? I saw it done in 4X4 Australia Magazine in an article demonstrating recovery technique.

Dave.

no worries there, i just removed my towball this afternoon as i am heading off to fraser island tomorrow and may need to pull somebody out of the sand......providing i don't get bogged

[d2dave]

What I find hard to comprehend is a tow ball rated to 3500kg is about the same as a rated shackle.

Dave.

[mark2]

Question,
I am doing a trip cup weekend. I have proper recovery points fitted to the front of my D1.
For the rear I am going to remove the tow ball and fit a rated shackle to the tow ball hole.
Is this OK? I saw it done in 4X4 Australia Magazine in an article demonstrating recovery technique.

Dave.

If you don't have the removable receiver type, this is probably your best option.
Otherwise, remove the insert and just use the pin to secure the strap.

[Sleepy]

Not a tow ball, but I once saw two snatch straps joined by a shackle. (Noooooo!!!) and then 2.5 tonnes of Nissan given the biggest run up I have ever seen for a snatch (10 to 20m - flat to the boards :eek2:). (I ran for the biggest tree I could find to stand behind.) Scary stuff indeed. Luckily the strap broke first on this occassion.


Nonetheless it is sad when we have a fatality and I shouldn't jump to conclusions. - It may just have been a tragic acccident.:(

[whitakerb]

What I find hard to comprehend is a tow ball rated to 3500kg is about the same as a rated shackle.

Dave.

I may be wrong, but a tow ball will be rated to tow a trailer that weighs up to 3500kg. but not necessarily take a 3500kg shock load and a 3.5T rated shackle will have a minimum breaking strain many time more than its SWL. JFYI the shackles we use in comp must be at the very least 4.75T and used in pairs with a bridal if possible so your looking at a breaking strain well in excess of 30T

Cheers

Ben

[101 Ron]

A few things I have noted.
I dont like snatch straps at all unless the towed vehicle is in a easy to recover situation.

The forces in snatch recoverys are not controlled.

People try to snatch vehicles bogged to the chassis rails and wonder why things break. ( work with a shovel and elbow greae is the better option)

Years ago before snatch straps people would use chains around tow balls etc and there was few probems as the chain did not tend to store energy if any thing broke.

If you try hard enough , just but any sort of recovery point will fail with a snatch strap.

People often forget what we used to do in the old days and crawl under vehicles and wrap a chain around the spring or axle assembly as most vehicles didnt have proper recovery points.(noting position of wires and brake lines)

Independant suspension vehicles can usually have a chain wrapped around the cross member under the motor or suspension lower anchor points.
Most people are too lazy to do the above and dig or crawl under the vehicle.

Using a winch the forces are known and easly controlled.

The dangerous part is the snatch strap and the reason they are so popular is they are cheap and much,much lighter than chains.

[p38arover]

..... 2.5 tonnes of Nissan given the biggest run up I have ever seen for a snatch (10 to 20m - flat to the boards :eek2:). (I ran for the biggest tree I could find to stand behind.) Scary stuff indeed. Luckily the strap broke first on this occassion.

When I was in the Toyota LC Club in Sydney, that is how I was taught to do a snatch recovery (well, not that long a run up but at close to the length of the snatch strap).

The first time I tried it, I snapped my new snatch strap - and with good reason. I was trying to recover this:

https://www.aulro.com/afvb/images/imported/2011/08/843.jpg


In retrospect, one can see it would be impossible to move by snatching - it should have been towed (it was later towed out). How heavy would it be with all that water inside it?

[rockyroad]

Its incidents like these that that I only go bush with other drivers that I trust and have something between their ears.

Doesn't help when you come across some turkey stuck on a popular track though, 9 times out of 10 dropping their tyre pressure and a shovel or some muscle will get them unstuck.

Makes you wonder whether a cargo barrier might have been enough to save the young blokes life?

[Andy-M]

A bit of info to clear up the guessing in relation to what occurred in the accident.

The vehicle the young lad was in was trying to snatch a vehicle from behind (reversing).

The tounge and square section that slides into the Hayman style receiver had been welded in the past. During the snatch the weld broke sending the tounge, ball and strap through the windscreen narrowly missing the driver, into the rear section where the lad was in the third row seat.

After hitting the lad it all continued smashing out the rear window. It had also come unhitched somehow from the front of the vehicle.

I hope this takes out the guess work and continues the discussion in relation to recovery points.



Andy

[Disco_Dan]

its a tragic thing to have happened and as has been said before it stresses the use for common sence , rated recovery gear and points , i like to winch rather than snatch unless all that is needed is a gentle pull like a tow , also making sure there is nobody in close proximity to whats going on especially inside the car besides the 2 drivers.. i suppose hindsight is a wonderful thing. but things like this happening are going to quickly destroy whatever privilages we have left as offroad enthusiests im sure many will agree.. Just my 2 cents. Dan.

[austastar]

Tas Fire service taught (if feasible) raising the bonnet on the Toyota if the line is out the front and the vehicle is occupied.
cheers

[Bushie]

Still no one has mentioned that (generally) the most useful piece of recovery gear is a shovel/spade and a bit of time spent digging. We continually see a hopelessly bogged 4WD try to be recovered by a big 'snatch' without any work to lessen the load.

Years ago I would regularly be recovering trucks, we used to tell the crew of the stuck vehicle to get on the end of a shovel while we made our way out to their location, and if they hadn't done enough digging sit there and wait while they did a whole lot more.


Martyn

[austastar]

Hi,
a U.S. Army manual I read (pdf on line) stated that a vehicle up to the sills in mud could require > 10x the vehicle weight to move it.
One could say 'that sucks'!
cheers

[whitakerb]

Hi,
a U.S. Army manual I read (pdf on line) stated that a vehicle up to the sills in mud could require > 10x the vehicle weight to move it.
One could say 'that sucks'!
cheers

Say for example my Rangie is up to its sills in mud and isn't going to go anywhere easily, suggesting as per US Army manual it will need approx 18T of force to remove from the hole

Snatch strap is attached to my Rangie and recovery vehicle with a 3500kg bow shackles.

If the recovery vehicle moves at walking pace and my maths are correct you will apply the following force on your gear.

For the sake of the argument, my Rangie is an immovable object and we are ignoring any other outside forces.

Mass = Recovery vehicle = 2000kg

Velocity = walking pace = 3km/h = 0.833333m/s

F = X KG

X= M*V

= 2000*0.83333 = 1666.66

Force = 1666.66KG

So not too much, but to overload the bow shackles we only need 3500kg of force;

F = 3500

M = 2000

V = F/M

3500/2000

1.75m/s = 6.3KM/H

So again if my maths are correct, you need to be doing 6.3km/h to overload a 3.5 T Bow shackle, however you are not likely to break it due to its safety factor which is IIRC 500% so 17.5T

Not much IMHO

Now say the Reece hitch was fully welded, and rule of thumb is 1 inch of weld will hold 1000kg then:

Reece hitch is 50x50mm = 8 inches of weld = 8000kg breaking strain, were not looking at a great deal of speed to create a lethal object.

