The HFD's helicopter is known as Air-1.  Air-1 flies day and night visual flight rules (VFR) missions and is often dispatched to emergencies with the HFD Rescue Squad.  For example, Rescue Squad members will sometimes rappel from Air-1 into a remote, mountainous area to locate a lost or injured hiker.  This method allows Rescue Squad members to quickly reach and provide aid to the hiker, whereas having the Rescue Squad follow a trail to the hiker may require several hours.   

The HFD has two McDonnell-Douglas MD 520N No Tail Rotor (NOTAR^®) helicopters.  The second helicopter is designated as Air-2.  Air-1 and Air-2 alternate duty, enabling at least one helicopter to be available for emergencies if the other is down for maintenance or repairs.  Occasionally, both helicopters will be dispatched to emergencies.  Air-1 and Air-2 are on duty 24 hours a day, 7 days a week.  HFD helicopters respond to emergencies on Oahu, including the ocean up to three miles offshore.  Although helicopter operations are expensive, the HFD does not charge the public for rescue services.      

The most distinguishing feature of these helicopters is the lack of a conventional tail rotor.  NOTAR^® helicopters provide improved safety and reduced noise when compared to helicopters with conventional tail rotors.  These safety features are important during both flight and ground operations.  Anti-torque in NOTAR^® helicopters is controlled by low pressure, high volume air forced through the end of the tail boom.  The air is propelled by a variable pitch fan enclosed in the aft fuselage section of the helicopter.  The fan is driven from the main rotor transmission.