Foreword:
Currently, in Washington State, motorcycles make up 4% of the registered vehicles. That still accounts for more than 250,000 vehicles. Yet, the Washington State Department of Transportation and Department of Licensing seem to either totally misunderstand the differences between a motorcycle and an automobile, or simply choose to ignore those differences. As we move closer to the date for reaching Washington State’s “Target Zero”, it is becoming more evident to those who see and understand the differences that strategies to reduce fatalities in automobiles simply cannot be as successful with motorcycles. There are actually very few ways that the two are similar. Until that is realized, and transportation policy ceases seeing motorcycles only as a safety concern, the fatality rate will continue to, in the words of the Washington Traffic Safety Commision, remain “fairly flat”. Which means that the current strategies for automobiles are not as effective with motorcycles.
One of the key problems is that transportation policy planners are currently virtually ignoring motorcycles and other powered two-wheelers. Motorcycles are not currently being integrated into and are underutilized as a part of a comprehensive transportation policy. The evidence of this is quite easy to observe. Take for example the May 2016 WSDOT report Two-Lane Rural Highways Safety Performance Functions. In the 406 pages of the report; pedestrians as mentioned 35 times, bicyclists are mentioned 33 times, and motorcycles aren’t even mentioned at all. Similar disproportionate differences occur in WSDOT’s June 2016 report Urban and Suburban Arterial Safety Performance Functions: Final Report. Possibly more telling of the institutionalized mindset regarding motorcycles is found in the March 2011 WSDOT report Performance Analysis of Centerline Rumble Strips in Washington State.
In that report, it states that “In looking at contributing circumstances for the 35 motorcycle collisions in the dataset, it is clear that CLRS are not an effective countermeasure for this class of vehicle.” The report does not state why centerline rumble strips are not an effective countermeasure, except that there were no reports of sleeping or fatigued motorcyclists associated with the 35 collisions. However, the report does state that the percentage of fatal motorcycle collisions increased by 23%, from 30% to 53%, after installation of centerline rumble strips. The authors of the report state on page 38 that because the motorcycle dataset was “skewing portions of the CLRS analysis”, all the motorcycle collisions were excluded. The authors were so narrowly focused on the effect of centerline rumble strips on fatigued or sleeping drivers that they could not understand the probable reasons for the increase in fatal motorcycle crashes after installation of the rumble strips. Even though they briefly describe the conditions under which most of the crashes occur, their narrow focus and unfamiliarity with even the basic handling characteristics of motorcycles led them to simply “exempt” all motorcycle collisions so that they were no longer “skewing” the data. Anyone who has even the most rudimentary understanding of how a motorcycle travels through a turn can quickly see the relationship between rumble strips and 85% of the motorcycle collisions. These collisions all had one thing in common; flat, unbanked curves. Of the collisions on these curves, 86% were “lane departures to the outside of the curve”.
A motorcycle maneuvers through a curve by leaning. While the body of a car may “lean” somewhat on the suspension, for all intents and purposes, the tires are still flat on the roadway. Motorcycles turn by actually leaning onto the curved sides of their tires. While on the road, a car has approximately 144 square inches of contact with the road surface. A motorcycle on the same road has approximately 16 square inches of contact with the road surface. Now add the fact that in the curve, the motorcycle is no longer in the vertical plane with the roadway, but is off center at an angle equal to the amount of lean needed to maneuver through the curve. Factor in the destabilizing oscillations of the rumble strip on a vehicle with an already offset center of gravity and the reduction of road surface contact below the already small 16 square inches as traction is lost due to the rumble strip. If the destabilizing effects of the rumble strip, decrease in both traction and contact surface, added to lean angle lead to the bike going down in the curve, centrifugal force will send the now sliding motorcycle across the oncoming lane resulting in “lane departures to the outside of the curve”. Just as 86% of the motorcycle collisions on curves were reported.