If anything, make sure you pack your shovel next time so you can do the walking pace recoverys rather than trying warp speed to 'pop' it out of the bog

So condolences out to the victims family and hopefully it wakes us all up when on the tracks

[Sleepy]

Still no one has mentioned that (generally) the most useful piece of recovery gear is a shovel/spade and a bit of time spent digging. We continually see a hopelessly bogged 4WD try to be recovered by a big 'snatch' without any work to lessen the load.


Well said Bushie. I have bogged vehicles in sand and recovered on my hands and knees - clearing the sand by hand.

Using a shovel also lets you have a look at the situation, catch some fresh air (;)) and inspect the vehicle. The vehicle is often "hung up" by a rock, log, root etc. YOu can get an idea what is getting stuck (diff, gearbox, skid plate, etc) and whether something will be damaged in the snatch - including humans.

Thanks for the update Andy-M - it would have gone bad so very quickly :(

[Hymie]

Hi,
a U.S. Army manual I read (pdf on line) stated that a vehicle up to the sills in mud could require > 10x the vehicle weight to move it.
One could say 'that sucks'!
cheers


Read this,

http://www.aulro.com/afvb/general-chat/48111-winching-formulas.html

[303gunner]

When I was in the Toyota LC Club in Sydney, that is how I was taught to do a snatch recovery ......
The Suzuki 4wd club teaches the exact opposite. The most appropriate use of a snatch strap is where a vehicle is lightly stuck or has lost traction. The first attempt at recovery should have the tension taken up on the strap gently, then a constant tension used to tow the vehicle in the chosen direction while the driver drives out. If this fails to assist the bogged vehicle, only then should the second attempt use kinetic energy to extract the vehicle, and with as little "snatch" as necessary. This places the minimum stresses on components of both vehicles.

I remember at a 4wd Jamboree many years ago, I had bogged my Suzuki LJ50 (weighing a massive 900kg) and the duty recovery Landcruiser used the "Take off at max throttle with slack snatch strap" method. Not only did the LJ un-bog, it was nearly airborne and bent the front crossmember of the chassis. I very nearly got whiplash. I was ****ing furious and wanted to massage the Cruiser's driver with a pick handle. It would have been possible to have driven out of the mud with the assistance of 2 people pushing.

As others have said, if the vehicle is more heavily bogged, put away the snatch strap and use a Shovel, Tirfor or Winch.

[TheOtherLeft]

The Suzuki 4wd club teaches the exact opposite. The most appropriate use of a snatch strap is where a vehicle is lightly stuck or has lost traction. The first attempt at recovery should have the tension taken up on the strap gently, then a constant tension used to tow the vehicle in the chosen direction while the driver drives out. If this fails to assist the bogged vehicle, only then should the second attempt use kinetic energy to extract the vehicle, and with as little "snatch" as necessary. This places the minimum stresses on components of both vehicles.

I remember at a 4wd Jamboree many years ago, I had bogged my Suzuki LJ50 (weighing a massive 900kg) and the duty recovery Landcruiser used the "Take off at max throttle with slack snatch strap" method. Not only did the LJ un-bog, it was nearly airborne and bent the front crossmember of the chassis. I very nearly got whiplash. I was ****ing furious and wanted to massage the Cruiser's driver with a pick handle. It would have been possible to have driven out of the mud with the assistance of 2 people pushing.

As others have said, if the vehicle is more heavily bogged, put away the snatch strap and use a Shovel, Tirfor or Winch.

Just goes to show that not even the 4WD clubs teach/use the correct techniques.

[foz.in.oz]

refering back to whitakerb's maths I think the correct formula for force imparted by moving objects is in fact mass x velocity^2.

ie it is the square of the velocity which makes this even more nasty. Doubling the speed of the snatcher increases the force by 4 times.

Little steps are required going from no slack to small amount of slack in small increments. There are no medals for getting out of a bog on the first try.

Sometimes it is very difficult to stop people from going for it straight away though, and sometimes the onlookers don't help either. I got bogged once (out of many times) and breif the snatcher to take up the slack and then drive off gently as you would normally and some bogun half wit piped up saying "no mate, you want a decent run up and full noise". Thankfully the guy pulling maintained focus on me. Got me out with the most gentlist of pulss and I was up to the rails in river mud.

[slug_burner]

year 11 physics

Kenetic Energy (KE)= (1/2)m.v^2 Units are joules (or kg/sec^2)

Force = m.a Units are Newtons (or kg.m/sec^2)

When you use a snatch strap, you have the KE of the snatching vehicle as it has mass and velocity plus some potential energy which is stored in the elastic members of the snatch strap.

[d2dave]

year 11 physics

Kenetic Energy (KE)= (1/2)m.v^2 Units are joules (or kg/sec^2)

Force = m.a Units are Newtons (or kg.m/sec^2)

When you use a snatch strap, you have the KE of the snatching vehicle as it has mass and velocity plus some potential energy which is stored in the elastic members of the snatch strap.


Could you please translate this into something that some of us less educated can understand.

Dave.

[slug_burner]

Mr Whippy (Dave)

I hope your not pulling my leg.

Energy is measured in units of Joules. Work and energy are interchangeable and have the same units e.i., joules. Power is a measure of how quickly you can do work, the units of power are Newtons. Example: Given two vehicles of the same weight, one with a small engine and one with a bigger engine, they can both climb a hill and by the time they get to the top both have done the same amount of work. The one with the bigger engine should be able to get up the hill faster than the one with the small engine because it has a more powerfull motor. See here for another explanation (http://www.smpspowersupply.com/powerunits.html)

When people speak of energy, two types are often referred to i.e., Potential Energy and Kenetic Energy. Kenetic Energy is that associated with a moving body.

KE= 1/2 m. v^2 (said as "Kenetic Energy equals half m v squared) "m" is the symbol for mass and has units of kilos and "v" is the symbol for velocity and it has units of metres per second. All this means is that a moving mass has kenetic energy.

Potential Energy is used to express energy in bodies that are not moving. A streched spring or elastic although it might not be moving can store energy and that energy is referred to as potential energy. Energy can also be stored in a body by raising it in hieght (water in a tank raised above the ground, or stored in a dam)

F=m.a (said "Force equals m a") units are Newtons (Newton's Second Law of physics)

So what does that all mean? Power, force and energy are often used interchangeably in common speech but in fact are different. And, when you use a snatch strap not only do you use the kenetic energy of the towing vehicle to do work to pull the bogged vehicle out but you also have stored some potential energy in the snatch strap to help add more energy to pull the vehicle out.






