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 (April 2017):

In April, did not meet the Target; the actual being 2,820 miles. The overall number of breakdowns went up from 748 in March to 867 in April. The number of Engine system failures increased by 19%, that of HVAC system failures decreased by 11%, that of Cooling system failures decreased by 9% and that of Brake system failures increased by 11%. 


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