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7 Chapter 2 Analysis of Real World Crash Information An investigation of cases in the National Automotive Sampling System Crashworthiness Data Systems (NASS/CDS) [13] and the Fatal Accident Reporting System (FARS) [28] databases unearthed many accidents involving vehicles and roadside hardware systems. It was found that the different classes of vehicles had different compatibility issues with roadside hardware systems. These issues were investigated using two different approaches. The first approach used statistical analysis to find correlations between vehicle characteristics and roadside hardware compatibility. The second approach examined individual accident cases to gain further insight into compatibility issues. 2.1 Statistical Analysis A detailed investigation of NASS/CDS and FARS databases was conducted to understand the impact performance of vehicle body types during crashes with roadside objects. The vehicle body types surveyed included different sizes of cars, SUVs, pickup trucks and vans. Roadside hardware objects were categorized as guardrails, concrete median barriers and small to midsized poles and posts. New vehicle classifications were derived based on vehicle mass, wheelbase and body style. This classification was adopted in this study due to limitations found in the classification schemes currently used in NASS and FARS databases. The absence of a midsize SUV category and outdated mass cutoffs for the small car category prompted this reclassification. These new vehicle classes are listed in Table 2.1. Cars Classification Compact Weight < 2000 lb. OR Length < 165 in. OR (Weight < 2900 lb. AND Length < 183 in.) Midsized If vehicle is not compact AND (Weight ⤠3400 lb. AND Length ⤠200 in.) Large Weight > 3400 lb. OR Length > 200 in. SUVs Compact Weight < 3500 lb.
8 Midsized 3500 lb. ⤠Weight ⤠4850 lb. AND Length < 190 in. AND Height < 75 in. Large Length ⥠190 in. OR Weight > 4850 lb. OR Height > 75 in. Pickup Trucks Compact Weight < 3500 lb. AND Height < 70 in. Large Weight ⥠3500 lb. OR Height ⥠70 in. Vans Midsized Height ⤠70 in. OR (Height < 75 in. AND Weight < 4000 lb.) Large Height ⥠70 in. OR Weight > 4000 lb. Table 2.01 Reclassification criteria for new vehicle categories Over 90% of all passenger vehicles listed in the 2000 registration database were classified using this new scheme. Low volume models, pre-1980 models, and vehicles with missing dimensional information could not be classified. All statistical analysis includes only those vehicles where the key dimensional attributes are known. Figure 2.1 shows crash mode distribution by body type for these vehicle classes listed above. The figure includes frontal, near side, far side, rear and rollover crashes. Frontal crashes are defined as impacts where the Principal Direction of Force (PDOF) is 10 o'clock through 2 o'clock and the General Area of Damage (GAD) is "front." Nearside crashes occur when the GAD is side and the occupant in question is seated on this side of the vehicle. Far side crashes are side impacts where the occupant is seated on the non-struck side of the vehicle. Rear crashes involve a PDOF of 5 through 7 o'clock and a "rear" GAD. A crash is classified as a rollover if a vehicle undergoes at least one quarter-turn. In addition to the percent of total, included in the figure is the percent involvement of frontal and rollover crashes for each class. It can be observed from the figure that compact and midsize SUV's are nearly six times more likely to be involved in rollover events than midsize cars.
9 Figure 2.01 Crash involvement of passenger vehicles by impact mode (1998-2000 NASS/CDS) Fatality rates for each vehicle class were also investigated. These rates, shown in Table 2.3, are presented in deaths per million vehicles registered. The four columns in the table display: fatality rates for all occurring crashes, crashes where guardrail impact was the most harmful event, crashes where concrete barriers were the most harmful event and crashes where posts and poles were the most harmful event. Each set of data has been ranked by fatality rate. The highest rates were placed at the top and the lowest at the bottom. A similar analysis was performed with rollover crashes excluded from the data, these results are listed in Table 2.4. In the table of all crashes (including rollover), fatality rates for compact cars are higher than fatality rates for other vehicle classes. However midsize and large SUVs have the highest fatality rates during Guardrail and Concrete Median Barrier impacts. Table 2.4, where rollover events are not considered, shows that fatality rates for SUV impacts with longitudinal barriers drop below the fatality rates of small and midsize cars. During this analysis, adjustment for vehicle occupancy was considered. Table 2.2 shows the average number of vehicle occupants per vehicle class. Figure 2.2 shows these values in terms of occupant count for each vehicle body type. These occupancy values are normalized as a percent of the total number of crashes for each vehicle category. Further normalization by crash involvement reveals that SUV's are involved in slightly more crashes per vehicle registered than pickup trucks so that the fatality rates may be influenced by driver behavior in addition to the crash performance of each vehicle class. This trend is recognized however no adjustment for this trend has been made during this analysis.
10 Body Type Ave. Occupants Per Vehicle Percent Difference vs. Passenger Cars Cars 1.46 Baseline Small SUV's 1.49 1.9% Large SUV's 1.64 11.7% Small Pickups 1.28 -12.6% Large Pickups 1.41 -3.6% Minivans 1.83 25.0% Table 2.02 Occupancy rates for each vehicle class relative to passenger car occupancy Figure 2.02: Occupancy counts normalized by total crash count per vehicle class Another observation is that compact cars have the highest fatality rates during impacts with poles and posts.
11 Rollover Cases Included All Crashes Guardrails Concrete Barriers Posts/Poles Comp Car 192.2 Mid SUV 8.6 Lrg SUV 2.3 Comp Car 14.3 Comp Trk 189.4 Lrg SUV 7.5 Comp SUV 1.9 Mid Car 13.4 Lrg SUV 189.1 Comp Car 5.8 Mid SUV 1.8 Comp Trk 12.9 Mid SUV 176.6 Mid Car 5.7 Comp Car 1.4 Lrg SUV 11.9 Mid Car 168.5 Comp SUV 5.6 Mid Car 1.2 Lrg Car 10.1 Comp SUV 156.9 Comp Trk 4.9 Lrg Van 0.9 Mid SUV 9.9 Lrg Car 133.6 Lrg Trk 4.6 Mid Van 0.9 Comp SUV 9.6 Mid Van 117.1 Lrg Car 4.3 Lrg Car 0.9 Lrg Trk 7.2 Lrg Trk 111.3 Mid Van 4.2 Comp Trk 0.9 Lrg Van 5.7 Lrg Van 87.5 Lrg Van 3.9 Lrg Trk 0.6 Mid Van 4.8 Table 2.03 Fatality rates for each vehicle class ranked from highest to lowest Rollover Cases Excluded All Crashes Guardrails Concrete Barriers Posts/Poles Comp Car 147.6 Mid Car 3.4 Comp Car 0.9 Comp Car 10.5 Mid Car 130.4 Comp Car 3.3 Mid Car 0.8 Mid Car 9.7 Comp Trk 112.7 Lrg Car 2.8 Lrg SUV 0.7 Lrg Car 7.8 Lrg Car 110.9 Mid SUV 2.5 Lrg Car 0.7 Comp Trk 7.8 Lrg SUV 78.9 Comp SUV 2.2 Mid Van 0.5 Lrg SUV 5.5 Mid Van 74.1 Comp Trk 2.0 Comp SUV 0.4 Lrg Trk 3.9 Lrg Trk 62.3 Lrg Trk 1.9 Lrg Van 0.4 Mid SUV 3.7 Mid SUV 59.5 Mid Van 1.9 Comp Trk 0.3 Lrg Van 3.6 Comp SUV 58.8 Lrg SUV 1.4 Mid SUV 0.3 Comp SUV 3.5 Lrg Van 48.9 Lrg Van 1.4 Lrg Trk 0.3 Mid Van 2.9 Table 2.04 Fatality rates excluding rollover-involved fatalities for each vehicle class ranked from highest to lowest The NASS/CDS database was also used to assess fatality counts for impacts where the most harmful event was contact with a roadside hardware object. Fatality trends in impacts involving these objects were found per vehicle class based on the population of those vehicles on the road from 1990-2000. The analysis did not show significant differences in crash performance as vehicle design changed over this ten year period. It should be noted the frequency of roadside device installations was not included in the analysis therefore exposure was not well accounted for.
12 2.2 Single Vehicle Crash Case Reviews In order to examine the vehicle to guardrail interaction more closely and identify compatibility issues, a thorough investigation of individual crash cases from the NASS/CDS database was performed. A web- based query tool was developed to facilitate access to complete NASS/CDS case information. The tool was used to query the NASS/CDS database with a user defined set of crash attributes. Once the cases were chosen, the tool allowed the individual cases to be reviewed in a simple and easy to read format. In these summaries, all data points recorded by NASS/CDS investigators were available, including the scene diagrams and post-crash photographs. Key variables from the NASS/CDS database have been selected for this study and displayed for each individual case. These variables gave a concise overview of the following accident attributes: 1. Crash Severity 2. Pre-Crash Environment 3. Vehicle Factors 4. Pre-Crash Driver Data 5. Driver Factors 6. Severe Injuries Sustained Per Occupant This format was chosen to understand crash causation, vehicle behavior and injuries for individual roadside hardware crashes. Due to the limited amount of information concerning the roadside hardware systems in the NASS/CDS database, the crash photos were carefully examined to determine the type of guardrail involved in the collision. Upon completion of review for each case, the four photographs that best represent the case were chosen. The summary sheets were created, which include these photographs, the relevant case information, the scene diagram and the case summary to highlight the nature of the crash event. Note: In some cases, certain data points could not obtained by NASS crash investigators and are therefore unavailable for this analysis. These data points, including some deltaV values and impact speeds, are alternatively coded as <5 km/h or 998 to indicate unknowns. This occurs in some cases because current methods used to retrospectively calculate deltaV based on vehicle crush are not valid for underride or override situations seen during some roadside hardware impacts. Similarly, impact speed is
13 difficult to discern if final rest position and impact trajectory is unavailable. The data presented here is based on the best available crash information available within the NASS/CDS database. The case review revealed different levels of vehicle to roadside hardware compatibility. Guardrails performed well when impacted by cars. Very few injuries were found in car to guardrail collisions involving a belted occupant. Un-belted occupants suffered more injuries than belted occupants, however many of these injuries were caused by partial or full ejection upon impact. Therefore it was hypothesized that the installation of a side curtain airbag would help reduce these injuries. More injuries were found in impacts involving cars and concrete barriers. Side curtain airbags would also help to reduce these injuries. Airbags can also be used to minimize the acceleration during automobile impacts with end terminals, however the timing of the airbag deployment could be critical. Pick-up trucks and SUVs suffered from different types of incompatibilities with roadside hardware systems. The higher CG of these vehicles led to the vaulting of roadside barriers more frequently than cars. In addition, many of the injuries found in impacts between these vehicles and roadside hardware systems were the result of a rollover. In several cases, the hardware itself tripped the vehicle inducing a roll. A second mechanism of roll occurred due to an instability introduced by the collision with a barrier. Even though the barrier redirected the vehicle, this added instability caused the vehicle to roll later in the crash event. The following 13 cases have been selected as examples of typical behavior during passenger vehicle impacts with roadside devices. In all of these cases the roadside device was the first or second most harmful event, and a serious injury (Maximum Abbreviated Injury Severity [MAIS] level 3+) occurred. Additionally, Appendix A contains a further selection of NASS/CDS cases meeting these criteria.
