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Los Angeles Sheriff Tests 2009 Vehicles
Each year since 1974, the Los Angeles County Sheriff’s Department has conducted performance and fuel economy tests on police vehicles. With a total square mileage about the size of the state of Connecticut, Los Angeles County has widely diverse operating conditions ranging from traffic-clogged urban streets, winding mountainous roadways, scorching deserts, and high-speed freeways. For 2009, only pursuit-capable vehicles were tested; the special service vehicles like the Chevy Tahoe 4x4 and Ford Explorer were not tested.
For next year, another change will take place. For almost 50 years, the combined LASD-LAPD vehicle testing has taken place at the Pomona Fairplex Complex, where the Los Angeles County Fair is held. This was the final year of testing at the Fairplex. Next year the testing will be held at the Auto Club Dragway in Fontana, which lies midway between Ontario and San Bernardino.
The current LASD program dates back to the early 1970s, when it took over from the Los Angeles Police Department, which began testing police vehicles in 1956! The current testing actually involves both the LASD and the LAPD as both agencies supply EVOC instructors to evaluate the vehicles and experienced motorcycle officers to evaluate the motorcycles.
In comparison with the annual vehicle tests performed by the Michigan State Police, the Los Angeles Sheriff testing program places less emphasis on top speeds and places more emphasis on handling, braking, and mechanical reliability. All of the 2009 vehicles submitted successfully passed all of the test phases.
Preliminary Handling Test
All vehicles begin the test series with the Preliminary Handling Test. This is a 1.57-mile high-speed driving course laid out at the “Fairplex” Complex. Each vehicle is driven eight laps by each test driver. Four test drivers are used for each vehicle, for a total of 32 laps. The speeds of the pursuit-certified vehicles on this high-speed course average between 64 mph and 70 mph.
Speeds and times were measured by using a GPS-based “V-BOX Datalogger” mounted in the vehicle. Both the fastest and slowest laps are automatically eliminated, and the remaining six laps are averaged. Each driver also subjectively and independently evaluates each vehicle at the end of this phase. Vehicles that are rated as “unacceptable” are disqualified and are not allowed to participate in further testing.
The fastest police vehicle during on the Preliminary Handling Test was the 5.7L Dodge Charger sedan, with the slowest being the Tahoe, with a little over 6 seconds time difference between fastest and slowest. Of the police sedans, the difference between the Charger and the Impala measured to a difference of a little under 4 seconds.
Immediately after the Preliminary Handling Test, the brakes are tested. This simulates actual police operating conditions with hot brakes and tires, such as after an emergency run or pursuit situation. This also makes this brake test the hardest, most severe brake test performed by the police community. All of the brake testing was conducted in the same area of a smooth portion of the asphalt track surface, thus maintaining the same coefficient of friction during the testing. These are average distances. As with the Preliminary Handling Tests, the VBOX Datalogger, a GPS-based measuring device, was used to measure stopping distances.
The test vehicle is accelerated up to a speed of 80 mph, and the brakes are applied to maintain a deceleration rate of 22 fps2 without ABS activation. This test is repeated three additional times. The vehicle is allowed to sit stationary for five minutes. The vehicle is then accelerated to a speed of 60 mph and is decelerated at a maximum rate, just short of Antilock Brake System (ABS) activation. After a two-minute, heat-soak period, the procedure is repeated. The vehicle is then accelerated to 60 mph and the vehicle is stopped to simulate a “panic-stop” with ABS activation.
Any malfunctions (fade or pulling) are investigated to determine the cause. If the cause is correctable, then the vehicle is allowed to be repaired and retested. If it appears that the defect is an engineering issue or design flaw, then the vehicle is disqualified from further testing.
The police sedan with the best brakes this year was the 3.5L Dodge Charger which recorded a 140.3-foot stopping distance during this test phase.
The VBOX Datalogger also recorded acceleration times at all speeds up to 100 mph. Standing start, ¼-mile acceleration is also measured, but maximum top speeds are not attempted.
The police sedan with the fastest acceleration to 60 mph and to 100 mph was the 5.7L Dodge Charger with times of 7.2 seconds and 14.9 seconds, respectively. In the standing start ¼-mile acceleration run, the HEMI® Charger went through the traps with an elapsed time of 15.3 seconds and 101.3 mph.
