This case involves an automobile that unintentionally accelerated, causing the vehicle to strike a tree and injure the driver, causing the driver to sue the car dealership and manufacturer under state-defined Lemon Laws. The plaintiff, a forty-three-year-old female, was driving on a rural road when her vehicle suddenly accelerated. The plaintiff was unable to stop the acceleration, and she lost control of the vehicle as it veered off the road and struck a tree. The plaintiff sustained a concussion and multiple lacerations on her face and arms. A specialist in vehicle accident reconstruction and with ACTAR certification is considered to opine on the case.

Many vehicles have an electronic throttle system. If the control module sends an errant signal, the throttle can open causing the automobile to suddenly accelerate. The software to analyze this potential error, however, is usually owned by the car manufacturer. Therefore, the scan will have to be conducted by the vehicle manufacturer. Once the subject vehicle is turned off, the accelerator will close and return to its pre-crash condition. A post-crash mechanical inspection will probably not be able to show the open throttle. A speed calculation would have to be based on the download or crush deformation. This sudden acceleration problem did exist with other types of automobiles, and NHTSA investigated the error. I am a traffic accident reconstruction specialist with over 1800 full-scale collision investigations and component defect evaluations. I am also a certified court expert with over twenty-seven years experience in collision reconstruction, defect investigations, biomechanical analysis, and injury causation studies.

1. What caused the vehicle to suddenly accelerate?

Location: Pennsylvania B.S., Safety Science, Indiana University of Pennsylvania Certified: Traffic Instructor and Child Passenger Safety Installer in Pennsylvania Member, National Safe Kids Organization, Society of Automotive Engineers, National Association of Professional Accident Reconstruction Specialist,, International Network of Collision Reconstructionist, American Academy of Forensic Science Former C******** R************* S********* f** t** N******* H****** T****** S***** A************* Former C******** R************* S********* f** D******* C***** F**** A******* T*** Current C******** R************* S********* -* P****** P******* Published more than ten papers regarding accident reconstruction and injury analysis

This expert is a traffic accident reconstructionist specialist with over 1800 full-scale collision investigations and component defect evaluations. He is a certified court expert with over 27 years experience in collision reconstruction, defect investigations, biomechanical analysis, and injury causation studies.

Unintentional Acceleration Leads to Serious Car Accident

This case involves a nearly fatal ATV accident. Both the plaintiff, a twenty-nine-year-old female, and the defendant, a twenty-two-year-old male, were riding ATV’s, individually, on designated trails at a local park. There was one part of the park which featured relatively blind turns, with rocks and uneven terrain on a narrow trail. There were numerous warning signs indicating that vehicles in that particular section should not go above thirty miles per hour. On the narrow trail, the two ATV’s struck each other in a near T-bone crash. The plaintiff’s ATV hit the nose of the other and landed upturned, throwing her from the vehicle. The plaintiff suffered multiple lacerations, three broken bones, and a concussion. The impact of the collision misdirected the defendant, however, into a tree. Among other injuries, the defendant received major head trauma and was left in a coma for two weeks. The plaintiff brought suit against the defendant, alleging that he was driving recklessly and at an unsafe speed. A vehicle accident reconstruction expert with ACTAR certification was needed in the case.

While some commonalities exist between ATV and other vehicular accidents, there remain some very specific differences. In any accident reconstruction, the physical evidence must be evaluated with environmental factors and the application of engineering and scientific principles. Accurate reconstruction may require the use of three-dimensional imaging, engineering principles, mathematical calculations, and physics models. Challenges specific to recreating ATV accidents largely stem from the varied terrain and conditions that exist on many ATV “trails.” In order to discern the details of an accident, the nature of the terrain, the time of day, and (as closely as possible) the exact weather conditions need to be examined. In this case, the preceding paths and the wooded environment, in addition to the standard analyses of the vehicles and riders, need to be examined closely to discover the speed of the vehicles, the drivers’ range of vision, and their ability to maneuver.

1. How can the specifics of an ATV accident be discovered, and what challenges exist?

Accident Reconstruction Needed in ATV Accident

This case involves a rear-end collision that occurred on an interstate highway. The plaintiff was driving down the highway in a black tractor-trailer traveling approximately sixty miles per hour. The plaintiff’s speed was determined by the data recovered from the data control monitor that was installed within the truck’s engine. The plaintiff was struck from behind by another tractor-trailer, which hit him at such a faster speed that he lost control of his vehicle and swerved into a large ditch. As a result of the accident, the plaintiff sustained fatal injuries and died three weeks after the event in question. The defendant was charged with reckless driving, and there was a dispute as to the speed of the defendant’s truck at the time of the accident. A vehicle accident reconstruction specialist with ACTAR certification was sought to opine on the case.

