EXECUTIVE SUMMARY
Alexander Dennis, LTD., UK submitted a
model E500, diesel-powered 87 seat (including the driver) 43-foot long, and 13-foot
6-inch high double decker bus, for a 12 yr./500,000 mile STURAA test. Testing started on October 16, 2014 and was
completed on May 4, 2015. 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 October 16, 2014 and was
completed on May 1, 2015.
The interior of the bus is configured
with seating for 87 passengers including the driver. Free floor space on the lower saloon will
accommodate 20 standing passengers resulting in a potential load of 107
persons. Note: the upper saloon is not
designed to accommodate standing passengers.
At 150 lbs. per person, this load results in a measured gross vehicle
weight of 52,940 lbs. The first segment
of the Structural Durability Test was performed with the bus loaded to a GVW of
52,940 lbs. The middle segment was
performed at a seated load weight of 49,620 lbs. and the final segment was
performed at a curb weight of 36,450 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 or Class 2 failures. Of the 35 reported failures, 20 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 33.07 seconds. Top speed obtained on the dynamometer was 67
mph. The Stopping Distance phase of the
Brake Test was completed with the following results; for the Uniform High
Friction Test average stopping distances were 28.51’ at 20 mph, 62.54’ at 30
mph, 107.76’ at 40 mph and 137.72’ at 45 mph.
The average stopping distance for the Uniform Low Friction Test was 32.18’. 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 but did experience
pull to the left during both approaches to the Split Friction Road
surface. 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 0.205 inches with a permanent set ranging between -0.003
to 0.004 inches under a distributed static load of 39,075 lbs. The Distortion Test was completed with all
subsystems, doors and escape mechanisms operating properly. Water leakage was observed during the test at
the top right corner of the windshield.
The Static Towing Test was performed
using a target load (towing force) of 43,740 lbs. The 20° upward and 20° downward pulls were completed to the
full target test load of 43,740 lbs. (1.2 X CW 36,450 lbs.) with no damage or
deformation observed. After completion
and reaching the full target test load of the 20° left pull, deformation to the
left of the right side tow eye was observed.
Further testing was terminated. 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 3.4 inches.
A Fuel Economy Test was run on
simulated central business district, arterial, and commuter courses. The results were 2.87 mpg, 3.16 mpg, and 5.79
mpg respectively; with an overall average of 3.46 mpg.
A series of Interior and Exterior
Noise Tests was performed. These data
are listed in Section 7.1 and 7.2 respectively.
The Emissions Test was performed. These results are available in Section 8 of
this report.
Number: |
1411 |
Model: |
E500 |
Manufacturer: |
ALEXANDER DENNIS INC. |
Vin Number: |
SFET9K748EGN13484 |
|