Glossary >> H
HAA -- HZ
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.
HAT- (See HEIGHT ABOVE TOUCHDOWN.)
HAVE NUMBERS- Used by pilots to inform ATC that
they have received runway, wind, and altimeter information
HAZARDOUS INFLIGHT WEATHER ADVISORY SERVICE- 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- 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- The height above a designated
helicopter landing area used for helicopter instrument
(Refer to FAR Part 97.)
HEIGHT ABOVE TOUCHDOWN- 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
(See DECISION HEIGHT.)
(See MINIMUM DESCENT ALTITUDE.)
HELICOPTER- Rotorcraft that, for its horizontal
motion, depends principally on its engine-driven
(See ICAO term HELICOPTER.)
HELICOPTER [ICAO]- A heavier-than-air aircraft supported
in flight chiefly by the reactions of the air on
one or more power-driven rotors on substantially
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
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 FREQUENCY- The frequency band between 3 and
(See HIGH FREQUENCY COMMUNICATIONS.)
HIGH FREQUENCY COMMUNICATIONS- High radio frequencies
(HF) between 3 and 30 MHz used for air-to-ground
voice communication in overseas operations.
HIGH SPEED EXIT- (See HIGH SPEED TAXIWAY.)
HIGH SPEED TAXIWAY- A long radius taxiway designed
and provided with lighting or marking to define
the path of aircraft, traveling at high speed (up
to 60 knots), from the runway center to a point
on the center of a taxiway. Also referred to as
long radius exit or turn-off taxiway. The high speed
taxiway is designed to expedite aircraft turning
off the runway after landing, thus reducing runway
HIGH SPEED TURNOFF- (See HIGH SPEED TAXIWAY.)
HIWAS- (See HAZARDOUS INFLIGHT WEATHER ADVISORY
HIWAS AREA- (See HAZARDOUS INFLIGHT WEATHER ADVISORY
HIWAS BROADCAST AREA- A geographical area of responsibility
including one or more HIWAS outlet areas assigned
to an AFSS/FSS for hazardous weather advisory broadcasting.
HIWAS OUTLET AREA- An area defined as a 150 NM radius
of a HIWAS outlet, expanded as necessary to provide
HOLDING PROCEDURE- (See HOLD PROCEDURE.)
HOLD PROCEDURE- A predetermined maneuver which keeps
aircraft within a specified airspace while awaiting
further clearance from air traffic control. Also
used during ground operations to keep aircraft within
a specified area or at a specified point while awaiting
further clearance from air traffic control.
(See HOLDING FIX.)
(Refer to AIM.)
HOLD-SHORT POINT- A point on the runway beyond which
a landing aircraft with a LAHSO clearance is not
authorized to proceed. This point may be located
prior to an intersecting runway, taxiway, predetermined
point, or approach/departure flight path.
HOLDING FIX- A specified fix identifiable to a pilot
by NAVAID's or visual reference to the ground used
as a reference point in establishing and maintaining
the position of an aircraft while holding.
(See VISUAL HOLDING.)
(Refer to AIM.)
HOLDING POINT [ICAO]- A specified location, identified
by visual or other means, in the vicinity of which
the position of an aircraft in flight is maintained
in accordance with air traffic control clearances.
HOLD FOR RELEASE- Used by ATC to delay an aircraft
for traffic management reasons; i.e., weather, traffic
volume, etc. Hold for release instructions (including
departure delay information) are used to inform
a pilot or a controller (either directly or through
an authorized relay) that an IFR departure clearance
is not valid until a release time or additional
instructions have been received.
(See ICAO term HOLDING POINT.)
HOLD-SHORT POSITION MARKING- The painted runway
marking located at the hold-short point on all LAHSO
HOLD-SHORT POSITION LIGHTS- Flashing in-pavement
white lights located at specified hold-short points.
HOLD-SHORT POSITION SIGNS- Red and white holding
position signs located alongside the hold-short
HOMING- Flight toward a NAVAID, without correcting
for wind, by adjusting the aircraft heading to maintain
a relative bearing of zero degrees.
(See ICAO term HOMING.)
HOMING [ICAO]- The procedure of using the direction-finding
equipment of one radio station with the emission
of another radio station, where at least one of
the stations is mobile, and whereby the mobile station
proceeds continuously towards the other station.
HOVER CHECK- Used to describe when a helicopter/VTOL
aircraft requires a stabilized hover to conduct
a performance/power check prior to hover taxi, air
taxi, or takeoff. Altitude of the hover will vary
based on the purpose of the check.
HOVER TAXI- Used to describe a helicopter/VTOL aircraft
movement conducted above the surface and in ground
effect at airspeeds less than approximately 20 knots.
The actual height may vary, and some helicopters
may require hover taxi above 25 feet AGL to reduce
ground effect turbulence or provide clearance for
(See AIR TAXI.)
(See HOVER CHECK.)
(Refer to AIM.)
HOW DO YOU HEAR ME?- A question relating to the
quality of the transmission or to determine how
well the transmission is being received.
HZ- (See HERTZ.)
Pilot Glossary >> H