Wind creates energy; energy that powers ships and sailboats, operates water pumps and mills. Wind is a powerful force that can tear down trees and homes. Wind is an unseen weather factor that can create snow white-outs, brown outs and driving rain. Wind should not to be underestimated.
Truckers can develop a problem opening trailer swing doors in strong wind, because no matter which direction the truck is facing while parked, the wind will affect the handling of the door. The trailer doors can rotate 270°, and wind can prohibit drivers from having control of the door. Generally swing doors are four feet wide and nine feet tall creating a sail area of 36 square feet which –very hard to control when opening or closing in the wind.
A sail area is defined as any type of surface that will generate thrust by being placed in wind. A door, in essence is a vertically-oriented wing. The more square footage in the sail area, the more power developed by wind pressure. For example, the side of a van trailer can be as long as 53 feet and 9 feet high,which equates to nearly 500 square feet of sail area. 500 square feet of sail area can have an exponentially more dramatic impact under the same conditions. Imagine a wind strong enough to jerk a car door out of your hand, and then imagine the same wind when opening large trailer doors.
There are highway signs that address wind on the road, like, “Wind Advisory: High Profile Vehicles.” The problem is exacerbated when a truck with a significant sail area travels down the highway at a high rate of speed. Pressure develops because of wind under the trailer, over the trailer, and around the trailer. The higher the rate of speed, the more effect the wind has on all these areas. A truck driver can greatly reduce danger simply by slowing down, and thus reducing the swirling effect created on those areas and the wind energy developed by spinning tires.
Logic and common sense are two faculties critical to a driver’s survival.Part of that is to understand how taking just a few minutes to inspect and secure the truck means a much safer ride, no matter what the conditions are. There is no deadline that should require a professional driver to risk life, limb, load, and equipment. If there is even the slightest chance of wind affecting the driver’s safety, then a professional driver must always follow the rules to the letter. Simplest rule, “Secure your load and slowdown.”
Professional drivers can rely on their own experience. For instance,driving a smaller vehicle (car, pickup) and passing or being passed by a larger vehicle (tractor-trailer). Hopefully the driver of the smaller vehicle noted the pressure and increased handling required to safely steer the smaller vehicle.What you felt were vortexes being developed by that larger vehicle. This example illustrates the impact another vehicle can have on driving conditions, even on a calm, windless day.
An empty trailer is far more dangerous than a loaded trailer in any wind conditions. This is one of the most critical logical points of driving a truck with a large sail, area easily impacted by wind. Because an empty trailer isn’t as weighted as a loaded one,it is more susceptible to being manipulated by other factors, especially wind. Picture a refrigerator carton empty as opposed to loaded and set in an area where wind can get to it.
Being fully aware of your surroundings and the other variables of the operation of your tractor-trailer are key to a safe drive. Remember the following and you’ll be sure to win the battle over wind.
- Know the sail area – all trucks are different, be sure that you know the details of the one you drive.
- Secure all doors and exposed items – take a few minutes to do a thorough once-over on your truck before getting into the drivers’ seat. A few minutes before hand can spare you from a disaster later.
- Check the weather report – know what you are up against before you hit the road. There’s no reason to be surprised by a freak dust storm in the Southwest or for being caught in a white out in the Badlands. Utilize information resources to avoid these areas or weather patterns.
- Pay attention to signage – Windsocks, road signs and grass that has grown horizontally are all good indicators about the types of wind conditions you may encounter in any given area. Heed their warnings and drop your speed so that wind has less force.
- When in doubt…just slow down – It’s the golden rule of professional driving.Under any circumstance: weather, road construction, restricted views or any possible hazard, simply slow down 10 mph or more to ensure that whatever you might encounter, you will have better chance to react in time and a better chance of survival.
Jay Rosenthal, a Certified Consulting Meteorologist (CCM) with AIR, WEATHER & SEA CONDITIONS, INC. of Pacific Palisades, CA adds:
An important item drivers must understand is that there are critical signs of imminent wind changes that may be visible to the driver and should be paid attention to. For instance, during approaching or even distant thunderstorms, areas of fast-moving air descending from the upper portions of a thunderstorm may, after impact with the ground, result in horizontal winds of 50-75 mph and greater that can travel for many miles away from the storm that created it. The descending air is often termed a micro-burst, and the horizontal blast of wind that results when the microburst hits the ground is often termed a gust front. This extremely dangerous condition can be recognized during the daytime by an approaching area of dust and blowing debris with markedly lower visibility. if you see that, slow down and be prepared for damaging wind gusts. Another potential sign of wind change is a column of swirling dust seen in open fields in daytime on otherwise sunny conditions. These vortices of blowing dust and debris are called dust devils. They form over sun-heated land near the borders of different colored pavements or ground cover of differing temperatures. A strong one can generate winds of up to 40 mph with strong upward winds, and they can be strong enough to do some damage to fences and farm structures. If one crosses the road in front of you, they can be a menace in trying to keep your rig in your own lane. Because they are formed by differential heating of the land by the sun, they die out rapidly once the sun goes down so you don't have to worry about them hitting you at night.
Always be alert to areas of reduced visibility in the distance. If not due to fog, they may signify areas where winds can strengthen and change direction suddenly.