Recovery and Towing

[Stormin]

Older leaf sprung Land Rovers don't have facility for Jate rings so the best alternative is the bumper D rings shown.

 

[ATTACH=CONFIG]35766[/ATTACH]

 

These are attached again with M12 Gr 8.8 bolts, four for each eye two long ones which pass right through the D ring base plate, bumper and front dumb irons, and two short ones which pass through ring base and top surface of front bumper only.

The only good point on on the rear is the tow hitch unless you want to risk using the spring shackles. On most Military Land Rovers you've got the nice heavy duty Nato hitch fastened directly to the rear crossmember with four M12 High tensile bolts and a backing plate behind the crossmember so the bolts don't pull through. Beware of any drop plates fitted as these will likely bend under strain of recovery and twist the crossmember also.

[recymech66]

I think some clarification is required on the difference between the Jate Ring and the lashing / tie down eye, which both affix to the same points on the chassis.

 

Jate ring [ATTACH=CONFIG]35764[/ATTACH]

 

Lashing eye [ATTACH=CONFIG]35765[/ATTACH]

 

The Jate rings should be used in a pair and fixed to the chassis using M12 Grade 8.8(min) bolts.

 

Jate rings on military Land Rovers can be used for lashing/winching and suspend tow and your correct, should always be used as a pair to evenly distribute the load. Your bottom photo shows a civilian pattern towing/lashing eye not fitted to any inservice military vehicle. Obviously these are fitted to civilian Land Rover Discovery/Defender and are NOT recommended for winching/recovery

[Tony B]

o you know where Jate rings may be obtained?

[recymech66]

o you know where Jate rings may be obtained?

 

You can buy them from most online Land Rover parts dealers or 4x4 specialist retailers online or otherwise I think they cost around 15 quid each.

 

http://www.rebel4x4.co.uk/steering_guards.htm

 

http://www.famousfour.co.uk/foursport/shackle.php

[Tony B]

Thanks

[cosrec]

[ATTACH=CONFIG]35848[/ATTACH]

 

Above is similar although not identical to what we use for recovery on all vehicles under 3.5 tons wether for pulling up slide bed or winching out. We place out board of spring mounts on conventional axles and as near to suspension/body mounts on all other vehicles.

[antarmike]

I have a number if 1" BSF eye bolts eyes as fitted to Ergo cabs AEC/ Leylands etc, Routeman Trunkers and various buses. Anyone into Rally field recovery may come across a stuck bus, You need these in your tool BOX!!!

 

Grab a pair while you can get em see classifieds....

[cosrec]

Have read comments on MoD vehicles re recovery pionts. So its a case of using what you trust. The bulk of vehicles we attend are not fitted with any recovery pionts. As i mentioned in another post i have no problems using manufacturer fitted trailer hitch pionts but in the absense of these we advise all our drivers to hang on to axles on bogged upright winching. We dont even use tow bar hitches on cars anymore except for mild pulls having had these rip out of bootfloor when pulling out of dykes etc. Like Recymech66 pionted out there are differences between Mod and civillian ways of doing things but it is worth bearing in mind if your friend asks if you for a pull out of some mud say with his private car dont be tempted to use those flimsy lashing pionts or that stupid screw in eye that comes with them. You will probably be lucky and get away with it or it could cost you some apologies and money.

By the way if you decide to go along the route of using the J hook bridal i posted earlier they are always fitted upside down eg hung on from underneath.

[cosrec]

Standard on Military Land Rovers mate, older MV's like Bedfords etc it's always best to form an apex using strops or chains reeved around the spring hangers, very strong. Quite a few vehicles have recovery eyes (Defence Standard) which are connected/welded to the chassis, these are obvious recovery attachment points and are extremely strong.

 

We are never taught to go around axles as most MV's have driven front axles and the casings (which the half shafts go through) could easily deform, and cause irrepairable damage. Army recovery mechanics employ some different techniques to civilian recovery operators due to the nature of the vehicles, however most recovery techniques can be used for both civilian and military. We could learn a lot about roadside recovery from the civilian operators, especially side over sides, or rollovers in civi speak..

