Bakers School of Aeronautics Oral prep
12 cells. Each rated at 2 volts.
A 24 volt lead-acid battery has how many cells?
No, fumes from lead acid battery can contaminate the Nickel cadmium battery.
Can you store Ni-cad and Lead-acid batteries together?
dimension given for the space between parts
Define "clearance" as used in aircraft drawings.
the difference between the plus and minus allowable dimension.
Define "tolerance" as used in aircraft drawings.
makes it impossible to manually hold the circuit closed when excessive current is flowing.
Describe a no-trip circuit breaker (trip free).
Its a heavy object to determine the location of a spot directly below where its hanging from.
Describe a plumb bob?
coated with special corrosion resistant paint
How are battery compartments protected against corrosion?
Dimension lines are solid and usually broken at the midpoint for the insertion of measurement.
How are dimension lines shown on aircraft drawings?
AN colored either blue or black, 37° flare cone, small shoulder between threads AC gray or yellow, 35° flare cone, completely threaded to cone
How are standard AN type and AC type fluid line fittings identified?
revision letter (a, b, c, d, etc)
How can a change to an aircraft drawing be identified?
by the inside diameter, 1/16ths inch diameter
How is flexible hose sized?
By outside diameter measured in 1/16th of an inch and wall thickness.
How is metal tubing sized?
3 views. front, top and right side.
How many views are required to determine the shape of an object?
By drawing a detailed view at a larger scale.
How may an aircraft drawing of a part be drawn to bring out pertinent details?
By the color bands on the resistor.
How may the color bands of a fixed resistor be determined?
5-8% of the total hose length
How much slack must be left in a flexible hose during installation?
Every 24 inches
How often should flexible hoses be clamped in place?
Level the aircraft as per Type certificate data sheet, drain the fuel until empty. leaving the unusable fuel.
How should aircraft fuel be drained for weight and balance?
Level as per specified in tupe certificate data sheet
How should an aircraft be leveled for weighing during a weight and balance?
If records are up to date, basic weight and balance calculations are used.
How will you determine if a part will affect the C.G without weighing the aircraft?
By adding weight.
How would a negative moment be obtained?
Re-weigh aircraft and calculate new weight and balance records.
How would you determine the empty weight and empty weight C.G. of an aircraft if all weight and balance records are missing?
By adding weight in the rear of the aircraft.
If the forward C.G. Limit of an aircraft is exceeded after installing several items in the engine compartment, how could the limit be returned to limits without removing or changing any of the newly installed equipment?
increase in current
In a DC circuit, what occurs when voltage is increased while resistance remains constant?
No.
Is there a federal regulation that requires the regular reweighing of private aircraft?
Slack, flexing, twisting, bending, clearance, and clamps
Name considerations when installing hose assemblies?
With the use of built in level scale and a plumb bob
Name one common method of leveling aircraft during weight and balance?
Metal tubing or flexible house and fittings
What are aircraft plumbing lines usually made of?
Thermal, light, pressure and chemical
What are four sources of electrical power?
when two or more generators are operated at the same time to supply power for a load that must be shared equally.
What are paralleling generators and how is the load distributed?
Buna-N, neoprene, Butyl, ethylene, teflon.
What are some synthetic materials commonly used to manufacture flexible hoses?
Voltage, Current & Resistance
What are the elements of Ohm's Law?
Wire gauge, length, temperature and material
What are the four factors that affect the resistance of an electrical conductor?
Placards must include ballast location, limits on contents, weight necessary under load requirements.
What are the placards requirement for ballast?
series, parallel, and complex
What are the three types of DC electrical circuits?
Ampere-hours
What are the units that battery capacity are measured in?
Inches from datum and percent of mean aerodynamic chord.
What are two common ways of representing the c.G of an aircraft?
a magnetic fields generated; the conductor heats up
What are two things that happen when current flows through a conductor?
Inductive, and capacitance reactance.
What causes opposition to the flow of current in an AC circuit?
source, Load/resistance and conductors
What does an electrical circuit consist of?
Specific gravity will vary with temperature. If the temperature of electrolyte increases, the specific gravity reading will be high.
What happens to specific gravity of the electrolyte in lead acid battery when the temperature changes?
Drawing number, name of part, scale, date, firm, draftsman name, checker and approving official.
What information is given in the title block of a blueprint?
a hydrometer
What instrument is used to determine the specific gravity of electrolyte in a lead acid battery?
weight of extra equipment used for measuring the aircraft. Subtracted from scale readings to obtain Empty Weight
What is 'tare weight' and how is it handled when making weight and balance calculations?
Items of weight placed inside the aircraft to attain the desired center of gravity location
What is a ballast?
distance from the datum in inches along longitudinal axis.
What is a fuselage station number?
1,000 watts
What is a kilowatt?
It is a basic drawing that shows specific information and minimum details needed to manufacture a part.
What is a sketch for a repair?
Used to determine load distribution so that aircraft remains within center of gravity.
What is an aircraft loading graph?
the coil
What is an example of an inductor in a magneto?
A drawing which illustrates multiple views and angles of an object.
What is an orthographic projection?
weight which placed in the aircraft to attain a desired C.G.
What is ballast?
total opposition for AC to flow caused by effects of resistance, inductive reactance and capacitance reactance.
What is impedance?
