term used by air traffic controllers to taxi an aircraft on the runway opposite
to the traffic flow. The aircraft may be instructed to back-taxi to the
beginning of the runway or at some point before reaching the runway end for the
purpose of departure or to exit the runway.
(See TRAFFIC PATTERN.)
(See AERONAUTICAL BEACON.)
(See AIRPORT ROTATING
(See AIRWAY BEACON.)
(See MARKER BEACON.)
(See NONDIRECTIONAL BEACON.)
BEARING- The horizontal
direction to or from any point, usually measured clockwise from true north,
magnetic north, or some other reference point through 360 degrees.
(See NONDIRECTIONAL BEACON.)
BELOW MINIMUMS- Weather
conditions below the minimums prescribed by regulation for the particular action
involved; e.g., landing minimums, takeoff minimums.
BLAST FENCE- A barrier
that is used to divert or dissipate jet or propeller blast.
BLAST PAD- A surface
adjacent to the ends of a runway provided to reduce the erosive effect of jet
blast and propeller wash.
BLIND SPEED- The rate of
departure or closing of a target relative to the radar antenna at which
cancellation of the primary radar target by moving target indicator (MTI)
circuits in the radar equipment causes a reduction or complete loss of signal.
(See ICAO term BLIND
BLIND SPOT- An area from
which radio transmissions and/or radar echoes cannot be received. The term is
also used to describe portions of the airport not visible from the control
(See TRANSMITTING IN THE
BLIND VELOCITY [ICAO]- The
radial velocity of a moving target such that the target is not seen on primary
radars fitted with certain forms of fixed echo suppression.
(See BLIND SPOT.)
Phraseology used to indicate that a radio transmission has been distorted or
interrupted due to multiple simultaneous radio transmissions.
BOTTOM ALTITUDE– In reference to published
altitude restrictions on a STAR or STAR runway
transition, the lowest altitude authorized.
(See AIRPORT LIGHTING.)
(GOOD, FAIR, POOR, OR NIL)- A report of conditions on the airport
movement area providing a pilot with a degree/quality of braking that he/she
might expect. Braking action is reported in terms of good, fair, poor, or nil.
(See RUNWAY CONDITION
BRAKING ACTION ADVISORIES-
When tower controllers have received runway braking action reports which include
the terms “fair,” “poor,” or “nil,” or whenever weather conditions are conducive
to deteriorating or rapidly changing runway braking conditions, the tower will
include on the ATIS broadcast the statement, “Braking action advisories are in
effect” on the ATIS broadcast. During the time braking action advisories are in
effect, ATC will issue the latest braking action report for the runway in use to
each arriving and departing aircraft. Pilots should be prepared for
deteriorating braking conditions and should request current runway condition
information if not volunteered by controllers. Pilots should also be prepared to
provide a descriptive runway condition report to controllers after landing.
BREAKOUT- A technique to
direct aircraft out of the approach stream. In the context of close parallel
operations, a breakout is used to direct threatened aircraft away from a
BROADCAST- Transmission of
information for which an acknowledgement is not expected.
(See ICAO term BROADCAST.)
BROADCAST [ICAO]- A
transmission of information relating to air navigation that is not addressed to
a specific station or stations.