The test vehicle is programmed for a controlled aircraft wander simulation and can operate in manual or fully automatic modes and capable of a speed of up to 15 miles per hour. The maximum speed however, has been limited (hard coded) to 5 miles per hour.
The test vehicle is comprised of two carriages that can
accommodate up to five load modules each. Each load module has two
wheels. This allows for configurations of up to 20 wheels with loads up to
75,000 pounds (333.75 kN) per wheel.
The north carriage is designated "Carriage 1", the south carriage is designated "Carriage 2". The east-most load module on each of the carriages is numbered "1"; the west-most load module on each of the carriages is numbered "5". Therefore, load module 1-1 is on the north carriage and faces the east end of the facility. Similarly, load module 2-5 is on the south carriage and faces the west end of the facility. Inner wheels are desinated as "A" and outer wheels as "B". Each of the load modules can be operated independently to simulate 1, 2, 4, 5, 6, 8, or 10 wheel loads per carriage.
Duel wheel spacing on each of the modules can be adjusted with axle replacements. Tandem spacing of the modules can be set by using different lateral mounting positions on the carriage. Simulation of a single wheel load requires the installation of a single wheel module.
During construction cycles 1 and 3, only 2-wheel modules were installed. Specific wheel load configurations are published under each construction/traffic testing cycle.
Vehicle
Wander. The pavement test vehicle simulates realistic aircraft wander by
varying the lateral (y) position of the carriages to simulate a normal
distribution of aircraft traffic during traffic testing. The wander
pattern used for the majority of the traffic testing consists of 66
vehicle passes, arranged in 9 wander positions (or tracks). The wander
positions and sequences were chosen to simulate a normal distribution of
aircraft traffic with a standard deviation of 30.5 inches (representing
the current design condition for airport taxiways). Normally, the same
wander is used on both carriages and it is changed at one end of the
test pavement. Specific wander patterns are published under each
construction/traffic testing cycle.