I have never seen a piece of powered mobile equipment become so popular in such a short period of time, as rough terrain variable reach forklifts; otherwise known as telehandlers. In the past ten years, telehandlers have become the darlings of the construction industry, and for good reason. These machines are powerful, versatile, practical, and readily available as the number of manufacturers and models has exploded over the past five years or so.

Technically speaking, a telehandler is considered a (ITA*) class 7 powered industrial truck, which means it is a rough terrain forklift, but a forklift in name only. Any similarity between a telehandler and a vertical mast type of forklift literally ends on sight, not to mention in operation. Let’s run through a few of the more significant differences between the two.

The Boom

Being fitted with horizontal boom rather than a vertical mast gives a telehandler an entirely different look; I once saw one with a jib attachment that, at a distance, looked more like a mobile crane than a forklift. The boom is capable of elevating to an angle from horizontal of approximately 70 degrees, give or take a few, and can also telescope (extend/retract) to lengths of 30 feet and beyond, depending on the model. This ability of the boom to telescope has led to telehandlers being referred to as “zoom booms,” a nickname that has caught on rather well with operators.

Another (optional) boom related function is called “transaction.” Telehandlers with this option have a boom that is mounted to the chassis in such a way that, when activated by the operator, allows the entire boom to travel forward and back, typically for distances up to 8- feet or so. One significant advantage of this function is that it allows the forks to be inserted under or withdrawn from a load cleanly (no snags), regardless of the boom angle.

Frame Tilt

This is a unique feature common to telehandlers. The operator may activate controls to alter the lateral (side to side) angle of the frame 10 to 15 degrees in either direction from horizontal. Mounted in the cab is a curved, liquid filled tube (frame tilt/level indicator) with a bubble indicator similar to a carpenter’s level that indicates the lateral angle of the frame relative to the ground; a very handy device to use to level the frame before elevating the boom on rough terrain.

Steering

Some telehandlers have rear wheel steering similar to a vertical mast type unit however most have three steering options which the operator may select: front, circle and crab. If the operators choose the “front” steering option, only the front wheels react to the movement of the steering wheel. If the “circle” steering option is selected, the front and rear wheel react in opposite direction giving the unit a surprisingly tight turning radius for its size. If the “crab” steering option is chosen, all four wheels react in the same direction allowing the unit to move diagonally over the ground (see below).

The Carriage

Like conventional forklifts, the lifting attachment (and there are many) can be tilted forward and back from horizontal, although the amount of forward tilt possible far exceeds that of vertical mast type forklifts. In fact, most telehandlers are capable of tilting forward to a point where the carriage is parallel with the ground! In addition, many units have rotating carriages as well which allow the operator to adjust the lifting attachment radially, meaning the load can be tilted side to side as well as forward and back.

Load Capacity

Determining the load capacity of a telehandler is a completely different exercise than it is on a vertical mast unit. Since the capacity of the unit is dependent on such things as: boom angle and extension, amount of boom transaction deployed (if applicable), whether the unit is lifting on outriggers or rubber (tires), which lifting attachment is used, grade, wind, etc., the operator has much more information to consider. Telehandlers often have several load charts (see image) that the operator must reference to determine the load capacity of a given lift. Capacity may differ by thousands of pounds depending on the configuration of the boom and the unit in general.

Operation

With so many options and systems unique to telehandlers it is extremely important for operators to receive equipment specific training and evaluation. The best piece of advice I can offer that will move you in that direction is, READ THE MANUAL! The manufacturer’s operating manual is a rich source of equipment specific information and a must for any operator to become intimately familiar with, well, maybe not intimately but you know what I mean!

I once delivered an operator training program involving a telehandler and discovered a number of things in the manual that I may never have known if I didn’t look, such as:

• The boom would not elevate unless the outriggers were deployed.
• At boom angles greater than 40 degrees, the axle oscillation system locked up, the transmission shifted to neutral, and the park brake was automatically applied.
• If the direction selector was activated in less than three seconds after start-up, the unit would not move and would need to be re-started in order for it to get through its self diagnostic systems check.
• Do not travel with the boom elevated.
• Do not, repeat; NOT, activate the frame tilt with the boom elevated.

OK, the last two I already knew, and the other items may be common knowledge for those that are used to working with this equipment, but just imagine the adjustment that an operator of a vertical mast type unit would have to make before he/she could safely operate a telehandler. Just the dynamics involved with how the machine “feels” during operation takes more than a bit of getting used to. By the way, it is interesting to note that none of the operators in the training program I mentioned even knew what frame tilt was or that their machine had it. Scary stuff!

All things considered; telehandlers are wonderfully versatile, practical machines. Speaking as a trainer however, I would be remiss if I did not add a cautionary note to warn any potential users and/or operators out there; telehandlers are completely unique in design and operation from conventional vertical mast forklifts. This means that operators of these units require uniquely detailed and equipment specific training, as well as plenty of hands-on practice. Like any other type of powered mobile equipment, it is only as capable as its operator.

*Industrial Truck Association