As you quite rightly state recovery techniques vary between army and civilian life i think this is more to do with eqipment used then any thing else. Army eqipment is designed for straight forward lifting or straight winching out the back for the most part. Civilian eqipment is designed on a much more budget design but can do elevated winching with a twin winch system. But in general all recovery jobs are the same the whole world over. A successful out come will usually end with some compromise somewhere and be dependant on the knowledge of the operator. Will try and put some posts on for side over sides

[recymech66]

As you quite rightly state recovery techniques vary between army and civilian life i think this is more to do with eqipment used then any thing else. Army eqipment is designed for straight forward lifting or straight winching out the back for the most part. Civilian eqipment is designed on a much more budget design but can do elevated winching with a twin winch system. But in general all recovery jobs are the same the whole world over. A successful out come will usually end with some compromise somewhere and be dependant on the knowledge of the operator. Will try and put some posts on for side over sides

 

Cheers Cosrec,

 

Side over side techniques are probably still very similar but you obviously have to contend with lack of space i.e on motorways etc were as Miliary side over sides tend to happen on exercise areas, open spaces, desert etc, were we can get 90 deg side on with winch and crane or 2 recovery vehicles with 1 to provide a check tackle as it comes over.

[cosrec]

In order to recover an overturned vehicle a bit of theory is required. You can go about it with the yank it over approach and get away with it’ but if its your pride and joy you not going be over happy if crashes to the deck and its got more damage then when it fell over.

I think it is important to understand why it fell over. May seem a bit basic but if you know why it fell over it is the same as a lot of things in recovery you can work it back the other way and use it to advantage.

So why did it fall over you could say going to fast or terrain or wind or maybe impact damage but basically it’s down to CG.

CG stands for Centre of Gravity.

In normal circumstance the CG is pulling a motor vehicle stood on level ground straight down with a force equal to the vehicles weight. The vehicle is stabilizing this force by spreading it through its wheels or tracks. All the time the CG is acting between outer edges of the wheels or tracks the vehicle will stand upright

If the CG is acting straight down through outside of one side wheels or tracks the vehicle is on the point of balance

If it’s laid flat on its side the vehicle is being pinned to the floor with a force equal to vehicles gross wt straight down through CG

Great so we know the CG is giving us problems but where is it.

To try and show more clearly I have put a simple picture on of a vehicle that looks very much like a brick stood on its thin side viewed from one end. This vehicle (brick) is of uniform construction and density through its length height and width therefore its CG will be at the centre of the vehicle (brick) from which what ever way it’s looked at. Sorry if this sounds boring bear with me next post will be more interesting

 

[ATTACH=CONFIG]36292[/ATTACH]

[antarmike]

RAEME website, some interesting stuff here.

http://www.raeme.info/index.php

http://www.raeme.info/toc.php?cat=rec&item=1&page=p7#article

 

welding back Towing eye to facilitate recovery!

http://www.raeme.info/toc.php?cat=rec&item=1&page=p9#article

[cosrec]

Ok vehicle design has moved on a bit from our last vehicle (brick). This one is a 6*6 flat carrying a 20ft container vehicle with a weight of 10tons. It has conventional road springs on it. For what ever reason it has fallen over on a flat road.

The first that springs to mind it to winch it over but we need know to if we have enough winch capacity. If we liken it to a simple bell crank lever the calculation is simple.

First we need a fulcrum this is the outside edge of the tyre where it hits the floor and pivots

Next we need to know where the CG is. One thing for certain it will be as near as dam it to the centre line of the vehicle when viewed from back or front in an upright position.

Its unladen so all the heavy bits e.g. axles engine chassis are near the bottom with lightweight bits high up. There is no exact way in recovery to say its here or there so a good guess is going to be the best we can do.

A general rule of thumb that has worked for me is a little bit above the height of the tyres. This has proved good for cars and all unladen flat bodied and lightly built box vans. On this vehicle I would guess the CG is around the 5ft mark

So we CG (10) times distance from CG to Fulcrum (5) divided by distance from Fulcrum to where we hang the winch (I have chosen mid way up vehicle for this example) (4)

So in theory a fraction over 10x5/4= 12.5 tonnes will see the vehicle stand up. In practice it won’t will explain in later post.

