Global conglomerate Honeywell has inked a long-term pact with Tata Group-owned Air India for the maintenance of the Auxiliary Power Units (APUs) for the airline’s existing and new aircraft fleet. The pact for the aftermarket support to Honeywell APUs will help the airline reduce unplanned maintenance costs and downtime and, in turn, ensure high aircraft despatch and fleet availability. The APU is a critical piece of aircraft equipment that provides electrical power and air conditioning to a plane while it is on the ground. It helps ensure comfort and supplies the air source before a pilot is ready to start the main engines. Air India currently has over 300 aircraft, including its legacy fleet, which consists of over 100 Airbus A320, 15 Boeing B777 and its new fleet of 190 B737-8 aircraft, said a report.