Looking back over the previous equations in the other post I left the metres out of the the units of velocity

Kenetic Energy (KE)= (1/2)m.v^2 Units are joules (or kg m^2/sec^2)





Here is some further explanations (http://auto.howstuffworks.com/auto-parts/towing/towing-capacity/information/fpte.htm)


Force

[whitakerb]

Does that mean I'm right??
I thought i sounded smart with all my formulas and numbers but....

Don't suppose any of us who paid attention in physics could do some number crunching and give us the correct answer to my hypothesi? (plural??) Either way I'm glad I got some brains thinking away


Ben

[slug_burner]

whitakerb,

Are you correct? You ask. Yes and No. I think that most people have a reasonable understanding of what is happening in a recovery situation. School boy physics only takes us so far as there are many factors that we do not have values for. Even the REME or RAEME recovery book has some assumptions in order to determine what the resistance of mud, sand etc are and one lot of mud will be different to another. It them becomes difficult to work things out to any great accuracy. Some of the bits in red below need further clarification which I have tried to do.


Say for example my Rangie is up to its sills in mud and isn't going to go anywhere easily, suggesting as per US Army manual it will need approx 18T of force to remove from the hole

Snatch strap is attached to my Rangie and recovery vehicle with a 3500kg bow shackles.

If the recovery vehicle moves at walking pace and my maths are correct you will apply the following force on your gear.

For the sake of the argument, my Rangie is an immovable object and we are ignoring any other outside forces.

Mass = Recovery vehicle = 2000kg

Velocity = walking pace = 3km/h = 0.833333m/s

F = X KG F = m.a apart from the mass (m) we need a rate of change of velocity or acceleration (a) to calculate a force.

X= M*V momentum = m.v to change the velocity of a body you need to apply a force (Newton's 1st law)

= 2000*0.83333 = 1666.66

Force = 1666.66KG

So not too much, but to overload the bow shackles we only need 3500kg of force;

F = 3500

M = 2000

V = F/M

3500/2000

1.75m/s = 6.3KM/H

So again if my maths are correct, you need to be doing 6.3km/h to overload a 3.5 T Bow shackle, however you are not likely to break it due to its safety factor which is IIRC 500% so 17.5T

Not much IMHO

Now say the Reece hitch was fully welded, and rule of thumb is 1 inch of weld will hold 1000kg then:

Reece hitch is 50x50mm = 8 inches of weld = 8000kg breaking strain, were not looking at a great deal of speed to create a lethal object.

If anything, make sure you pack your shovel next time so you can do the walking pace recoverys rather than trying warp speed to 'pop' it out of the bog

So condolences out to the victims family and hopefully it wakes us all up when on the tracks

[austastar]

Hi,
I did a fairly extensive search to try and find the ref to 10x vehicle weight and dammed if I can find it.
From memory it was in a table of ground surfaces and rolling resistance factors, so I may have stuffed up with the 'weight'. It may have been 10x rolling resistance, BUT I think force to break suction was mentioned.
Just not sure of it now.
I guess the speed of extraction would have a lot to do with loading the forces required to move a bogged vehicle too.
As mentioned else where here, there would be heaps of variables in trying to get a handle on any maths involved.
cheers

[whitakerb]

whitakerb,

Are you correct? You ask. Yes and No. I think that most people have a reasonable understanding of what is happening in a recovery situation. School boy physics only takes us so far as there are many factors that we do not have values for. Even the REME or RAEME recovery book has some assumptions in order to determine what the resistance of mud, sand etc are and one lot of mud will be different to another. It them becomes difficult to work things out to any great accuracy. Some of the bits in red below need further clarification which I have tried to do.

Yes that makes more sence. I was thinking about it last night, and my formula was wrong, so to hypothesize about an answer you would need to work out the acceleration (deceleration) on the recovery vehicle as the strap took strain.

Force = Mass X Acceleration


Cheers

[mark2]

Mr Whippy (Dave)

I hope your not pulling my leg.

Power is a measure of how quickly you can do work, the units of power are Newtons.
Force (http://en.wikipedia.org/wiki/Force)

I thought the units of power are Watts??? (1 Watt = 1 Joule/second)

[d2dave]

Mr Whippy (Dave)

I hope your not pulling my leg.

Energy is measured in units of Joules. Work and energy are interchangeable and have the same units e.i., joules. Power is a measure of how quickly you can do work, the units of power are Newtons. Example: Given two vehicles of the same weight, one with a small engine and one with a bigger engine, they can both climb a hill and by the time they get to the top both have done the same amount of work. The one with the bigger engine should be able to get up the hill faster than the one with the small engine because it has a more powerfull motor. See here for another explanation (http://www.smpspowersupply.com/powerunits.html)

When people speak of energy, two types are often referred to i.e., Potential Energy and Kenetic Energy. Kenetic Energy is that associated
with a moving body.

KE= 1/2 m. v^2 (said as "Kenetic Energy equals half m v squared) "m" is the symbol for mass and has units of kilos and "v" is the symbol for velocity and it has units of metres per second. All this means is that a moving mass has kenetic energy.

Potential Energy is used to express energy in bodies that are not moving. A streched spring or elastic although it might not be moving can store energy and that energy is referred to as potential energy. Energy can also be stored in a body by raising it in hieght (water in a tank raised above the ground, or stored in a dam)

F=m.a (said "Force equals m a") units are Newtons (Newton's Second Law of physics)

So what does that all mean? Power, force and energy are often used interchangeably in common speech but in fact are different. And, when you use a snatch strap not only do you use the kenetic energy of the towing vehicle to do work to pull the bogged vehicle out but you also have stored some potential energy in the snatch strap to help add more energy to pull the vehicle out.






Looking back over the previous equations in the other post I left the metres out of the the units of velocity

Kenetic Energy (KE)= (1/2)m.v^2 Units are joules (or kg m^2/sec^2)





Here is some further explanations (http://auto.howstuffworks.com/auto-parts/towing/towing-capacity/information/fpte.htm)


Force (http://en.wikipedia.org/wiki/Force)

No I am not pulling your leg.
I do understand all about Kinetic and potential energy.

What I didn't understand and still don't is how to interpret the formula.

Your original post had this,

Kinetic Energy (KE)= (1/2)m.v^2 Units are joules (or kg/sec^2)

Force = m.a Units are Newtons (or kg.m/sec^2)


Ok the (KE) means Kinetic Energy.

(1/2)m I assume means half the mass. Why is the 1/2 bracketed?

Now v is velocity and I have guessed that ^2 means squared.

What is the decimal point between m and v

Dave.

[whitakerb]

gotta love it i have you all arguing about physics hahah

Can we all just agree on one thing?
Pack the shovel next time

Ben

[austastar]

Pack the shovel next time


Ok.

cheers

[slug_burner]

I thought the units of power are Watts??? (1 Watt = 1 Joule/second)

You are correct. It was late, that's my excuse:eek:

[slug_burner]

No I am not pulling your leg.
I do understand all about Kinetic and potential energy.

What I didn't understand and still don't is how to interpret the formula.