14 Case 1: 1998-75-154 In this case, a driver of a Toyota 4-Runner lost control while attempting a right-hand turn. Once out of control, the vehicle impacted a guardrail, climbed over the rail and subsequently rolled over. The rollover was a climb over initiated event with a tripping force applied to the undercarriage of the vehicle as indicated by the NASS investigator. The vehicle completed 5-quarter turns, and the occupant was ejected and killed. This case is an example of poor interaction between the vehicle and barrier system where the guardrail failed to contain an SUV. Investigation into the scene and vehicle post crash pictures showed that the SUV hit the guardrail at a modest angle; however the SUV vaulted the barrier. It is hypothesized that impact severity (impact speed) may have exceeded the design capacity of this barrier; however, the post impact trajectory, as indicated by the scaled scene diagram, does not suggest excessive impact energy where multiple vehicle rolls occurred over a large distance. Current NCHRP 350 guidelines test these barrier systems at 100 km/h, 80 km/h and 60 km/h. This impact appears to have been at a lower severity than those required by NCHRP 350. Pictures of the scene showed the guardrail to be a W-beam rail with wood posts and wood blockouts. It appears the guardrail was installed down a backslope. The high ground clearance, short overhang and exposed front tires of the 4-Runner led to interaction of the tires and barrier climbing by the vehicle. Additionally, the high CG and low static stability factor of this vehicle raised the risk of subsequent rollover once the vehicle climbed over the barrier system. Important Factors ⢠Height of Treatment Relative to Roadway ⢠Installation Height of Treatment ⢠Distance of Treatment Relative to Roadway ⢠Downward Slope of Roadside before Impact Point ⢠CG Height of Toyota 4-Runner ⢠Average CG Height of Mid-Size SUVs ⢠Average CG Height of Full Size Pickup Trucks ⢠Researcher Determined Impact Angle
15 1 Case 1998-75-154 Summary: V1 WAS TRAVELING WESTBOUND ON A TWO LANE TWO-WAY ROADWAY. V1 HAD JUST NEGOTIATED A SLIGHT RIGHT CURVE IN THE ROADWAY WHEN CONTROL OF THE VEHICLE WAS LOST. THE VEHICLE TRAVELED TO THE LEFT ACROSS THE CENTER LANE LINE, YAWED COUNTER CLOCKWISE ACROSS THE EASTBOUND TRAVEL LANE AND IMPACTED A GUARDRAIL WITH ITS FRONT. THE VEHICLE CONTINUED WESTBOUND, CLIMBING OVER THE GUARDRAIL AND BECAME AIRBORNE. THE VEHICLE HIT THE GROUND, ROTATED SLIGHTLY CLOCKWISE HIT A SMALL TREE AND ROLLED 5 QUARTER TURNS LEADING WITH ITS LEFT SIDE. DURING THE ROLLOVER, THE RIGHT FRONT DOOR OPENED. THE DRIVER WAS EJECTED THROUGH THE WINDSHIELD. THE DRIVER CAME TO REST APPROXIMATELY 13 METERS FROM V1'S FINAL REST. V1 CAME TO REST ON ITS LEFT SIDE FACING NORTHWEST. THE VEHICLE WAS TOWED FROM THE SCENE. THE DRIVER WAS TRANSPORTED AND DIED APPROXIMATELY 5 HOURS AFTER THE ACIDENT. Vehicle Body Type Make Model Year Occ.# Age Occupantâs sex Maximum known occupant ais 1 COMPACT UTILITY Toyota 4-Runner 1997 1 48 MALE 5 = CRITICAL INJURY Figure 2.03: Case 1: Summary
16 Occupant: 1998-75-154-1-1 Rollover Classification Number of Harmful Events 3 Rollover Initiation Type CLIMB-OVER Location of Rollover Initiation ROADSIDE/MEDIAN Rollover Initiation Object OTHER BARRIER Contacted Location on Vehicle where Principal Tripping Force was Applied UNDERCARRIAGE Direction of Initial Roll ROLL LEFT Crash Severity Nr. Quarter Turns 5 QUARTER TURNS Impact Speed < 0.5 KMPH Total, Longitudal, and < 0.5 KMPH < 0.5 KMPH < Lateral delta-V 0.5 KMPH Estimated delta-V with SEVERE 3 Sequence number CDC 0 T Z D O 6 Run off Road Damage (C1-C6) 0 0 0 0 0 0 Crush (L and D) 0 0 Pre-Crash Environment Traffic Flow NOT DIVIDED Number of Travel Lanes TWO Roadway Alignment CURVE RIGHT Roadway Profile UPHILL GRADE Roadway Surface Type ASPHALT Roadway Surface Condition DRY Light Conditions DARK/LIGHTED Atmospheric Conditions NO ADVERSE COND Relation to Intersection NONINTER/NONJUNC Traffic Control Device Police Reported Alcohol ALCOHOL PRESENT Presence Alcohol Test (< 95 indicates 26 BAC 0.xx) Vehicle Factors Make-Model Toyota 4-Runner Year 1997 Class PASSENGER CAR Body Type COMPACT UTILITY Weight 183 NASS Weighting Factor Weighting factor 60.957641664 Pre-Crash Driver Data Accident Type 7 Pre-event Movement NEGOTIATE CURVE Critical Pre-crash Event OFF EDGE-LEFT Attempted Avoidance BRAKE W/O LOCKUP Maneuver Pre-impact Stability LATERAL SKID-CLK Pre-impact Location DEPARTED ROADWAY DRIVER Factors Age 48 Height 178 Weight 77 Gender MALE Restrain NONE USED/AVAIL Airbag Deployment NONDEPLOYED Ejection COMPLETE EJECT Ejection Area WINDSHIELD Entrapment NOT ENTRAPPED Airbag Deployment â 1st Seat NONDEPLOYED Airbag Deployment â Other NOT EQUIP W/ OTH Seat AOPS YES-RES DET Injuries Occupant 1 MAIS 5 = CRITICAL INJURY Seat Position FRONT LEFT SIDE Figure 2.04: Case 1: Crash Information
17 Case 2: 2000-12-4 In this case a Pontiac Grand Prix was traveling on a snowy road when it lost control. A clockwise rotation was induced and the vehicle went off of the road to the right. The vehicle engaged a guardrail end terminal, but due to the direction of the velocity vector only a short portion of the beam was deformed as designed. Buckling downstream of the impact point due to bending loads lead to redirection of the vehicle down the backslope. As the vehicle initiated a rollover down the hill, the driver was severely injured due to multiple contacts inside the vehicle compartment. Initially, the guardrail terminal performed as designed. An examination of the car showed some damage, but there was little barrier penetration into the occupant compartment as seen in other end terminal cases. Due to the compatible heights of the door sill and the lowest point on the end terminal, the stiff vehicle side structure adequately transferred energy to the barrier. An examination of the accident scene showed that the guardrail absorbed some energy and deflected adequately, however the distance between this installation and the backslope may have been too small. Had the terminal been installed slightly upstream, the system may decelerate the vehicle sufficiently before the backslope to avoid the rollover. Similar cases were seen where a guardrail terminal decelerated the vehicle, but the vehicle still subsequently impacted trees, poles and bridge posts with sufficient speed to cause injury. Therefore the installation of a guardrail should ensure that the hazard is protected using a sufficiently long section of guardrail. In doing this, the guardrail terminal will be installed well forward of the protected hazard. Other Similar Cases: 1998-12-18, 1999-73-12, 2000-12-4, 2000-8-190 Important Factors ⢠Location of End-Terminal Relative to Hazard ⢠Length of Deformation of End Terminal ⢠Vehicle Door Sill Height ⢠Average Mid-Size Vehicle door Sill Height ⢠Height of Treatment (bottom edge) ⢠Researcher Determined Impact Angle
18 2 Case 2000-12-4 Summary: V1 WAS HEADED NORTH ON A 3 LANE, SNOWY, ASPHALT ROADWAY AFTER DARK AND WITH LITTLE OR NO ARTIFICIAL LIGHTING. TRAVELING IN LANE 1, V1 LOST CONTROL OF HIS VEHICLE DUE TO WEATHER CONDITIONS AND LEFT THE ROADWAY TO THE RIGHT STRIKING A GUARDRAIL PRIOR TO FINAL REST ON THE LEFT SIDE OF THE VEHICLE OFF ROAD. THE VEHICLE WAS TOWED DUE TO DAMAGE AND THE DRIVER WAS TRANSPORTED TO MEDICAL ATTENTION DUE TO THE SEVERITY OF HIS INJURIES. Vehicle Body Type Make Model Year Occ.# Age Occupantâs sex Maximum known occupant ais 1 2DR SEDAN/HT/CPE Pontiac Grand Prix 1997 1 32 MALE 3 = SERIOUS INJURY Figure 2.05: Case 2: Summary
