Star Trans by Supreme Corp. Download PDF Report
Startrans, a Supreme Corp. Company submitted a model President Low Floor 30’, diesel-powered 25 seat (including the driver) 31-foot bus, for a 10 yr/350,000 mile STURAA test. The odometer reading at the time of delivery was 12,727 miles. Testing started on November 2, 2007 and was completed on May 14, 2009. 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 November 29, 2007 and was completed on April 21, 2009.
The interior of the bus is configured with seating for 25 passengers including the driver. Free floor space will accommodate 15 standing passengers resulting in a potential load of 40 persons. At 150 lbs per person, this load results in a measured gross vehicle weight of 22,490 lbs. In order to avoid exceeding the GAWR (9,000 lbs) of the front axle and (12,000 lbs) of the rear axle, ballast for all 15 standing passengers was eliminated. This reduction from full capacity resulted in an adjusted measured gross vehicle weight of 20,270 lbs and was used for all dynamic testing. The first segment of the Structural Durability Test was performed at 20,270 lbs. The middle SLW segment was performed at the same 20,270 lbs and the final segment was performed at a CW of 16,580 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 or Class 2 failures. Of the fifty-seven reported failures, thirty-five were Class 3 and twenty-two 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 28.64 seconds.
The Shakedown Test produced a maximum final loaded deflection of 0285 inches with a permanent set ranging between 0.000 to 0.006 inches under a distributedstatic load of 15,000 lbs. The Distortion Test was completed with all subsystems, doors and escape mechanisms operating properly. Water leakage was observed throughout the test at the driver’s side of the windshield.
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 4.0 inches.
A Fuel Economy Test was run on simulated central business district, arterial, and commuter courses. The results were 4.82 mpg, 5.03 mpg, and 9.90 mpg respectively; with an overall average of 5.72 mpg.
A series of Interior and Exterior Noise Tests was performed. These data are listed in Section 7.1 and 7.2 respectively.