Engine & System Operation Flashcards
1
Q
What documents are required onboard an aircraft prior to flight?
A
ARROW
A- Airworthiness certificate
R- Registration certificate
R- Radio Station License
O- Operations Limitation
W- Weight and Balance data
2
Q
What privileges and limitations apply to a private pilot?
A
+No person who holds a PPL may not :
- Act as PIC of an a/c that is carrying passengers or property for compensation or hire, nor may that person, for compensation or hire, act as PIC of an a/c
+ They may:
- Act as PIC in connection w/ a business or employment if it is only incidental to that business/employer and does not carry passengers/property for compensation or hire
- May not pay less than the pro rata share of the operating expenses of a flight w/ passengers, provided the expenses involve only fuel, oil, airport expenditures, or rental fees
- Act as PIC of charitable/nonprofit/community event described in 14CFR 91.146 as long as sponsor and pilot comply with said CFR
-
3
Q
Explain pro rata share:
A
- It means proportional share of the flights operating expenses (i.e. fuel, oil, airport expenditures, or rental fees)
4
Q
What are the 4 main control surfaces and what are their functions?
A
- Elevators: Control the “pitch” of the aircraft
- Ailerons: Control the “roll” of an aircraft
- Rudders: Control the “yaw” of the aircraft
- Trim: Are labor-saving devices that enable the pilot to release manual pressure on the primary control
5
Q
What are the flaps, and what are their function?
A
- The flaps are a moveable panel, that extends downwards on a hinge.
- They interrupt the air flow below the wing and provide both lift and drag. Their purpose is to provide a steeper angle of descent and slower airspeed during a landing approach.
- They may, in some instances, be used for short-field takeoff
6
Q
Describe the landing gear system on this airplane?
A
- The landing gear system is a tricycle-type system utilizing two main wheels and a steerable nose-wheel
- Tubular spring steel provide the two main gears with shock absorption, while the nose-wheel is composed of an air/oil type of shock absorption system.
7
Q
How are the flight controls operated?
A
- The flight control surfaces are manually actuated through use of either a rod or cable system.
- A control wheel actuates the ailerons and elevator, and rudder/brake pedals actuate the rudder.
8
Q
Describe the brake system of this aircraft?
A
- The brake system is a hydraulic brake system and operate through a series of hydraulic pressure actuated when the toe brakes are applied.
- Brake fluid is fed through the system via brake lines from the brake master cylinder, which are connected to both pilots’ rudder pedals.
9
Q
What type of hydraulic fluid does your aircraft use?
A
- A mineral based hydraulic fluid (MIL-H-5606) is the most widely used for small a/c. It has an odor similar to penetrating oil, and is dyed red.
- A newer, fire resistant fluid (MIL-H-83282) is also used in small a/c and is dyed red.
10
Q
How is steering accomplished on the ground?
A
- Through a series of spring-loaded bungee (push-pull rod) when a rudder pedal is depressed, the pivotal portion of the nose-wheel strut will turn the nose-wheel.
11
Q
What type of engine does your a/c have?
A
- 4 cylinder
- Overhead-valve
- Air-cooled
- Carbureted engine
- The engine is manufactured by Lycoming and rated @110hp
12
Q
What are the four stages in a four stroke engine?
A
- Intake
- Compression
- Power
- Exhaust
13
Q
What happens on the intake stroke of a four stroke engine?
A
- The valve opens, and the piston moves down the cylinder, allowing fuel/air mixture into the chamber
14
Q
What occurs during the compression stroke in a 4 stroke engine?
A
The piston moves back to the top of the cylinder compressing the fuel/air mixture as the valve is closed, this allows for a greater power output once the mixture is ignited.
15
Q
What occurs during the power stroke of a four stroke engine?
A
- The mixture in the cylinder is ignited and forces the piston down in the cylinder, in turn, turning the crankshaft.
16
Q
During the exhaust stroke of a four stroke engine?
A
The cylinder is purged of burned gases as the piston moves back towards the cylinder head again
17
Q
What does the carburetor do?