Your original post had this,

Kinetic Energy (KE)= (1/2)m.v^2 Units are joules (or kg/sec^2)

Force = m.a Units are Newtons (or kg.m/sec^2)


Ok the (KE) means Kinetic Energy.

(1/2)m I assume means half the mass. Why is the 1/2 bracketed?

Now v is velocity and I have guessed that ^2 means squared.

What is the decimal point between m and v

Dave.

Dave,

The 1/2 was bracketed because I thought it would make it clearer that I was writing a fraction, I could have written 0.5 but it is seldom written as a decimal multiplier. Yes the 1/2 applies to the whole product of mass and velocity squared, so taking 1/2 the mass and multiplying it by the velocity squared will give you the correct result.

a dot in some circles can mean multiplication, I could have left it as 1/2mv^2 or 1/2 x m x v x v but thought that the x would get confused for a variable instead of the multiplier sign.

I should have gone to bed instead of thinking about Newton's Laws of motion.

[d2dave]

When I went to school the equation would be written like this

https://www.aulro.com/afvb/ (http://img190.imageshack.us/i/equationr.jpg/)

When I was in year 8 at school we were sent home to watch man land on the moon on a black and white TV.

So this is why I couldn't understand the modern version, especially the dot between m&v.

Dave.

[Lotz-A-Landies]

When I went to school the equation would be written like this

http://img190.imageshack.us/img190/9969/equationr.jpg (http://img190.imageshack.us/i/equationr.jpg/)

When I was in year 8 at school we were sent home to watch man land on the moon on a black and white TV.

So this is why I couldn't understand the modern version, especially the dot between m&v.

Dave.
Sorry Dave, I can't believe you. The image you've displayed looks like a dry marker on a white-board. If you were going to school when Neil was walking on the moon one day on your B & W TV. Then the equation would have been written on a black-board (which were usually green) in chalk! :p ;)

But I get your drift!

Diana

[d2dave]

Sorry Dave, I can't believe you. The image you've displayed looks like a dry marker on a white-board. If you were going to school when Neil was walking on the moon one day on your B & W TV. Then the equation would have been written on a black-board (which were usually green) in chalk! :p ;)

But I get your drift!

Diana

Black texta on a piece of paper.

Dave.

[DiscoStew]

In my world we use * for multiplication to avoid confusion with x which, as you say, could be mistaken for a variable.

The . notation took me a couple of secs to work out and I assumed was old school.

I am wanting someone to point out in simple terms the flaw with the walking speed with snatch strap to pull someone out argument. The way I read that, if you vehicle was just a bit bogged then you could self recover with a snatch strap and a pair of shoes with good traction :D

[whitakerb]

I am wanting someone to point out in simple terms the flaw with the walking speed with snatch strap to pull someone out argument. The way I read that, if you vehicle was just a bit bogged then you could self recover with a snatch strap and a pair of shoes with good traction :D

Sure could.

If you weighed 2 tonne

The mass is doing the work so you better get down to maccas pronto

Ben

[disco_thrasher]

its a tragic thing to have happened and as has been said before it stresses the use for common sence , rated recovery gear and points , i like to winch rather than snatch unless all that is needed is a gentle pull like a tow , also making sure there is nobody in close proximity to whats going on especially inside the car besides the 2 drivers.. i suppose hindsight is a wonderful thing. but things like this happening are going to quickly destroy whatever privilages we have left as offroad enthusiests im sure many will agree.. Just my 2 cents. Dan.

i agree with you Dan i paid more money for my warn winch than my recovery points and strap ,so why not use it if you got it ???????'shock loads from snatching are unbeleivable

at least i am getting my moneys worth and have control over the situation

[disco_thrasher]

Say for example my Rangie is up to its sills in mud and isn't going to go anywhere easily, suggesting as per US Army manual it will need approx 18T of force to remove from the hole

Snatch strap is attached to my Rangie and recovery vehicle with a 3500kg bow shackles.

If the recovery vehicle moves at walking pace and my maths are correct you will apply the following force on your gear.

For the sake of the argument, my Rangie is an immovable object and we are ignoring any other outside forces.

Mass = Recovery vehicle = 2000kg

Velocity = walking pace = 3km/h = 0.833333m/s

F = X KG

X= M*V

= 2000*0.83333 = 1666.66

Force = 1666.66KG

So not too much, but to overload the bow shackles we only need 3500kg of force;

F = 3500

M = 2000

V = F/M

3500/2000

1.75m/s = 6.3KM/H

So again if my maths are correct, you need to be doing 6.3km/h to overload a 3.5 T Bow shackle, however you are not likely to break it due to its safety factor which is IIRC 500% so 17.5T

Not much IMHO

Now say the Reece hitch was fully welded, and rule of thumb is 1 inch of weld will hold 1000kg then:

Reece hitch is 50x50mm = 8 inches of weld = 8000kg breaking strain, were not looking at a great deal of speed to create a lethal object.

If anything, make sure you pack your shovel next time so you can do the walking pace recoverys rather than trying warp speed to 'pop' it out of the bog

So condolences out to the victims family and hopefully it wakes us all up when on the tracks

very well discribed in the speeds which are required ,i see snaches (LOL) been done where i can not get me and my family out of there quick enough SCARY STUFF:eek:

[LandyAndy]

WHO IN THEIR WISDOM WOULD WELD A TOWBAR RECIEVER TOGETHER,MADNESS!!!!!!
I get the pleasure of recovering lots of our shire equipment,got the same operator twice yesterday on both the rubberguts and vibe rollers:cool::cool::cool::cool:
Had to use the "Golden Chain"(costs a carton of beer to use:cool::cool::cool:) each time,its permanently hung off the rear of my grader.The links are 4 inch each!!!!
I position myself for the best traction,engage the diff lock and 1st gear,slowly take up the slack,and soon as the wieght takes up and its apparent the grader isnt going to pull the machine out alone I lift the rippers wich I had previously set at their lowest point without hitting the ground.(the tow hitch is on the ripper bar)The hydraulics are much more powerful that a wheeled pull,the lift also increases weight on the tyres wich gives the traction.The 13T vibe roller I pulled out of the creek yesterday looked to be lost till summer,but came out relatively easy.
Never use any violent action just slow and sure it always works.
Andrew

[austastar]

Just a link to forces needed for recovery here (https://www.juststraps.com.au/pdf/4x4%20Force%20Calculation%20for%20Recovery2007.pdf )
From the Just straps web site
cheers

[foz.in.oz]

Yep, their slogan is probably the cause of most snatch strap accidents out there........

"Just strap it and GO!"

:mad:

[Mooloolah-Paul]

Back in 1973-75 I regularly took my 86 inch series 1 into the wilds of Cape York (based in Chillagoe if anyone knows it). I was usually alone with no winch. I unbogged her alone at least six times and never had to walk home. I used to take a shovel, two hydraulic jacks and four planks of 2 by 8 inch hardwood. At worst I jacked her up using a plank as a base and put another plank under the wheel. Repeat other side. Low range, first gear, hand throttle and push. Never a problem; it just takes time.

