Harry Hurt, the author of the only comprehensive investigation ever made into the factors that effect motorcycle safety, died November 29th at Pomona Valley Hospital east of Los Angeles. Susan Carpenter of the Los Angeles Times has reported that he died from a heart attack that was the result of back surgery on November 22nd.
Hurt’s first motorcycle was a Cushman scooter he tore apart and rebuilt as a kid in Big Springs, Texas. He graduated from Texas A&M in 1950 and served as a Navy pilot in Korea. After his discharge, he rode from Texas to California on a 1947, EL 61 Knucklehead. He earned a Master’s degree in Engineering at the University of Southern California and joined the faculty there. His advisor and mentor was Charles “Red” Lombard who invented and patented the energy-absorbing motorcycle helmet in 1953.
Hurt was working at the USC Traffic Safety Center in 1975 when the National Highway Traffic Safety Administration asked him to do a scientific study of motorcycle injuries and crashes. During 1976 and 1977 Hurt and two other USC researches named David Thom and James Ouellet conducted on-scene investigations of 900 motorcycle accidents in Los Angeles County. The researchers photographed, examined and measured each accident site; interviewed the survivors; interviewed 2,310 passing motorcyclists; and studied 3,600 police reports of other accidents reported at those sites.
The Hurt Report
In 1981 Hurt published a book titled, Volume I: Technical Report, Motorcycle Accident Cause Factors and Identification of Countermeasures, January, 1981 – Final Report. Nobody wanted to have to say all that, however, so for the last 38 years it has simply been called The Hurt Report.
What Hurt concluded never surprised motorcyclists and his long held prejudice in favor of helmet laws still infuriated some bikers until his dying day.
In 1981, Hurt assumed that his would be only the first of many studies into motorcycle safety. As it turned out The Hurt Report was the one and only. And, his results were skewed by the time and place, Los Angeles in the late seventies, where his study was conducted. So, for example, a similar study conducted in some other place would indicate far more accidents caused by collisions with deer, wild turkeys and feral pigs. And, in 1977 the phrase “road rage” had not yet been coined.
The official summary of Hurt’s findings supplied by the National Technical Information Service includes the following conclusions.
Don’t Be Stupid
Approximately three-fourths of motorcycle accidents involved collision with another vehicle, which was most often a passenger automobile.
Approximately one-fourth of motorcycle accidents were single vehicle accidents involving the motorcycle colliding with the roadway or some fixed object in the environment.
Vehicle failure accounted for less than three percent of motorcycle accidents, and most of those are single vehicle accidents where control was lost due to a puncture flat.
In single vehicle accidents, motorcycle rider error was present as the accident precipitating factor in about two-thirds of the cases, with the typical error being a slide-out and fall due to over-braking or running wide on a curve due to excess speed or under-cornering.
Roadway defects (pavement ridges, potholes, etc.) were the accident cause in two percent of the accidents; animal involvement was one percent of the accidents.
Remember You Are Invisible
In multiple vehicle accidents, the driver of the other vehicle violated the motorcycle right-of-way and caused the accident two-thirds of the time.
The failure of motorists to detect and recognize motorcycles in traffic is the predominating cause of motorcycle accidents. The driver of the other vehicle involved in collision with the motorcycle did not see the motorcycle before the collision, or did not see the motorcycle until too late to avoid the collision.
Deliberate hostile action by a motorist against a motorcycle rider is a rare accident cause. The most frequent accident configuration is the motorcycle proceeding straight then the automobile makes a left turn in front of the oncoming motorcycle.
Intersections are the most likely place for the motorcycle accident, with the other vehicle violating the motorcycle right-of-way, and often violating traffic controls.
Loud Pipes Save Lives
Weather is not a factor in ninety-eight percent of motorcycle accidents.
Most motorcycle accidents involve a short trip associated with shopping, errands, friends, entertainment or recreation, and the accident is likely to happen in a very short time close to the trip origin.
The view of the motorcycle or the other vehicle involved in the accident is limited by glare or obstructed by other vehicles in almost half of the multiple vehicle accidents.
Conspicuity of the motorcycle is a critical factor in the multiple vehicle accidents, and accident involvement is significantly reduced by the use of motorcycle headlamps (on in daylight) and the wearing of high visibility yellow, orange or bright red jackets.
Get The Bike Up, Shut Off The Gas
Fuel system leaks and spills were present in 62% of the motorcycle accidents in the post-crash phase. This represents an undue hazard for fire.