A
Carburetion is the process of mixing fuel and air in the correct proportions in order to form a combustible mixture.
The carburetor vaporizes liquid fuel into small particles & then mixes air with it. It measures the air flow and meters fuel accordingly.
18
Q
How does carburetor heat work?
A
A carburetor heat valve, controlled by the pilot, allows unfiltered, heated air from a shroud located around the exhaust riser or muffler to be directed into the induction air manifold prior to the carburetor. Carb heat should be used anytime suspected or known carb icing conditions exist.
19
Q
What does the mixture control do?
A
- Regulates the fuel-to-air ratio. This prevents the mixture from becoming too rich at high altitudes, due to decreasing air density. It’s also used to lean the mixture during cross-country flights to conserve fuel and provide optimum power.
20
Q
What change occurs to the fuel/air mixture when applying carburetor heat?
A
Normally, the introduction of heated air into the carburetor will result in a richer mixture. Warm air is less dense, resulting in less air for the same amount of fuel. Use of carb heat can cause a decrease in engine power of up to 15%.
21
Q
Describe a fuel injection system installed in some aircraft.
A
The fuel injection system injects fuel directly into the cylinders, or just ahead of the intake valve.
It’s components are:
1. Engine-Driven Fuel Pump: Provides fuel under pressure from the fuel tank to the fuel/air control unit.
- Fuel/Air Control Unit: Meters fuel based on the mixture control setting and sends it to the fuel manifold valve at a rate controlled by the throttle.
- Fuel Manifold Valve:Distributes fuel to the individual fuel discharge nozzles.
- Discharge Nozzles: Located in each cylinder head, these inject the fuel/air mixture at the precise time for each cylinder directly into each cylinder intake port.
- Auxiliary Fuel Pump: Provides fuel under pressure to the fuel/air control unit. Used for engine starting and/or emergency use if the engine-fuel pump fails.
- Fuel Pressure/Flow Indicators: Measures metered fuel pressure/flow
22
Q
What type of ignition system does your airplane have?
A
- The engine is provided by 2 engine-driven magnetos, and 2 spark plugs per cylinder.
- The ignition system is completely independent of the a/c electrical system.
- The magnetos are engine driven self-contained units supplying electrical current without using an external source of current. However, must be actuated by the a/c battery during startup.
- The battery, with the starter and a series of gears, rotate the engine crankshaft which actuates the magnetos.
- Once the engine starts, the starter system is disengaged, and the battery no longer contributes to the actual operation of the engine.
23
Q
What are 2 main advantages of a dual ignition system?
A
- Increased safety: In case one system fails the engine may be operated on the other until a landing is safely made.
- An even and complete combustion in the chamber. The cylinder is ignited on both sides of the cylinder and burn down towards the center of the cylinder.
24
Q
What type of fuel system does your a/c have?
A
- The fuel system is a “gravity fed” system. Using gravity, the fuel flows from two wing fuel tanks to a fuel shutoff valve which, in the “on” position, fuel is fed through a strainer then to the carburetor. From there, the fuel is mixed with air and then fed into the cylinders via the intake manifold.
25
What purpose do fuel tank vents have?
When fuel goes down (due to the gravity fed system) a vacuum is created. Without the fuel tank vent, the fuel tank would encounter a decrease in fuel flow due to the vacuum and in turn the engine would shut down.
Fuel tank vents provide outside air to fill the void of fuel leaving the tank, thus preventing the vacuum forming.
26
Does your aircraft have a fuel pump?
No. Fuel is gravity fed, and this is happens only due to the location of the tank in regards to the carburetor. It is constantly under positive pressure to do so.
However, there are instances where some a/c do not have this ability, or more pressure is needed than a gravity fed cannot supply. In this instance a auxiliary and an engine driven fuel pump would be needed.
27
What type of fuel does your a/c take?
100LL and it has a blue color dye to it
28
Can other grades of fuel be used if I do not have the appropriate grade available?
