Pilot/Controller Glossary

HAA-
(See HEIGHT ABOVE AIRPORT.)

HAL-
(See HEIGHT ABOVE LANDING.)

HANDOFF- An action taken to transfer the radar
identification of an aircraft from one controller to
another if the aircraft will enter the receiving
controller"s airspace and radio communications with
the aircraft will be transferred.
HAR-
(See HIGH ALTITUDE REDESIGN.)

HAT-
(See HEIGHT ABOVE TOUCHDOWN.)

HAVE NUMBERS- Used by pilots to inform ATC
that they have received runway, wind, and altimeter
information only.
HAZARDOUS INFLIGHT WEATHER ADVISORY SERVICE (HIWAS)- Continuous recorded
hazardous inflight weather forecasts broadcasted to
airborne pilots over selected VOR outlets defined as
an HIWAS BROADCAST AREA.
HAZARDOUS WEATHER INFORMATION-
Summary of significant meteorological information
(SIGMET/WS), convective significant meteorological information (convective SIGMET/WST), urgent
pilot weather reports (urgent PIREP/UUA), center
weather advisories (CWA), airmen"s meteorological
information (AIRMET/WA) and any other weather
such as isolated thunderstorms that are rapidly
developing and increasing in intensity, or low
ceilings and visibilities that are becoming widespread which is considered significant and are not
included in a current hazardous weather advisory.
HEAVY (AIRCRAFT)-
(See AIRCRAFT CLASSES.)

HEIGHT ABOVE AIRPORT (HAA)- The height of
the Minimum Descent Altitude above the published
airport elevation. This is published in conjunction
with circling minimums.
(See MINIMUM DESCENT ALTITUDE.)

HEIGHT ABOVE LANDING (HAL)- The height
above a designated helicopter landing area used for
helicopter instrument approach procedures.
(Refer to 14 CFR Part 97.)

HEIGHT ABOVE TOUCHDOWN (HAT)- The
height of the Decision Height or Minimum Descent
Altitude above the highest runway elevation in the
touchdown zone (first 3,000 feet of the runway). HAT
is published on instrument approach charts in
conjunction with all straight-in minimums.
(See DECISION HEIGHT.)
(See MINIMUM DESCENT ALTITUDE.)

HELICOPTER- A heavier-than-air aircraft supported in flight chiefly by the reactions of the air on
one or more power-driven rotors on substantially
vertical axes.
HELIPAD- A small, designated area, usually with a
prepared surface, on a heliport, airport, landing/takeoff area, apron/ramp, or movement area used for
takeoff, landing, or parking of helicopters.
HELIPORT- An area of land, water, or structure used
or intended to be used for the landing and takeoff of
helicopters and includes its buildings and facilities if
any.
HELIPORT REFERENCE POINT (HRP)- The
geographic center of a heliport.
HERTZ- The standard radio equivalent of frequency
in cycles per second of an electromagnetic wave.
Kilohertz (kHz) is a frequency of one thousand cycles
per second. Megahertz (MHz) is a frequency of one
million cycles per second.
HF-
(See HIGH FREQUENCY.)

HF COMMUNICATIONS-
(See HIGH FREQUENCY COMMUNICATIONS.)

HIGH ALTITUDE REDESIGN (HAR)- A level of
non-restrictive routing (NRR) service for aircraft
that have all waypoints associated with the HAR
program in their flight management systems or
RNAV equipage.
HIGH FREQUENCY- The frequency band between
3 and 30 MHz.
(See HIGH FREQUENCY COMMUNICATIONS.)