Key Performance Indicators

Bus Mean Distance Between Failures

Definition: An industry standard that measures the mechanical reliability of the fleet. It measures the average bus miles between National Transit Database (NTD) reportable mechanical failures i.e., incidents precluding a revenue vehicle from completing its trip, or starting its next scheduled trip. Currently, all mechanical breakdowns are counted as failures, thus exceeding the number of failures reported to NTD. 

Performance (November 2016):

In November, did not meet the Target; the actual being 3,742 miles. The overall number of breakdowns decreased from 666 in October to 618 in November. The number of Engine System failures decreased by 3%, that of HVAC failures decreased by 39%, that of Cooling System failures decreased by 4% and that of Brake System failures increased by 4%. 


  1. Continue troubleshooting refresher training at all garages
  2. Replace coolant sensors and defroster valves on selected bus models