BLIND TRANSMISSION-
(See TRANSMITTING IN THE BLIND.)
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.
BLIND ZONE-
(See BLIND SPOT.)
BLOCKED-Phraseology used to indicate that a radio transmission has been distorted or interrupted due to multiple simultaneous radio transmissions.
BOUNDARY LIGHTS-
(See AIRPORT LIGHTING.)
BRAKING ACTION (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 READING.)
BRAKING ACTION ADVISORIES- When tower controllers have received runway braking action reports which include the terms “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.” 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 deviating aircraft.
BROADCAST-Transmission of information for which an acknowledgement is not expected.
(See ICAO term BROADCAST.)
BROADCAST [ICAO]- A transmission of informa-tion relating to air navigation that is not addressed to a specific station or stations.

C

CALCULATED LANDING TIME- A term that may be used in place of tentative or actual calculated landing time, whichever applies.
CALL FOR RELEASE- Wherein the overlying ARTCC requires a terminal facility to initiate verbal coordination to secure ARTCC approval for release of a departure into the en route environment.
CALL UP- Initial voice contact between a facility and an aircraft, using the identification of the unit being called and the unit initiating the call.
(Refer to AIM.)
CANADIAN MINIMUM NAVIGATION PERFOR-MANCE SPECIFICATION AIRSPACE-That portion of Canadian domestic airspace within which MNPS separation may be applied.
CARDINAL ALTITUDES-“Odd” or “Even” thousand‐foot altitudes or flight levels; e.g., 5,000, 6,000, 7,000, FL 250, FL 260, FL 270.
(See ALTITUDE.)
(See FLIGHT LEVEL.)
CARDINAL FLIGHT LEVELS-
(See CARDINAL ALTITUDES.)
CAT-
(See CLEAR‐AIR TURBULENCE.)