Aeronautical Terms beginning with B
Back Side Of The Power Curve
Flight regime in which flight at a higher airspeed requires a lower power setting and a lower airspeed requires a higher power setting in order to maintain altitude.
Balked Landing
A go-around.
Ballast
Removable or permanently installed weight in an aircraft used to bring the center of gravity into the allowable range.
Balloon
The result of a too aggressive flare during landing causing the aircraft to climb.
Basic Empty Weight (Gama)
Basic empty weight includes the standard empty weight plus optional and special equipment that has been installed.
Best Angle Of Climb (Vx)
The speed at which the aircraft will produce the most gain in altitude in a given distance.
Best Glide
The airspeed in which the aircraft glides the furthest for the least altitude lost when in non-powered flight.
Best Rate Of Climb (Vy)
The speed at which the aircraft will produce the most gain in altitude in the least amount of time.
Blade Face
The flat portion of a propeller blade, resembling the bottom portion of an airfoil.
Bleed Air
Compressed air tapped from the compressor stages of a turbine engine by use of ducts and tubing. Bleed air can be used for deice, anti-ice, cabin pressurization, heating, and cooling systems.
Bleed Valve
In a turbine engine, a flapper valve, a popoff valve, or a bleed band designed to bleed off a portion of the compressor air to the atmosphere. Used to maintain blade angle of attack and provide stall-free engine acceleration and deceleration.
Boost Pump
An electrically driven fuel pump, usually of the centrifugal type, located in one of the fuel tanks. It is used to provide fuel to the engine for starting and providing fuel pressure in the event of failure of the engine driven pump. It also pressurizes the fuel lines to prevent vapor lock.
Buffeting
The beating of an aerodynamic structure or surface by unsteady flow, gusts, etc.; the irregular shaking or oscillation of a vehicle component owing to turbulent air or separated flow.
Bus Bar
An electrical power distribution point to which several circuits may be connected. It is often a solid metal strip having a number of terminals installed on it.
Bus Tie
A switch that connects two or more bus bars. It is usually used when one generator fails and power is lost to its bus. By closing the switch, the operating generator powers both busses.
Bypass Air
The part of a turbofan’s induction air that bypasses the engine core.
Bypass Ratio
The ratio of the mass airflow in pounds per second through the fan section of a turbofan engine to the mass airflow that passes through the gas generator portion of the engine. Or, the ratio between fan mass airflow (lb/sec.) and core engine mass airflow (lb/sec.).
Back course (BC)
The reciprocal of the localizer course for an ILS. When flying a back-course approach, an aircraft approaches the instrument runway from the end at which the localizer antennas are installed.
Baro-aiding
A method of augmenting the GPS integrity solution by using a non-satellite input source. To ensure that baro-aiding is available, the current altimeter setting must be entered as described in the operating manual.
Barometric scale
A scale on the dial of an altimeter to which the pilot sets the barometric pressure level from which the altitude shown by the pointers is measured.
BC
See back course.
Block altitude
A block of altitudes assigned by ATC to allow altitude deviations; for example, Maintain block altitude 9 to 11 thousand. Cage. The black markings on the ball instrument indicating its neutral position.
Basic need
A perception factor that describes a person’s ability to maintain and enhance the organized self.
Behaviorism
Theory of learning that stresses the importance of having a particular form of behavior reinforced by someone other than the student to shape or control what is learned.
Bookmark
A means of saving addresses on the World Wide Web (WWW) for easy future access. Usually done by selecting a button on the web browser screen, it saves the current web address so it does not have to be input again in a lengthy series of characters.
Branching
A programming technique which allows users of interactive video, multimedia courseware, or online training to choose from several courses of action in moving from one sequence to another.
Briefing
An oral presentation where the speaker presents a concise array of facts without inclusion of extensive supporting material.
Building block concept
Concept of learning that new knowledge and skills are best based on a solid foundation of previous experience and/or old learning. As knowledge and skills increase, the base expands, supporting further learning.
Balance Tab
An auxiliary control mounted on a primary control surface, which automatically moves in the direction opposite the primary control to provide an aerodynamic assist in the movement of the control. Sometimes referred to as a servo tab.
Basic Empty Weight (Gama)
Basic empty weight includes the standard empty weight plus optional and special equipment that has been installed.
Bernoulli’s Principle
A principle that explains how the pressure of a moving fluid varies with its speed of motion. An increase in the speed of movement causes a decrease in the fluid’s pressure.
Biplanes
Airplanes with two sets of wings.
Bypass Ratio
The ratio of the mass airflow in pounds per second through the fan section of a turbofan engine to the mass airflow that passes through the gas generator portion of the engine.