When I pulled my neighbour's heavy overpowered Landcruiser out of the mud I always used a chain around the axles. Again, low low gear and a touch of hand throttle.

Those old timers didn't carry wallaby jacks, shovels and ex-army sand mats for nothing.

I would never use a snatch strap. Too dangerous. :)

[disco2hse]

I know, it's been a while on this thread but...

YouTube- oh ****!!!!!!!

Oh, and it is in Ireland so the truck would be RHD I think.

Alan

[disco2hse]

And while we're talking about it, someone's father obviously got a little too close and personal with their sister.

Check out timecode 5:00 onwards.

YouTube- 4x4 Kiwi Style 2008

Alan

[flagg]

YouTube- 4x4 Kiwi Style 2008 (http://www.youtube.com/watch?v=XV5qjW_xTys)

What a complete idiot. And the nob standing next to them too.

[Debacle]

Could've been the first Darwin Award for 2010

[jplambs]

I know of a bloke that did something similar trying to pull out a tent peg with his Dad's brand new Statesman, put a lovely hole right in the back middle above the towball. :wasntme: (Honest actually, Dad's never owned a statesman)

[rmp]

just one quick point; no towball is rated for 3500kg. It is rated to tow 3500kg, and the force required to move 3500kg on wheels is a lot less than 3500kg -- specifically, around 85kg according my tests on a flat level surface. Add in a whole of other factors such as gradients, braking, accelerating and you still don't come anywhere near 3500kg required to move a 3500kg trailer.

[FifiLámour]

Newbie here trying to make sense of this as we intend to go off road in the next few weeks:

So is the nett of the above to never use a tow bar or tow ball as a recovery point?

If so, what do you do if there's no recovery point available on the front or it's not accessible?

Would you strap your snatch strap around an axle?

[Pedro_The_Swift]

NEVER a towball!!

a square Hayman reese type receiver (Pic someone?)can be used if required,

and always, slowly slowly is the go,,

[rmp]

Newbie here trying to make sense of this as we intend to go off road in the next few weeks:

So is the nett of the above to never use a tow bar or tow ball as a recovery point?

If so, what do you do if there's no recovery point available on the front or it's not accessible?

Would you strap your snatch strap around an axle?

Best thing to do is go to a training course or ask one of your club trainers -- it's much easier to show than to explain on a forum. But the towball and towbar are quite different. Recovering using a towball is wrong. Recovering using a towbar, for example inserting a strap and putting the hitch pin through the strap is ok.

You have a D3 which has recovery hooks front and rear, use those plus shackles.

If there is no recovery point available then you have to improvise, and many times vehicles can be self-recovered after some digging, jacking and driving, or by use of recovery ramps. If you do need to tow then winch as there's less stress, spread the load as evenly and far as you can. Snatching out should not be seen as an automatic first-choice recovery method, and ALWAYS check the vehicle is not irretrievably hung up before you tow.

If in any doubt just leave it and live.

[Sparksdisco]

Arnt we missing a little of the point.


WHO WELDS A TOWBAR TOGETHER!!!

[dullbird]

Arnt we missing a little of the point.


WHO WELDS A TOWBAR TOGETHER!!!



well I would assume most manufacturers. how else would they be put together

[Sparksdisco]

A bit of info to clear up the guessing in relation to what occurred in the accident.


The tounge and square section that slides into the Hayman style receiver had been welded in the past. During the snatch the weld broke sending the tounge, ball and strap through the windscreen narrowly missing the driver, into the rear section where the lad was in the third row seat.
Andy

well I would assume most manufacturers. how else would they be put together

Well derr :p

I dont think it was the manufacturers welds

[dullbird]

well I would assume most manufacturers. how else would they be put together

Well derr :p

I dont think it was the manufacturers welds

there are many many people out there quite capable of welding a tow bar I can assure you:).....

yes maybe his failed due to poor welding I don't know, but to say who on earth would weld a tow bar. Who on earth would weld a chassi or a roll cage all of which can be put under hugh strain and cause damage if let go

[austastar]

Hi, did a search on the Justice Dept's website for the lad's name and location, but the Coroner's report is not yet listed, if indeed it has been heard to date.
Should be some expert witness statements available when it is published.
cheers

[Sparksdisco]

there are many many people out there quite capable of welding a tow bar I can assure you:).....

yes maybe his failed due to poor welding I don't know, but to say who on earth would weld a tow bar. Who on earth would weld a chassi or a roll cage all of which can be put under hugh strain and cause damage if let go

Shure if you are qualified to weld to a australian standard and know what you are doing And can certify the welding meets standards then by all means.

But if any one who new what the where doing would of proberly just brought a new one as they are cheep to buy anyway.

I dont condone the use of towballs to recover but like a lot of people said they still use the toung with a rated shackle in it and think it,s safe. even if he did this it still would of ended up killing him.

Still a lot of iffs and buts and assumptions.

[bblaze]

I believe that the towbar was a hayman reese type, the square section had been welded in and no locating pin was inserted, most of the weld had broken over time and only a small section of weld failed to cause the accident. This is all here say in the local community but it has come from a realiable source.
blaze

[disco2hse]

Arnt we missing a little of the point.


WHO WELDS A TOWBAR TOGETHER!!!


Never seen a towbar that was not welded together.

[disco2hse]

What a complete idiot. And the nob standing next to them too.

Ayup, kind of the point really. Just lucky no one was in that passenger seat.

And in the previous vid from Ireland, they were using chain and nothing to absorb shock.

Alan

[Ranga]

Boy killed in towing accident - ABC News (Australian Broadcasting Corporation) (http://www.abc.net.au/news/stories/2010/12/12/3091225.htm)

[CraigE]

Oh dear, that is real sad just before Chrissy or at any time really.
Another case of towing incorrectly.

[weeds]

i heard on the radio this morning......sad indeed

[RichardK]

very sad, he was somebody's son.

[VladTepes]

Bloody sad alright.
Another situation of a tie down point being used as a tow point ?
They ought to remove the damn things from cars when they drive them off the trucks at the dealers....

[JDNSW]

Bloody sad alright.
Another situation of a tie down point being used as a tow point ?
They ought to remove the damn things from cars when they drive them off the trucks at the dealers....

But then how will the tow truck operator tie it down when returning it to the dealer for warranty repairs?

Two points about the accident -

1. He should not have been anywhere where he could get hit if anything failed
2. It will be interesting to find out what actually failed. Could have been the hook, for example.

I hope nobody from here was involved, but it serves as a reminder that recovery or towing is potentially dangerous and needs to be treated as such.

John

[101RRS]

My reading between the lines is that they were 2wd cars that had been bogged - afterall if it had been 4wds the media would not have passed up the chance to mention this.

Its sounds like it was a 2wd tow hook that came off rather than a tie down point but information is sketchy in the report. In either case both are not up to it for deeply bogged cars.

