EXECUTIVE SUMMARY
BYD Motors Inc. submitted a model K7, electric-powered
23 seat (including the driver) 30-foot bus, for a 12 yr/500,000 mile STURAA
test. The odometer reading at he time of
delivery was 2,460 miles. Testing
started on February 26, 2016 and was completed on March 27, 2017. 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 17, 2016 and was
completed on January 17, 2017.
The interior of the bus is configured
with seating for 23 passengers including the driver. Free floor space will accommodate 18 standing
passengers resulting in a potential load of 41 persons. At 150 lbs per person, this load results in a
measured gross vehicle weight of 28,190 lbs.
The first segment of the Structural Durability Test was performed with
the bus loaded to a GVW of 28,190 lbs.
The middle segment was performed at a seated load weight of 25,770 lbs
and the final segment was performed at a curb weight of 21,880 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.
Effective January 1, 2010 the Federal
Transit Administration determined that the total number of simulated passengers
used for loading all test vehicles will be based on the full complement of
seats and free-floor space available for standing passengers (150 lbs per
passenger). The passenger loading used
for dynamic testing will not be reduced in order to comply with Gross Axle
Weight Ratings (GAWR’s) or the Gross Vehicle Weight Ratings (GVWR’s) declared
by the manufacturer. Cases where the
loading exceeds the GAWR and/or the GVWR will be noted accordingly. During the testing program, all test vehicles
transported or operated over public roadways will be loaded to comply with the
GAWR and GVWR specified by the manufacturer.
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. Of the two
Class 2 failures one occurred with an axle and one with the drive system. Of the remaining 21 reported failures 17 were
Class 3 and four 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 31.01
seconds. The Stopping Distance phase of
the Brake Test was completed with the following results; for the Uniform High
Friction Test average stopping distances were 29.41’ at 20 mph, 57.15’ at 30
mph, 96.22’ at 40 mph and 127.07’ at 45 mph.
The average stopping distance for the Uniform Low Friction Test was 31.01’. There was no deviation from the test lane
during the performance of the Stopping Distance phase. During the Stability phase of Brake Testing
the test bus experienced no deviation from the test lane. The Parking Brake phase was completed with
the test bus maintaining the parked position for the full five minute period
with no slip or roll observed in both the uphill and downhill positions.
The Shakedown Test produced a maximum
final loaded deflection of 0.049 inches with a permanent set ranging between -0.003
to 0.005 inches under a distributed static load of 15,375 lbs. The Distortion Test was completed with all
subsystems, doors and escape mechanisms operating properly. Water leakage was observed during the test
inside the upper rear corner of the engine compartment and inside the upper
rear compartment. All subsystems operated properly.
The Static Towing Test was performed
using a target load (towing force) of 26,256 lbs. All four front pulls were completed to the
full test load with no damage or deformation observed. 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 3.2 inches.
A Fuel Economy Test was run on simulated
central business district, arterial, and commuter courses. The results are available in Section 6.
A series of Interior and Exterior Noise
Tests was performed. These data are
listed in Section 7.1 and 7.2 respectively.
Number: |
1605 |
Model: |
K7 |
Manufacturer: |
BYD MOTORS, INC. |
Vin Number: |
4B9KDLA16G2038102 |
|