Modern recovery equipment is extremely sophisticated and manufactured in quantity throughout the world. However up until the mid-seventies a large proportion of the equipment in use was homemade, often just consisting of a ridged jib and a simple
block and tackle. After both World Wars, a number of army surplus vehicles were purchased cheaply by operators and converted to civilian use. This was especially true for recovering
trucks and other commercial vehicles. In 1918,
Ernest Holmes of
Chattanooga, Tennessee patented the first American commercially successful vehicle recovery crane, and its modern descendants have changed little since. Around the same time, recovery cranes were being produced by Weaver Manufacturing and Manley. In Europe, Harvey Frost Ltd of Great Portland Street, London, started selling recovery cranes made by Ernest Lake from around 1905. The first major change to these crane designs would take another fifty years and came from Sweden. Olaf Ekengard, under the trade name EKA, designed and marketed a crane that lifted from underneath the subject vehicle. Nearly all lift and tow vehicles today use variations of his idea, while traditional cranes are kept for specialist work. A typical modern recovery fleet will operate a great diversity of different types of recovery and support vehicles. This will include basic service vans, mobile workshops, lift and tow vehicles often called
tow trucks, transporters and trailers. It is not uncommon for them to also operate mobile cranes, road going fork lifts, articulated tractor units and incident support vehicles. In some locations they may also operate off-road vehicles and even boats. All will have specialised vehicle body styles, to best achieve the job they were designed to do.
Types of tow There are five main methods of vehicle recovery:
Soft Used for very short distances where a rope, chain, or a length of webbing is attached to the casualty, which must have a working braking system as it will be used to slow both vehicles. This can be dangerous, unless both drivers are competent enough to do it. Although many people believe this is illegal on motorways it is not in Europe, as long as the relevant trailer laws are complied with, i.e., correctly configured lights and signing, observing trailer speed limits, etc. In the US this is simply called a "flat tow", and it is not common practice to use the brakes of the rear vehicle to stop both vehicles. As typically a car is being flat towed because the engine won't run, and without a running engine the power brakes don't work, it could be dangerous as well as difficult to slow and stop two vehicles using only the brakes that only half function. Instead, it is typical for the towing vehicle to drive normally, but avoiding sharp acceleration or braking. All the person driving the rear vehicle has to do is gently apply the brakes whenever the tow chain begins to slacken, and anticipate stops so he or she can drag the brakes and come to a halt without excessive slack in the chain. This still requires a relatively skilled driver, as neither the power brakes or
power steering will function, and you must take care to steer wide in sharp corners and never allow the chain to slacken, or it may get jerked and broken, or worse, drag underneath the vehicle and possibly cause damage or even loss of control.
Rigid (or bar) Used for very short distances where a solid metal bar is attached to the casualty. Used mainly with commercial vehicles, which often have a towing eye in the front bumper. In the case of cars and light vans, the towing vehicle can be used for braking, if the bar is kept straight. With commercial vehicles, it is common to connect an air feed to the casualty to allow the tow vehicle's brakes to also operate the casualty's brakes. In the US, both "soft" and "rigid" tows are called "flat tows", although if a rigid bar is used it may be called a "bar tow".
Lift tow (suspend tow crane) Now rarely used, but for many years the only way to move a disabled vehicle without using a low loader or trailer. Chains were attached, usually around the casualty's suspension, and some form of packing (often a seat squab or tyre) was inserted between the lifting frame and the casualty. This frame was lifted by means of a pulley until the casualty’s wheels were clear of the ground. An 'A' frame was normally used to keep the casualty from running into the tow vehicle on braking.
Lift (underlift) The lift tow is the most common modern method for short distance transportation. The casualty is winched onto a lifting grid and then raised by lifting the grid, with the casualty’s tires strapped to the grid. The grid is shaped like a large pair of spectacles, which accounts for the common name of this type of vehicle, the speclift or
spectacle lift. With commercial vehicles, it is more common to use a set of lifting forks to attach to the suspension, axle or chassis of the casualty. In many cases, e.g., with automatics, it is the 'driven' wheels that need to be lifted. This will sometimes result in a rear lift, if the driven wheels are at the rear. In this case the casualty's steering
must be locked in the straight ahead position.