Garry

[Lotz-A-Landies]

A very sad situation close to Christmas! :(

Yes it did say "hook" in the article and as we know, rated "D" shackles are the way to go.

How many "tow ropes" do you see in auto parts stores with bent round bar hooks at the ends?

[LSD_AUTOMOTIVE]

Awful :( The poor family

[korg20000bc]

Horrible situation for the families involved.

Now, get ready for the nanny state knee-jerk reaction.

[austastar]

Hi,
The Coroner's report on this is now on the web. Link (http://www.magistratescourt.tas.gov.au/decisions/coronial_findings/s/stein,_joshua_phillip_-_2010_tascd_418)

A tragic death, and avoidable, had an appreciation of the forces involved in recovery and general principals been observed.

Regards

[101RRS]

I take it that a "genuine Toyota" tow bar is in fact a HR bar and that it was rusted inside the tube and that the removable section was poorly made.

How many of us check inside the square tube on our bars for corrosion etc and if we have to replace the tongue how often do we check it all out and just accept it is built right.

While they did have the snatch strap on the tow ball, this accident would have still happened if a proper recovery hitch had been used in the tow bar receiver.

This also highlights the need to use dampers - not necessarily one in the centre but at the ends as well.

Garry

[that_kid]

The flying towball often gets mentioned with snatch strap incident. The really dangerous bit of equipment is the snatch strap.

Too ealy to say but the article from Tasmania talks about the towing assembly and other bits as well as the ball. The one common item here is the snatch strap. Snatch straps need a big warning and perhaps buyers should be licenced to use them.

The towball is rated to 3500 kg as a max towing weight. Including a suitable safety factor on top of the acceleration/deceleration force when the trailer pushes against the towball (reduced with braked trailers) and the ball should be able to handle significantly more. Have a look on the front of 4wds that have lifting eyes on the bullbar. What are they rated to? Are you any better off using them to recover with?


Ill secound that i have seen an ARB bar come off a vehicle bein snatched so realisticly as you said its the snatch strap that is the risk. I can only speculate at the actual load that is put on the recovery point during a snatch recovery and obviously this will change from a sand recovery to a mud recovery.

Everyones usually out of the cars when we do recoveries for a number of reasons,

More hands to help,
Less weight in the vehicles,
And of course so you can hassle the driver of the sunk vehicle.

I feel sorry for the bloke in the front seat who saw the 'tow assembly' come through the windshield n catch his mate in the face...

[miky]

I am trying to understand that the towing assembly landed 90m behind the vehicle after travelling through the vehicle.
NINETY METRES!!!

From the report:
"...The vehicle rolled and suffered significant damage"
"...the vehicle had sunk into the mud up to its axle and was firmly bogged"

And they still drove it - before it got bogged.

As has been said, highly unlikely that a snatch strap was going to work.
The forces must have been tremendous.
With a "proper" recovery point I assume that the strap would have broken with no steel flying around.

Tragic end.

.

[austastar]

it was rusted inside the tube and that the removable section was poorly made.

Hi,
that is my reading of it i.e.

8<--------------------
The tongue plate has been joined to the RHS hitch by an external fillet weld around all four sides. It was evident water had accumulated at the closed end and caused corrosion. The extent of corrosion was consistent with what would be expected from sea water. Wall thickness had been reduced by corrosion from 4mm to 2.mm along the top of the RHS, 2mm along the sides and 1 mm along the bottom. Average loss of wall thickness would have been greater than 50 percent.
8<-----------------------

It would seem that the goose neck with tow ball (toungue plate) was peeled off the hitch insert and travelled through the recovery vehicle, to be eventually found 90m away.

Now I'm no engineer or physicist, but I imagine that the force required to do that would be impressive.

regards

[Hymie]

Hi,
that is my reading of it i.e.

8<--------------------
The tongue plate has been joined to the RHS hitch by an external fillet weld around all four sides. It was evident water had accumulated at the closed end and caused corrosion. The extent of corrosion was consistent with what would be expected from sea water. Wall thickness had been reduced by corrosion from 4mm to 2.mm along the top of the RHS, 2mm along the sides and 1 mm along the bottom. Average loss of wall thickness would have been greater than 50 percent.
8<-----------------------

It would seem that the goose neck with tow ball (toungue plate) was peeled off the hitch insert and travelled through the recovery vehicle, to be eventually found 90m away.

Now I'm no engineer or physicist, but I imagine that the force required to do that would be impressive.

regards

Yeah, and having a poxy little recovery drag chute thing would have slowed it down enough to save them..... NOT!!!!

[CraigE]

Yeah, and having a poxy little recovery drag chute thing would have slowed it down enough to save them..... NOT!!!!
The point of a damper blanket is that it will dflect some of the energy downward and displace a large % of the remaining energy by hitting or dragging on the ground.
A damper will not have a lot of effect on a projectile and this comes back to incorrect application (use of towballs, hooks without pins etc).
A damper is generally used to stop the strap, chain or cable recoiling.

[Hoges]

Sadly yet another death ...this time near Hervey Bay yesterday...the poor kid was only 14 yrs old.

Boy killed in towing accident - ABC News (Australian Broadcasting Corporation) (http://www.abc.net.au/news/stories/2010/12/12/3091225.htm)

[George130]

First snatch I did ws on an AULRO trip. Classic Rangie deliberatly stuck in a hole so I could try the gentle pull.
I tend to have the winch out before others can get near me so I know how it will be done.

[RichardK]

As I read it the report mentioned a "towing Hook".

Now I don't know the details, obviously, but here are a few thoughts:

Sale of snatch straps

A snatch strap is a very lethal weapon, lethal weapons are generally controlled or licensed.........
Perhaps for every snatch strap sold there should be an explicit set of instructions to be read prior to purchase and signed off by the purchaser?
Perhaps for every snatch strap sold there should be a mandatory lesson in the usage of such
Perhaps a certificate of compliance with those or similar conditions to be held by the user of a snatch strap would be sufficient within a group to provide confidence in the person in charge of a recovery.
Perhaps every snatch strap is tagged with a message "DANGER Only to be used with certified recovery points"

Tow Balls

Perhaps every 4WD towbar is etched with the message " DANGER Under no circumstances is a towball to be used as an anchor point for recovery" or a similar message


Front Bars

I am not sure but I would suspect that there are some ADR's for the front bars, if so then those that do not meet certain criteria as determined by design engineers(?) should be plated with "DANGER this bar is not designed for recovery of your vehicle"

Just some thoughts as I feel there are certainly some people who need to be protected from themselves, although any measures would not stop some people from deciding that they don't need to be told

[Tikirocker]

As I read it the report mentioned a "towing Hook".

