Basic Truck Accident Investigation

The Truck Safety Expert's Guide To Thoroughly Investigating A Trucking Collision

It is certainly a fact that trucks are extremely different from other vehicles and obviously so -- they're bigger. They also use the public highways for a company's economic gain. When trucks cause accidents, the results are usually disastrous. Each truck is different, as is each accident. Therefore, each accident must be investigated on an individual basis. When investigating trucking accidents, parameters need to be set out. Encompassed within those parameters is the necessity of investigating, dissecting and analyzing the physical evidence at the scene, as well as the technical evidence that is attached to the equipment, or as part of the equipment's development. It is also vital to use those same techniques to investigate the company, drivers, shippers, and anyone else who might gain economically from the movement of the truck. All of the entities should be investigated and explored to see if they are partially responsible for the safe operation of that equipment, its load, the driver and so on.

As I mentioned, trucks are different and it is important for you understand how they connect, operate, and function. The most common commercial motor vehicle involved is the 18-wheeler, so for purposes of this article, I will discuss that vehicle and its components. The 18-wheeler wheeler is comprised of a tractor and a trailer, both of which are separate commercial vehicles. The trailer has 8 wheels, and the tractor has 10 wheels. The tractor has a coupling assembly known as the fifth wheel, and the trailer's coupling device is known as the kingpin. The vehicles are connected together by latching the kingpin to the fifth wheel. Once connected, these latching components create a hinge. The hinge allows the unit to move and certainly turn, as everybody has witnessed this phenomenon at a corner. Trucks do bend when they have hinges, and the hinge mechanism can play an important part in the mechanics of an accident. For example, a driver can yank his foot off the throttle, and the trailer can push the tractor into a jackknife. Similarly, if the tractor has a Jake brake, which is an engine retarder, it can which control the speed of a truck. This is accomplished by creating resistance down to the drive train of the tractor. Since this is on one side of the hinge (5th wheel), the trailer on the other side of the hinge can push the hinge into a bend, resulting in jackknife. Therefore, any investigation should include an inspection of the fifth wheel and kingpin.

As part of this investigation, one should explore whether the fifth wheel was adequately lubricated. If the fifth wheel is not lubricated sufficiently, the hinge will be very stiff, and this will cause the driver to have problems steering the combination. In some instances, the drivers may overreact, and this could lead to an accident. Thus, as part of your investigation, you will want to obtain lubrication records and inspection records, as well as statements and testimony as to inspection.

In addition to problems involving the coupling of the tractor and trailer, there are numerous aspects of the components of the equipment that can be a causative factor. For instance, a steering problem can also be caused by the suspension failing, breaking or being too light or too stiff. There are certainly other components that can cause problems. The equipment can have an air ride tractor, air ride suspension and an elliptical spring suspension on the trailer, and therefore you can have two different problems in terms of how the suspension reacts on the same combination. For example, let's consider a semi truck. These trucks typically have an air ride suspension, which is a compensating suspension which levels or equalizes the pressure of the suspension in order to support the load. Assume it is parked and ready to dump in a slightly sideways attitude (ground slope). The compensating pressure of the air bags as the dump is being made can cause the frame of the tractor to change its "attitude," which, in turn, can cause the dump truck to roll over. Since air suspension is a compensating suspension, a tractor with air ride, pulling a trailer with elliptical spring suspension can develop a different attitude or "stance" in a curve or a turn or any combination of those highway designs simply because of the difference in design structure. Therefore, any investigation should include finding out what type of suspension exists, an inspection on each component of the equipment, and what the specifications are for that system. IN addition, you will want to inspect the suspension to explore the viability and/or the condition of the equipment.

An unbalanced brake system can be a factor in lots of accidents. Unbalanced braking system can affect the steering, control, and stopping distance of the vehicle. Unbalanced means that you have a greater stopping ability on the tractor than you do the trailer, or vise versa. The braking system may also be unbalanced on a right-to-left basis or fore-to-aft. The right to left means that you can have a wheel on the left side of the system or axle that's out-of-service, meaning that it does not work. If this happens, obviously you're going to have a pull on the right side more than you will to the left. Therefore, as part of your investigation, you will want to examine the condition and adjustment of the brakes on both the tractor and the trailer to see if any conditions exist that would cause them to be unbalanced. You will obviously also want to review all of the maintenance and repair records.

You should also consider the condition of the tires, including their position and pressure, which this can have an impact on how the truck operates and functions. For instance, envision an axle with 4 tires on it. Each tire has a tire pressure of 100 pounds, and each tire and wheel will be "rated" for 6,000 pounds. So then, in theory, that axle and those 4 tires are rated for 24,000 pounds. If the tire pressure in one of the outside tires is reduced by 60 pounds, then the rating of that tire would also be reduced, and it would be much less than the other 3 tires. If the vehicle attempts to make a turn, the axle will be significantly less capable of supporting the maximum weight of the vehicle, and this will cause a larger footprint (tread on the ground), much more pressure on the sidewall, and much more pressure on the inner wheel, which can lead to accidents. Thus, when investigating and inspecting the equipment, the tire condition (how good is it), the position (outer or inner), where the axle is placed, and the tire pressure should always be noted.

In addition to the actual mechanical operation of the vehicle, you also need to other things that may have interfered with the drivers' ability to safely operate his truck. You will want to examine the condition of the cab of the truck where the driver lives and whether or not the driver puts materials or equipment or signs or toys in the window of his passenger side that restricts his view into his mirror or on the dashboard. The investigation should include the line of sight of the driver, what that driver can see out of the mirrors, and where the blind spots are on the truck The mirror placement is absolutely a major part of driving. The driver should look in the mirrors every thirty or forty seconds while driving down the road in order to keep track of what is around that particular vehicle. The driver must know the blind spots that they exist, where they are, whether or not he is moving in to a blind spot. The investigation should also show where the blind spots are.