Accident reconstruction with larger vehicles (RV's, tractor trailers, or larger SUV's) is usually a more challenging calculation due to the increased number of variables. For tractor trailers, it is easiest to begin the analysis by understanding that there are essentially two components of the tractor trailer, the tractor and the item(s) being towed. By separating the two components, the effect of any impact can be discerned. Looking at the individual model of the truck, its usage (mileage and any custom modifications), the road it was on at the time of the accident, and the size, sex, and health of the drivers are critical to determining accident specifics. Regarding the item being towed, the shipping records indicating the exact items being shipped and the storage unit towed behind the truck are also important for any reconstruction calculation. By taking these factors into account, I can run numerous simulations to discover closing speed, equivalent barrier speed of the accident, crushing forces involved, injury biomechanics (G's), kinematics experienced, and overall speed at the time of the impact.

1. How can the speed of a tractor trailer be determined?

Location, California B.S., University of Michigan, Ann Arbor Graduate Studies, University of Michigan Certification: AMA, CMA, CRC, CMC, AME, IKF, WERA, SCK, WKF, PADI, AAU Member, Society of Automotive Engineers Member, Forensic Witness Association Former R******** S****** P****** M****** M******* Former P****** a** B************* T*** E******* G****** M***** S***** R******* a** D********** L********* Current B************* E******* a* a m**** e********** f*** Current C** a* m**** a******* r************* f***

This scientist-engineer has over 25 years of experience in automotive safety research and development. In addition, he has 35 years of motor vehicle accident reconstruction with experience in analyzing defects with various types of truck specifically involving chassis design. He has been involved in several successful expert witness testimonies regarding various truck impact cases.

Accident Reconstruction Needed in Tractor Trailer Accident

This case involves a wrongful death suit in which the plaintiff-decedent was driving a motorcycle at a high rate of speed. The plaintiff was also carrying a passenger. As the plaintiff and his passenger went over a 4 lane bridge, the defendant-decedent was driving a pickup truck and pulled out in front of the motorcycle after driving through a stop sign. The plaintiff applied his brakes for 100 feet, but he was unable to avoid the pickup truck. The plaintiff’s motorcycle struck the side of the defendant’s pickup truck, killing the defendant-driver, the plaintiff-motorcyclist and the motorcycle’s passenger.

The auto insurance company insured all parties and made the determination that the plaintiff-motorcyclist was grossly at fault, given the plaintiff’s high speed at which the motorcyclist was traveling (45 MPH). In light of this determination, the insurance company refused to pay for the life insurance policy. The insurance ntwork company retained an expert in vehicle accident reconstruction.

Based on the assumption that the motorcycle skidded about 100 feet, it may have been possible for the motorcyclist to stop prior to striking the pickup from an initial speed of 45 mph, with a 0.7g deceleration rate. This is a high deceleration rate and many motorcyclists are reluctant to apply the degree of braking necessary to achieve this on the front wheel. Such a rate would be possible on dry roads, and an even greater rate is possible for skilled riders. A more reasonable deceleration rate (which would still be aggressive braking, but which would rely more on rear wheel braking) of 0.5g for 100 feet from 45 mph would result in a speed at impact of around 22 mph, which is a severe impact, but which would be potentially survivable for all parties. In short, assuming dry road conditions, this collision was potentially avoidable with 100 feet of stopping distance from an initial speed of 45 mph by braking alone. With more than 30 years of automotive engineering experience, this expert has dedicated his career to the field of accident reconstruction. Holding Masters and Doctoral degrees in automotive mechanical engineering and highway safety, he is a recognized expert whose clients have included U.S. federal, state and foreign governments. He has extensive court experience, having been either deposed or testified in approximately 200 trials. He has also acted as an automotive engineering consultant in more than 3,000 vehicle crash cases.

Can you determine whether, at the speed he was traveling, it was possible for the plaintiff, given his position to have stopped in time to prevent the accident?