The median pre-crash speed was 29.8 mph, and the median crash speed was 21.5 mph, and the one-in-a-thousand crash speed is approximately 86 mph.
The typical motorcycle pre-crash lines-of-sight to the traffic hazard portray no contribution of the limits of peripheral vision; more than three-fourths of all accident hazards are within forty-five degrees of either side of straight ahead.
Conspicuity of the motorcycle is most critical for the frontal surfaces of the motorcycle and rider.
Vehicle defects related to accident causation are rare and likely to be due to deficient or defective maintenance.
Motorcycle riders between the ages of 16 and 24 are significantly overrepresented in accidents; motorcycle riders between the ages of 30 and 50 are significantly underrepresented. Although the majority of the accident-involved motorcycle riders are male (ninety-six percent,) the female motorcycles riders are significantly overrepresented in the accident data.
Craftsmen, laborers, and students comprise most of the accident-involved motorcycle riders. Professionals, sales workers, and craftsmen are underrepresented and laborers, students and unemployed are overrepresented in the accidents.
Motorcycle riders with previous recent traffic citations and accidents are overrepresented in the accident data.
The motorcycle riders involved in accidents are essentially without training; ninety-two percent were self-taught or learned from family or friends. Motorcycle rider training experience reduces accident involvement and is related to reduced injuries in the event of accidents.
More than half of the accident-involved motorcycle riders had less than five months experience on the accident motorcycle, although the total street riding experience was almost three years. Motorcycle riders with dirt bike experience are significantly underrepresented in the accident data.
Learn To Swerve And Countersteer
Lack of attention to the driving task is a common factor for the motorcyclist in an accident.
Almost half of the fatal accidents show alcohol involvement.
Motorcycle riders in these accidents showed significant collision avoidance problems. Most riders would over-brake and skid the rear wheel, and under-brake the front wheel greatly reducing collision avoidance deceleration. The ability to countersteer and swerve was essentially absent.
The typical motorcycle accident allows the motorcyclist just less than 2 seconds to complete all collision avoidance action.
Passenger-carrying motorcycles are not overrepresented in the accident area.
Beware The Young And Old
The driver of the other vehicles involved in collision with the motorcycle are not distinguished from other accident populations except that the ages of 20 to 29, and beyond 65 are overrepresented. Also, these drivers are generally unfamiliar with motorcycles.
Large displacement motorcycles are underrepresented in accidents but they are associated with higher injury severity when involved in accidents.
Any effect of motorcycle color on accident involvement is not determinable from these data, but is expected to be insignificant because the frontal surfaces are most often presented to the other vehicle involved in the collision.
Motorcycles equipped with fairings and windshields are underrepresented in accidents, most likely because of the contribution to conspicuity and the association with more experienced and trained riders.
Motorcycle riders in these accidents were significantly without motorcycle license, without any license, or with license revoked.
Watch Your Trail And Rake
Motorcycle modifications such as those associated with the semi-chopper or cafe racer are definitely overrepresented in accidents.
The likelihood of injury is extremely high in these motorcycle accidents. Ninety-eight percent of the multiple vehicle collisions and ninety-six percent of the single vehicle accidents resulted in some kind of injury to the motorcycle rider. Forty-five percent resulted in more than a minor injury.
Half of the injuries to the somatic regions were to the ankle-foot, lower leg, knee, and thigh-upper leg.
Crash bars are not an effective injury countermeasure; the reduction of injury to the ankle-foot is balanced by increase of injury to the thigh-upper leg, knee, and lower leg.
The use of heavy boots, jacket, gloves, etc., is effective in preventing or reducing abrasions and lacerations, which are frequent but rarely severe injuries.
Groin injuries were sustained by the motorcyclist in at least 13% of the accidents, which typified by multiple vehicle collision in frontal impact at higher than average speed.
Injury severity increases with speed, alcohol involvement and motorcycle size.
Seventy-three percent of the accident-involved motorcycle riders used no eye protection, and it is likely that the wind on the unprotected eyes contributed in impairment of vision which delayed hazard detection.
Motorcyclist Of The Decade
In 1990, Motorcyclist magazine named Hurt “Motorcyclist of the Decade.”
Hurt is survived by his widow, Joan; his sons Harry and John; his daughters Julie, Vivien and Vera; and ten grandchildren.
Harry Hurt was 81. He tried to help.
Requiescat In Pace