O&P PowerPlant

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O&P PowerPlant
2014-01-19 13:28:06
O&P PowerPlant
O&P PowerPlant
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  1. what procedure should be done when valve blow-by is indicated by a hissing sound when pulling the prop through?
    compression testing to find faulty cylinder
  2. running valve clearance on hydraulic lifters
  3. what does a cold cylinder indicate on a running engine
    lack of combustion on that cyliner
  4. what can be learned from a compression check
    if valves, rings, and pistons are sealing
  5. how do you repair a loose stud on a crankcase
    remove the stud and check threads, may need to over size the stud
  6. How do you check a cylinder for out of roundness?
    T-gauge & micrometer. Or inside micrometer. Measure the cylinder at top & skirt 90 degrees apart.
  7. Types of rod used in radials?
    Master & articulating rod assemblies.
  8. Name types of piston rings
    Compression, oil control, & oil scraper.
  9. What is the purpose of oil control rings?
    Regulate oil film thickness on the cylinder wall.
  10. Types of bearings used in reciprocating engines?
    Plain, ball, and roller bearing.
  11. Where are cracks most likely found on pistons?
    Highly stressed areas, base of the pin bosses, junction of the head & walls, and ring lands.
  12. How are ring gaps oriented?
    Staggered (not aligned) to prevent blow by.
  13. What is the purpose of valve overlap?
    Permits better volumetric efficiency and lowers cylinder operating temp.
  14. What is the purpose of crankshaft dynamic dampers?
    Reduce engine vibrations.
  15. What is a serviceable limit?
    The part will most likely last until next TBO interval.
  16. Name at least one part of an inspection after a prop strike
    (Not stoppage) Engine mounts, crank case & nose section of crank case, oil & oil screen/filters for metal contamination, inspect prop shaft or crankshaft for alignment or run out.
  17. What precautions should be ovserved before engine removal?
    Disconnect battery, chock, tail stand, fuel valves off.
  18. What is an indication of primer leaking?
    Rough idle.
  19. Result of incorrect ring installation?
    Excessive oil consumption.
  20. What are indications of induction system leakage?
    Low power& uneven running.
  21. Manufactured rebuilt engine history?
    No history, zero time-record issued.
  22. What is used to prevent valve surge?
    Two or more springs are used on each valve.
  23. Name the major components of a typical gas turbine
    Air inlet, compressor section, combustion section, turbine section, exhaust section, accessory section.
  24. What determines amount of air passing through a turbine engine
    Compressor speed, forward speed, air density
  25. Name two principal types of compressors currently in use
    Centrifugal & axial flow
  26. How are turbine blades attached to rotor disks
    • 1. bulb-type root
    • 2. Fir tree-type root
    • 3. Dove tail-type root
  27. Name 3 types of combustion chambers
    • 1. Can
    • 2. Annular
    • 3. Can-annular
    • 4. Reverse flow annular
  28. Purpose of interconnect tubes between can-type combustion chambers
    Flame propagation during starting
  29. What prevents burning of the combustion chambers
    Cooling air along the inside of liner
  30. What is the unique feature of (dual) split compressor systems
    Two rotor shafts, one inside the other.
  31. What is carbon seals used for
    Oil seals in rotor shaft bearings
  32. What is the main operating difference between turbo shaft and turbo fans
    Fan air bypasses engine core
  33. What is the purpose of turbine engine compressor field cleaning
    Remove contaminant deposits and improve performance
  34. Methods used to field clean
    Fluid wash and abrasive grit blast
  35. Name the advantage of turbo fan over turbo jet
    Additional thrust without increasing fuel flow
  36. Function of axial flow turbine nozzles
    Prepare airflow for driving the turbine rotor & deflect gasses to a specific angle.
  37. Ways of relieving thermal stress on a turbine disk
    Bleed air on the face of the disk or grooving in the turbine disk
  38. Name types of compressor blade damage
    Dents, galling, pitting, cracks, scratches, burrs, burns, and gouges
  39. Used to mark hot and cold section parts
    Dye, felt tip marker, or chalk
  40. What is the effect of relative humidity on turbine power
  41. Indications of engine out of trim
    High EGT at target takeoff EPR
  42. Cause fo high EGT, low RPM and high fuel flow at all EPRs
    Turbine damage or loss of turbine efficiency.
