Dupont Trolley Industries Download PDF Report
Dupont Industries Inc. submitted a model M 2000, diesel-powered, 25 seat/28-foot bus, for a 12 yr/500,000 mile STURAA test. The odometer reading at the time of delivery was 34,796 miles. Testing started on October 17, 2000 and was completed on May 2, 2001. The Check-In section of the report provides a description of the bus and specifies its major components.
The primary part of the test program is the Structural Durability Test, which also provides the information for the Maintainability and Reliability results. The Structural Durability Test started on October 30, 2000 and was completed on April 16, 2001.
The first segment of the Structural Durability Test was performed with the bus loaded to a GVW of 24,375 lbs. The middle segment was performed at a seated load weight of 21,075 lbs. and the final segment was performed at a curb weight of 17,000 lbs. Durability driving resulted in unscheduled maintenance and failures that consisted of a variety of subsystem failures. A description of failures, and a complete and detailed listing of scheduled and unscheduled maintenance is provided in the Maintainability section of this report.
Accessibility, in general, was adequate, components covered in Section 1.3 (Repair and/or Replacement of Selected Subsystems) along with all other components encountered during testing, were found to be readily accessible and no restrictions were noted.
The Reliability section compiles failures that occurred during Structural Durability Testing. Breakdowns are classified according to subsystems. The data in this section are arranged so that those subsystems with more frequent problems are apparent. Problems are also listed by class as defined in Section 2. The test bus encountered no Class 1 failures. The one Class 2 failure (road call), was the result of a leaking transmission fluid line. Of the remaining fourteen reported failures, seven were Class 3 and seven were Class 4.
The Safety Test, (a double-lane change, obstacle avoidance test) was safely performed in both right-hand and left-hand directions up to a maximum test speed of 45 mph. The performance of the bus is illustrated by a speed vs. time plot. Acceleration and Gradeability Test data are provided in Section 4, Performance. The average time to obtain 50 mph was 33.61 seconds.
The Shakedown Test produced a maximum final loaded deflection of 0.160 inches under a distributed static load of 17,250 lbs. The test resulted in essentially no permanent deflection of the structure. The Distortion Test was completed with all subsystems, doors
escape mechanisms operating properly. Water leakage was observed during the test at the slide channel of the driver’s window and the top right of the handicap entrance door. .........
The Static Towing Test was performed using a target load (towing force) of 20,400 lbs. The front and rear 20° upward pulls were not performed due to interference with the bumpers. Both 20° downward pulls were completed with no damage or deformation observed. Deformation of the right tow-hook bracket was observed after the front 20° left pull, and deformation of the left tow-hook bracket was observed after the rear 20° left pull. Additional static tests were suspended due to the deformation from the 20° left pulls. The Dynamic Towing Test was performed by means of a front and rear lift tow. The towing interface was accomplished with a hydraulic lift wrecker. The bus was towed without incident and no damage resulted from the test. The Jacking and Hoisting Tests were also performed without incident. The bus was found to be stable on the jack stands, and the minimum jacking clearance observed with a tire deflated was 5.7 inches.
A Fuel Economy Test was run on simulated central business district, arterial, and commuter courses. The results were 4.08 mpg, 4.03 mpg, and 6.52 mpg respectively; with an overall average of 4.55 mpg.
A series of Interior and Exterior Noise Tests was performed. These data are listed in Section 7.1 and 7.2 respectively.