19 Occupant: 2000-12-4-1-1 Rollover Classification Number of Harmful Events 2 Rollover Initiation Type TRIP-OVER Location of Rollover Initiation ROADSIDE/MEDIAN Rollover Initiation Object OTHER FIXED OBJECT Contacted Location on Vehicle where Principal Tripping Force was Applied WHEELS/TIRES Direction of Initial Roll ROLL LEFT Crash Severity Nr. Quarter Turns 5 QUARTER TURNS Impact Speed < 0.5 KMPH Total, Longitudal, and < 0.5 KMPH < 0.5 KMPH < Lateral delta-V 0.5 KMPH Estimated delta-V with DELTA V CODED 1 Sequence Number CDC 11 L D E W 3 Run off Road Damage (C1-C6) 29 15 13 23 7 4 Crush (L and D) 443 0 Pre-Crash Environment Traffic Flow ONE WAY Number of Travel Lanes THREE Roadway Alignment CURVE RIGHT Roadway Profile LEVEL Roadway Surface Type ASPHALT Roadway Surface Condition SNOW OR SLUSH Light Conditions DARK Atmospheric Conditions SNOW Relation to Intersection NONINTER/NONJUNC Traffic Control Device Police Reported Alcohol ALCOHOL PRESENT Presence Alcohol Test (< 95 indicates 16 BAC 0.xx) Vehicle Factors Make-Model Pontiac Grand Prix Year 1997 Class PASSENGER CAR Body Type 2DR SEADAN/HT/CPE Weight 151 NASS Weighting Factor Weighting factor 46.019742061 Pre-Crash Driver Data Accident Type 2 Pre-event Movement NEGOTIATE CURVE Critical Pre-crash Event POOR ROAD COND Attempted Avoidance NO AVOIDANCE Maneuver Pre-impact Stability LATERAL SKID-CLK Pre-impact Location DEPARTED ROADWAY DRIVER Factors Age 32 Height 180 Weight 86 Gender MALE Restrain LAP AND SHOULDER Airbag Deployment NONDEPLOYED Ejection NO EJECTION Ejection Area NO EJECTION Entrapment NOT ENTRAPPED Airbag Deployment â 1st Seat NONDEPLOYED Airbag Deployment â Other NOT EQUIP W/ OTH Seat AOPS YES-RES DET Injuries Occupant 1 MAIS 3 = SERIOUS INJURY Seat Position FRONT LEFT SIDE AIS Level Region Injured Contacts 3 = SERIOUS INJURY CHEST BELT WEBB/BUCK Figure 2.06: Case 2: Crash Information
20 Case 3: 1999-11-70 This case showed a Ford Escort that impacted a concrete barrier while trying to avoid another car. The occupant in this case suffered severe injuries, although he was belted and did not hit a concrete barrier at a severe angle. This case demonstrates the typical behavior of small and midsize vehicle impacting concrete median barriers. Although the occupant was belted, he sustained head injuries due to steering wheel contact. The contact marks on the barrier indicates that the impact angle was shallow enough to lift and deflect the vehicle downstream so that the PDOF is estimated to be about 11 o'clock. Further, scrapes on the rear of the vehicle indicate that the vehicle yawed/rotated back out toward traffic without a high longitudinal acceleration of the vehicle. For this impact scenario, a more vertical barrier profile may have reduced the longitudinal acceleration of the vehicle, which leads to the head strike. However, a reduction in longitudinal deceleration would result in a higher lateral acceleration force of the vehicle and occupant. Further analysis is necessary to understand if this tradeoff would lead to increased or decreased occupant risk. The contribution of frontal airbag systems (not available here) would also change occupant injury potential for this impact condition. Any new design of concrete median barriers must not only consider interaction with cars, but also trucks and SUVs, which may benefit from increased barrier slopes as well. Important Factors ⢠Barrier Impact Speed ⢠Barrier Profile ⢠Occupant Restraint system and Kinematics ⢠Researcher Determined Impact Angle Other Similar Cases: 1999-12-120,1999-72-71,1999-73-92, 1999-9-7, 2000-73-167, 1999-8-226, 1997-45-198, 1998-12-161
21 3 Case 1999-11-70 Summary: V1 A 1988 FORD ESCORT WAS TRAVELING WESTBOUND IN LANE TWO ON AN EXPRESSWAY. THE EXPRESSWAY IS PHYSICALLY DIVIDED BY A MEDIAN WALL. A NON-CONTACT VEHICLE CAME INTO LANE TWO AND V1 STEERED LEFT TO AVOID THE VEHICLE. V1 LOST CONTROL AND WENT OFF ON THE LEFT SIDE OF THE ROADWAY (ON THE SHOULDER) AND THE FRONT LEFT BUMPER OF HIS VEHICLE CONTACTED THE MEDIAN WALL. V1 WAS TOWED DUE TO VEHICLE DAMAGE. THE DRIVER OF V1 WAS TRANSPORTED AND HOSPITALIZED DUE TO HIS INJURIES HE SUSTAINED FROM THE ACCIDENT. Vehicle Body Type Make Model Year Occ.# Age Occupantâs sex Maximum known occupant ais 1 3DR/2DR HATCHBAK Ford Escort/EXP 1988 1 17 MALE 3 = SERIOUS INJURY Figure 2.07: Case 3: Summary
22 Occupant: 1999-11-70-1-1 Rollover Classification Number of Harmful Events 1 Rollover Initiation Type NO ROLLOVER Location of Rollover Initiation NO ROLLOVER Rollover Initiation Object NO ROLLOVER Contacted Location on Vehicle where Principal Tripping Force was Applied NO ROLLOVER Direction of Initial Roll NO ROLLOVER Crash Severity Nr. Quarter Turns NO ROLLOVER Impact Speed 998 Total, Longitudal, and 30 28 10 Lateral delta-V Estimated delta-V with DELTA V CODED 1 Sequence Number CDC 11 F D E W 2 Run off Road Damage (C1-C6) 45 38 26 16 4 0 Crush (L and D) 140-16 Pre-Crash Environment Traffic Flow DIVIDED WITH BARRIER Number of Travel Lanes THREE Roadway Alignment STRAIGHT Roadway Profile LEVEL Roadway Surface Type ASPHALT Roadway Surface Condition DRY Light Conditions DAY LIGHT Atmospheric Conditions NO ADVERSE COND Relation to Intersection NONINTER/NONJUNC Traffic Control Device Police Reported Alcohol NO ALCOHOL Presence Alcohol Test (< 95 indicates 0 BAC 0.xx) Vehicle Factors Make-Model Ford Escort/EXP Year 1988 Class PASSENGER CAR Body Type 3DR/2DR HATCHBACK Weight 101 NASS Weighting Factor Weighting factor 213.58406145 Pre-Crash Driver Data Accident Type 8 Pre-event Movement GOING STRAIGHT Critical Pre-crash Event SAME DIR-OV LEFT Attempted Avoidance STEERING RIGHT Maneuver Pre-impact Stability LONGITUDINAL SKID Pre-impact Location LEFT TRAVEL LANE DRIVER Factors Age 17 Height 180 Weight 82 Gender MALE Restrain LAP BELT Airbag Deployment NOT EQUIP/AVAIL Ejection NO EJECTION Ejection Area NO EJECTION Entrapment NOT ENTRAPPED Airbag Deployment â 1st Seat NOT EQUIP/AVAIL Airbag Deployment â Other NOT EQUIP W/ OTH Seat AOPS YES-RES DET Injuries Occupant 1 MAIS 3 = SERIOUS INJURY Seat Position FRONT LEFT SIDE AIS Level Region Injured Contacts 3 = SERIOUS INJURY HEAD-SKULL STEERING RIM Figure 2.08: Case 3: Crash Information
23 Case 4: 2000-13-113 In this case, an Oldsmobile Cutlass drifted off of the road and impacted a guardrail without an end terminal head on. The vehicle was severely damaged and the occupant was fatally injured. The magnitude of the vehicle deformation suggested a very large deltaV or a stiff barrier system. Critical information was missing within this case to draw either conclusion. The occupant suffered fatal injuries. It should be noted that the driver was not belted in a non- airbag equipped vehicle. Due to the delayed investigation of this case, it is unclear what the resulting barrier characteristics were. No estimate of deltaV has been provided due to limitation in NHTSA accident reconstruction software (WinSmash). This software does not include models of typical roadside barriers from which deltaV calculations can be made. This case provides a good example of flaws in currently available crash data. Other Similar Cases: 1997-41-14, 1997-73-37, 1997
24 4 Case 2000-13-113 Summary: DRIVER WAS NORTHBOUND IN THE RIGHT LANE ON A WET 2 LANE EXPRESSWAY WHEN SHE DRIFTED OFF THE RIGHT SHOULDER AND STRUCK A GUARDRAIL HEAD-ON. THE NEWLY INSTALLED GUARDRAIL DID NOT HAVE THE END ATTENUATOR INSTALLED AND WAS DRIVEN THROUGH THE WINDSHIELD, STRIKING THE DRIVER AND CONTINUING OUT THROUGH THE BACKLIGHT. THE DRIVER WAS FATALLY INJURED. Vehicle Body Type Make Model Year Occ.# Age Occupantâs sex Maximum known occupant ais 1 2DR SEDAN/HT/CPE Oldsmobile Cutlass FWD 1991 1 44 FEMALE- NOT PREG 6 = MAXIMUM INJURY Figure 2.09: Case 4: Summary