 

 

[ATTACH=CONFIG]36521[/ATTACH]

 

 

So why wont the vehicle stand up. There are two reasons. The first and I have deliberately stressed this.

Because a vehicle falling over on a level road don’t actually end up with its wheels touching floor. Or at least will have no weight on them

So pull as much as you want it will only sledge towards the winch force when rigged as per example. Until you get the wheels to touch the floor with weight on then bite you will do no good

 

Edited October 22, 2010 by cosrec

[cosrec]

So pull as much as you want it will only sledge towards the winch force when rigged as per example. Until you get the wheels to touch the floor with weight on then bite you will do no good

What can be done to alter this? The first thing I would do is move the height I was winching from a good point would be out board of the front spring. This point will mean the winch rope from your vehicle will be going uphill. This has the effect of pulling and twisting the axle downwards on to the floor and causing it to bite in. It also has another good effect if you do the sums again the amount you have to winch has come down.

E.g. originally it was 12.5 ton now its 10x5/6.5= approx 7.7 tons a big difference just for moving winch rope. Every thing you can do to reduce strain on rigging is good and becomes even more so as you move on to heavier vehicles and can make all the difference between success of failure.

Ok checked all rigging again and have another go.

Vehicle cab comes up a little way chassis twists a bit then bang the whole lot crashes back to floor and your back to where you started.

What’s gone wrong? Its back to CG again for sure we guessed where it was looking from the front but ignored looking from the underneath. Again it’s a question of guessing where the CG is. On this next drawing I have made a guess where I think it is taking into account heavy bits engine box etc at front balanced by empty light container at back. Its clearer now the last attempt was a no boner from the start as hung only to front axle it was going to swivel around the point were CG was pinning it to floor. The ideal place to hang to would be straight in line with the CG. Alas the only place you can hang to anywhere around here is the chassis rail but it’s cluttered with fuel tanks or air tanks. The recovery truck only has one winch so the only option is to use some sort of bridal to attach equidistance from the CG in this example I think front axle and second axle would do the trick. As a little bonus this means the load taken by the axles is only half of 7.7 tons so after a few attempts try again and up she comes

 

[ATTACH=CONFIG]36568[/ATTACH]

[R Cubed]

I think some clarification is required on the difference between the Jate Ring and the lashing / tie down eye, which both affix to the same points on the chassis.

 

Jate ring [ATTACH=CONFIG]35764[/ATTACH]

 

Lashing eye [ATTACH=CONFIG]35765[/ATTACH]

 

The Jate rings should be used in a pair and fixed to the chassis using M12 Grade 8.8(min) bolts.

 

How could you get an M12 bolt through that small tube welded to the bottom of the chassis rail, my Range Rovers I have had, I am sure you could only just get an M8 through which is what is used to hold the lashing eye on, I might be wrong, is there a weld on mod to be able to fit those Jate rings ?

[Marmite!!]

Just posted a few guides by the Department for Transport.

 

MAXIMUM NUMBER OF TRAILERS: a brief guide

http://hmvf.co.uk/forumvb/showthread.php?21312-MAXIMUM-NUMBER-OF-TRAILERS-a-brief-guide

 

Note on A-Frames and Dollies

http://hmvf.co.uk/forumvb/showthread.php?21311-Note-on-A-Frames-and-Dollies

 

OVERHANGING LOADS a brief guide

http://hmvf.co.uk/forumvb/showthread.php?21313-OVERHANGING-LOADS-a-brief-guide

 

Safety of Loads on Vehicles

http://hmvf.co.uk/forumvb/showthread.php?21314-Safety-of-Loads-on-Vehicles

Road Vehicles (Authorisation of Special Types) (General) Order 2003

http://hmvf.co.uk/forumvb/showthread.php?21315-Road-Vehicles-(Authorisation-of-Special-Types)-(General)-Order-2003

 

Take note of the DfT's disclaimer:

However, while this is our understanding of the meaning of the Regulations, it is only the Courts which can reach a definitive interpretation of the law.