Location: Potomac, MD M.S.M.E., Moscow Automobile and Highway Engineering Institute Ph.D., Moscow Polytechnic Institute Continuing education in Vehicle Dynamics, Traffic Accident Reconstruction, and Engineering Dynamics Member, The Society of Automotive Engineers Member, The National Association of Professional Accident Reconstruction Specialists Published, 30+ books and technical publications Current F****** a** P******** o* p****** v****** a******* r************* a** e********** f***

With over 30 years of automotive engineering experience, this expert has dedicated his career to the field of accident reconstruction. Holding Masters and Doctoral degrees in automotive mechanical engineering and highway safety, he is a recognized expert whose clients have included U.S., State and Foreign Governments. He has extensive court experience, having been deposed and testified in approximately 200 trials, while he has acted as an automotive engineering consultant in more than 3,000 vehicle crash cases.

Accident Reconstruction Required in Deadly Motorcycle Crash

An accident reconstruction expert witness for the defense advises on a case that involves a collision between two tractor trailers that were traveling on an interstate. As the trucks were side-by-side, the defendant’s truck was traveling at 63 mph in the right lane. The plaintiff was traveling about 60 mph in the left lane. The defendant, who says he suffered a medical event, crossed into the plaintiff’s lane, sideswiping his truck and allegedly causing cervical disc herniations and a right rotator cuff tear. The plaintiff’s trailer was pushed substantially to the left across multiple lanes. He was able to straighten out and brake to a stop after the collision. Neither truck struck the center median, rolled over, or ran off the road. The plaintiff sued the offending driver and his trucking company for negligence, and hired an accident reconstruction expert with ACTAR Certification to opine on the matter.

Using the Engineering Dynamics Simulation Model of Automobile Collisions (EDSMAC4) accident reconstruction software, I determined not only the most likely accident scenario, but also the most severe accident scenario that could have occurred without either tractor trailer striking the center median or losing control. In my opinion, the lower end of the range was most realistic because it was consistent with the defendant passing out due to a medical event. The high end of the range was not only inconsistent with the defendant suffering a medical event, it resulted in a simulation in which the plaintiff’s trailer was pushed two full lanes to the left into the median barrier and the defendant’s tractor was steered a full lane to the left. The motion of both trucks in this particular simulation was greater than either driver testified. Even so, the impact severity predicted by the most aggressive steer simulation was very minor In this case, I did not simply look at photographs of the damage to the tractor trailers and estimate the crash severity. I conducted a rigorous analysis involving dozens of computer simulations. Therefore, my accident reconstruction in this case is not only scientifically valid, it has a level of reliability that greatly exceeds standard methods used outside of litigation. Additionally, relying on the medical diagnoses of the plaintiff’s treating physicians and using a biomechanical approach to injury causation analysis my primary opinion in this case is that the collision was so minor that the crash forces were within the realm of everyday experience, and therefore unlikely to cause injury. Lastly, I drew a distinction between injuries that result from a single application of mechanical force and chronic degenerative conditions that result from physiological processes or repetitive loading. I cited several dozen biomechanical, clinical, and epidemiological peer-reviewed studies showing that intervetebral disc herniations and rotator cuff tears are relatively common in the population, are rarely caused by trauma, and are strongly associated with genetic and occupational factors. Given the extremely minor nature of the collision, I concluded that the plaintiff’s cervical disc herniations and right rotator cuff tear were more likely degenerative in origin rather than traumatic. All of my opinions are based on a reliable and well-accepted scientific methodology that has been extensively tested and documented in the peer-reviewed literature. The expert has degrees in bio-mechanical engineering and has performed numerous full-scale vehicle-to-vehicle crash tests involving sideswipes. He is a biomedical engineering professor and author or published studies.

1. How severe was the crash? 2. Could the accident have caused the injuries alleged?

Accident reconstruction expert witness for defense opines on dual tractor trailer accident

In this case, a vehicle accident reconstruction expert is enlisted to evaluate allegedly dangerous conditions encountered by the plaintiff in a bike lane. The cyclist typically rode her bike everywhere she went, and on the day in question, she was riding in a bike lane along a busy boulevard. Because the condition of the bike lane was so dangerous, she had to ride about eight feet from the curb. A motorist did not see her and changed lanes to make a turn, driving into the plaintiff’s lane and striking her from behind. As a result of the collision, plaintiff suffered massive head trauma.

She filed claims against the other driver and against the state and county for their alleged failure to maintain the bike lane in a safe condition.