25 Occupant: 2000-13-113-1-1 Rollover Classification Number of Harmful Events 1 Rollover Initiation Type NO ROLLOVER Location of Rollover Initiation NO ROLLOVER Rollover Initiation Object NO ROLLOVER Contacted Location on Vehicle where Principal Tripping Force was Applied NO ROLLOVER Direction of Initial Roll NO ROLLOVER Crash Severity Nr. Quarter Turns NO ROLLOVER Impact Speed < 0.5KMPH Total, Longitudal, and < 0.5 KMPH < 0.5 KMPH < Lateral delta-V 0.5 KMPH Estimated delta-V with DELTA V CODED 1 Sequence Number CDC 12 F D E W 3 Run off Road Damage (C1-C6) 19 40 64 66 35 33 Crush (L and D) 140 0 Pre-Crash Environment Traffic Flow DIVIDED/NO BARRIER Number of Travel Lanes TWO Roadway Alignment STRAIGHT Roadway Profile DOWNHILL GRADE Roadway Surface Type ASPHALT Roadway Surface Condition WET Light Conditions DARK Atmospheric Conditions RAIN Relation to Intersection NONINTER/NONJUNC Traffic Control Device Police Reported Alcohol ALCOHOL PRESENT Presence Alcohol Test (< 95 indicates 1 BAC 0.xx) Vehicle Factors Make-Model Oldsmobile Cutlass FWD Year 1991 Class PASSENGER CAR Body Type 2DR SEDAN/HT/CPE Weight 114 NASS Weighting Factor Weighting factor 86.712829417 Pre-Crash Driver Data Accident Type 1 Pre-event Movement GOING STRAIGHT Critical Pre-crash Event OFF EDGE-RIGHT Attempted Avoidance NO AVOIDANCE Maneuver Pre-impact Stability TRACKING Pre-impact Location DEPARTED ROADWAY DRIVER Factors Age 44 Height 160 Weight 61 Gender FEMALE-NOT PREG Restrain NONE USED/AVAIL Airbag Deployment NOT EQUIP/AVAIL Ejection NO EJECTION Ejection Area NO EJECTION Entrapment NOT ENTRAPPED Airbag Deployment â 1st Seat NOT EQUIP/AVAIL Airbag Deployment â Other NOT EQUIP W/ OTH Seat AOPS YES-RES DET Injuries Occupant 1 MAIS 6 = MAXIMUM INJURY Seat Position FRONT LEFT SIDE AIS Level Region Injured Contacts 3 = SERIOUS INJURY HEAD-SKULL STEERING RIM Figure 2.10: Case 4: Crash Information
26 Case 5: 1997-12-114 This case indicates correct performance of a guardrail where a severe injury still occurred. In this case a Mercury Sable left the road and impacted a double W-beam guardrail installation (mounted one above the other). The angle of impact was not severe, the driver was belted but she sustained severe injuries to her arm. Evidence of significant steering wheel loading is seen which may have lead to the serious (AIS-3) lower arm injury. The deformation of the vehicle and barrier system is not well documented however; a significant amount of barrier penetration has taken place. In addition, sections of the upper beam have failed which contributed to the extreme frontal damage to the vehicle. The presence of the stiff bumper point may have caused the rupture of the W beam (in a manner similar to the results of section 3.4). This behavior during deformable longitudinal barrier interaction was detrimental. However, the presence of the lower section here may have prevented subsequent barrier penetration. Important Factors ⢠Frame Rail Spread ⢠Barrier Installation ⢠Researcher Determined Impact Angle Other Similar Cases: 1998-2-148, 1998-9-123, 1998-9-72, 1999-41-65, 1999-75-70, 2000-43-115
27 5 Case 1997-12-114 Summary: V1 WAS SOUTHBOUND ON AN EXPRESSWAY. THERE WAS AN OBJECT IN THE CENTER LANE WHICH THE DRIVER SUCCESSFULLY AVOIDED, BUT STILL LOST CONTROL OF THE VEHICLE AFTER OVER CORRECTING AND LEFT THE ROADWAY STRIKING A GUARDRAIL MORE THAN ONCE. THE VEHICLE WAS TOWED, AND THE DRIVER WAS TAKEN TO A LOCAL FACILITY FOR TREATMENT OF INJURIES. Vehicle Body Type Make Model Year Occ.# Age Occupantâs sex Maximum known occupant ais 1 4-DR SEDAN/HDTOP Mercury Sable 1989 1 52 FEMALE- NOT PREG 3 = SERIOUS INJURY Figure 2.11: Case 5: Summary
28 Occupant: 1997-12-114-1-1 Rollover Classification Number of Harmful Events 3 Rollover Initiation Type NO ROLLOVER Location of Rollover Initiation NO ROLLOVER Rollover Initiation Object NO ROLLOVER Contacted Location on Vehicle where Principal Tripping Force was Applied NO ROLLOVER Direction of Initial Roll NO ROLLOVER Crash Severity Nr. Quarter Turns NO ROLLOVER Impact Speed < 0.5 KMPH Total, Longitudal, and < 0.5 KMPH < 0.5 KMPH < Lateral delta-V 0.5 KMPH Estimated delta-V with MODERATE 1 Sequence Number CDC 1 F D E W 1 Run off Road Damage (C1-C6) 2 7 0 0 0 0 Crush (L and D) 155 0 Pre-Crash Environment Traffic Flow ONE WAY Number of Travel Lanes THREE Roadway Alignment STRAIGHT Roadway Profile LEVEL Roadway Surface Type ASPHALT Roadway Surface Condition DRY Light Conditions DAY LIGHT Atmospheric Conditions NO ADVERSE COND Relation to Intersection NONINTER/NONJUNC Traffic Control Device Police Reported Alcohol NO ALCOHOL Presence Alcohol Test (< 95 indicates 0 BAC 0.xx) Vehicle Factors Make-Model Mercury Sable Year 1989 Class PASSENGER CAR Body Type 4DR SEADAN/HT Weight 141 NASS Weighting Factor Weighting factor 98.655342224 Pre-Crash Driver Data Accident Type 2 Pre-event Movement SUCES AVOID PREV Critical Pre-crash Event OTH CRIT EVENT Attempted Avoidance BRAKE+STEER RT Maneuver Pre-impact Stability LATERAL SKID-CLK Pre-impact Location DEPARTED ROADWAY DRIVER Factors Age 52 Height 160 Weight 122 Gender FEMALE-NOT PREG Restrain LAP AND SHOULDER Airbag Deployment NOT EQUIP/AVAIL Ejection NO EJECTION Ejection Area NO EJECTION Entrapment NOT ENTRAPPED Airbag Deployment â 1st Seat NONDEPLOYED Airbag Deployment â Other NOT EQUIP W/ OTH Seat AOPS NO Injuries Occupant 1 MAIS 3 = SERIOUS INJURY Seat Position FRONT LEFT SIDE Body Regions with MAIS 3+ Injuries AIS Level Region Injured Contacts 3 = SERIOUS INJURY FOREARM LEFT INTERIOR 3 = SERIOUS INJURY FOREARM LEFT INTERIOR Figure 2.12: Case 5: Crash Information
29 Case 6: 1998-6-31 End Terminal - Door Penetration This case is an example of a guardrail terminal penetration into the side structure of a car. In this case, a Lexus GS 300 lost control and spun into the median. Once off of the road, the car impacted the guardrail end at the driver's side door. Due to the lack of rigid structure within the door, the guardrail penetrated the occupant compartment and caused serious injuries to the driver's thigh. The case presented the need for the guardrail end to engage the door sill/rocker panels of automobiles. In side impact, the rocker panel is a major structural element. If this feature is engaged, the vehicle stiffness should exceed that of the barrier system leading to controlled deformation at the end terminal system. Important Factors ⢠Door Sill Height ⢠Average Door Sill Height for Full Size Vehicles ⢠End Terminal Height Other Similar Cases: 1999-49-209
30 6 Case 1998-6-31 Summary: V1 TRAVELING EAST ON A 3 LANE, 1 WAY HIGHWAY. THE BACK OF V1 WAS HIT BY AN UNKNOWN VEHICLE. V1 ROTATED COUNTERCLOCKWISE AND IMPACTED A GUARDRAIL WITH ITS LEFT SIDE. V1 CAME TO FINAL REST FACING EAST. A SERIOUS INJURY WAS REPORTED. THE VEHICLE WAS TOWED FROM THE SCENE. Vehicle Body Type Make Model Year Occ.# Age Occupantâs sex Maximum known occupant ais 1 4-DR SEDAN/HDTOP Lexus GS-300 1993 1 18 MALE 3 = SERIOUS INJURY Figure 2.13: Case 6: Summary
31 Occupant: 1998-6-31-1-1 Rollover Classification Number of Harmful Events 2 Rollover Initiation Type NO ROLLOVER Location of Rollover Initiation NO ROLLOVER Rollover Initiation Object NO ROLLOVER Contacted Location on Vehicle where Principal Tripping Force was Applied NO ROLLOVER Direction of Initial Roll NO ROLLOVER Crash Severity Nr. Quarter Turns NO ROLLOVER Impact Speed < 0.5 KMPH Total, Longitudal, and < 0.5 KMPH < 0.5 KMPH < Lateral delta-V 0.5 KMPH Estimated delta-V with >24 AND <40 KMPH 2 Sequence Number CDC 11 L Y A W 3 Run off Road Damage (C1-C6) 10 10 20 40 13 6 Crush (L and D) 350 5 Pre-Crash Environment Traffic Flow DVDED/W/BARRIER Number of Travel Lanes THREE Roadway Alignment CURVE LEFT Roadway Profile LEVEL Roadway Surface Type CONCRETE Roadway Surface Condition WET Light Conditions DARK/LIGHTED Atmospheric Conditions NO ADVERSE COND Relation to Intersection INTERCHANGE REL Traffic Control Device Police Reported Alcohol NO ALCOHOL Presence Alcohol Test (< 95 indicates 0 BAC 0.xx) Vehicle Factors Make-Model Lexus GS-300 Year 1993 Class PASSENGER CAR Body Type 4DR SEADAN/HT Weight 166 NASS Weighting Factor Weighting factor 8.6703603942 Pre-Crash Driver Data Accident Type 7 Pre-event Movement NEGOTIATE CURVE Critical Pre-crash Event OVER LINE LEFT Attempted Avoidance NO AVOIDANCE Maneuver Pre-impact Stability LATERAL SKID-CTR CLK Pre-impact Location DEPARTED ROADWAY DRIVER Factors Age 18 Height 178 Weight 74 Gender MALE Restrain NONE USED/AVAIL Airbag Deployment NOT EQUIP/AVAIL Ejection NO EJECTION Ejection Area NO EJECTION Entrapment NOT ENTRAPPED Airbag Deployment â 1st Seat NONDEPLOYED Airbag Deployment â Other NOT EQUIP W/ OTH Seat AOPS YES-RES DET Injuries Occupant 1 MAIS 3 = SERIOUS INJURY Seat Position FRONT LEFT SIDE Body Regions with MAIS 3+ Injuries AIS Level Region Injured Contacts 3 = SERIOUS INJURY THIGH LEFT HARDWARE Figure 2.14: Case 6: Crash Information