It is possible, but not desirable to use the next HIGHER grade as a substitute. The AFM/POH should be referenced.
29
Can auto gas be used to replace a specific fuel grade?
Auto gas should never be used in aircraft engines unless the aircraft has been modified with an FAA-issued Supplemental Type Certificate (STC)
30
What color of dye is added to 80, 100, 100LL, Turbine?
Red = 80 (Obsolete)
Green = 100 (Obsolete)
Blue = 100LL
Jet A = Colorless or Straw
31
If a non-turbine piston engine powered airplane is accidentally fueled with JET-A fuel, will it start?
Yes. Reciprocating engines may run briefly on jet fuel, but detonation and overheating will soon cause power failure.
There may be a small amount of Avgas remaining in the aircraft's fuel system. This may allow and engine to taxi, perform runup, and possibly takeoff before experiencing an engine failure.
32
How can you tell the difference between Avgas (100LL blue) and Jet A fuel grade?
Other than the kerosene smell and oily feel when rubbed between the fingers, it can be very difficult to visually identify an accidental mixture of 100LL Avgas and Jet A
33
What is the function of the manual primer, and how does it operate?
The manual primer's main function is to provide assistance in starting the engine. The primer draws fuel from the fuel strainer and injects it directly into the cylinder intake ports. This results in a quicker, more efficient engine start.
34
Describe the electrical system of your aircraft?
Electrical energy is provided by a 28-volt DC system powered by an engine-driven 60 amp alternator and a 24-volt battery
35
How are the circuits for the various electrical accessories within the aircraft protected?
Electrical accessories are protected with circuit breakers, and through fuses (if equipped). Circuit breakers perform the same function as fuses except that when an overload occurs, a circuit breaker can be reset.
36
The electrical system provides power for what equipment in an airplane?
1. Radio Equipment
2. Turn coordinator
3. Fuel Gauges
4. Pitot Heat
5. Landing Light
6. Taxi Light
7. Strobe Light
8. Interior Light
9. Instrument Light
10. Position Light
11. Flaps
12. Stall warning system
13. Oil temperature gauge
14. Electrical fuel Pump
37
What does the ammeter indicate?
It indicates the flow of current, in amperes, from:
1. The alternator to the battery
or
2. From the battery to the electrical system
With the engine running and master switch on:
The ammeter will indicate the charging rate to the battery.
38
What occurs when the alternator has gone off, and is no longer functioning, or if the electrical load exceeds the output of the alternator?
The ammeter will indicate a discharge rate of the battery (Needle in the negative side of the charging rate)
39
When the engine is running and master switch on, the ammeter will indicate:
A charging rate to the battery
40
What function does a voltage regulator have?
The voltage regulator is a device which monitors system voltage, detects changes, and makes the required adjustments in the output of the alternator to maintain a constant regulated system voltage. It must do this at low RPM and high RPM settings. In a 28-volt system, it will maintain 28 volts +/- 0.5 volts
41
Why is the generator/alternator voltage output slightly higher than the battery voltage?
The difference in voltage keeps the battery charged. Example: 12-volt battery would be supplied with 14 volts.
42
How does aircraft cabin heat work?
Fresh air, heated by the exhaust shroud, is directed to the cabin through a series of ducts.
43
5 basic functions of engine oil
1. Lubricates: the engine's moving parts
2. Cools: The engine by reducing friction
3. Removes: Heat from the cylinders
4. Seals: Provides a seal between the cylinder walls and pistons
5. Cleans: By carrying off metal and carbon particles and other oil contaminants.
44
What causes carb icing, and what are the first indications of its presence?
The vaporization of fuel, combined with the expansion of air as it passes through the carburetor, causes a sudden cooling of the mixture.
The temp of air passing through the carb my drop as much as 60f within a fraction of a second. Water vapor is squeezed out by this cooling, and if the temps in the carb reaches 32f or below, the moisture will be deposit as frost or ice inside the carb
Aircrafts with fixed-pitch propeller, the first indication of carb icing is loss of RPM.