  43. Preparation for 100 hour
    Remove cowl and clean
  44. How can you visually identify an engine
    Data plate
  45. What may be used for 100 hour inspection
    14 CFR part 43 appendix D
  46. What additional inspection must be performed if a cylinder is weak
    Internal cylinder inspection
  47. Name at least one place where operating limits may be found
    • Type Certificate Data sheet
    • Engine specifications manual
    • Aircrafts maintenance manual
  48. How does SOAP help evaluate the condition
    Identifies each wear metal and quantity present in the oil sample
  49. Approval required when engine type design in changed
    • (STC) supplemental type certificate
    • Form 337 (field approval)
  50. Why inspect engine removed from preservation
    Look for corrosion
  51. What is needed to inspect engine for conformity
    Type certificate data sheet
  52. Pub needed to check engine for normal operations
    Maintenance manual
  53. What is the purpose of a hot section inspection
    Check integrity of hot section parts
  54. Conditions under which compliance with a service bulletin is mandatory
    AD (Airworthiness Directive)
  55. Approved ops specs for commercial carrier
    Overhaul procedures require it
  56. What is fan blade shingling
    Overlapping of mid span shrouds of fan blades
  57. Pubs needed for over speed inspection
    Manufacturers maintenance publications
  58. What's required after an over temperature event
    hot section inspection
  59. Place where life limited parts are found?
    T-sheet, Airworthiness section of instructions for continued airworthiness
  60. Criteria of life limited parts? Turbines?
    Cycles, hours, or calendar date
  61. Accomplish at coast down after shut down of a turbo fan or jet
    Listen for unusual noise
  62. Why install blades at the same location where removed?
    Balance of turbine wheel
  63. Items in ops check after 100 hour
    • Power output (idle & static RPM)
    • Magnetos
    • Fuel & oil pressure
    • Cylinder & oil temperatures
  64. Where on reciprocating fuel flow indicating system is connected to fuel system
    Between pump & carburetor
  65. Basic components of a fuel flow system
    Pressure and indicator
  66. What read out is indicated on fuel flow sys
    Fuel flow in pounds or gallons per hour
  67. What is pressure range on float type carburetors
    3 to 5 PSI
  68. Reason for monitoring fuel flow
    Fuel flow is an indication of engine performance
  69. Manifold pressure gauge indicates?
    Absolute pressure in (in/hg.) inches of mercury
  70. What directly controls manifold pressure
    RPM & throttle opening
  71. On a fixed pitch, what controls MAP (manifold air pressure)
    Throttle control
  72. What does a reciprocating tachometer indicate
    Crank shaft speed
  73. What does a turbine tachometer indicate
    % of compressor RPM
  74. What does turbine EGT indicate
    Average temp of turbine discharge gases
  75. How is turbine EGT obtained
    Several probes at intervals around exhaust duct perimeter near turbine exit
  76. What pressures are measure to get EPR
    Total inlet pressure and exhaust pressure
  77. What is the torque being developed in a turbo prop indicate
    Shaft horsepower
  78. Where should the CHT (cylinder head temperature) probe be installed on a single probe system of a reciprocating engine?
    The hottest cylinder
  79. What is the electrical source for CHT (cyclinder head temp)
  80. Where is the location of the carburetor air temp bulb
    Ram air intake duct directly ahead of carburetor
  81. Probable cause for severe oil pressure drop with full oil and normal oil temp
    Transmitter or indicator malfunction
  82. How can turbine EGT system be checked without running engine
    Resistance of thermocouples & circuits
  83. When checking MAP (manifold air pressure) where should prop be set
    Low pitch
  84. Name types of fire detect systems
    • overheat
    • rate of rise
    • flame detectors
  85. What happens in a thermocouple system on a slow overheat
    Nothing, fast rise needed
  86. What happens to a thermal switch fire system when it is heated enough to operate?
    Contacts close and provide a ground for cockpit fire warning devices
  87. What electrical power is needed for a thermocouple fire protection system
    Aircraft system and thermocouple produced electricity
  88. Minimum number of thermal switches needed for a thermal switch fire protection system to operate
    At least one
  89. What system has most complete coverage
    a continuous loop system
  90. Describe the operating principle of a Kidde system
    Two wires are embedded in an Inconel tube and surrounded by a ceramic insulator. One is a ground wire the other is the positive. When the temp rises to a point, the wires conduct to complete a circuit.