32 Case 7: 1997-41-51 During this case, a Ford Explorer collided with another passenger vehicle. This force the Explorer to veer into concrete median barrier at a fairly steep impact angle (estimated 45 deg.). Upon impact the interaction with the barrier lead to a counterclockwise rotation of the Explorer followed by a roll onto its right side. Important Factors ⢠Frontal Overhang of Ford Explorer ⢠Average Frontal Overhang of Mid-Size SUVs ⢠Researcher Determined Impact Angle
33 7 Case 1997-41-51 Summary: V1 WAS TRAVELING SOUTHBOUND ON SIX LANE INTERSTATE ROADWAY, ROAD SURFACE BLACKTOP, LEVEL, WET DURING DAYLIGHT HOURS. V1 WAS IN SIXTH LANE. V2 WAS TRAVELING SOUTHBOUND IN FORTH LANE WHEN V1 COLLIDED WITH RIGHT SIDE AT WHICH TIME V2 VEERED LEFT STRICKING CONCRETE MEDIAN WITH FRONT THEN ROTATED IN COUNTERCLOCKWISE ROTATION AND FLIPPING OVER ONTO RIGHT SIDE COMINT TO FINAL REST FACING S/E. V3 WAS TRAVELING SOUTHBOUND IN FORTH LANE WHEN V1 CAME TO FINAL; REST IN FORTH LANE,V3 COLLIDED WITH THE REAR OF V1. V1 and V2 WERE TOWED FROM SCENE, V3 LEFT SCENE UNDER OWN POWER, DRIVERS OF V1 and V2 PLUS PASSENGERS IN V1 WERE TRANSPORTED TO A MEDICAL FACILITY. Vehicle Body Type Make Model Year Occ.# Age Occupantâs sex Maximum known occupant ais 1 4-DR SEDAN/HDTOP Chrysler Lebaron 1987 1 35 FEMALE- NOT PREG 1 = MINOR INJURY 1 4-DR SEDAN/HDTOP Chrysler Lebaron 1987 2 6 MALE 0 = NOT INJURED 1 4-DR SEDAN/HDTOP Chrysler Lebaron 1987 3 7 FEMALE- NOT PREG 1 = MINOR INJURY 2 COMPACT UTILITY Ford Bronco II 1995 1 31 MALE 3 = SERIOUS INJURY Figure 2.15: Case 7: Summary
34 Occupant: 1997-41-51-2-1 Rollover Classification Number of Harmful Events 4 Rollover Initiation Type BOUNCE-OVER Location of Rollover Initiation ROADSIDE/MEDIAN Rollover Initiation Object CONCRETE BARRIER Contacted Location on Vehicle where Principal Tripping Force was Applied END PLANE Direction of Initial Roll ROLL RIGHT Crash Severity Nr. Quarter Turns 1 QUARTER TURN Impact Speed 998 Total, Longitudal, and 27 -24 14 Lateral delta-V Estimated delta-V with DELTA V CODED 2 Sequence Number CDC 11 F D E W 2 Run off Road Damage (C1-C6) 0 0 0 0 0 0 Crush (L and D) 0 0 Pre-Crash Environment Traffic Flow DVDED/W/BARRIER Number of Travel Lanes SIX Roadway Alignment STRAIGHT Roadway Profile LEVEL Roadway Surface Type ASPHALT Roadway Surface Condition WET Light Conditions DAYLIGHT Atmospheric Conditions NO ADVERSE COND Relation to Intersection NONINTER/NONJUNC Traffic Control Device Police Reported Alcohol NO ALCOHOL Presence Alcohol Test (< 95 indicates 0 BAC 0.xx) Vehicle Factors Make-Model Ford Bronco II Year 1995 Class PASSENGER CAR Body Type COMPACT UTILITY Weight 192 NASS Weighting Factor Weighting factor 58.819306296 Pre-Crash Driver Data Accident Type 45 Pre-event Movement GOING STRAIGHT Critical Pre-crash Event SAME DIR-OV RGHT Attempted Avoidance NO AVOIDANCE Maneuver Pre-impact Stability TRACKING Pre-impact Location STAYED IN LANE DRIVER Factors Age 31 Height 193 Weight 95 Gender MALE Restrain LAP AND SHOULDER Airbag Deployment BAG DEPLOYED Ejection NO EJECTION Ejection Area NO EJECTION Entrapment NOT ENTRAPPED Airbag Deployment - 1st Seat DR PAS BAG DEPLY Airbag Deployment â Other NOT EQUIP W/ OTH Seat AOPS YES-RES DET Injuries Occupant 1 MAIS 3 = SERIOUS INJURY Seat Position FRONT LEFT SIDE Body Regions with MAIS 3+ Injuries AIS Level Region Injured Contacts 3 = SERIOUS INJURY THIGH TRANSMISS LEVER 3 = SERIOUS INJURY THIGH TRANSMISS LEVER Figure 2.16: Case 7: Crash Information
35 Case 8: 1997-6-92 In this case, a grossly overloaded (11 occupants) Isuzu Rodeo collided with a concrete barrier. This collision although minor, resulted in the rollover of the vehicle and serious injuries to the occupants. The driver (belted) did not sustain serious injuries; however, a two year old occupant who was unrestrained sustained serious injuries during the crash. This case exemplifies the difficulty in designing roadside hardware for SUVs. In the summary to this case, it appeared the vehicle impacted the barrier at a relatively shallow angle. It also appeared that the barrier performed as designed (i.e. redirect the vehicle). The vehicle photos appeared to confirm this. The damage to the vehicle was mostly due to the vehicle sliding along the ground. It is unclear how the vehicle interaction with the barrier on the right side lead to a positive roll direction about the longitudinal axis of the vehicle (roll right). It is speculated by the research team that the barrier introduced a slight instability to the Rodeo and the driver was unable to recover. Important Factors ⢠Height of Contact With Barrier ⢠CG Height of Isuzu Rodeo ⢠Average CG Height of Mid-Size SUVs ⢠Average CG Height of Full Size Pickup Trucks ⢠Researcher Determined Impact Angle
36 8 Case 1997-6-92 Summary: V1 TRAVELING EAST ON A 3 LANE POSITIVLY DIVIDED HIGHWAY. VEHICLE CONTACTED A BARRIER TO THE RIGHT SIDE AND THEN BOUNCED OFF ON ROLLED TO RIGHT SIDE COMING TO FINAL REST ON RIGHT SIDE FACING EAST. SERIOUS INJURIES REPORTED TO VEHICLE. TOWED FROM THE SCENE. Vehicle Body Type Make Model Year Occ.# Age Occupantâs sex Maximum known occupant ais 1 COMPACT UTILITY Isuzu Rodeo 1997 1 28 FEMALE- NOT PREG 1 = MINOR INJURY 1 COMPACT UTILITY Isuzu Rodeo 1997 2 27 FEMALE- NOT PREG 3 = SERIOUS INJURY 1 COMPACT UTILITY Isuzu Rodeo 1997 3 33 FEMALE- NOT PREG 1 = MINOR INJURY 1 COMPACT UTILITY Isuzu Rodeo 1997 4 2 MALE 3 = SERIOUS INJURY 1 COMPACT UTILITY Isuzu Rodeo 1997 5 8 MALE 1 = MINOR INJURY 1 COMPACT UTILITY Isuzu Rodeo 1997 6 7 FEMALE- NOT PREG 1 = MINOR INJURY 1 COMPACT UTILITY Isuzu Rodeo 1997 7 8 FEMALE- NOT PREG 1 = MINOR INJURY 1 COMPACT UTILITY Isuzu Rodeo 1997 8 3 FEMALE- NOT PREG 1 = MINOR INJURY 1 COMPACT UTILITY Isuzu Rodeo 1997 9 8 MALE 1 = MINOR INJURY 1 COMPACT UTILITY Isuzu Rodeo 1997 10 10 FEMALE- NOT PREG 0 = NOT INJURED 1 COMPACT UTILITY Isuzu Rodeo 1997 11 4 FEMALE- NOT PREG 0 = NOT INJURED Figure 2.17: Case 8: Summary
37 Occupant: 1997-6-92-1-4 Rollover Classification Number of Harmful Events 2 Rollover Initiation Type BOUNCE-OVER Location of Rollover Initiation ROADSIDE/MEDIAN Rollover Initiation Object CONCRETE BARRIER Contacted Location on Vehicle where Principal Tripping Force was Applied SIDE PLANE Direction of Initial Roll ROLL RIGHT Age 2 Height 61 Weight 23 Crash Severity Nr. Quarter Turns 1 QUARTER TURN Impact Speed < 0.5KMPH Total, Longitudal, and < 0.5 KMPH < 0.5 KMPH < Lateral delta-V 0.5 KMPH Estimated delta-V with MODERATE 2 Sequence Number CDC 0 R D A O 2 Run off Road Damage (C1-C6) 0 0 0 0 0 0 Crush (L and D) 0 0 Pre-Crash Environment Traffic Flow DVDED/NO BARRIER Number of Travel Lanes THREE Roadway Alignment STRAIGHT Roadway Profile LEVEL Roadway Surface Type ASPHALT Roadway Surface Condition DRY Light Conditions DAYLIGHT Atmospheric Conditions NO ADVERSE COND Relation to Intersection NONINTER/NONJUNC Traffic Control Device Police Reported Alcohol NO ALCOHOL Presence Alcohol Test (< 95 indicates 0 BAC 0.xx) Vehicle Factors Make-Model Isuzu Rodeo Year 1997 Class PASSENGER CAR Body Type COMPACT UTILITY Weight 181 NASS Weighting Factor Weighting factor 10.465799133 Pre-Crash Driver Data Accident Type 2 Pre-event Movement CHANGING LANES Critical Pre-crash Event OFF EDGE-RIGHT Attempted Avoidance STEERING LEFT Maneuver Pre-impact Stability TRACKING Pre-impact Location LEFT TRAVEL LANE PASSENGER Factors Age 2 Height 61 Weight 23 Gender MALE Restrain NONE USED/AVAIL Airbag Deployment NOT EQUIP/AVAIL Ejection NO EJECTION Ejection Area NO EJECTION Entrapment NOT ENTRAPPED Airbag Deployment - 1st Seat NOT DEPLOYED Airbag Deployment â Other NOT EQUIP W/ OTH Seat AOPS YES-RES DET Injuries Occupant 4 MAIS 3 = SERIOUS INJURY Seat Position FRONT ON/IN LAP Body Regions with MAIS 3+ Injuries AIS Level Region Injured Contacts 3 = SERIOUS INJURY FOREARM UNKNOWN SOURCE Figure 2.18: Case 8: Crash Information
