Guide to Using a Snatch Strap or Kinetic Rope
There’s a heap of guides on the internet for basic things that aren’t very risky, but start with some lame warning about safety first, etc.
This is not one of those articles. For snatch/kinetic recoveries, the risk is very real. People have, and continue, to die from snatch recoveries. Please don’t treat this as some general disclaimer, but as a real warning. This is one of the only warnings we’ve ever written and if you’re sceptical about the risks, we’ve done a complete breakdown on the forces involved in snatch recoveries and how tow balls kill people when used for this purpose.
Connecting the Snatch Strap or Kinetic Rope
Never connect a snatch strap or kinetic rope to a tow ball. If you read our article linked above, you’ll know that tow balls can snap and become a heavy projectile carrying all the force that was imparted into the strap/rope, heading straight for the occupants of the car.
Rated recovery points or hitches should be used wherever possible.
If you have a Hayman Reese style hitch receiver, the best thing you can do is buy a recovery point that inserts, replacing the whole tongue and tow ball. TJM make a robust, affordable recovery hitch for bow shackles and Campboss make a very good, albeit more expensive, soft shackle recovery hitch.
When to Use Soft Shackles or Bow Shackles
Soft shackles have been hitting the market faster than car parts designed for them.
Recovery hitches, as mentioned above, provide a great solution for augmenting existing hardware on your 4WD. If you’ve got aftermarket recovery points or a rear bar such as an X-Bar by Hayman Reese, you may notice that they’re rounded, to prevent abrasion and cutting of soft shackles.
Otherwise, most stock/OEM options will have edges that are too sharp for soft shackles and you’ll need a rated bow shackle instead.
Most often, it’s the recovery point on the front of the vehicle being recovered that will require a steel (bow) shackle.
Make sure you’re carrying suitable shackles for your vehicle and even if all your gear is good for soft shackles, it can be worth carrying at least one bow shackle in case you need to recover a different vehicle.
How to Drive the Recovery Vehicle
With everything safely connected, it’s time to do the recovery. Make sure you’re in 4WD and if your vehicle has a low range, use that. You’re going to be putting a lot of load on the car, so using low range should lessen clutch or gearbox strain.
The whole point of a snatch strap, is that it allows you to build up speed, and therefore momentum and inertia, so that when the strap goes tight, it stretches. As the lead vehicle slows as it reaches the maximum stretch of the strap, that energy is stored in the strap which then contracts and pulls the two vehicles closer together. As the lead vehicle still has some momentum, this force should manifest as the second vehicle being pulled forwards. A kinetic rope is the same as a snatch strap, except it allows a greater stretch which allows more energy to be stored and is also less abrupt on the vehicles.
How Fast to Drive in a Snatch Strap Recovery
You need a great enough force to move the vehicle being recovered, but without causing damage.
Force is mass times acceleration.
The acceleration comes from how fast the recovery vehicle is moving before the snatch strap becomes taut.
Acceleration is the difference between the speed the recovery vehicle is moving at, at the time the strap goes taught and the speed it’s going by the time the strap has reached it’s maximum stretch. This usually happens over a second or less and in the event of an unsuccessful recovery, the vehicle will become completely stationary.
Mass is simply the gross weight of the loaded vehicle.
So, because we have basically no control over vehicle weight or how far/fast the strap stretches, our one variable we can control is the speed. And, because the change in speed happens so quickly (less than a second) it doesn’t actually take very much speed to create a very large force.
All that is just to say, you don’t need a lot of speed. Furthermore, too much speed can cause damage such as breaking the strap, twisting the chassis of either 4WD or even completely ripping off the recovery point, although that’s almost unheard of if it’s a rated recovery point.
Factors determining how much force is required depends on the weight of the 4WD being recovered, the type of terrain and how deep it’s bogged.
It’s almost impossible to prescribe and something you have to develop a feel for. So what it really comes down to is, if you’re a beginner, just take a cautious approach by starting slow and getting slightly faster until you achieve the recovery. The main thing to watch out for, is that once your 4WD comes to a standstill in an unsuccessful recovery, don’t tramp the throttle and bury yourself in getting yourself stuck. You will need to keep drive to the wheels after the strap has gone tight in a successful recovery attempt, but the 4WD being recovered should be starting to move a little bit at that point and what you’re mainly achieving is that the recovery vehicle doesn’t get dragged back.
How to Drive the Vehicle Being Recovered.
The main thing is to assist the recovery vehicle. When the strap or rope goes tight, you want to be driving the wheels, at a rev range that gives you enough power and torque. You don’t want to be hitting the accelerator just as it goes taut, as the engine will be bogged down under load and you’re unlikely to be in a high enough rev range where it can maintain power.
You don’t need to go crazy either and rev the tits off it.
The main thing is that you don’t spin the wheels so much that you dig yourself in deeper before the strap goes tight. If you’re bogged on the beach and are bellied out on the undercarriage, you won’t be able to dig yourself any deeper, so it doesn’t matter if you have a bunch of wheel spin prior to the strap going tight. But with that said, if you’re going flat out, as soon as you’re pulled forward you might just dig yourself back in as there’s such a difference between wheel speed and the actual speed of the vehicle. Something moderate is usually best.
How to Drive a Manual 4WD Being Recovered With a Snatch Strap
There’s not too much difference between manual and autos, but seeing as we’re here, we may as well elaborate as much as possible.
Low range and second gear is usually a good option, but some terrains; car models; and Gung Ho recovery drivers may call for 3rd gear.
Hold the clutch in and build the revs up and then let the clutch out as soon as the recovery vehicle takes off, so it’s out completely by the time the strap is tight.
How to Drive an Automatic 4WD Being Recovered With a Snatch Strap
Basically the same as a manual, but holding the brake down instead of the clutch. You can take your foot off the brake all at once, whereas a clutch in a manual should be somewhat progressive.
A benefit of autos is that if you’re doing a low speed recovery in something really bottomless like clay or a salt lake where you have to be cautious of burying yourself in further, you can leave it in drive, but without any accelerator so there’s a bit of load on the wheels to assist, but aren’t spinning and digging.