  91. Describe the operating principle of Fenwall system
    Single wire is surrounded by ceramic beads in an Inconel tube. The resistance lowers with temp rise and the wire conducts to the outer tube to complete a circuit.
  92. What is the purpose of extinguishing system
    Dilute atmosphere around fire with inert gas
  93. Two methods used to distribute agent
    • perforated tubing
    • discharge nozzle
  94. What is an HRD system
    High Rate Discharge
  95. How is HRD distributed
    Open end tubes
  96. How long for HRD
    one to two seconds
  97. What group of agents is no longer being produced because of environmental concerns
    Halons or Freon or Chlorofluorocarbons (CFCs)
  98. What are the ingredients for fire
    heat, fuel, or oxygen
  99. What is the purpose of discharge cartridge? How is it activated?
    Release agent fro the bottle. Electrically from the cockpit.
  100. What is the purpose of the red and yellow discharge disks
    Red indicates a thermal discharge; yellow indicates a normal discharge
  101. What indicates low agent pressure
    Gauge mounted on fire bottle
  102. What is the proper method to check pressure of fire bottles
    Pressure/temperature chart
  103. Where can a generator rating and performance data be found
    Data plate on generator
  104. Ammeter/load meter indication when engine is running?
    Whether generator is supplying enough current or battery is discharging (connected to + post)
  105. Ammeter/Load meter indication when the engine is running?
    current leaving the generator i.e. electrical load (connect to generator output)
  106. What is used to control generator voltage output?
    field current strength
  107. What alternator component prevents batter reverse current flow
  108. Why are multiple generator systems paralleled
    Insure each generator shares an equal electrical load
  109. How many phases are used in modern aircraft
  110. What determines frequency of alternator output
    number of poles and rotation speed of the armature
  111. How does a voltage regulator control voltage of an alternator
    Regulating voltage output of the D.C. Exciter. (Field strength)
  112. Name ways to maintain 400 Hz on a large turbo just/fan engines
    • Constant Speed Drives
    • Integrated drive generators
    • variable speed constant frequency power systems (VSCF)
  113. Major parts of DC motor
    • Armature
    • field brush
    • frame
  114. 3 DC motors
    • Series
    • shunt
    • compound wound
  115. Name the components of starter
    • motor
    • gears
    • automatic engage
    • disengage mechanism
  116. Modes of turbine engine starter-generator
    works as a starter than as a generator
  117. How do we size of wire
    AWG (American Wire Gauge)
  118. Which size is the largest 10 or 14
  119. Maximum slack allowed between supports
    1/2 or less
  120. Kind of wire run close to exhaust stacks
    High temp insulation
  121. What is an indication of a dirty or worn communtator
    Starter drags
  122. What is the purpose of bonding wires
    • Return current path
    • prevent ESD
    • protect aircraft and people from lightning discharge
  123. Name the common DC motor used for starters
    Series wound
  124. Why?
    High torque under heavy loads
  125. What is the purpose of lubrication
    Reduce friction
  126. Name 2 important characteristics relating to viscosity
    • light enough to circulate
    • heavy enough to provide an oil film at temp
  127. What is the most critical lube point on a gas turbine engine
    turbine bearing
  128. What if the oils viscosity is too thin
    oil film breaks down
  129. What is the function of the dispersing agent in ashless dispersant oil
    Trap contaminants in suspension until filtered
  130. Why must aircraft oils be relatively high in viscosity
    • Large clearances
    • high temperatures
    • high bearing pressures
  131. Why are oil tanks required to have exansion space
    Expansion & air return oil (foaming)
  132. What is the purpose of the oil cooler bypass valve
    Direct oil around cooler to maintain operating temperatures
  133. Where does the temp bulb usually sense oil temp
    engine oil inlet
  134. Presence of metal in filter indicates
    Internal engine failure
  135. Two areas where turbine engine oil filter/screens may be located
    • Oil pressure system (main filter)
    • scavenge system
    • at or just before oil jets (last chance device)
  136. Name common oil contaminants
    • moisture
    • acid
    • dirt
    • carbon
    • metal
  137. What type of oils are used in turbine engines
    Synthetic oils
  138. What can cause excessive oil consumption with no leaks
    Worn or broken piston rings (reciprocating engine)