Aircrafts with controllable-pitch propellers, the first sign of icing is a drop in manifold pressure.
45
What method is used to determine that carb ice has been eliminated?
Fixed Propeller Aircraft: When heat is first applied, there will be a drop in RPM
Controllable Pitch Propeller: A drop in manifold pressure
- If ice is present there will be a rise in RPM or manifold pressure after the initial drop (followed by engine roughness
- When carb heat is turned off, the RPM or manifold pressure, will rise to a setting higher than before the application of the heat. The engine should run smoothly after ice has been removed.
46
What conditions are favorable for carb icing?
Most likely to occur when temps are below 70f (21c) and relative humidity is above 80%.
Due to how fast cooling takes place in the carburetor, temps as high as 100f (38c) and humidity as low as 50% can happen as well.
47
Define the terms anti-icing and deicing equipment and state several examples of each.
Anti-icing Equipment: Prevents ice from forming on certain protected surfaces.
Examples: Pitot tube, heated windshield, carb heat, heated fuel vents, static ports, propeller blades with electro-thermal boots etc.
Deicing Equipment: Removes ice that has already formed on protected surfaces. It is generally limited to pneumatic boots on the wing and tail leading edges.
48
Describe how an aircraft deicing system works?
Upon pilot actuation, boots attached to the wing leading edges inflated with air from a pneumatic pump(s) to break off accumulated ice. After a few seconds of inflation, they are deflated back to their normal position with vacuum assistance. The pilot monitors the buildup of ice and cycles the boots as directed in the AFM/POH
49
If an airplane has anti-icing and/or deicing equipment installed, can it be flown into icing conditions?
Even though it may appear elaborate and complete, the presence of anti-icing and deicing equipment does not necessarily mean an airplane is approved for flight in icing conditions. The AFM/POH, placards, and even the manufacturer should be consulted for specific determination of approvals and limitations.
50
What is detonation?
An uncontrolled, explosive ignition of the fuel/air mixture within the cylinder's combustion chamber. It causes excessive temperature and pressure, which, if not corrected can quickly lead to failure of the pison, cylinder, or valves. In less severe cases, detonation causes engine overheating, roughness, or loss of power. Detonation is characterized by high cylinder head temps, and is most likely to occur when operating at high power settings.
51
What are some of the most common operational causes of detonation?
- Using a lower grade fuel than specified by the manufacturer
- Operating with extremely high manifold pressures in conjunction with low RPM
- Operating the engine at high power settings with an excessively lean mixture.
- Extended ground operations or steep climbs where cylinder cooling is reduced
52
What action should be taken if detonation is suspected? (FAA-H-8083-25)
Detonation may be avoided by following these basic guidelines during the various phases of ground and flight operations:
1. Ensure that the proper grade of fuel is used.
2. Keep the cowl flaps (if available) in the full-open position while on the ground to provide the maximum airflow through the cowling
3. Use an enriched fuel mixture, as well as a shallow climb angle, to increase cylinder cooling during takeoff and initial climb
4. Avoid extended, high power, steep climbs
5. Develop the habit of monitoring the engine instruments to verify proper operation according to the procedures established by the manufacturer
53
What is pre-ignition?
Premature combustion in the cylinder; prior to the engine's normal ignition event
54
What causes pre-ignition?
Excessive cylinder temperatures caused by:
- Carbon or lead deposit in the combustion chamber
- Cracked spark plug tip
55
What happens as a result of pre-ignition in an engine?
- Reduced engine power and high operating temps
56
Actions to take if pre-ignition is suspected?
Corrective actions for pre-ignition include any type of engine operation that would promote cooling, such as:
1. Reduce Power
2. Reduce the climb rate for better cooling
3. Enrich the fuel/air mixture
4. Open the cowl flaps if available
57
During the before-takeoff runup, you switch the magnetos from the "BOTH" position to the "RIGHT" position and notice there is no RPM drop. What condition does this indicate?