Now I don't know the details, obviously, but here are a few thoughts:

Sale of snatch straps

A snatch strap is a very lethal weapon, lethal weapons are generally controlled or licensed.........
Perhaps for every snatch strap sold there should be an explicit set of instructions to be read prior to purchase and signed off by the purchaser?
Perhaps for every snatch strap sold there should be a mandatory lesson in the usage of such
Perhaps a certificate of compliance with those or similar conditions to be held by the user of a snatch strap would be sufficient within a group to provide confidence in the person in charge of a recovery.
Perhaps every snatch strap is tagged with a message "DANGER Only to be used with certified recovery points"

Tow Balls

Perhaps every 4WD towbar is etched with the message " DANGER Under no circumstances is a towball to be used as an anchor point for recovery" or a similar message


Front Bars

I am not sure but I would suspect that there are some ADR's for the front bars, if so then those that do not meet certain criteria as determined by design engineers(?) should be plated with "DANGER this bar is not designed for recovery of your vehicle"

Just some thoughts as I feel there are certainly some people who need to be protected from themselves, although any measures would not stop some people from deciding that they don't need to be told



Give bureaucracy an inch and they take a mile ... common sense is all that is required. Not everybody has it and you can't ever legislate the stupid out of people. The last thing we need are more laws, more permits, more government in our business. :mad:

Simon.

[JDNSW]

I agree with Simon. It is impossible to make life entirely safe, and the number of this sort of accident is not sufficient to even start to justify this sort of bureaucracy. As an example of similar bureaucracy, has anyone ever done any sort of cost/benefit analysis on the requirement for certification of towbars, introduced about fifteen years ago? Certainly in fifty years of driving I have never known of an accident related to a towbar failure, although I am sure they have happened. But not very often.

Personally, I regard snatch straps as far more dangerous than firearms! (But then so are cars)

John

[Hymie]

The point of a damper blanket is that it will dflect some of the energy downward and displace a large % of the remaining energy by hitting or dragging on the ground.
A damper will not have a lot of effect on a projectile and this comes back to incorrect application (use of towballs, hooks without pins etc).
A damper is generally used to stop the strap, chain or cable recoiling.

And you have a 50% chance of the damper being on the right side of a break too. The safest way to use Recovery gear under load is to stand 1 to 1 1/2 times distance of the length of Snatch strap or winch rope you have laid out.
It just Pees me off to no end watching those videos you get with magazines showing some peanut walking alongside the winch rope and moving the damper so it doesn't foul on stuff. Leave it off and get the hell out of there!
Recovery Dampers are a FAD that will get someone killed before long.
There, I've said it. I hope and pray I'm wrong but I know in my heart that I'm right.

[disco2hse]

Mainly as a result of this thread, similar discussions here and elsewhere, and careful observation of plonkers, I rarely get the snatch strap out anymore and only if I can be assured that recovery will be safely accomplished (never if the vehicle being freed is bogged in mud). Instead I will use the winch or even a hand winch. Slow and careful permits time to stop, think, release, and adjust as required.

Alan

[Redback]

A picture tells a thousand words
https://www.aulro.com/afvb/

I have a feeling it may have helped, would have slowed it's momentum at the least.

Baz.

[Tank]

Not all tow balls are rated, and of those that are, not all are rated for 3500kg. A lot of the cheaper tow balls don't have a rating, along with a lot of the older ones. The majority of 4wds have a hitch receiver type towbar, remove the hitch, put the strap through the receiver and use the pin to locate it. I have seen bent pins before, but never heard of one snapping. If it did happen to snap both sides of the pin would still be stuck in the receiver and only the strap would fly out. A strap on its own is not particularly lethal, but attach a solid object to the end of it and it's a whole different ball game. If I had a towbar that wasn't a receiver type, I personally would be removing the towball and then inserting a rated shackle through the hole to attach to. Even a 3.2T rated shackle will not self destruct until more than 16T of force has been applied to it.
What you say about tow balls is true, but the main problem is 1. snatch strap recoveries and 2 lack of knowledge and commonsense.
First up education is needed but most don't wan't to be told what to do and commonsense is very thin on the ground.
Secondly IMHO Snatch Straps and Snatching (out of a bog) should not be allowed, banned, legislated against.
I have been a Class 1 Ticketed Rigger for 40 years and NOWHERE in the rigging industry, mining/construction area are any products, such as slings, straps, chains, rope block and tackle or lifting gear that have an ELASTIC property built in. Nylon ropes in block and tackle is banned, because before they were banned people were killing thereselves, because of the elasticity inherent.
One Poster says that there didn't seem to be these sorts of accidents years back, but back then snatch straps were hardly known or used.
Think about the energy thats released during a snatch recovery, now if you haven't been able to debog using a winch/tow strap or chain, a snatch strap is connected and the bogged vehicle is pulled out, if you couldn't move it with conventional means using ever so many tonnes of pressure, then can you imagine how much "tonnage" was stored in the snatch strap under full load.
I don't think any available tow point is safe enough to use with a snatch strap, as I would bet my left nut that NOBODY has ever measured the energy involved and how would you measure it. I doubt that it would be possible to setup a scenario that would give an average Working Load of a snatch strap actually working, there are too many variable, i.e. steepness, type of material bogged in sand/mud etc.
I have had a snatch strap for around 5 years now and it is still in its original wrapper (a present), because of my rigging experience I am wary of it, but all that said they do have a role to play, but the big 'IF" is only if they are used moderately and with some knowledge and a whole lot of commonsense.
It is getting to the point where the number of deaths involving snatch strap recoveries is going to get some Politician who want's to get his name in the media to jump on the Ban Snatch Straps wagon, the thin edge of the wedge, Regards Frank.

[Tank]

As per usual I wrote the above post without looking at the original posters date, but still relevant none the less.
Noted that one poster said along the lines that the driver of the snatch vehicle may have seen the tow/bar/ball coming. Well I doubt that, if you watch some of these disastrous snatch recoveries on U-tube you notice the loud crack when the strap breaks, well that loud crack is the end of the snatch strap and attachments breaking the sound barrier (750mph) as it flies past your head and in this case landing 90METRES behind the vehicle after travelling through 2 windows and a young lads head. Someone said more dangerous than a gun, more likely more dangerous than an artillery piece.
Anyone care to try and work out how much energy was involved here, Regards Frank.

[VladTepes]

The problem with starting to label "non compliant" ones is taht people will then make the assumption that unless they are labeled as "non compliant" they are therefore compliant ! Dangerous in itself.


Give bureaucracy an inch and they take a mile ... common sense is all that is required. Not everybody has it and you can't ever legislate the stupid out of people. The last thing we need are more laws, more permits, more government in our business. :mad:

Simon.

Amen brother !