38 Case 9: 1998-72-44 The events of this case include a Chevrolet Blazer drifting off of the left side of the road and impacting a concrete median barrier. This impact caused the Blazer to roll and resulted in a severe head injury for the driver. Although the vehicle experienced a deceleration severe enough to result in significant steering wheel deformation, the airbags in this vehicle did not deploy. It should be noted that the left front (driver- side) wheel was torn from the upper and lower a-arms due to the high interactive forces with the barrier as well. This case indicates that excessive conditions are not required to roll less stable SUVs. A sudden vertical loading of one wheel will initiate a rollover event. Although the Blazer drifted off of the road at a slight angle, there was enough roll moment to cause the vehicle to overturn. This case also suggests that airbag sensors in recent model vehicles may not be well suited to sense these off axis impacts with longitudinal barriers. This hypothesis requires additional investigation using crash testing of airbag equipped vehicles or simulation study. Unfortunately, in this case, the vehicle was already in the shop before the NASS investigator could photograph the damage. Since it was impossible to tell the exact location of vehicle impact with the barrier, the importance of a timely investigation was also illustrated. Important Factors ⢠Height of Contact With Barrier ⢠Slope of Roadway at Impact Point ⢠CG Height of Chevrolet Blazer ⢠Average CG Height of Mid-Size SUVs ⢠Average CG Height of Full Size Pickup Trucks ⢠Researcher Determined Impact Angle
39 9 Case 1998-72-44 Summary: V1 WAS TRAVELING SOUTHBOUND ON A TWO-LANE DIVIDED EXPRESSWAY RAMP IN THE SECOND TRAVEL LANE. V1 DRIFTED OFF TO THE LEFT SHOULDER AND IMPACTED THE CONCRETE BARRIER WITH ITS' FRONT PLANE. THIS IMPACT CAUSED V1 TO ROLL ONTO ITS' RIGHT SIDE AND SLIDE TO FINAL REST IN THE SECOND TRAVEL LANE. V1 WAS TOWED FROM THE SCENE AND THE DRIVER WAS TRANSPORTED TO THE HOSPITAL WITH "A" INJURIES. Vehicle Body Type Make Model Year Occ.# Age Occupantâs sex Maximum known occupant ais 1 COMPACT UTILITY Chevrolet S-10 Blazer 1995 1 45 FEMALE- NOT PREG 4 = SEVERE INJURY Figure 2.19: Case 9: Summary
40 Occupant: 1998-72-44-1-1 Rollover Classification Number of Harmful Events 2 Rollover Initiation Type BOUNCE-OVER Location of Rollover Initiation ROADSIDE/MEDIAN Rollover Initiation Object CONCRETE BARRIER Contacted Location on Vehicle where Principal Tripping Force was Applied END PLANE Direction of Initial Roll ROLL RIGHT Crash Severity Nr. Quarter Turns 1 QUARTER TURN Impact Speed < 0.5KMPH Total, Longitudal, and < 0.5 KMPH < 0.5 KMPH < Lateral delta-V 0.5 KMPH Estimated delta-V with DELTA V CODED 1 Sequence Number CDC 0 F 9 9 9 0 Run off Road Damage (C1-C6) 0 0 0 0 0 0 Crush (L and D) 0 0 Pre-Crash Environment Traffic Flow DVDED/W/BARRIER Number of Travel Lanes TWO Roadway Alignment CURVE LEFT Roadway Profile LEVEL Roadway Surface Type ASPHALT Roadway Surface Condition DRY Light Conditions DARK Atmospheric Conditions NO ADVERSE COND Relation to Intersection INTERCHANGE REL Traffic Control Device Police Reported Alcohol ALCOHOL PRESENT Presence Alcohol Test (< 95 indicates 20 BAC 0.xx) Vehicle Factors Make-Model Chevrolet S-10 Blazer Year 1995 Class PASSENGER CAR Body Type COMPACT UTILITY Weight 157 NASS Weighting Factor Weighting factor 6.5847139881 Pre-Crash Driver Data Accident Type 6 Pre-event Movement NEGOTIATE CURVE Critical Pre-crash Event OFF-EDGE-LEFT Attempted Avoidance NO AVOIDANCE Maneuver Pre-impact Stability TRACKING Pre-impact Location LEFT TRAVEL LANE DRIVER Factors Age 45 Height 168 Weight 98 Gender FEMALE-NOT PREG Restrain NONE USED/AVAIL Airbag Deployment NONDEPLOYED Ejection NO EJECTION Ejection Area NO EJECTION Entrapment NOT ENTRAPPED Airbag Deployment - 1 st Seat NONDEPLOYED Airbag Deployment â Other NOT EQUIP W/ OTH Seat AOPS YES-RES DET Injuries Occupant 1 MAIS 4 = SEVERE INJURY Seat Position FRONT LEFT SIDE Body Regions with MAIS 3+ Injuries AIS Level Region Injured Contacts 4 = SEVERE INJURY HEAD - SKULL FRONT HEADER Figure 2.20: Case 9: Crash Information
41 Case 10: 1998-49-184 This case involved a Ford Explorer that lost control on a 3 lane divided highway. In the first collision, the Explorer hit a concrete median barrier dividing the opposing lanes of traffic. During this collision, the driver was partially ejected and the driver's head impacted a light post adjacent to the roadway. The vehicle, after this collision, traveled across the roadway and collided into the concrete barrier on the opposite side of the roadway. The collision with this wall caused the vehicle to rollover, and the occupant was fully ejected. As a result of the first barrier impact, the Explorer climbed quite high on the barrier introducing enough vehicle motion to partially eject the unbelted occupant. During the second collision and following a severe head strike, the combined high impact angle and lack of driver control lead to the subsequent rollover event and complete occupant ejection. This case shows the necessity of controlling the lateral Delta-V during impact with roadside structures. In this case, a midsized SUV impacted a barrier with sufficient force to partially eject the driver. In addition, this case shows the need for proper vehicle to guardrail interaction so that rollover is not initiated after vehicles to guardrail interaction. Other similar cases: 1997-6-92, 1998-49-184, 1998-72-44, 1999-43-152, 1997-45-109,2000-49-107, 2000-79-15, 1997-12- 151, 1999-9-61, 1999-11-150, 1998-75-40, 1998-8-157, 1999-49-75, 1997-72-125 Important Factors ⢠Height of Contact With Barrier ⢠Profile of Impacted Barrier ⢠Lateral DeltaV for First Impact ⢠Researcher Determined Impact Angle for Second Impact
42 10 Case 1998-49-184 Summary: V1 WAS TRAVELING NB IN THE 1ST LANE OF A WET 3-LANE DIVIDED CONCRETE URBAN TOLLWAY. V2 WAS TRAVELING IN THE SAME LANE OF THE SAME ROADWAY. V1 BEGAN A CCW ROTATION CROSSED ALL LANES, AND IMPACTING THE CONCRETE RETAINING WALL, PARTIALLY EJECTING DRIVER ALSO CAUSING THE PARTIALLY EJECTED DRIVER TO IMPACT A LIGHT POLE WITH HIS HEAD. V1 CONTINUED BACK IN A CLOCKWISE ROTATION, AGAIN CROSSING THE THREE LANES AND A SHOULDER, IMPACTING THE RETAINING WALL ON THE EAST SIDE OF TRAFFIC. THEN ROLLED TO THE LEFT, EJECTING DRIVER. V1 THEN CAME TO REST FACING EAST ON THE CONCRETE SHOULDER. V2 WAS BEHIND V1 IN THE 1ST LANE AND, IN AN ATTEMPT TO AVOID V1 COMING BACK ACROSS THE TRAFFIC, TURNED RIGHT AND IMPACTED FRONT TO THE EAST RETAINING WALL AND CAME TO REST STILL NORTHBOUND ON THE SHOULDER JUST TO THE SOUTH OF V1. V1 WAS TOWED DUE TO DAMAGE AND THE DRIVER WAS PRONOUNCED DEAD AT THE SCENE. V2 WAS RELEASED AT THE SCENE. Vehicle Body Type Make Model Year Occ.# Age Occupantâs sex Maximum known occupant ais 1 COMPACT UTILITY Ford Bronco II 1993 1 24 MALE 6 = MAXIMUM INJURY Figure 2.21: Case 10: Summary