The left P-lead is not grounding, or the engine has been running only on the right magneto because the left magneto has totally failed.
58
Ammeter indicates a right deflection (positive). What does this mean after starting, and also during the flight?
After Starting:
1. Power from the battery used for starting is being replenished by the alternator.
2. If a full-scale charge is indicated for more than 1 minute, the starter is still engaged and a shutdown is indicated
During Flight:
1. A faulty voltage regulator is causing the alternator to overcharge the battery. Reset the system and if the condition continues, terminate the flight as soon as possible.
59
Ammeter indicates a left deflection (negative) both, after engine start up, and during flight. What is occurring?
After Startup:
It is normal during start. At other times this indicates the alternator is not functioning or an overload condition exists in the system. The battery is not receiving a charge.
During Flight:
The alternator is not functioning or an overload exists in the system. The battery is not receiving a charge.
Possible causes: Master switch was accidentally shut off, or the alternator circuit breaker was tripped.
60
What actions could be taken if the ammeter indicates a continuous discharge while in flight?
The alternator has quit producing a charge, so the alternator circuit breaker should be checked and reset if necessary. If this does not correct the problem, the following should be accomplished:
1. Alternator should be turned off, pull the circuit breaker (the field circuit will continue to draw power from the battery)
2. All electrical equipment not essential to flight should be turned off (the battery i now the only source of electrical power).
3. The flight should be terminated and a landing made as soon as possible.
61
What action should be taken if the ammeter indicates a continuous charge while in flight (more than two needle widths?
If an excessive rate of charge were allowed for an extended period of time, the battery would overheat and evaporate all the electrolyte at an excessive rate.
*A possible explosion of the battery could result. Also, electronic components in the electrical system would be adversely affected by higher than normal voltage. Protection is provided by an overvoltage sensor which will shut the alternator down if an excessive voltage is detected. If this should occur the following should be done.
1. Alternator should be turned off; pull the circuit breaker (the field circuit will continue to draw power from the battery
2. All electrical equipment not essential to flight should be turned off (the battery is now the only source of electrical power)
3. The flight should be terminated and a landing made as soon as possible.
62
During a cross-country flight you notice that the oil pressure is low, but the oil temperature is normal. What is the problem and what action should be taken?
A low oil pressure in flight could be the result of anyone of several problems, the most common being that of insufficient oil. If the oil temperature continues to remain normal, a clogged oil pressure relief valve or an oil pressure gauge malfunction could be the culprit . In any case, a landing at the nearest airport is advisable to check for the cause of trouble.
63
What procedures should be followed concerning a partial loss of power in flight?
The first priority is to establish and maintain a suitable airspeed (best glide airspeed if necessary). Then, select an emergency landing area and remain within the gliding distance. As time allows, attempt to determine the cause and correct it.
Complete the following checklist:
1. Check carb heat
2. Check the amount of fuel in each tank and switch fuel tanks if necessary.
3. Check the fuel selector valve's current position
4. Check mixture control
5. Check the primer control is all the way in and locked.
6. Check the operation of the magnetos in all three positions; both, left or right.
64
What procedures should be followed if an engine fire develops in flight?
1. Mixture - IDLE CUT-OFF
2. Fuel Selector - OFF
3. Master Switch - OFF
4. Cabin Heat and Air Vents - Closed/ OFF
65
What instruments operate off the pitot/static system?
1. Altimeter
2. VSI
3. Airspeed Indicator
66
How does an altimeter work?
A sensitive altimeter is an aneroid barometer that measure the absolute pressure of the ambient air and displays it in terms of feet above a selected pressure level.
The sensitive element in a sensitive altimeter is a stack of evacuated, corrugated bronze aneroid capsules.
The air pressure acting on these aneroids tries to compress them against their natural springiness, which tries to expand them. The result is that their thickness changes as the air pressure changes. Stacking several aneroids increase the dimension change as the pressure varies over the usable range of instrument.
67
What are the limitations of a pressure altimeter?