This combination of disregard and misunderstanding of motorcycles and how they interact with the roadway as opposed to automobiles has led to inefficient transportation policies and planning. It is the hope of this paper to show that motorcycles and other powered two-wheelers can be an effective mode of personal transport that can, in conjunction with other modes of transportation, can be used to; ease traffic congestion during commute times, reduce parking space issues in urban and suburban curbsides, as a fully functioning mode of transportation.
That is not to say that by simply promoting the use of motorcycles all these things will come to pass, but with the promotion of certain strategies and options, the entire transportation system can experience the benefits. As has been shown in other parts of the world, such as the United Kingdom.
Objectives and Actions
1. Safety Statistics
Safety statistics are a key factor in demonstrating whether a process or a proposal such as this is functioning properly. One must acknowledge the negative statistics, but also highlight progress made and focus on possible solutions. Not merely stating the percentage of increase or decrease of fatalities for example. Transportation planners need to look beyond the basic statistics and look to gain a greater understanding of transportation safety issues which should bring greater recognition of what sort of intervention might be effective and when. With an eye towards including long-term trends, since most transportation plans are scheduled out over periods of decades.
The statistics themselves may require better clarification. This would better provide beneficial data to transportation planners. For example; simply stating whether a motorcycle fatality was wearing a helmet or not can be very misleading. According to the National Highway Traffic Safety Administration (NHTSA); 64% of fatalities to unhelmeted motorcyclists are due to injury to parts of the body other than the head, while 81% of fatalities to helmeted motorcyclists are due to injury to parts of the body other than the head. Thus reporting that a motorcyclist died while not wearing a helmet can be somewhat misleading and inflammatory. If the fatality was due, say, to internal organ damage in the torso caused by trauma, whether or not a helmet was worn is unlikely to have had any effect on the final outcome. Also, combining the statistics for “killed” and “seriously injured” can lead to an over estimation of the seriousness of the injuries.
2. Government Recognition
It will be shown that motorcycling has its place alongside that of bicycling, walking, and public transit in the preferred transportation paradigm. Doing so will promote the use of motorcycles in conjunction with bicycling and walking. For those who are less likely to travel to light rail stations for the commute to work or school because the distance to walk is too great, or they are physically unable to pedal a bicycle that distance; motorcycles provide an excellent option while also taking up less room in light rail station parking areas. Also, motorcycles in an urban center will consume much less parking space. Allowing more people to park which should help reduce their stress as has been shown is an issue in the INRIX impact of Parking Pain study.
By the recognition of motorcycles as a fully integrated mode of transportation by transportation planners, it will help raise public awareness Which should aid in reducing the current vulnerability of motorcyclists on the highways. With greater awareness of the differences between automobiles and motorcycles, and their significantly different capabilities and deficiencies, transportation policies can be better focused to aid in increasing safety benefits for all transportation modes.
Conclusions and Discussion
Not recognizing and dealing with the different needs and capabilities of motorcycles on the public roadways may actually have the unintended effect of preventing the reduction of motorcycle fatalities simply due to transportation policies that provide infrastructure that is perfectly safe for an automobile, yet could be a fatal factor in; motorcycle stability, control, and safety.
References:
Target Zero http://www.targetzero.com/
Two-Lane Rural Highways Safety Performance Functions 2016 Shankar, et al. WSDOT https://www.wsdot.wa.gov/research/reports/fullreports/856.1.pdf
Urban and Suburban Arterial Safety Performance Functions: Final Report 2016 Shankar, et al. WSDOT
NHTSA DOT HS 810 856 Traffic Safety Facts, Oct. 2007 Bodily Injury Locations in Fatally Injured Motorcycle Riders pg 2 https://permanent.access.gpo.gov/websites/crashstats.nhtsa.dot.gov/pdf/lps96244.pdf
INRIX Impact of Parking Pain study Cookson, Pishue 2017 http://www2.inrix.com/research-parking-2017
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