Unique Factors in Litigating the Tanker Truck Rollover Case

There are thousands of tanker trucks on the road in the United States.  When a tanker truck rolls over on the highway, the damages that result can be catastrophic. Depending upon what the tanker is hauling at the time, there may even be a major explosion.  Although a tanker truck is very similar in size and dimension to other 18 wheelers, there are several unique factors involved that have to be considered when litigating a tanker truck rollover case. Treating them like “any other truck case” could result in a truck accident lawyer completely missing out on the real cause of the rollover.

Higher Center of Gravity

Tanker trucks have a higher center of gravity than the average vehicle. This fact alone makes them more top-heavy than the typical truck trailer. Thus, when the trailer shifts as the vehicle tries to negotiate curves or stop quickly, tankers have a higher risk of rolling over than the typical 18-wheeler. Because of this increased risk, one question that should always be asked of a tanker truck driver is:

     “How much experience do you have specifically driving tanker trucks and not just 18-wheelers?”

A truck driver’s resume of driving for years can potentially become a strength for the other side when his long time driving experience resulted in a habit of driving vehicles that were not top-heavy in a way that is only safe for balanced vehicles.

What’s in the Tank is Important

Tanker trucks are different from other 18 wheelers in that they carry a liquid cargo.  Like every truck accident case, an unloaded trailer often has a longer stopping distance than a loaded trailer because it’s own weight helps slow it down.  This factor determines when and how it is reasonable for a truck driver to brake. With most 18 wheelers, this is a simple factor of trailer weight.  In tanker truck cases, however, weight is only a part of the equation. The real questions to ask are:

1) “How full is the tank?”
and;
2)“How is the tank constructed?”

Tanks and Surge Risks

Tanker trucks are never meant to be filled to the top. During transit, liquids are heated. Heated liquids expand. So, to prevent this from being a problem, tanker trucks are generally only partially filled. This is known as “outage.” When there is open space inside the tank, this gives the liquid more room to move around or “surge” as the vehicle’s momentum changes.  Stopping quickly can result in all of the liquid surging forward and effectively pushing the vehicle in the direction the driver is trying to keep it from going. Going around turns too fast or jackknifing may cause the surge to go toward the side and lead to a rollover.

Some tanks have a built-in surge “diffuser” known as baffles. Baffled tanks are tanks with dividers or bulkheads built inside them that separates the liquid contents into compartments with small holes between the compartments.  Baffles help prevent the liquid from surging literally from the back to the front or vice versa. This, in turn, helps reduce the force at which the truck may otherwise be pushed forward or back by a surge. Trucks that do not have baffles have to be extra cautious about surges, especially when there is a significant outage to allow for more shifting of the load. Unbaffled tanks are generally used for hauling consumable liquids since the baffles can make the tank harder to clean.

Driving Differences

There are many types of 18 wheelers used in interstate and intrastate commerce today. Drivers of tanker trucks need to know to try to keep their driving smoother and less choppy than they can get away with in other 18-wheelers. This helps to prevent rollover due to the higher center of gravity and surge. Oversteering, over accelerating or hard braking should all be avoided to prevent truck accidents. In emergencies, a truck driver has to be aware that any attempt to steer left or right quickly while braking is more likely to result in a rollover. Stab braking-pressing the brake down until the tires lock and then releasing and stab braking again—may be required vs slow controlled stopping techniques when you know the distance is insufficient to stop before striking another vehicle.

Conclusion

Although tanker trucks are 18-wheelers, tanker truck rollover accidents are not the same as other 18-wheeler accidents.  A truck accident lawyer needs to understand the difference in baffled vs unbaffled trailers, the effects of tank outage, surge and high center of gravity, and the knowledge and experience required to operate a tanker truck safely.  These factors can help establish whether the truck driver was qualified to drive the truck or whether he may have made mistakes from a lack of tanker truck driving experience.