AIRPORT PLANNING MANUAL 5.7. PRECONDITIONEDAIRFLOWREQUIREMENTS This subsection presents the following information: • The air conditioning requirements for heating and cooling using ground conditioned air. The curves show airflow requirements to heat or cool the aircraft at ambient conditions within a given time. • The air conditioning heating and cooling requirements to maintain a constant cabin air temperature using low-pressure conditioned air. This conditioned air is supplied through a ground air connection directly to the passenger cabin, bypassing the air cycle machines. EFFECTIVITY: ALL Section 5 Page 5-11 Oct 06/11 w-apm1346