Nonstandard pressure and temperature, temperature variations expand or contract the atmosphere and raise or lower pressure levels that the altimeter senses.
On warm days: The pressure level is higher than on a standard day. The altimeter indicates lower than actual altitude.
On cold days: The pressure level is lower than on a standard day. The altimeter indicates lower than actual altitude.
Changes in the surface pressure also affect pressure levels at altitude.
Higher than standard pressure: Pressure level is higher than on a standard day. The altimeter indicates lower than actual altitude.
Lower than standard pressure: Pressure level is lower than on a standard day. The altimeter indicates higher than actual altitude.
68
Define and state how you would determine the following altitudes: absolute, indicated, pressure, true, and density.
Absolute: Is the vertical distance from the terrain below, expressed as AGL
Indicated: Is what is read in the altimeter (uncorrected) after set to the current altimeter setting
Pressure: Is the altitude that is read when the setting in the window is set to 29.92hg. Pressure altitude is used to compute density altitude, true altitude, airspeed etc.
True: Is the vertical distance the airplane is above sea level. Expressed as MSL
Density: Is pressure altitude corrected for nonstandard temperature variations. Also known as performance altitude.
69
How does the airspeed indicator operate?
The airspeed indicator is a sensitive, differential pressure gauge which measures the difference between impact pressure from the pitot head and the undisturbed atmospheric pressure from the static source. The difference is registered by the airspeed pointer on the face of the instrument.
70
What is the limitation of the airspeed indicator?
Position error: Caused by the static ports sensing erroneous static pressure. Slipstream flow causes disturbances at the static port preventing actual atmospheric pressure measurement
Density Error: Changes in altitude and temperature are not compensated for by the instrument.
Compressibility Error: Caused by the packing of air into the pitot tube at high airspeeds, resulting in higher than normal indications. It is usually not a factor at slower speeds.
71
What are the different types of aircraft speeds?
Indicated Airspeed (IAS): What's read on the ASI, not corrected for indicator, position, or compressibility errors
Calibrated Airspeed (CAS): The airspeed indicator reading corrected for position, and instrument errors. Equal to TAS at sea level in standard atmosphere.
Equivalent Airspeed (EAS): ASI reading corrected for position, or instrument error, and adiabatic compressible flow.
True Airspeed (TAS): CAS corrected for altitude and nonstandard temp; the speed of the aircraft in relation to the air mass in which it is flying.
72
Name several airspeed limitations not marked on the face of the airspeed indicator?
Va: Max speed without causing structural damage. Abrupt controls at this speed can damage structure.
Vlo: Max speed for extending or retracting landing gear is a/c equipped with retractable landing gear.
Vx: Important when a short-field takeoff to clear an obstacle is required.
Vy: Airspeed that will give the most altitutude in a given period of time.
73
What flight instruments contain gyroscopes?
1. Turn coordinator
2 .Heading indicator (directional gyro)
3. The attitude indicator (artificial horizon)
74
2 Fundamental Properties of a gyroscope?
- Rigidity in Space: The gyroscope remaining in a fixed position in the plane in which it it spinning
- Precession: The tilting or turning of a gyro in response to a deflective force. This is felt at a point 90 degrees later in the direction of the rotation.
75
What instruments use a gyroscope?
- Attitude Indicator
- Heading Indicator
- Turn Coordinator
76
If the static port is blocked, what instruments will be affected, and what will happen?
- VSI
- Altimeter
- ASI
If the static port is blocked, the VSI and altimeter will freeze at the last reading
The ASI read erroneously because the lack of static pressure read from the static port
77
If the pitot tube ram air port gets frozen, what happens to the diaphragm within the airspeed indicator?
When the pitot ram air is frozen, the forced air is let out through the drain hole on the back of the pitot tube inlet.
78
If the drain and the ram inlet are frozen what will happen to the airspeed indicator?
- The airspeed indicator will act as an altimeter with the assistance of the static port equalizing the pressure inside the instrument.
79
When would the airspeed indicator freeze?
