SUV Rollover Testing – Rollover Stability Formula

Why does a SUV Rollover?

Rollovers accounted for more than 10,000 fatalities in the USA in 1999. That’s more than side and rear crashes combined. SUVs have the highest number of rollovers per 100 crashes of any other class of vehicles. More than 90 percent of rollovers occur after a vehicle runs off the road and strikes a curb, soft shoulder,  grass, pavement edge, mud, guardrail, or other object that “trips” it, but also shockingly rollovers can happen on a flat roadway as well.  “It’s the fastest growing form of fatalities in motor vehicles today,” says Clarence Ditlow, of the Center for Auto Safety. “And it’s because we have sport utility vehicles that handle differently and we need a real world test that distinguishes how they do in the real world.”

During a normal vehicular accident, vehicles are either rapidly slowed down by hitting an object or another vehicle or sent into in a different direction than they were originally heading. In these accidents the vehicle will slid, skid, spin crunch and even tip, but normally the vehicle does not roll over, unless it has been tripped or the design allows it to rollover due to it being top- heavy. However, if a vehicle has a high center of gravity and is redirected (as when a driver steers in one direction and then has to quickly crank the wheel in the opposite direction) the vehicle can topple and roll.

“The public needs the numbers because more people are being killed, we’re getting more vehicles out there on the road with higher rollover characteristics, and we don’t know which are the good performers and which are the bad performers,” says Ditlow.

All vehicles can roll over if the right conditions are present, such as a loss of control and sliding into a curb, ditch or other object and tripping into a rollover event. However, SUV’s can and do roll over as a result of hard steering on flat, dry pavement, with no tripping device introduced.

SUV Rollover Testing – Center of Gravity Formula

From an engineering point of view, a vehicle’s stability is measured by the formula:

In this rollover / stability formula, T is the ‘track width’ (center of the right front tire to the center of the left front tire) and h is the vehicle’s center of gravity. When this number is 1.2 or greater, the vehicle is unlikely to roll. However, the further the ratio dips below 1.2, the greater the likelihood of roll over.

Rollover occurs because of the absence of a lower center of gravity and a wider track width, which allows automobiles to skid, spin and recover. In a normal evasive maneuver that passenger car drivers safety complete every day, rapidly corrective action (also called over-steering by police officers) causes SUVs to trip and roll. Rollovers occur with all sports utility vehicles but the condition seems is to be worse with the earlier Japanese vehicles. As the ratio approaches 1.0 the tendency for the vehicle to roll is increased. A ratio above 1.2 is considered safer.

The T/2H ratio for one Japanese SUV is approximately 1.05, when computed by the manufacturer with 80% gas, one driver, and no cargo. It is fair to assume that the test driver is 150# or less.  Obviously the vehicle is designed to seat more than one and with all seats filled the T/2H ration is very close to 1.0. Add a full tank of gas and some cargo, in back, plus a roof top carrier and the likelihood of a roll at freeway speeds is assured when a driver makes an abrupt corrective move.

All current SUVs contain a rollover warning, but the warning provided do not mention that every bit of weight added to the passenger compartment, roof racks, and excessive passenger baggage increases the likelihood of a roll.

Basic Reasons for SUV Rollovers & Injuries:

  • Advertised to Carry Too Much Weight
  • SUV’s High Center of Gravity / Narrow Track width a Dangerous Combination
  • SUV Absence of Roll Protection, Roll Bar or Roll Cage
  • Faulty Seat belt protection in many SUVs
  • Ejections in  SUV Rollovers Due to bad door latches and lack of window glazing
  • Seat Back Failures that allow occupants to come out of their seatbelts
  • Lack of Rollover Warnings

SUV Rollover & Roof Crush Defects Lawsuit Evaluation

If you or a member of your family has been involved in a SUV rollover accident, van rollover, truck rollover with a severe roof crush, roof pillar collapse failure or any other serious accident or failure and you have questions about whether the vehicle or roof design may caused or contributed to the accident or injuries, then call us now. Mr. Willis is a Board Certified Personal Injury Attorney with over 20 years of product liability and Rollover litigation experience. Call the Willis Law Firm at 1-800-883-9858 for a Free & Confidential Consultation or Click Here

PLEASE NOTE: The statements and information provided on this web site are for the informational purposes only. This law firm is not affiliated in any way with any trademark owner. The use of any trademarks on this site is for product identification and information purposes only. This webpage is provided to you to assist in SUV Rollover accidents, passenger van rollovers, 15 passenger van rollover accidents, recalls, truck accidents & rollovers, tire tread defects, tire separations, roof crush and roof pillar collapse, seat belt failures, fuel fed fires and other related rollover accident issues, including rollover injuries and deaths. This site is not intended to provide legal advice to the reader and NO attorney-client relationship shall be deemed to arise from the receipt this page and/or its associated pages or any oral or e-mail communication to or from with the Willis Law Firm. There will be NO lawsuits filed, claims made, letters or phone calls made for a prospective client, until that person is represented by the firm. An attorney client relationship only arises after the attorney and client have signed a written attorney client contract.

Mr. Willis is licensed attorney in New York and Texas.  He is a Board Certified in Personal Injury Trial Lawyer, certified by the Texas Board of Legal Specialization. Read more about Board Certification. Principle office is Houston, Texas.

Mr. Willis has represented clients in personal injury, auto accident, SUV  rollover, van & truck rollovers and other product liability and negligence cases from across the United States, including clients from Alabama, Arkansas, Arizona, California, Colorado, Connecticut, Florida, Georgia, Idaho, Illinois, Indiana, Kansas, Kentucky, Louisiana, Maryland, Michigan, Minnesota, Missouri, Montana, North Carolina, Nebraska, New Jersey, New Mexico, Nevada, New York, Ohio, Oklahoma, Oregon, Pennsylvania, South Carolina, South Dakota, Tennessee, Texas, Utah, Virginia, Vermont, Washington, Wisconsin & West Virginia.

Further, any statement or reference to past personal injury, products liability or SUV rollover lawsuits, settlements or verdicts should NOT be relied upon in one’s own case or in your decision on which law firm to hire. All clients’ cases, facts, injuries, damages, venues and lawsuits are different and there is NO way to predict the outcome of a particular case, verdict of a jury or judge or the strength of a case before a judge, jury or the appellate court system. The client is responsible for all of their own medical expenses. All cases are handled on a contingent fee basis. NO attorney’s fees or case costs charged to client, unless a recovery is made for the client. Often in very serious and catastrophic injury and death cases Mr. Willis may associate with another products liability attorney as co-counsel and in other matters, the case may be referred. In cases where a legal matter is referred, Mr. Willis will continue to maintain joint responsibility with the handling attorney or lead counsel and actively monitor the progress and development of the case.  Due to his 33+ years of experience in personal injury and products liability cases, Mr. Willis will often continue to assist in working with the hired experts and engineers and in research of the defective product or other related legal matters in the case.