Yer’ Bending the Boom

By Randall C. Resch  

A newer wrecker was parked “out of service” because its boom was bent almost fully extended. When I talked to the company’s owner about what happened, he blamed one of his new guys. 

In support of the operator, I asked the owner what training was provided. He told me about their company’s two-week training program but did not mention what steps should be taken for working side-pulls. 

New towers should be trained to understand the working mechanics of a tow truck’s boom, either a wrecker’s boom or that of a multi-stage wheel-lift. I was not convinced the new operator was adequately trained in the steps to prevent bending a multi-stage boom.  

No Big Deal Right? 

While being focused on the casualty (during recovery) certainly is a key factor, remembering that cable returns to its “point of origin” is regularly overlooked. When recovery commences, the wrecker’s boom gets raised and pushed-out with some intent to gain mechanical advantage. 

Cable then is free-spooled to stretch to the casualty from the winch, through the boom end’s “cable sheaves” and then to the casualty. In between that path is the total length of the wrecker’s boom. With free-spool knowingly locked into place, heavy winching is ready to go. But...Hold on … not so fast! 

There’s a simple premise to suggest: a stowed boom (retracted) is strongest in a mechanical sense versus that of a pushed-out boom (extended).  

Especially true to recovery trucks, when a wrecker’s boom is pushed all the way out to full extension, there is always the possibility that the boom could bend under heavy pull.  

Make it Strong 

Wrecker booms are designed to be “ideally used” in straight-line to the casualty being worked. If heavy, sideward pull becomes part of the recovery process, steps must be taken so to not damage the wrecker’s boom. 

A retracted boom is always strongest. When side winching is necessary, consider using only 50-percent extension when commencing problematic side-pull. If that means re-positioning the wrecker, doing so will help to ensure the boom isn’t bent during side-pull.  

What to Do? 

Because a casualty’s location may not allow for a straight pull, side-winching may be necessary. For vehicles that have rolled onto their sides with wheel’s facing a K-Rail, the officer on-scene may not authorize a straight-line pull. This is where the operator’s “creativity” comes into play.  

If the winch scenario can’t be conducted as a straight-line pull, attaching an opposite side, looped-chain from the boom-tip to the wrecker’s bed may help to keep the boom from moving sideways.  

Operators can loop a chain from the opposite side D-Ring and attach it to the boom-end’s upper eyelet and shackle. If no boom-end loop is available, consider a 2-inch ratchet strap attached tight in the same location around the boom’s end. 

When pull is initiated and slack tightens, the boom becomes more secure. To ensure the boom is not moving, compare the “gaps” where the boom’s first and second stages are located. If equal gaps are visible, movement is more secure. 

However, when side-pull commences, it is important to be cognizant to the possibility of tipping the wrecker if moving components are not carefully monitored. As part of my recovery courses, I am certain to point out why tow truck booms get bent. When a wrecker’s boom gets bent, it’s due to poor training, operator error and improper set-up.