43 Occupant: 1998-49-184-1-1 Rollover Classification Number of Harmful Events 4 Rollover Initiation Type TRIP-OVER Location of Rollover Initiation ROADSIDE/MEDIAN Rollover Initiation Object GROUND Contacted Location on Vehicle where Principal Tripping Force was Applied WHEELS/TIRES Direction of Initial Roll ROLL LEFT Crash Severity Nr. Quarter Turns 4 QUARTER TURN Impact Speed < 0.5KMPH Total, Longitudal, and < 0.5 KMPH < 0.5 KMPH < Lateral delta-V 0.5 KMPH Estimated delta-V with MINOR 1 Sequence Number CDC 3 F D E W 1 Run off Road Damage (C1-C6) 0 0 2 4 5 6 Crush (L and D) 152 0 Pre-Crash Environment Traffic Flow DVDED/W/BARRIER Number of Travel Lanes THREE Roadway Alignment STRAIGHT Roadway Profile DOWNHILL GRADE Roadway Surface Type CONCRETE Roadway Surface Condition WET Light Conditions DARK/LIGHTED Atmospheric Conditions RAIN Relation to Intersection NONINTER/NONJUNC Traffic Control Device Police Reported Alcohol ALCOHOL PRESENT Presence Alcohol Test (< 95 indicates 24 BAC 0.xx) Vehicle Factors Make-Model Ford Bronco II Year 1993 Class PASSENGER CAR Body Type COMPACT UTILITY Weight 175 NASS Weighting Factor Weighting factor 6.8343921903 Pre-Crash Driver Data Accident Type 98 Pre-event Movement GOING STRAIGHT Critical Pre-crash Event TRAVEL TOO FAST Attempted Avoidance NO DRIVER Maneuver Pre-impact Stability NO DRIVER Pre-impact Location DEPARTED ROADWAY DRIVER Factors Age 24 Height 170 Weight 70 Gender MALE Restrain NONE USED/AVAIL Airbag Deployment NOT EQUIP/AVAIL Ejection COMPLETE EJECT Ejection Area LEFT FRONT Entrapment NOT ENTRAPPED Airbag Deployment - 1 st Seat NOT EQUIP/AVAIL Airbag Deployment â Other NOT EQUIP W/ OTH Seat AOPS NO Injuries Occupant 1 MAIS 6 = MAXIMUM INJURY Seat Position FRONT LEFT SIDE Body Regions with MAIS 3+ Injuries AIS Level Region Injured Contacts 6 = MAXIMUM INJURY HEAD - SKULL OTHER VEH OR OBJ Figure 2.22: Case 10: Crash Information
44 Case 11: 1998-49-71 This case involved a Jeep Grand Cherokee that failed to negotiate a right hand turn. The vehicle engaged a guardrail surrounding the turn, however the vehicle climbed over the guardrail and a roll was induced. Due to the roll, the driver was ejected came to rest between the vehicle and the ground. He died shortly after the collision due to his injuries. An investigation into the vehicle damage pictures shows that there was little damage to the front of the vehicle during the barrier impact. For this reason, it is believed that the vehicle mounted the barrier at the turned down end which began just after the start of the circular exit ramp. In addition, due to the lack of photographic evidence, it was impossible to know whether the barrier was ruptured during the collision. Therefore, in order to improve the effectiveness of this type of investigation, it would be helpful for investigators to visit crash scenes before roadside repairs are completed if possible. This case indicates the need for review of barrier installations particularly at critical locations like this one. It should be noted that the Grand Cherokee has a CG height which is lower than other mid-size SUVs in its class.
45 11 Case 1998-49-71 Summary: V1 ON EXIT RAMP FROM A N. BOUND DIRECTION TO W.BOUND. THE RAMP IS POSITIVELY SLOPED, CURVING RIGHT, SINGLE LANE OF DRY ASPHALT. V1 CONTACTED ITS FRONT LEFT CORNER WITH A GUARDRAIL - CLIMBED OVER THE RAILING, DID A COMPLETE ROLL, EJECTED DRIVER, CAME TO REST ON ITS LEFT PLANE ATOP DRIVER. VEH TOWED. DRIVER TRANSPORTED AND WAS LATER REPORTED DEAD, LESS THAN 1 HOUR AFTER CRASH. Vehicle Body Type Make Model Year Occ.# Age Occupantâs sex Maximum known occupant ais 1 COMPACT UTILITY Jeep Cherokee84 1998 1 30 MALE 5 = CRITICAL INJURY Figure 2.23: Case 11: Summary
46 Occupant: 1998-49-71-1-1 Rollover Classification Number of Harmful Events 2 Rollover Initiation Type CLIMB-OVER Location of Rollover Initiation ROADSIDE/MEDIAN Rollover Initiation Object OTHER BARRIER Contacted Location on Vehicle where Principal Tripping Force was Applied UNDERCARRIAGE Direction of Initial Roll ROLL LEFT Crash Severity Nr. Quarter Turns 5 QUARTER TURN Impact Speed < 0.5KMPH Total, Longitudal, and < 0.5 KMPH < 0.5 KMPH < Lateral delta-V 0.5 KMPH Estimated delta-V with MODERATE 2 Sequence Number CDC 0 T D D O 3 Run off Road Damage (C1-C6) 0 0 0 0 0 Crush (L and D) 0 0 Pre-Crash Environment Traffic Flow ONE WAY Number of Travel Lanes ONE Roadway Alignment CURVE RIGHT Roadway Profile UPHILL GRADE Roadway Surface Type ASPHALT Roadway Surface Condition DRY Light Conditions DARK/LIGHTED Atmospheric Conditions NO ADVERSE COND Relation to Intersection INTERCHANGE REL Traffic Control Device Police Reported Alcohol NO ALCOHOL Presence Alcohol Test (< 95 indicates 17 BAC 0.xx) Vehicle Factors Make-Model Jeep Cherokee 84 Year 1998 Class TRUCK Body Type COMPACT UTILITY Weight 169 NASS Weighting Factor Weighting factor 8.7992799451 Pre-Crash Driver Data Accident Type 6 Pre-event Movement NEGOTIATE CURVE Critical Pre-crash Event TRAVEL TOO FAST Attempted Avoidance NO DRIVER Maneuver Pre-impact Stability NO DRIVER Pre-impact Location DEPARTED ROADWAY DRIVER Factors Age 30 Height 168 Weight 84 Gender MALE Restrain NONE USED/AVAIL Airbag Deployment NONDEPLOYED Ejection COMPLETE EJECT Ejection Area LEFT FRONT Entrapment NOT ENTRAPPED Airbag Deployment - 1 st Seat NONDEPLOYED Airbag Deployment â Other NOT EQUIP W/ OTH Seat AOPS YES-RES DET Injuries Occupant 1 MAIS 5 = CRITICAL INJURY Seat Position FRONT LEFT SIDE Figure 2.24: Case 11: Crash Information
47 Case 12: 2000-9-15 In Case 2000-9-15, a Toyota 4-Runner impacted an Acura Integra. After this initial collision, the damaged 4-runner collided with the guardrail at a moderate angle. Unfortunately the guardrail did not contain the 4-runner, and the vehicle climbed the guardrail and started to roll. This roll however was averted by a collision with a light pole. Eventually the vehicle comes to rest in a ditch and with the driver sustaining incapacitating injuries. This case exemplified a failure of the guardrail to contain the vehicle. The 4-Runner, although damaged, should have hit the guardrail and come to rest. As it stood however, the vehicle was able to vault over the guardrail and only avoid a rollover by a secondary collision with a light pole. Investigation of the pictures of the guardrail and the vehicle showed that the guardrail in place was of a standard design and seemed to be installed properly. It was hypothesized that the vehicle was able to vault this guardrail because the point of impact was below the center of gravity. Therefore possible future designs should be able to engage the vehicle in a manner such that the projected point of impact is at or above the vehicle CG while avoiding vehicle under ride of the barrier. Other Similar Cases: 1999-73-12, 2000-48-169, 2000-9-15 Important Factors ⢠Frontal Overhang of Toyota 4-Runner ⢠Average Frontal Overhang for Midsize SUVs ⢠CG Height of Toyota 4-Runner ⢠Average CG Height of Mid-Size SUVs ⢠Average CG Height of Full Size Pickup Trucks ⢠Researcher Determined Impact Angle
48 12 Case 2000-9-15 Summary: V1, A 1997 ACURA INTEGRA WAS TRAVELING EAST, IN LANE THREE, OF A FOUR LANE DIVIDED HIGHWAY(JERSEY WALL LEFT GUARDRAIL RIGHT). V2, A 1997 TOYOTA 4-RUNNER SUV WAS TRAVELING THE SAME HIGHWAY, IN LANE NUMBER TWO. V1 SWERVES/CHANGES LANES TO THE RIGHT TO AVOID A DEAD ANIMAL IN THE ROADWAY. V2'S FRONT PLANE STRIKES V1'S RIGHT SIDE PLANE. V1 TRAVELS BACK ACROSS LANE THREE AND COMES TO REST IN LANE FOUR. V2 CROSSES LANE ONE AND DEPARTS THE ROADWAY TO THE RIGHT. V2 STRIKES A GUARDRAIL WITH IT'S FRONT PLANE. V2 CLIMBS THE GUARDRAIL, STARTS TO ROLL (NO ROLLOVER OCCURRED / LIGHT POLE IMPACT PREVENTED ROLL) AND BECOMES AIRBORNE. V2 THEN STRIKES A LIGHT POLE WITH ITS TOP PLANE (NON-HORIZONTAL). V2 THEN DESCENDS A STEEP EMBANKMENT (UNKNOWN IF STILL AIRBORNE) AND STRIKES MULTIPLE TREES AND THEIR RELATED BRANCHES WITH ITS UNDERCARRIAGE. V2 THEN STRIKES THE NEAR SIDE EMBANKMENT WITH ITS UNDERCARRIAGE AND COMES TO REST AT THE BOTTOM, IN A DITCH/GULLY (V2 AT REST ON ALL FOUR WHEELS). BOTH VEHICLES ARE TOWED. THE DRIVER AND SOLE OCCUPANT OF V1 IS NOT INJURED OR TRANSPORTED. THE DRIVER AND SOLE OCCUPANT OF V2 IS TRANSPORTED AND HOSPITALIZED WITH INCAPACITATING INJURIES. Vehicle Body Type Make Model Year Occ.# Age Occupantâs sex Maximum known occupant ais 1 3DR/2DR HATCHBAK Acura Integra 1997 1 26 MALE 0 = NOT INJURED 2 COMPACT UTILITY Toyota 4-Runner 1997 1 47 FEMALE- NOT PREG 5 = CRITICAL INJURY Figure 2.25: Case 12: Summary