 

Edited October 25, 2010 by Marmite!!

[ruxy]

I think some clarification is required on the difference between the Jate Ring and the lashing / tie down eye, which both affix to the same points on the chassis.

 

Jate ring [ATTACH=CONFIG]35764[/ATTACH]

 

Lashing eye [ATTACH=CONFIG]35765[/ATTACH]

 

The Jate rings should be used in a pair and fixed to the chassis using M12 Grade 8.8(min) bolts.

 

================================

 

The Land Rover part number for this bolt BH110281L , I think if you investigate further you will find it is only 10mm dia. and not 12mm dia. ..... Not very good on 8.8gr in double shear.

[cosrec]

In haste trying to get boring bits out of way i forgot one very import thing. First thing to check on any roll over is are the brakes on. If the vehicle moves as it comes over the sidewalls of the tyres lose grip and it will crash back to the floor again. In extreme circumstances it can move that far it will tip the recovery vehicle over. Very good vidieo on Utube showing this happening.

Another little fact dont rely on transmission brake to hold vehicle they dont hold anything when set of wheels are off the floor If need be some good timbers back and front of tyres will do the job. Even on level ground you can be inadvertantly be making the vehicle tend to roll back or forth by not being exactly lined up with CG

During the initial part of the recovery it takes very little to dislodge grip on tyres. And i have had an occasion when the draught suction from a passing fridge lorry dropped one back down.

[recymech66]

In haste trying to get boring bits out of way i forgot one very import thing. First thing to check on any roll over is are the brakes on. If the vehicle moves as it comes over the sidewalls of the tyres lose grip and it will crash back to the floor again. In extreme circumstances it can move that far it will tip the recovery vehicle over. Very good vidieo on Utube showing this happening.

Another little fact dont rely on transmission brake to hold vehicle they dont hold anything when set of wheels are off the floor If need be some good timbers back and front of tyres will do the job. Even on level ground you can be inadvertantly be making the vehicle tend to roll back or forth by not being exactly lined up with CG

During the initial part of the recovery it takes very little to dislodge grip on tyres. And i have had an occasion when the draught suction from a passing fridge lorry dropped one back down.

 

Nice one Cosrec keep it coming.

[cosrec]

Same truck and driver but this time it has 6 ton of flat plate strapped down in the back of it. Guess what it’s flipped over again. In side the container two things could have occurred. Either the plate is still strapped flat to floor or it has broken loose and is laid flat in the side of container. What next well one thing you don’t do is open back doors to have a look. Why because all though the vehicle is laid on a level road it may have camber on it or be resting with a corner on a kerb. If you open the rear barn doors the container will distort you will be very lucky to get them to close again. With out these doors closed and locked correctly the whole integrity of the box has gone. This is even more important when dealing with Box vans Fridges even Tilts. The ends of the box are the only strong points you have to hang on to or wrap round

It is also very dangerous if you open them as you could soon end up will a couple of tons of goods on top of you.

So in the drawing I have assumed the plate has fallen over. This now puts the CG up around 8ft from the Fulcrum It also means the CG is offset to the side but that has no effect on the recovery at this stage we are only interested in where The CG is pinning it to floor. The CG when looked at from underneath has also moved near to rear of vehicle.

When the vehicle was MT the force required to pull it over was approx 7.7 tons Now if using axles force required will be 16 X 8 / 6.5 approx 20 tons 10 tons per axle. The axles will stand this but as I have said before it’s always wise to reduce strain on rigging. So I have shown a way of achieving this with the use of three sleepers. The rigging (bridal) are fastened to the top lifting eyes a job they are more than equal to. The force required is now 18 X 8 / 9 14.5 approx tons. It takes a little effort to adjust legs of bridal to right length so that all three axles touch floor together when starting recovery but let go and re rig it will pay of later in recovery. I think this example also what a small difference in weight can make. It makes you aware what forces are involved when moving up to loaded 44 ton artics say

 

 

[ATTACH=CONFIG]36855[/ATTACH]

[Stormin]

What if the toppled truck above is a curtain sider? Surely you have to unload the goods then and through the top side curtain? Or do you take a view on the nature of the load and whether or not the curtain will support it during the lift?