Based upon my inspections and a Scan Station 3D laser survey, as well as the use of some Jvt image processing technology, it was determined that there were significant pavement issues along the curb lane of the boulevard, including sub-base deterioration. In fact, this area had been recommended for re-surfacing three times over the last five years. The poor conditions forced the plaintiff to move to her left in order to maintain control of her bicycle. The height differences all along the curb lane ranged from one half inch to over an inch and one half at some locations. The uneven surface of the roadway created substantial danger to bicyclists riding along the bike route. Riders were placed in the position of attempting to ride over the surface and face losing control of their bicycles and falling, possibly into traffic, or moving further into the lane of travel in order to get to an area that was smooth. The city in this case did not follow any of the sections of the state highway design manual regarding maintenance and repair of bike lanes. Nor did it follow its own bicycle plan. If it had, plaintiff would not have been forced to ride eight feet into the lane of travel and this crash would not have occurred. The alligatored, cracked and torn up condition of the paving of the bikeway that was recommended for resurfacing years before the date of the incident created a hazard to the bicycling public. The surface was not safe for bicyclists to ride over as it would cause bicyclists to lose control. At the very least, there should have been warnings of the dangerous condition. The expert is a traffic and roadway design engineer who is an accident reconstructionist.

1.) Was the bike lane in a dangerous condition? 2.) Were any regulations violated?

Accident Reconstructionist Opines on Bicyclist Forced Into Street by Damaged Bike Lane

Kristin Casler

Case: Sandra and Fred Seamans v. Andrew B. Tremontana, et al., No. 3:13–0698, U.S. District Court, Middle District of Pennsylvania; Sept. 3, 2014 Background: This case involves an accident between Sandra and Fred Seamans and Andrew Tremontana. It occurred on Interstate 81 as the Seamanses were merging onto the highway. A box truck in front


Sandra and Fred Seamans v. Andrew B. Tremontana, et al., No. 3:13–0698, U.S. District Court, Middle District of Pennsylvania; Sept. 3, 2014

This case involves an accident between Sandra and Fred Seamans and Andrew Tremontana. It occurred on Interstate 81 as the Seamanses were merging onto the highway. A box truck in front of Tremontana swerved to avoid hitting the Seamanses’ car. Tremontana was unable to avoid them and rear-ended them, causing their car to spin out. Consequently, the accident left both plaintiffs with various injuries. At issue is whether Tremontana was driving negligently and caused the accident.

The defendants sought to exclude proposed testimony of accident reconstructionist expert Frank Costanzo. They used the grounds that his testimony fails to meet the Daubert standard and usurps the role of the jury.

Costanzo concluded that Tremontana was driving too close to the box truck in front of him, was unable to stop given his 65 mph speed and the spacing, had sufficient time to change lanes prior to the accident, and would have had a clear line of sight had he not been too close to the box truck in front of him or had changed lanes. Thus, he based these conclusions on his inspection of the scene of the crash, the depositions of the plaintiffs and Tremontana, the police reports, the photographs of the cars, his observations of the location of the accident, and several calculations taking into account speed and road conditions.

Admissibility of Accident Reconstructionist Expert:

In a memorandum opinion, Judge Malachy E. Manion of the U.S. District Court for the Western District of Pennsylvania said the essential question regarding Costanzo’s admissibility is whether his testimony is wholly based on knowledge and common sense findings that could just as easily be made by the jury without his testimony.

“The average juror will not know how long it takes a vehicle to stop on a dry highway traveling at 65 miles per hour given that it requires special calculations that take into account speed, road conditions, and other factors,” the judge said. “The defendants do not challenge the basis of this equation or his findings with regard to stopping distance. As such, that testimony is admissible.”

Further, the accident reconstructionist’s opinion that Tremontana could have changed lanes in .17 seconds is relevant to rebut the “sudden emergency” claim given by Tremontana, the judge said.

Lastly, the judge rejected the defendants’ contention that the accident reconstructionist’s opinion embraces the ultimate issue and usurps the role of the jury.

“Here, the expert opines that Mr. Tremontana’s failure to maintain a safe distance between his car and the box truck in front of him and his failure to change lanes to clear his line of sight caused the accident,” the judge said. “Given the above discussion, his opinion on this issue is admissible in so far as it draws a factual conclusion about the factors that caused the accident. He does not draw any legal conclusions or give an opinion directly finding that Mr. Tremontana was negligent. As such, his expert opinion is fully admissible.”

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