CHAMPION BUS INC. Download PDF ReportEXECUTIVE SUMMARY
Champion Bus Inc., submitted a model EZ Trans, diesel-powered 25 seat (including the driver) 28-foot bus, for a 7 yr/200,000 mile STURAA test. The test bus is built on a Chevrolet Kodiak Series 5500 chassis. The odometer reading at the time of delivery was 8,100 miles. Testing started on January 16, 2004 and was completed on August 31, 2004. 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 was started on March 30, 2004 and was completed on August 23, 2004.
The interior of the bus is configured with seating for 25 passengers including the driver. Free floor space will accommodate 12 standing passengers resulting in a potential capacity of 37 persons. At 150 lbs per person, this load results in a measured gross vehicle weight of 20,140 lbs. In order to avoid exceeding the GAWR (13,500 lbs) of the rear axle, ballast for 6 standing passengers was eliminated. This reduction from full capacity resulted in an adjusted measured gross vehicle weight of 19,150 lbs and was used for all dynamic testing. The middle segment was performed at a SLW of 18,220 lbs and the final segment was performed at a CW of 14,620 lbs. Durability driving resulted in unscheduled maintenance and failures that involved a variety of subsystems. 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. The problems are also listed by class as defined in Section 2. The test bus encountered no Class 1 failures. The one class 2 failure was the result of a cracked transmission housing. Of the other 41 reported failures, 26 were Class 3 and 15 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 21.08 seconds.
The Shakedown Test produced a maximum final loaded deflection of 0.161 inches with a permanent set ranging between –0.006 to 0.004 inches under a distributed static load of 13,875 lbs. The Distortion Test was completed with all
subsystems, doors and escape mechanisms operating properly. Water leakage was observed during the test at the upper seal of the driver’s door.
The test bus submitted for testing was not equipped with any type of tow eyes or tow hooks, therefore, the Static Towing Test was not performed. The Dynamic Towing Test was performed by means of a front-lift tow. The towing interface was accomplished using a hydraulic under-lift wrecker. The bus was towed without incident and no damage resulted from the test. The manufacturer does not recommend towing the bus from the rear, therefore, a rear test was not performed. 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 4.5 inches.
A Fuel Economy Test was run on simulated central business district, arterial, and commuter courses. The results were 6.27 mpg, 6.45 mpg, and 9.51 mpg respectively; with an overall average of 7.01 mpg.
A series of Interior and Exterior Noise Tests was performed. These data are listed in Section 7.1 and 7.2 respectively.