  139. What is a low oil indication
    low pressure and high temperatures
  140. Results of an obstruction in oil cooler passages
    high temperatures
  141. What causes oil foaming
    • diluted oil
    • contaminations
    • oil level too high
  142. Name two types of turbine engine oil coolers
    air and fuel cooled
  143. What controls maximum pressure in a gear type oil pump
    Relief valve
  144. What is the first step to take after finding metal in an oil filter
    Evaluate contamination IAW service manual
  145. What is the purpose of magnetos
    produce a high voltage spark across the plug gap
  146. Name three major circuits of a high tension magneto
    • magnetic
    • primary
    • secondary
  147. Name the components of a high tension magnetic circuit
    • Permanent multi pole magnetic
    • sof iron core
    • pole shoes
  148. What crank position does the ignition even occur
    Specified degrees BTC on compression stroke
  149. Where is the E gap position in a magneto
    a few degrees beyond magnetic neutral
  150. What is the purpose of a capacitor (condensor)?
    prevents arcing of the points, collapses magnetic field
  151. What happens when the magnetic rotor is in the E-GAP position and the primary breaker points are open
    The plug fires
  152. What turns ignition off
    Circuit to ground is completed
  153. What is the purpose of two magnetos
    • redundancy
    • combustion efficiency
  154. Which magneto is grounded when switch is selected to "R" position?
  155. Name the three events required to fire a plug on a specific cylinder
    • E gap
    • points open
    • distributor electrically aligned with cylinder
  156. What does timing light indicate
    Exact instant the points open
  157. Main concern when preparing magneto for installation
    Internal timing
  158. Are turbine ignitions apt to carbon foul?
    No, high energy sparks clean electrodes
  159. What is the visual indication of service life of bushes in a starter generator
    Amount of wear groove left on brushes
  160. Function of a duty cycle in relation to turbine ignition system
    Only operates for a given time, followed by a cool down period
  161. Name the three main components of turbine ignition
    • Ignition exciters
    • high tension loads
    • igniters
  162. Name 3 sources of air for starting turbines
    • APU
    • GPU
    • bleed air from running main engine
  163. Do the field or armature windings receive current for starting in a starter-generator?
  164. 2 parts of a starter generator that require periodic inspection for wear
    • commutator
    • brushes
  165. What two types of carburetors are most common to small recips
    • float
    • pressure
  166. What is the function of mixture control of float carburetor
    to control fuel and air mixture
  167. Action of float type carburetor accelerating system when throttle is opened with quick action
    A charge of fuel will enrich mixture in the venturi to help in the transition through RPM range.
  168. When does a carburetor economizer needle begin to open?
    60 - 70 % of throttle position
  169. What is the purpose of economizer system
    Additional fuel at high power for cooling and to prevent detonation
  170. Where does a pressure injector carburetor obtain fuel pressure
    Engine driven fuel pump
  171. What operates automatic mixture control?
    A sealed bellows that expands and contracts with change in pressure or temperature