49 Occupant: 2000-9-15-1-1 Rollover Classification Number of Harmful Events 5 Rollover Initiation Type NO ROLLOVER Location of Rollover Initiation NO ROLLOVER Rollover Initiation Object NO ROLLOVER Contacted Location on Vehicle where Principal Tripping Force was Applied NO ROLLOVER Direction of Initial Roll NO ROLLOVER Crash Severity Nr. Quarter Turns NO ROLLOVER Impact Speed 998 Total, Longitudal, and 33 11 -31 Lateral delta-V Estimated delta-V with DELTA V CODED 1 Sequence Number CDC 4 R P A W 3 Run off Road Damage (C1-C6) 3 22 40 43 11 2 Crush (L and D) 200 23 Pre-Crash Environment Traffic Flow DIVIDED/W/BARRIER Number of Travel Lanes FOUR Roadway Alignment CURVE LEFT Roadway Profile UPHILL GRADE Roadway Surface Type ASPHALT Roadway Surface Condition DRY Light Conditions DAY LIGHT Atmospheric Conditions NO ADVERSE COND Relation to Intersection NONINTER/NONJUNC Traffic Control Device Police Reported Alcohol NO ALCOHOL Presence Alcohol Test (< 95 indicates 0 BAC 0.xx) Vehicle Factors Make-Model Acura Integra Year 1997 Class PASSENGER CAR Body Type 3DR/2DR HATCHBACK Weight 115 NASS Weighting Factor Weighting factor 35.411450506 Pre-Crash Driver Data Accident Type 46 Pre-event Movement CHANGING LANES Critical Pre-crash Event OVER LINE - RIGHT Attempted Avoidance STEERING RIGHT Maneuver Pre-impact Stability NO DRIVER Pre-impact Location LEFT TRAVEL LANE DRIVER Factors Age 26 Height 178 Weight 64 Gender MALE Restrain LAP AND SHOULDER Airbag Deployment NONDEPLOYED Ejection NO EJECTION Ejection Area NO EJECTION Entrapment NOT ENTRAPPED Airbag Deployment â 1st Seat NONDEPLOYED Airbag Deployment â Other NOT EQUIP W/ OTH Seat AOPS YES-RES DET Injuries Occupant 1 MAIS 0 = NOT INJURED Seat Position FRONT LEFT SIDE Figure 2.26: Case 12: Crash Information
50 Case 13: 1998-12-54 A Jeep Grand Cherokee lost control while traveling and struck its left rear on a concrete retaining wall. The driver, while trying to regain control, then hit another guardrail with the left front of the vehicle. The collision with the retaining wall redirected the vehicle back into traffic where it collided with a Chevrolet Pick-up. This T-bone collision resulted in severe injuries for the driver of the Grand Cherokee. The concrete wall in this case showed an incompatibility due to of the high re-direction angle of the bullet vehicle. When the driver of the Cherokee hit the guardrail the second time, he was not traveling at a high angle in relation to the retaining wall. Therefore, the vehicle should have come to rest against the guardrail or a short distance away. As it happened, the vehicle was redirected sharply into traffic, which resulted in a second, T-bone, collision with a full size pick-up truck. ⢠Redirection Angle following Initial Barrier Impact ⢠Frontal Overhang of Grand Cherokee ⢠Average Frontal Overhang for Midsize SUVs ⢠CG Height of Jeep Grand Cherokee ⢠Average CG Height of Mid-Size SUVs ⢠Average CG Height of Full Size Pickup Trucks ⢠Researcher Determined Impact Angle
51 13 Case 1998-12-54 Summary: VEHICLE ONE WAS HEADING EAST ON A TWO LANE, TWO WAY, ICY, ASPHALT ROADWAY. V2 WAS HEADING WEST ON THE SAME ROADWAY. V1 LOST CONTROL ON AN ICY OVERPASS AND STRUCK THE LEFT, BACK OF THE VEHICLE ON A CONCRETE BARRIER. THE VEHICLE BOUNCED OFF THE BARRIER AND CONTINUED IN A SOUTH EASTERLY DIRECTION. V1, STILL SLIDING ON THE ICE, THEN HIT A GUARDRAIL WITH THE LEFT, FRONT, GLANCING OFF AND HEADING INTO ONCOMING TRAFFIC. WITH VEHICLE ONE IN ITS TRAVEL OF PATH, THE FRONT OF V2 CONTACTED THE LEFT SIDE OF V1. BOTH VEHICLES WERE TOWED DUE TO DAMAGE. OCCUPANTS ONE AND THREE OF V1 WERE KILLED IN THIS ACCIDENT. OCCUPANT TWO OF V1 WAS TRANSPORTED FOR MEDICAL TREATMENT. OCCUPANTS 1 AND 2 OF V2 WERE TRANSPORTED FOR MEDICAL TREATMENT. ALL OCCUPANTS INVOLVED IN THIS ACCIDENT WERE WEARING LAP AND SHOULDER BELTS. Vehicle Body Type Make Model Year Occ.# Age Occupantâs sex Maximum known occupant ais 1 COMPACT UTILITY Jeep Cherokee84 1993 1 34 FEMALE- NOT PREG 2 = MODERATE INJURY 1 COMPACT UTILITY Jeep Cherokee84 1993 2 8 MALE 5 = CRITICAL INJURY 1 COMPACT UTILITY Jeep Cherokee84 1993 3 7 FEMALE- NOT PREG 7 = INJURY, UNK SEV 2 COMPACT PICKUP Chevrolet S-10 1982 1 31 MALE 1 = MINOR INJURY 2 COMPACT PICKUP Chevrolet S-10 1982 2 31 MALE 1 = MINOR INJURY Figure 2.27: Case 13: Summary
52 Occupant: 1998-12-54-1-2 Rollover Classification Number of Harmful Events 3 Rollover Initiation Type NO ROLLOVER Location of Rollover Initiation NO ROLLOVER Rollover Initiation Object NO ROLLOVER Contacted Location on Vehicle where Principal Tripping Force was Applied NO ROLLOVER Direction of Initial Roll NO ROLLOVER Crash Severity Nr. Quarter Turns NO ROLLOVER Impact Speed 998 Total, Longitudal, and 45 â22 39 Lateral delta-V Estimated delta-V with DELTA V CODED 3 Sequence Number CDC 10 L D A W 3 Run off Road Damage (C1-C6) 17 36 20 39 12 0 Crush (L and D) 286 -53 Pre-Crash Environment Traffic Flow NOT DIVIDED Number of Travel Lanes TWO Roadway Alignment STRAIGHT Roadway Profile LEVEL Roadway Surface Type ASPHALT Roadway Surface Condition ICE Light Conditions DARK Atmospheric Conditions NO ADVERSE COND Relation to Intersection NONINTER/NONJUNC Traffic Control Device Police Reported Alcohol NO ALCOHOL Presence Alcohol Test (< 95 indicates 0 BAC 0.xx) Vehicle Factors Make-Model Acura Integra Year 1997 Class PASSENGER CAR Body Type 3DR/2DR HATCHBACK Weight 115 NASS Weighting Factor Weighting factor 32.466587775 Pre-Crash Driver Data Accident Type 9 Pre-event Movement GOING STRAIGHT Critical Pre-crash Event POOR ROAD CONDIT Attempted Avoidance NO DRIVER Maneuver Pre-impact Stability TRACKING Pre-impact Location LEFT TRAVEL LANE DRIVER Factors Age 8 Height 122 Weight 34 Gender MALE Restrain LAP AND SHOULDER Airbag Deployment NOT EQUIP/AVAIL Ejection NO EJECTION Ejection Area NO EJECTION Entrapment NOT ENTRAPPED Airbag Deployment â 1st Seat NONDEPLOYED Airbag Deployment â Other NOT EQUIP W/ OTH Seat AOPS YES-RES DET Injuries Occupant 2 MAIS 5 = CRITICAL INJURY Seat Position SECOND LEFT Figure 2.28: Case 13: Crash Information
53 2.2.1 Case Review Summary The NASS/CDS cases reviewed above indicate that a series of vehicle and roadside device characteristics are critical for the proper performance of the vehicle/roadway system in the event of a crash. These characteristics are as follows: ⢠Vehicle CG height ⢠Vehicle Frontal Overhang (propensity for Snagging) ⢠Vehicle Mass ⢠Roadway Profile and Design ⢠Barrier Height ⢠Impact Severity (i.e. deltaV) The current vehicle fleet is shifting towards a higher percentage of larger SUV, crossover and pickup style vehicles. These vehicles have higher ground clearances, shorter frontal overhangs and higher CGs. This combination of characteristics leads to greater risk of negative interaction with barrier systems. This interaction includes barrier snagging, tearing and overriding. The cases reviewed indicate that subsequent instability of higher CG vehicles is often involved in subsequent rollovers and increases injury risk. This behavior must be improved from the vehicle design perspective as well as design of the barrier systems so that this rollover propensity is reduced. For the passenger car fleet, favorable interaction with the longitudinal sections of the barriers is observed. Few vehicle penetrations, high redirective accelerations or vehicle rollovers were found in the crash cases. The deployment timing of airbags during vehicle/roadside hardware crashes is in question however. As airbag systems are designed to deploy based on deceleration of the vehicle structure in the event of a crash, low acceleration forces brought about by longitudinal barrier interaction may lead to delays in deployment from first contact. To determine if any negative effects are brought about by airbags and soft barrier systems further crash investigation is required. In the future, enhanced crash testing procedures should be used which include airbag equipped vehicles, human surrogates to measure crash forces and visual documentation of belted occupants to understand their kinematics in the event of an oblique barrier crash. Automotive manufacturers should consider the nature of vehicle crash signatures to ensure that
54 vehicle sensor systems and deployment algorithms effectively select deployment regimes to best protect occupants. This testing should be conducted for all vehicle body types.