[paulob1]

RAEME website, some interesting stuff here.

http://www.raeme.info/index.php

http://www.raeme.info/toc.php?cat=rec&item=1&page=p7#article

 

welding back Towing eye to facilitate recovery!

http://www.raeme.info/toc.php?cat=rec&item=1&page=p9#article

 

Now that was very interesting reading....

[cosrec]

What if the toppled truck above is a curtain sider? Surely you have to unload the goods then and through the top side curtain? Or do you take a view on the nature of the load and whether or not the curtain will support it during the lift?

Good question and i will try and answer but would like to post a little on more on roll over theory first. Suffice to say i have loathing to unload any vehicle if there is any chance of standing it up with out damaging further.

[cosrec]

Another day same truck same load same driver and Guess what it’s rolled over again. I am beginning to have doubts about this driver.

How’s about this time trying a different approach. There is access to high side of vehicle. What will it take to lift vehicle over. Calculation is same as before but remember distance from fulcrum to where winch is hung is height of vehicle Therefore 160 x 8 / 12 = approx 10.8 tons, will be needed to raise vehicle.

Must point out a couple of things

Here this it true lifting and as such you are in the lifting regulation requirements and all that entails. In order for it to be a good recovery the actual lift needs to be inline with the CG. So if you only have one lifting line some form of bridal is required. This brings about a problem if you use the top lifting eyes of container to hang to the bridal will be at a great height before you actually start to lift container and with a lot of recovery vehicles you will run short of actual available hook height to get vehicle to point of balance.

To overcome this we sometimes lift initially at back corner until about 4ft off the floor and then put cribbing in place to hold in that position this is why you need those back doors in place for strength. Then if need be move to front top corner of container and do the same there. What has this achieved? It now means the bridal can be arranged by fastening to the chassis or bottom of container with the point the hook is hung to is closer to the floor giving more chance of getting it to the point of balance before losing all hook height. It also means the wheels are now firmly planted on the floor and bearing weight. In all probability the total force now required will be a lot less then first calculated giving more chance of a good outcome. All with out lifting more than about 5 tons Hope drawing makes clearer.

So go for it and up it comes.

May have noticed in my posts I have hinted a couple of times about a good recovery. What I mean by this is the vehicle ends up stood upright with no further damage.

If you think about it once the vehicle has gone past the point of balance in the examples I have given the vehicle is out of control and is totally in the hands of the CG pulling back it down to level ground.

[cosrec]

Once the vehicle has gone past the point of balance it goes in to freefall back onto the ground. Lets bust a myth here you hear people say “when a vehicle is winched over it can hit the floor then topple the other way”. With two exceptions when winching on to level surface there is no chance of this happening. The exceptions are fridges with swinging meat and half loaded tankers. Having said that just because it hits the floor and does not roll again does not mean it’s a good recovery. To me nothing looks worse than a vehicle hitting the deck with say front axle followed a fraction of a second later by the remaining axles. It is these multiple shocks in close succession that cause the damage eg floor boards to spring out lights and lenses mirrors falling of and on occasion’s bodies to split and collapse. If when you rig up you spend time and are aligned with the CG as you winch it over all the axles will hit the floor at the same time and the suspension will absorb the shock as it is designed to do. It wont look dramatic on a video but there again any controlled well carried out recovery wont.

If you where to film the two examples that I have used the MT and laden vehicle the MT one would probably look the most dramatic with dust and muck flying about as it hit the floor. Why because the laden truck would almost certainly be have to be winched until it almost hit the deck because the steel plate is offset to the side. Secretly I would be hoping for a bit of a rough landing so that it fell back over saving me sorting it out before towing away.

If you have any doubts and have no means of doing a controlled restraint a couple of old pallets under a couple of high side wheels will smooth things out a bit.

I have also used MT 25 litre drums with bungs in stood upside down under where wheels are going to land or even a couple of tyres on top of one another.