  172. What is the position of pressure injector carburetor manual mixture to stop engine?
    Idle cutoff
  173. Three advantages of direct fuel injection
    • less danger of icing
    • improved acceleration
    • improved distribution
    • reduced overheating
    • better fuel economy
  174. Problem caused by excessive rich mixture at idle
    Plug fouling
  175. What is the indication of proper idle mixture at cutoff
    Slight rise in RPM before stopping
  176. Why accelerate periodically while making adjustments?
    Clean out engine
  177. Function of turbine engine fuel controls
    Automatically satisfy engine needs
  178. Name two basic turbine fuel controls
    • Hydro mechanical
    • electronic
  179. Variables detected by turbine fuel control
    • power lever position
    • engine RPM
    • compressor inlet temperature
    • compressor inlet pressure
    • compressor discharge pressure
    • burner pressure
  180. Two sources used for fuel heating (turbine)?
    Bleed air and engine oil
  181. What turbine engine components inject fuel into combustion area
    Fuel spray nozzles
  182. Name another type of fuel metering system other than carburetors
    Direct fuel injection
  183. Trimming is accomplished by one of two ways, what are they?
    • EPR
    • RPM
  184. Name two major components of a supervisory electronic engine control
    • ECU
    • Hydro mechanical fuel control
  185. What maintenance adjustments are allowed on a hydro mechanical fuel controls
    • Fuel specific gravity
    • idle RPM
    • Maximum RPM (EPR)
  186. Name two advantages of FADEC
    • No trimming
    • better starts
    • saves fuel
    • provides limit protection
    • constant idle speed with changes in atmosphere and bleed air
    • fully modulates the active clearance control
    • more repeatable engine transients
  187. What is the purpose of turbine engine driven fuel pump
    Continuous supply of fuel at the proper pressure at all times
  188. Two categories of turbine engine fuel pumps
    constant and variable displacement
  189. What type of pump is a gear type pump
    constant displacement
  190. What keeps a dual element constant displacement fuel pump operating if one gear seizes
    Shear sections on shafts
  191. What happens to excess fuel not required by the engine in a CD pump
    Pressure valve bypasses excess fuel
  192. What type of pump that can vary amount of fuel regardless of speed
    Variable displacement pump
  193. What is the purpose of the pressure portion of P&D valve
    Provide primary and secondary fuel flow to dual line duplex nozzles
  194. What is the purpose of the dump in the P&D valve
    Drain fuel after shut down
  195. Type of pump is widely used other than gear and piston
    Rotary vane
  196. What is the purpose of fuel boost pumps?
    Supply fuel under pressure to engine drive pumps.
  197. Boost pumps prevent what?
    Engine driven pump cavitation and vapor lock.
  198. Name the most common type of boost pump
    Centrifugal pump
  199. Causes of vapor lock
    • low pressure
    • high temperature
    • excessive fuel turbulence
  200. Why is vapor lock serious
    Fuel flow blockage can result
  201. What is the purpose of of main fuel strainers
    Collect water and sediment and keep foreign matter out of carburetor
  202. What unit in a turbine engine system is susceptible to ice
    Fuel filter
  203. Purpose of fuel selector valves
    • stop fuel flow
    • tank and engine selection
    • cross feed and transfer
  204. Safety feature in an engine fuel system micron filter
    A bypass valve
  205. Methods used to prevent ice in turbine fuel filters
    Heat exchangers using bleed air or engine oil
  206. What does the divided fuel flows of a turbine engine duplex fuel nozzle produce in the fuel?
    Two spray patterns
  207. What is looked for during an external inspection of engine driven fuel pump?
    Leaks and mounting security
  208. Name three units in a reciprocating induction system
    • carburetor
    • air scoop
    • intake
  209. What is the result of induction icing?
    Power loss and erratic operation
  210. Name three classes of induction ice
    • impact ice
    • fuel evaporation ice
    • throttle ice
  211. What is the common method of preventing induction ice
    Heat induction air with pre-heater.
  212. Causes of fuel evaporation ice?
    Decrease in temperature caused by fuel evaporating in air stream
  213. When is throttle ice most likely to form?
    During part throttle operation
  214. Name two types of supercharged induction systems
    • internally driven
    • externally driven
  215. Function of a sonic venturi in a turbo charger system
    Limit amount of airflow used for cabin pressure.
  216. How does an internally driven super charger boost?
    Impeller compresses the fuel air mixture after the carburetor
  217. Where does the externally driven supercharger derive its power
    Exhaust gases directed against some form of turbine (turbocharger).
  218. Function of a waste gate?
    Controls amount of gases directed into turbine of a turbo charger
  219. Indication of leaking intake pipes
    Engine runs rough at low RPM.
  220. What is an indication of induction system obstruction
    Fails to start or low power
  221. What is an indication of waste gate not fully closing
    Aircraft may not reach critical altitude
  222. Probable cause of turbo charged engine surging?
    Waste gate or controller malfunction
  223. What is used for waste gate actuator power?
    Oil pressure
  224. Indication of carburetor heat application
    Noticeable loss of power
  225. What is the danger of applying carburetor heat at high power?
  226. What is an indication of dirty air inlet filter?
    Loss of power
  227. How does the divergent shaped air inlet affect the air flowing to the engine in supersonic flight?
    Air velocity decreases, pressure increases
  228. Bell mouth inlets are used on what aircraft?
  229. How does an IPS work?
  230. Name two methods used for anti ice on inlet ducts
    Bleed air and electric elements
  231. Name three reasons excessive heat is undesirable?
    • Affects combustion
    • Weakens and shortens engine life
    • Impairs lubrication
  232. What provides cooling surface area on reciprocating engines?
    Cooling fins.