The final test of pursuit vehicles is the Pursuit Course. This is limited to vehicles that are rated as police package (pursuit-certified) by the vehicle’s manufacturers. This is a 2.45-mile course that simulates a pursuit situation within an urban environment, consisting of a maze of twisting right- and left-hand turns, along with obstacles littering the roadway.
Two test drivers are used to evaluate each vehicle, and times are recorded on the VBOX Datalogger mounted in the vehicle. Each driver completes two laps around this course. A vehicle is deemed unacceptable if it cannot complete the four-lap course in less than a combined time of 4 minutes, 45 seconds. Before participating in the Pursuit Course, at their option, the vehicle representatives were given the opportunity to rebuild the brake systems, however, this year none of the manufacturers exercised this option and went directly on to the Pursuit Course.
The fastest vehicle through the Pursuit Course was the 5.7L Charger. The 3.5L Charger was clearly second overall and well ahead of the four-car cluster of Ford CVPI (3.55, 3.27) and Impala (gas, E85).
Ergonomics / Fuel Efficiency Testing:
The Fuel Efficiency Test simulates real-world conditions and is conducted over a 100-mile course. In the past, one test driver drove each vehicle through the course during lighter traffic conditions. The current protocol uses patrol deputies, in full uniform, to run each vehicle through this course. Each vehicle is driven through the course four times with different drivers, during peak (rush-hour) traffic conditions.
The course is divided equally with urban, suburban and freeway driving conditions. Standard pump gasoline was used, even on E85-compatible versions. The vehicle’s headlights and air-conditioning are turned on, and the transmissions are placed in the “Overdrive” position. The vehicles are driven in a normal manner, i.e., the vehicles are neither driven gently nor driven for maximum performance. The fuel mileage obtained from each run is then averaged. By definition, this test simulates the mileage that a detective or administrative vehicle would obtain. Experience shows that a marked patrol unit would obtain about 60% to 70% of these mileage figures.
Each deputy fills out a checklist rating his impression of each individual vehicle. The evaluations are conducted separately, and the ratings are averaged to minimize any individual prejudices for or against any of the vehicles. Vehicles are evaluated for general suitability and efficiency as a patrol vehicle, or other specific functions that the LASD may require.
The police sedans with the best gas mileage under these test conditions were a tie between the 3.55-geared Crown Victoria and the 3.5L Dodge Charger at 17.1 mpg. The 3.9L V-6 Chevy Impala and the 5.7L V-8 Charger also got the same fuel economy at 16.6 mpg.
The 2009 Impala is a tad quicker compared to last year’s car. Drivers commented that this vehicle was well balanced and easy to drive fast with confidence. They also commented that the drivetrain produced excellent power, coupled with shift points that are well matched to the engine’s torque curve.
The drivers and evaluators gave the Tahoe high praise for driver comfort, i.e., large doors, interior space, legroom, visibility and ease of reaching controls. While power on the upper end was adequate, some drivers felt bottom-end performance was disappointing, and the ratio between second and third gears was too wide. They also commented that that while it is predictable, it always lets you know that it is a large, heavy vehicle.
The Dodge Charger
One test driver commented that the V-8 version of the Dodge Charger felt stronger than previous versions and the chassis is well matched to the HEMI engine. Another driver said the ESP will prevent the driver from driving too aggressively. The 3.5L V-6 version also received high praise. One driver described the 2009 as “The best V-6 Charger yet…easy and confidence inspiring to drive.” Another tester commented on the brakes, stating there was absolutely no fade, not sure I used all the brakes available.”
The Ford Crown Victoria Police Interceptor got the usual got high marks for handling, power range and shift-points, with one officer saying the 2009 was “the best Crown Victoria I have driven to date.”
While the Los Angeles County Sheriff’s testers do not recommend any specific vehicle or tire, their test results are published. For further information on the program, contact or copies of the complete report contact: Los Angeles County Sheriff’s Department Communications and Fleet Management Bureau, 1104 N. Eastern Ave., Door #50, Los Angeles, CA 90063 and phone (323) 267-2511.
John Bellah is a recently retired police officer who served in Southern California for more than 31 years. He can be contacted at email@example.com.
Published in Police Fleet Manager, Mar/Apr 2009
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