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|What instrument measures the weight of air?
|What is the standard atmospheric pressure at sea level measured in inches of mercury? In psi?
|29.92 inches of mercury; 14.7 psi.
|What are the two temperature scales that are commonly used?
|Fahrenheit and Celsius.
|If two aircraft are flying with the same horsepower but at different altitudes, why does the aircraft flying at higher altitudes fly faster than the aircraft flying at a lower altitude?
|Because at the higher altitude, the air is less dense therefore causing less drag on the aircraft.
|What is the term for the curve of the surface of an airfoil from the leading edge to the trailing edge?
|What aerodynamic forces affect aircraft in flight?
|Life, weight, thrust, and drag.
|How does drag act in relation to relative wind?
|The angle between the mean chord line of an airfoil and the aircraft flight path.
|How are airframe components joined?
|By rivets, bolts, screws, welds or adhesives.
|What are the five stresses to which airframes are subjected?
|Tension, compression, torsion, shear, and bending.
|Which fuselage design does not use formers, frame assemblies, or bulkheads to give shape to the fuselage?
|The monocoque design.
|What internal wing components serve as an attachment point for the skin?
|The ribs and stringers.
|What type of material is usually used for construction of flight control surfaces?
|What is used to round out the angle formed btween the fixed tail surfaces and the fuselage?
|What structural unit provides a smooth airflow around and into the engine inlet?
|What component controls airflow around the weapons to reduce turbulence in the bay on some bomber aircraft?
|Bay spoilers or air spoilers.
|How do doors differ from panels?
|Doors are hinged.
|Most transparent structures on an aircraft, such as canopies, windshields, and windows are made of what two materials?
|Transparent plastics or safety glass.
|How do paint removes and stripping compounds affect the plastic facings of the radome?
|It may adversely affect its electrical properties or strength.
|How are fuselage station numbers measured?
|In inches from the reference datum or zero point on or near the aircraft nose.
|What are the three axes that an aircraft operates around?
|Vertical, lateral, and longitudinal.
|What are the lateral control surface of the aircraft
|Ailerons, spoilers/speed brakes, and wing flaps.
|What controls all directional movements of the aircraft?
|Primary flight controls.
|What primary flight control guides the aircraft about the vertical axis?
|Which type of stabilator has both sides connected together so that when one side moves the other side must move in the same direction and amount?
|What is an elevon?
|It is a combination of an aileron and an elevator.
|What are five types of wing flaps?
|Plain, split, fowler, slatted, and leading edge slats or flaps.
|What is the difference between leading-edge flaps and wing slats?
|If the leading edge operates in conjunction with the trailing edge flaps, then you have leading-edge flaps. If they operate independently of the flaps, they are called slats.
|What is the purpose of the speed brakes?
|Increase drag to slow the aircraft and/or reduce landing distance.
|List the three types of trim systems.
|Roll, Pitch, and Yaw.
|Which type of flight control system reduces the need for long cables, turnbuckles, quick disconnects, push-pull rods, and the associated flight control hardware?
|What are the two major parts of the AFCS?
|Stab aug system and the A/P system.
|What system is used to make bomber aircraft stable for launching weapons?
|What auto pilot system mode automatically maintains aircraft speed?
|A class of physical phenomena arising from the existence and interactions of electric charges.
|Of what particles are atoms composed?
|Neutrons, protons, and electrons.
|List four examples of insulators.
|Glass, wood, rubber, and plastic
|List four examples of conductors.
|Gold, copper, platinum, and silver.
|Where do you normally use semiconductors?
|In solid state devices.
|What is EMF?
|Electromagnetic force: the electrical pressure that causes electrons to flow through the conductor.
|Define electrical current.
|The movement of electrons through a conductor.
|What factors affect the amount of resistance in a conductor?
|The type of material used, temperature, size.
|What unit of measurement is used to express electrical power?
|What is a simple definition of magnetism?
|The ability of a substance to attract.
|How are artificial magnets classified?
|Permanent or temporary.
|What is permeability?
|The ease of ability to conduct magnetic lines of force.
|What is residual magnetism?
|The amount of magnetism that remains in a temporary magnet.
|How is magnetism induced in magnetic material?
|Place in a magnetic field or bring it into contact with another magnet.
|Can magnetic lines of force be insulated?
|What are the three most commonly used shapes of magnets?
|Bar, ring, or horseshoe.
|How can a magnet be weakened?
|Heating or excessive jarring.
|A term for magnetic lines of force.
|How is electromagnetism developed?
|By current of electricity.
|When current flows through a conductor, does a magnetic field exist?
|What must you know to apply the "left hand rule"?
|The direction of the current flow.
|What rule do you use to determine the flux direction of a wire in a loop?
|The left hand rule.
|How can an electromagnet's field strength be increased?
|By using a few terms of wire carrying a larger current or using many terms of wire carrying a small current.
|What is the purpose of conductor?
|Provide a path for electrons to flow with minimum resistance.
|Why are protective devices installed in aircraft electrical systems?
|Protect against system overloads and shorts in a circuit.
|How much time must pass before resetting a trip-free type circuit breaker?
|After a cooling-off period of approximately 1 minute.
|What is the purpose of a current limiter?
|Provide protection against fault currents.
|What is the purpose of a resistor?
|Control the amount of correct flow in a circuit.
