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| Chaffin Luhana LLP

After an airplane crash, investigators often focus on finding the “black box,” which is an event data recorder (EDR) that can help provide important clues as to what happened right before the plane went down. Many commercial 18-wheeler trucks and tractor-trailers have similar EDRs that track information like fuel economy, engine problems, how long the truck traveled at certain speeds, maintenance history, and much more.

For individuals who were injured in an accident with a large truck, the EDR may hold important information to prove negligence or gross negligence in a personal injury lawsuit. The problem often lies in retrieving that information before it is lost, destroyed, or withheld by the trucking company.

Commercial Truck Crash

Large Truck EDRs Require Unique Equipment to Access Data

Truck manufacturers began installing EDRs in large trucks in the late 1990s. EDR’s are still not required by law, but several manufacturers of heavy trucks include them. Most EDR’s record and store less than a minute of data, but when a crash occurs, that will be the data that was gathered right before the accident.

In the trucking industry, the data gathered by these devices can be manipulated more than it can be in the automotive or airline industries. Large truck manufacturers, owners, engine suppliers, and fleet operators have the option of changing the EDR data retention policy, adjust trigger thresholds, or even disable the EDR’s completely.

Accessing the data in any particular EDR may also require specialized equipment. Engine suppliers, for example, require their own software for downloads, and some manufacturers won’t even allow access by other manufacturers or third party software. Indeed, the make and model of the truck itself often may make little difference when trying to retrieve data about an accident, because the EDR is often from the engine manufacturer.

Using EDR Data Plus Other Evidence Can Create a Complete Picture

Black box data, once it is properly retrieved, can shed light on what the driver was doing prior to the crash. Putting the story together, though, requires expertise, and an ability to combine the EDR data with other evidence from the crash scene.

Truck EDRs capture vehicle speed and throttle position, but typically don’t capture vehicle acceleration or change in velocity, which can make it more difficult to determine speed change right before the accident. Analyzing the EDR data together with the roadway markings, the mass of the vehicles involved, and the vehicle damage can help complete the picture.

The EDR will also reveal any maintenance issues, such as low tire pressure, and potential driver errors such as sudden brake application, traveling at high speeds, using the cruise control, or exceeding regulated work hour totals.

All of this information taken together can be used to create a computerized reconstruction of the accident for a jury. Data from the black box also may help show that the defense’s assumptions are inaccurate, as well.

Preserving EDR Data

Obtaining the data from the EDR can prove difficult in some situations. Sometimes, the data is lost because the EDR or engine control module was damaged in the crash, or because the accident data was overwritten by other data that occurred afterwards. If a driver drives the truck after the crash, for example, the black box data can be lost. The truck should be towed and the date preserved. My office, as a habit, immediately sends out a vehicle and data preservation letter in all commercial trucking cases.

As mentioned, downloading the data can prove challenging, and may require specialized equipment. If possible, engage experts to download the data at the scene of the accident so they can also gather other information from the crash scene at the same time.

Finally, the truck company may refuse to preserve the data, or they may insist on repairing and restoring the truck for duty in order to avoid losing money. In these situations, the plaintiff may need to get a court order requiring the company keep the truck still until the EDR data can be properly downloaded.

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