The investigation also cannot be limited to an inspection of the truck and its parts. You must also investigate the driver, his qualifications, his character, his experience, and how he got behind the wheel. You must also investigate the qualifications of the company itself and how the company system works needs to be explored. Your investigation of the company must include how the computer contacts, recruits, and interviews drivers. You also want to explore how the company trains and monitors drivers, as well as how they monitor drivers and determine whether they are qualified to drive their vehicles. They should also have a system for auditing their drivers. Essentially, you want to find out all of the things that the company does to arrive at the decision that this driver can now drive this truck in this set of circumstances. Drivers need to be investigated as to qualifications -regardless of experience. It's quite common for a driver to be driving for twenty years in the trucking world and still not be able to pass a road test, because they cannot answer the questions about how the equipment works, what the regulations mean, and can't tell you about hazardous conditions and their responses to those conditions. They may well be a driver that has driven 19 years on flat land and now being dispatched into the mountain areas of California, as an example.

If maintenance becomes an issue, then certainly the training of maintenance and shop personnel becomes an issue. The training of the safety department and its personnel is always important. The investigation must go deeply into the company in terms of how their system works. It's important for the investigator to examine everything in the company that deals with drivers, mechanics, maintenance, owners/operators, dispatch, safety, company procedures, and so on. So all of these investigative things need to be a part of the investigation and the investigator's portfolio.

The modern trucks are getting more and more sophisticated. Part of that sophistication began to develop in the 1992 models (this is also true of automobiles). At that time, the truck began having Engine Control Modules (ECM), which are motor mounted computers. The ECM's came into existence because the government, in an effort to reduce air pollutants, mandated that engine manufacturers have better, more efficient engines and fuel systems. The ECM does this by distributing fuel in the engine and monitoring the engine to see how it is doing. From the time the engine is first used, the ECM will keep a record of how many hours the engine runs, at what speeds, how many hours the engine idles, and how many hours the engine is off. This can give the manufacturer a chance to track the efficiency of the engine as time goes by -as well as the treatment that engine gets by the "end user".

In later models, such as '95 and '96 and the later era of time, there are more and more modes put into the ECM software. One of them is commonly called the Pro Driver mode, although different manufacturers have different names for this. If the engine has a hard stop or sudden deceleration that exceeds seven feet per second, this mode will create a recording of precisely when that happened and what the speed of the truck was. Typically, it will also go back and save the last forty seconds that took place immediately prior to the hard braking. That record stays in the computer until there are two more hard braking applications. After a third hard braking application, the first one will be deleted. Keep in mind that all the engine manufacturers have ECM's, but they contain different modes, and different modes recorded different information. Therefore, as part of your investigation, you will want to obtain the specifications for the ECM that was on the truck involved in the collision. In general, the later the model, the more information you're going to have. You will then need to have someone download that information from the ECM, and generally, the engine manufacturer in the shops will download them. However, Detroit Diesel has a system where they will recommend people around the country who have gone to their classes and can download the engine information so you can have that kind of information very quickly. Your job as the investigator is to discover what type of ECM was on board and what information can be downloaded from it. In doing this, be forewarned -- sometimes you'll be disappointed because the modes will not contain the information you are seeking. For example, if you have a collision that does not involve a rapid deceleration, such as a sideswipe, the ECM might not be activated, and therefore, there is no information to retrieve.

Some trucks also contain an on-board locating system. The most common and well-known system is Qualcomm. This is a global positioning system that geographically tracks where a truck is at any given time. The Qualcomm system also allows the driver to communicate with his dispatcher, and also serves as an on-board fax machine. The driver can hit an emergency button indicating that he has an emergency, and then dispatch in theory can respond to that. It's important to realize that generally the companies don't download that information and have it available for an instant investigative inquiry. In fact, they aren't required to under the regulations, and for the most part, it is not practical for large companies who run thousands of trucks to download the ECM material or the Qualcomm material. Therefore, if there is a collision, you will need to act quickly to obtain this material. If you don't get it within 30 days, there's a high probability that the information will be deleted.

You will also need to act quickly to obtain other documents, including the driver's qualification file, logs and payroll records. All of those things are computer monitored or generated need to flagged. (A complete list of all of the documents that you will want to obtain is attached to the end of this article). Of note, the GPS system can indeed by virtue of comparing geographic positions, be used for log auditing, and indeed the speed of the equipment. Auditing can be held, because the truck did have an incident or accident and the driver needs the support for his story and/or the company needs to investigate to insure that they have an obligation to whomever they had the accident with or the training of the driver and so on.

I don't think that I could emphasize enough that the activities concerning an accident investigation should be done quickly. Many times you don't get the information for a year or so, and the company has had an opportunity to indeed hide behind the regulations that say they can remove the documentation. There isn't any regulation that deals with Qualcomm systems and saving the data that I know of. The importance now of this message is go quickly, to get the right investigators, to gather as much data as you can, to spend as much as time as you can gathering that information, write that letters that hold the equipment for inspection. Those are all legal things that you all know very well, but they're also things that I can recommend. If the truck had an accident at eight o'clock this morning I would like to be looking at the truck at nine o'clock this morning if that's possible. Obviously that's not possible in most cases, but never the less it would be a nice thing to think about. The quicker you get to it, the better the evidence most of the time.

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