When the pitot ram, drain hole and static port all become blocked
80
Which instrument of the 6 pack, uses a gyroscope using electrical power?
The turn coordinator
81
How would you conduct a standard rate of turn when referencing the turn coordinator?
Keeping the ball inside the lines, and the airplane in the turn coordinator wings at the second tick mark would indicate a coordinated turn/
82
What is the standard rate of turn rate?
3 degrees per second
83
What does the turn coordinator indicate?
It indicates the rate and direction of turn; IT DOES NOT DISPLAY A SPECIFIC ANGLE OF BANK!
84
What is the inclinometer?
- It's the ball in the tube on the lower portion of the turn coordinator.
- It shows the aircraft yaw/ side to side movement of the aircraft's nose
- Coordinated flight is maintained by keeping the ball centered
85
Where is the inclinometer located?
In the bottom portion of the turn coordinator
86
What is gyroscopic precession?
- The turning of a gyroscope in response to a deflective force
- The force, when applied, is felt 90 degrees from where the force was applied
87
What are the gyroscopic principle used by flight instruments?
- Gyroscopic precession
- Rigidity in space
88
What is rigidity in space?
- The gyroscope remaining fixed in a fixed position in the plane in which it is spinning
89
What power sources are used to power the gyroscopic instruments in an airplane?
- Vacuum, pressure, or electrical
90
How does the vacuum system work?
- The engine-driven vacuum pumps provides suction from outside which is then pulled through the instrument case and back out the cowling
- Normal pressure entering the case is directed against the rotor vanes to turn the gyro at high speeds
91
How does the attitude indicator work?
- The gyro in the attitude indicator is mounted on a horizontal plane and depends on rigidity in space for operation
92
What is an induction system?
It's a system that brings air and mixes it with fuel for combustion in the engine cylinders
93
What are the 2 types of induction systems?
1. Carburetor
2. Fuel Injection
94
What are the 2 types of carburetor systems used in an aircraft?
1. Float type carburetors
2. Pressure type carburetors
95
How does a float type carburetor work?
1. Air is brought in through the air filter at the front of the engine cowling
2. Air flows into the carburetor through the venturi; a low pressure area is created by the shape of the venturi.
3. Fuel flow through a main fuel jet, located at the throat, is mixed with the pressured air and flows into the intake manifold, and into the chambers to be ignited in the cylinder
96
What are disadvantages of float-type carburetors?
1. They don't function well during abrupt maneuvers
2. The discharge of fuel at low pressure leads to incomplete vaporization and difficulty in discharging fuel in some types of supercharged systems
3. Carb icing
97
Why should you lean the fuel mixture at higher altitudes?
- Because the density of air entering the carburetor decreases, causing a richer mixture
98
What does a fuel mixture that is too rich do to the engine?
- Carbon build up can occur at the on the spark plug
- Too rich a mixture lowers the temperature inside the cylinder prohibiting a complete combustion of the fuel
99
High density altitude means better or worse performance for your aircraft?
- Worse performance because high density means air density is reduced
100
Carb icing will usually form in what temperature, and what percentage of humidity?
- 21 degrees celsius (70 degrees fahrenheit) and relative humidity above 80%
- 38 degrees celsius (100 degrees fahrenheit) and 50% humidity
101
If air intake clogs, what's an alternate source of air for the carburetor?
- Carburetor heat
102
When throttle is closed during flight (power idle) you should____.
- Apply carburetor heat to prevent icing
103
What are the components of a fuel-injection system?
1. Engine-driven fuel pump
2. Fuel-air control unit
3. Fuel Manifold (distributor)
4. Discharge nozzles
5. Auxiliary fuel pump
6. Fuel pressure/flow indicators
104
What gauge is usually associated with supercharges and turbosuperchargers?
- Manifold pressure gauge
105
Abrupt temperature fluctuations in the engine is caused by?
- High speed descents that shock cool the engine
106
Operating the engine at higher than its designed temperature can cause?