Transportation (total lift) The preferred way to travel any distance. Usually the vehicles are purpose-built low-loading 'Transporters' although trailers are still used, especially for the movement of
coaches and
buses. Some transporter designs are very sophisticated, with bodies that 'demount' to give a low loading angle. This is especially useful for sports cars, etc., with low ground clearance. There are also transporters with totally enclosed bodies, used for example for the transportation of prestige vehicles, or vehicles involved in crime that are going for forensic analyses. In the sites it often common to see 'city loaders,' a type of transporter fitted with a cradle to totally suspend a vehicle for loading. These are often used to move illegally parked vehicles.
Variations For a long while, it was common to use 'dollies' to recover vehicles. These were cranes and underlifts as above, but mounted on a two-wheeled axle. They were designed to be towed behind a suitable towing vehicle. Another portable device was a crane, which clipped on to an articulated tractor unit's fifth wheel coupling. Popular in the seventies and eighties, they were cheap to buy (compared with a purpose-built recovery vehicle) and appealed to fleet operators, who could use them to recover their own vehicles. Total lift dollies were carried by some spectacle lifts to place under the wheels at the opposite end to the lifted wheels, thereby converting the half lift into a total lift. These are used, for example, when a vehicle has had an accident and both ends are damaged.
Other equipment Modern recovery vehicles come with a bewildering number of accessories. These include power units to supply air for power tools or pumping off vehicle braking systems, etc. Generators supply 110 or 220 volt mains power for floodlighting, tools, etc. There are different shaped forks for attaching to lift points, or for modifying standard lifting devices to allow them to transport motorbikes. Most vehicles will be equipped with an assortment of lifting strops or chains and webbing to secure loads. A special form of
webbing called a
snatch strap is sometimes carried to assist with vehicles that are bogged down in mud, etc. Nearly all vehicles will be fitted with 12 or 24 volt 'jump start' or 'booster' sockets to start other vehicles with discharged batteries. Most will also have power
winches to load the casualty, or for dislodging stuck vehicles. Some larger recovery vehicles will have two (or more) winches capable of pulling up to 30 tons per line. These will be used to winch back vehicles that have left the roadway. Some vehicles are fitted with luxurious multi-seat passenger compartments called crewcabs. These often have DVD players and even drink machines, for the benefit of the casualty's occupants on their trip home. Different types of rotatable cranes are sometimes fitted for lifting vehicles out of ditches, etc. Heavy lifting cranes are sometimes fitted and can be used for example to winch overturned vehicles back on their wheels. Some recovery vehicles are equipped as mobile workshops or service vans. They will carry a large selection of tools, spares and garage equipment, such as jacks and vehicle stands. In recent years many have also been equipped with spectacle lifts that fold away inside the rear doors. The advantage of this system is if the vehicle is not repairable, it can still be recovered without sending a second vehicle. 'Righting' an overturned vehicle, especially one that is not badly damaged, has become a science. When a commercial vehicle ends up on its side there will often be little clearance to slide lifting strops underneath it. Even if this can be done, the use of strops can cause further damage and are often not the right way to start a lift. To solve this problem, recovery operators often use air bags to at least start the lift of the casualty. A number of bags can be used and this spreads the load throughout the length of the vehicle. Only a low pressure is used, which means in the event a bag is punctured, it just gently deflates and does not explode. Once the casualty is above 45 degrees, a normal winch can be used to finish the job. It is not uncommon to use a second winch from the opposite side, to gently lower the casualty once it has passed the point of balance. It is also quite common for recovery operators to be asked to move 'other' items. The picture at right, taken in the late eighties, shows a recovery crane lifting a
Hawker Hunter aircraft before transporting it to
Brooklands Museum in Weybridge, England. == Stolen vehicles ==