|Why is alternating current used as the primary electrical power source in aircraft?
|Less power is lost during transmission and the elimination of insulation and brushes.
|What is the unit of measurement for frequency?
|Define phase relationship.
|A condition in which two moving objects are changing in, or out of, step..
|What are the two classifications of AC generation systems?
|Variable-frequency and constant-frequency.
|What frequency is used for AC power generation on aircraft?
|How is voltage induced in a brush-type generator?
|DC from an integral exciter generator is passed through windings of the rotor.
|What are the three generators that make up a brushless AC generator?
|A permanent magnet generator, an AC exciter generator, and the main AC generator.
|What weak point was eliminated by the design of a brushless-type generator?
|Arcing (which more easily occurs in rarefied air).
|What are the two main components of an AC generator?
|Rotor assembly and stator.
|What three components make up the stator?
|PMG armature, exciter field, and main armature windings.
|What are the two functions of the CSD governor system?
|To control the drive output speed and equalize the load between generators operating in parallel.
|If CSD output rotation drives the generator below 365 Hz, what component removes the generator from the bus?
|If the CSD temperature rises to an overheat condition, what should be done to prevent further damage?
|Disconnect the CSD.
|What is installed on most IDGs to provide for easier installation and removal?
|A quick attach-detach clamp.
|What are the typical functions of a GCU?
|Voltage regulation, frequency, and load control, real and reactive load division, over/under protection.
|How is voltage regulation and current limiting accomplished in the GCU?
|By varying the generator excitation field.
|How does the frequency and load controller for each generator system regulate the frequency of the generator CSD?
|By controlling the magnetic trim head governor on the CSD.
|What are the internal components of a battery?
|Plates, separators, and electrolytes.
|What are the primary causes of premature failure of a lead-acid battery?
|Abuse, overcharge, low solution, undercharge, and mountings.
|What is the fundamental unit of the nickel-cadmium battery?
|How are nickel-cadmium constructed?
|By inserting positive and negative plates in plastic cases with nylon and cellophane separators.
|When does nickel-cadmium battery's electrolyte reach its maximum level?
|When the battery is fully charged.
|How are motors classified?
|By voltage, current used (AC or DC), and methods of motor excitation.
|How can the direction of rotation for a series motor be changed?
|By reusing the current flow in a field winding or reusing current flow in armature.
|What advantage does the series motor have over other types of motors?
|It operates on AC or DC excitation.
|How is the field winding of a shunt motor connected with the armature?
|What type of T-R is used to a nickel-cadmium battery in many aircraft?
|What is another name for a T-R?
|Any substance that occupies space.
|Since liquids and gases have many properties in common, how are they frequently classified?
|All matter is made up of what?
|Which matter has the property of resisting changes in shape when a force is applied?
|When sufficient force to a solid causes distortion, the solid is said to have exceeded what?
|Its elastic limit.
|Which factors affect the amount of expansion and contraction in a solid?
|The amount of temperature change and the expansion characteristic of the solid.
|What are the most outstanding characteristics of a solid?
|The Its ability to conform to the shape of its containing vessel and that it has a face surface.
|For a liquid to transmit a pushing force, what condition must exist first?
|It must be completely enclosed in a container.
|What would cause a cylinder of air to increase in pressure when placed in the sun?
|The air (gas) expands as its temperature increases, and since it is confined by the cylinder, its pressure will increase.
|What is one of the main differences in the characteristics of gases when compared to liquids?
|Gases are compressible while liquids are not.
|State the basic principle of Pascal's Law.
|When a fluid is confined and force is applied, this force(pressure) is transmitted equally to all points in the system.
|Under what conditions does Pascal's Law not apply to fluids?
|When fluids are in motion.
|State the basic principle of Boyle's Law.
|If the pressure on a confined gas varies, its volume will vary inversely in the same proportion as long as the temperature does not change.
|Using Charles's Law, explain the effect of heating a gas in a cylinder that has a movable piston.
|Heating a confined gas will cause an expansion (volume increase) in direct proportion to its temperature change, thus causing the piston to move.
|What is another name for the Boyle's-Charles law?
|General gas law.
|What is the mechanical advantage ratio if a 60-pound force is used to raise a 240-pound weight?
|What is the mechanical advantage ratio if a 3-pound force is used to raise 99 pounds?
|A 150-pound weight is placed on a 10-square inch piston and is then lifted by a force applied to a 2-square-inch piston. What force is required on the small piston, and what is the mechanical advantage?
|30 pounds of force, 5:1
|A 20-pound force on a 3-square-inch piston can lift how much weight on a 12-square-inch piston? What is the mechanical advantage?
|80 pounds of force, 4:1
|What is the pressure on a surface 12 square inches in area and supporting a weight of 216 pounds.
|How far will an 8-square-inch piston move if a 2-square-inch piston moves 8 inches?
|What characteristic of a fluid determines its resistance to flow?
|What effect does an orifice have on fluid-flow when compared to a venturi?
|An orifice will cause more turbulence and thus more energy loss than a venturi because it is not steamlined.
|How can resistance to flow be reduced?
|By streamlining the flow.
|What pressure difference can be observed during fluid-flow through a venturi?
|There is a pressure drop at the narrow opening (throat) of a venturi as the rate of flow of the fluid increases at this point. The pressure will increase again after passing through the throat.
|How much fluid should a reservoir hold?