1. Loss of power
2. Excessive oil consumption
3. Detonation
4. Excessive cylinder damage
107
If airplane is not equipped with cowl flaps, what can you do to cool the engine?
1. Increase the airspeed
2. Reducing power and/or enrich fuel-air mixture
108
What is detonation?
- An uncontrolled, explosive ignition of the fuel-air mixture within the cylinder's combustion chamber
- It causes excessive temperatures and pressures that can lead to failure of the piston, cylinder, or valves.
- It causes engine overheating, roughness, or loss of power
109
Common causes of detonation:
1. Use of lower fuel grade
2. Operation of engine with high manifold pressures in conjunction with low rpm
3. Operation of the engine at high power setting with an excessively lean mixture
4. Maintaining extended ground operations or steep climbs in which cylinder cooling is reduced
110
Avoid detonation by doing the following:
1. Use proper fuel grade
2. Keep cowl flaps open (if available)
3. Use an enriched fuel mixture
4. Use a shallow climb angle, to increase cylinder cooing during takeoff and initial climb
5. Monitor engine instruments to verify proper operation
111
What's preignition?
- The pre-ignition of the fuel-air mixture; as opposed to the timed normal ignition
- Caused by residual hot spot in the chamber, often created by a small carbon deposit on a spark plug, cracked spark plug
- Can cause severe damage due to expanding gasses exerting excessive pressure on the piston while it's on its compression stroke
112
Pilots who perform preventative maintenance must make an entry in the maintenance record of the aircraft, and must include what?
1. A description of the work done
2 The date of completion work performed
3. The pilot's name, signature, certificate number, and type of certificate held
113
What are airworthiness directives?
- They are notices to aircraft owners and other interested persons of unsafe conditions and to specify the conditions under which the product may continued to be operated.
114
How the Altimeter work?
- The static port feeds the outside air pressure at given altitude into the altimeter instrument chamber
- Aneroid wafers with a sealed internal pressure of 29.92hg, located inside the instrument, contracts and expands based off of the pressure fed into the chamber from the static port
- At higher pressures, the wafers contract and drive the needle in the indicator down
- At lesser pressures, the wafers are allowed to expand, and drives the needle upward
115
One a constant speed propellor, the throttle controls the engine power output which is registered on what flight instrument?
- Manifold pressure gauge
116
In a constant speed propellor, the propellor control changes:
- The pitch angle of the propeller and governs the RPM which is indicated on the tachometer
117
If you see gyro flags on your instrument, what should you do?
- It means that instrument has failed, and you should cover it up so it doesn't distract you from flying using other instruments that's working properly
118
What instruments are controlled by air/vacuum system gyro?
- Heading Indicator
- Attitude Indicator
119
If the attitude indicator fails, what instrument can you use for banking info?
- Turn coordinator
120
What is a slip when making a standard rate turn?
- A slip is when there's not a great enough rate of turn
- The nose is outside of the turn/bank
121
What is a skid when making a turn?
- A skid is when there is too much rate of turn
- The nose is on the inside of the turn, and the turn becomes too tight
122
What instruments are in the 6 pack?
1. VSI
2. ASI
3. Turn Coordinator
4. Altimeter
5. Heading Indicator
6. Attitude Indicator
123
What are the pitot static instruments?
1. Altimeter Indicator
2. VSI
3. ASI
124
3 Gyroscopic System Instruments
1. Turn Coordinator
2. Attitude Indicator
3. Heading Indicator
125
Fuel indicator limitations:
Should not be relied on during:
1. Slips
2. Skids
3. Unusual attitudes
126
What engine instrument shuts down the alternator?
Overvoltage sensor
127
In cooler temps, after engine shutdown what happens to injector nozzles?
Fuel injector nozzles lines remain nearly full of fuel
128
What are some limitations with your fuel system?
- Fuel pump could fail
- Water/debris in the fuel system
- Fuel leak
- Inaccurate reading during unusual attitudes, and slips
- Not keeping track of fuel burn (time to empty)