[KarlB]

Details are starting to emerge about this tragic and unnecessary death: Tow Rope That Killed Teenager Addison Yates Went 'Like Slingshot' (http://www.brisbanetimes.com.au/queensland/broken-tow-rope-like-slingshot-killing-boy-in-back-seat-20101214-18wa0.html)

Cheers
KarlB
:(

[isuzurover]

Details are starting to emerge about this tragic and unnecessary death: Tow Rope That Killed Teenager Addison Yates Went 'Like Slingshot' (http://www.brisbanetimes.com.au/queensland/broken-tow-rope-like-slingshot-killing-boy-in-back-seat-20101214-18wa0.html)

Cheers
KarlB
:(


It seems the two bolts holding the tow hook sheared. I would bet they were bunnings specials and not class 8.8 or higher as they should have been...



Broken tow rope 'like slingshot', killing boy in back seat
Marissa Calligeros
December 14, 2010 - 1:24PM

Addison Yates.

Addison Yates.

Addison Yates was sitting in the back seat of a four-wheel-drive bogged in bushland mud when the hook of the tow rope being used to pull them free came loose, catapulting through the rear window like a slingshot at a speed of up to 160kmh.

The hook hit the 14-year-old boy in the head, killing him.

Details emerged today of the tragedy, which occurred outside Hervey Bay on Sunday evening.
Advertisement: Story continues below
Addison Yates. <B><A href= Freak towing strap death devastates family (http://www.brisbanetimes.com.au/queensland/freak-towing-strap-death-devastates-family-20101214-18vs9.html) > Fraser Coast Chronicle </a></b>

Addison Yates. Fraser Coast Chronicle

Addison had been 'bush bashing' with two mates when they became bogged on a sodden dirt track in the Vernon Conservation Park, in Walligan.

Four friends in two other 4WDs tried to haul the vehicle out of the mud.

Addison's friends, believed to be aged between 17 and 21, connected the three 4WDs together in a convoy with snatch straps.

The region had been soaked with rain earlier in the day, but the rain continued to fall as the group tried to reverse the bogged vehicle out of the mud on Dundowran Road.

Addison sat in the back seat, facing backwards to watch the action.

But the group had underestimated the tension two vehicles would place on the towing straps.

Detective Sergeant Bruce Hodgins said the force was so great on one strap the metal hook was sheared off the tow bar and catapulted back towards Addison.

"It acted like a slingshot," Sergeant Hodgins said.

"The two vehicles put an unbelievable pressure on the strap. There was also incredible pressure on the middle vehicle.

"The hook bolts couldn't take the pressure."

The tow strap used was designed to bear a load of five tonnes, but the two vehicles created a load of about seven tonnes, Sergeant Hodgins estimated.

He said Addison and his friends often went bush bashing and were not unfamiliar with the terrain in the reserve.

"Did his friends act irresponsibly? No," the police office said.

"Did they underestimate the force of the two vehicles? Yes."

Queensland University of Technology physicists Stephen Hughes and John Barry estimated the hook would have catapulted through the rear windscreen of the 4WD at between 100 and 160kmh.

However Dr Hughes, a medical physicist, said the force would not need to be great to cause fatal head injuries.

"Even the slightest bump on the head can be fatal," he said.

"The person in this case would have suffered severe brain damage if they had not died."

Emergency crews waded through chest-deep water in a flooded creek to reach the group after searching for them for hours.

"It took some time for police and ambulance crews to get to him," Sergeant Hodgins said.

"[Addison's friends] offered what assistance they could, but they realised there was little hope."

Addison was the son of Hervey Bay Pastor Darryn Yates, who operates the Church by the Bay and a drug and alcohol rehabilitation centre. A widower, Pastor Yates runs the centre with his new wife, Jill, after Addison's mother Dianne died.

Friends and family expressed their grief and disbelief on social networking site Facebook yesterday.

"He was such a kind and giving person. Why did he have to die?" one friend wrote.

Anther said: "He was the nicest kid. Man you are goin' (sic) to be missed so much."

Sergeant Hodgins said the tragedy served as a warning to others planning to go four-wheel-driving in the holiday season.

"This could have happened to anyone, anywhere," he said.

"It could have been a mother, or a very young child sitting in that seat."

He recommended training courses in towing bogged vehicles to help prevent future accidents.

[THE BOOGER]

Still hard to work out as in this story they interchange tow rope and snatch strap as if they were the same. But three 4wd in a row will easily apply more than 5 tonne of force especialy if there is monemtum in the towing vehicals. Irresponsible maybe definatly untrained and not equiped correctly should have been a winch or chains before tow or snatch straps very sad definatly:(

[87County]

sadly... from the newpaper report


"He said Addison and his friends often went bush bashing and were not unfamiliar with the terrain in the reserve.

"Did his friends act irresponsibly? No," the police office said.

"Did they underestimate the force of the two vehicles? Yes."

Queensland University of Technology physicists Stephen Hughes and John Barry estimated the hook would have catapulted through the rear windscreen of the 4WD at between 100 and 160kmh."




..................education is obviously necessary

[101RRS]

All the reports I have read all talk about "tow hook" and "snatch or tow' rope.

So did they use a winch cable style hook on a snatch strap to attach to the car - winch hooks would be only rated to half what is required in a snatch.

Or - maybe they had a mix of snatch straps and a "tow" rope - the ones with the open wire hook on the end and of course this would not be up to scratch.

I suppose clear details will not come out for some time as they finally have in the sad Tas incident.

Garry

[Hymie]

A picture tells a thousand words
http://www.arb.com.au/media/products/recovery/Hero_damper.JPG

I have a feeling it may have helped, would have slowed it's momentum at the least.

Baz.


No No No No No No and a thousand times more NO!
Assuming the hook that came off weighed .5 of a Kilogram, at 180 KmPh it would have had around 1.8 Tonnes of kinetic energy.
How much drag would that poxy damper give?

[101RRS]

No No No No No No and a thousand times more NO!
Assuming the hook that came off weighed .5 of a Kilogram, at 180 KmPh it would have had around 1.8 Tonnes of kinetic energy.
How much drag would that poxy damper give?

A lot - once the kinetic energy has been expended (when the snatch strap has returned to its normal length) the weight of the (friction on the ground) and air resistance of the "winch blanket" would come into play and certainly slow the projectile down - maybe not enough to prevent damage or injury but maybe enough.

Garry

[Hymie]

A lot - once the kinetic energy has been expended (when the snatch strap has returned to its normal length) the weight of the (friction on the ground) and air resistance of the "winch blanket" would come into play and certainly slow the projectile down - maybe not enough to prevent damage or injury but maybe enough.

Garry


Yeah, but by the time it's broken free it's still going to travel on it's original trajectory and reach the target car around the same time the damper takes effect. Think about it.

[101RRS]

Yeah, but by the time it's broken free it's still going to travel on it's original trajectory and reach the target car around the same time the damper takes effect. Think about it.

Your correct if the damper is in the middle - I use two, one at either end.

Garry

[Hymie]

Your correct if the damper is in the middle - I use two, one at either end.

Garry


Hymie draws X on wall and drives head into it repeatedly........

[miky]

I reckon you two guys should just go out and try the two methods - with and without the damper.

Post the results here.
:D:D:D:D:D