When voltage is induced by magnetic flux lines in an AC circuit
What is inductance?
fuel that should be used in weight and balance for extreme condition check. In reciprocating engine its max except takeoff power divided by 2
What is meant by 'minimum fuel' and how is it calculated for weight and balance?
the fuel remaining in the lines and tanks after fuel exhaustion. Unusable Part of empty weight
What is meant by 'residual' fuel?
distance from the most forward to the most rearward acceptable center of gravity.
What is meant by the center of gravity range?
Permanent ballast do not remove in red paint.
What is recommended marking for permanent ballast?
list of materials and parts needed for fabrication or assembly of a component
What is the "bill of materials" associated with aircraft blueprint?
the distance in inches an item is located from the datum. Obtained By measurement or weight and balance records
What is the 'arm' of an item and how is it obtained?
A diode
What is the basic component that allows current to flow in one direction?
Magnetic flux lines.
What is the common name for lines of force that make up a field surrounding a magnet?
Electromagnetism.
What is the concept that describes the relationship between electricity and magnetism?
imaginary vertical lines from all measurements are taken and to determine the relative location of items in the aircraft.
What is the datum and its purpose when making weight and balance computations?
The center of gravity location in a helicopter is much more critical than fixed wing aircraft. In helicopter cg range is less than 3 inches.
What is the difference between fixing wing and rotor wing(helicopter) aircraft C.G. ranges?
transfer of electrical energy by means of a magnetic field
What is the electromagnetic induction?
to store electricity
What is the function of a capacitor?
To limit current.
What is the purpose of a resistor?
Used for objects of uniform thickness, such as gaskets, shims and plates.
What is the purpose of one view drawings?
Lay line indicates if the hose has twisted during installation. No twisting allowed.
What is the purpose of the identification stripe running along the length of a flexible hose?
quickly disconnecting without a loss of fluid or air entering the system.
What is the purpose of using quick disconnect couplings in fluid systems?
for safety and efficiency in flight.
What is the purpose of weight and balance control?
Low internal resistance cell, causes current to increase across the cell and heats up.
What is the result of an imbalanced cell in nickel cadmium battery?
Hertz
What is the standard unit of measure for frequency?
Farad
What is the unit of measure for capacitance?
Ohms
What is the unit of measurement for impedance?
watt 746 Watts = 1hp
What is the unit of measurement of power in a DC circuit?
C.G. Limits, datum, max weight, leveling means, seat location, fuel capacity and location, oil weight and location.
What items concerning weight and balance could be found in type certificate data sheet?
Annealed or 1/4 inch hard corrosion resistant steel.
What material should be selected for high pressure rigid fluid lines?
No more than 75% of original diameter
What percentage of flattening is allowed when bending metal tubing?
Fluid lines always routed below electrical wiring at-least 6 inches apart. Both fluid and wiring should be fastened to aircraft structure.
What precautions should be taken when routing fluid lines adjacent to electrical wiring?
two times the operating pressure of the hose.
What pressure is used to proof-test a flexible hose assembly?
a capacitor
What represents capacitance in an AC circuit?
Determine exact weight per gallon then subtract the useable fuel in weight and balance calculations.
What should be done in regards to aircraft fuel when performing weight and balance when draining is not an option?
3/8 inches above the plates or above the baffle place in each cell
What should be the correct electrolyte level in a properly serviced battery?
between 1.225 and 1.300
What should be the specific gravity of the electrolyte in a fully charge lead acid battery?
A schematic
What type of drawing is most helpful in troubleshooting a system?
a hidden view line is a medium width line made up of short dashes. Center lines are thin lines made up of alternating long and short dashes. Alternate position lines are medium with line made up of one long and two short evenly spaced dashes.
What type of lines are used on aircraft drawings to indicate hidden views, center lines, and alternate position lines?
Stainless steel
What type of material should fittings be made of when used with stainless steel tubing?
moment is a force which tends to rotate the aircraft on its axis. Obtained by multiplying the weight by the distance from the datum.
When computing weight and balance, what is the 'moment' and how is it obtained?
above 90°F or below 70°F
When using a hydrometer to check the charge of a lead-acid battery, at what temperatures must a correction factor be applied to the reading?
all operations equipment whether require or optional must be included in empty weight
When weighting an aircraft to determine the empty weight C.G., what must you do with regard to the fixed equipment which is normally carried in the aircraft?
front of the center of lift.
Where is the center of gravity located in relation to the aerodynamic center of lift for most airplanes?
lower right corner
Where is the title block usually found on an aircraft drawing?
in the airplane flight manual or weight and balance records.
Where must a record of the most recent empty weight and center of gravity be kept?
shorthand used in drawings to keep writing and drawing to a minimum.
Why are symbols used when drawing aircraft blueprints?
solid narrow lines, broken at midpoint for measurements. indicate the size.
Why are the dimensions used, and how are they shown on the aircraft drawings?
Specific gravity of the electrolyte in a nickel-cadmium battery does not change appreciably during charge or discharge
Why can a hydrometer NOT be used to determine the charge of a nickel-cadmium battery?
when the empty weight C.G. falls within the empty weight C.G. range, it is unnecessary to perform a weight and balance check if standard loading and seating arrangements are used.
Why do some manufactures specify an empty C.G. even though the aircraft is not operated at this empty weight?
some aircraft certified in both normal and utility categories which means 2 different useful load calculations.
Why must the aircraft category be considered when computing weight and balance?