  233. What happens to heat after it's transferred to cooling fins?
    Transferred to the air.
  234. What is done with a cylinder with excessive broken fins?
  235. What is the principal function of cowling and baffles?
    Direct air flow over cylinders.
  236. What controls the amount of air flow through the cooling area of a reciprocating engine?
    Cowl flaps.
  237. What is an augmentor cooling system?
    Uses exhaust gases to draw cooling air using a venturi.
  238. What power is used to operate cowl flaps?
    • Manual
    • Electric
    • Hydraulic
  239. Why use augmentors?
    Provide extra cooling.
  240. Where should cowl flaps be positioned during ground ops
  241. Information needed prior to re-profiling a cooling fin?
    Manufacturer recommendations.
  242. Functions of engine cowl?
    Streamlines and cools engine.
  243. What is the purpose of cowl air seals?
    Force air to circulate around and through the baffle system.
  244. Why is cowl flap adjustment important?
    Must be in tolerance to keep CHT in check.
  245. Where must most cooling air flow to cool a turbine?
    Through engine
  246. What areas are cooled by air passing through the engine?
    Combustion chamber and turbine section.
  247. Source of bleed air vented turbine engine bearings and parts in some engines?
    Compressor section.
  248. What percentage of air is moved through turbines for cooling?
  249. What is the relationship in turbine engines to heat and power?
    Higher the heat, higher the power.
  250. How is bleed air used to allow higher temps in the turbine section of some engines?
    Bleed air is ducted through hollow inlet IGVS and hollow first stage rotors, keeping them cool enough to prevent damage.
  251. How are high temperature gases removed and disposed of in a reciprocating engine?
    Engine exhaust system
  252. What is the primary function of exhaust system (safety)?
    Protects airframe from destructive exhaust gases.
  253. Name two types of reciprocating engine exhaust systems.
    • short stack
    • collected systems
  254. What type of exhaust systems are used on turbo charged engines?
  255. Material used to make exhaust shrouds?
    Stainless steel
  256. What draw back is overcome using collected system and turbo charging?
    The loss of power due to back pressure.
  257. Why is exhaust failure considered a hazard?
    Results in carbon monoxide poisoning, power loss, or fire.
  258. Why should lead, zinc, or galvanized marks not be made on exhaust systems?
    Marks cause a change in the molecular structure of the metal when heated and causes cracks
  259. Indication of exhaust leaks?
    Flat gray or sooty black deposits.
  260. How are internal baffles and diffusers inspected?
    Disassemble as needed to thoroughly inspect.
  261. What can result from failures of diffusers or baffles?
    Restriction of the flow of gases.
  262. What happens when a heat exchanger leaks exhaust gases into the intake system?
    Loss of power.
  263. Where are exhaust manifold and stack failures usually found?
    Welded or clamped joints or flanges.
  264. Name the common cause of turbo waste gates sticking.
    Coke deposits or carbon build up.
  265. Why are turbo exhaust leaks very damaging at high altitudes?
    Pressure differential causes leaks with torch like intensity.
  266. What are coke deposits?
    Carbon build up.
  267. What happens to turbine performance if the exhaust nozzle area is changed?
    Performance and EGT changes.
  268. Components of a typical turbine exhaust nozzle?
    • Tail cone
    • exhaust duct
    • support struts
  269. Function of a thermocouple probes in a turbine exhaust tail pipe
    Measure EGT
  270. What change goes a noise suppressor make on a turbo jet engine?
    Converts low frequency to high frequency.
  271. What are thrust reversers used for?
    Decelerate after landing.
  272. Name two types of thrust reversers
    • Mechanical (clamshell)
    • Cascade (aerodynamic)
  273. Do thrust reversers equal engine thrust?
    No, much less.
  274. What are the hazards of reverser operations at low speed?
    • Re-ingestion of hot gases
    • FOD damage
  275. How do you determine repair ability of propellers?
    Manufacturer maintenance manual.
  276. What is the purpose of props?
    Blades produce a force.
  277. What is a fixed pitch prop?
    Built in blade angle that does not change.
  278. What would be the blade angle change during a constant power drive (governer controlled)?
    Increased blade angle to prevent over speeding of the engine.
  279. Other than maintaining constant speed, what are two actions of a controllable prop?
    • Reverse
    • Feather
  280. What is the purpose of metal tipping on wooden propellers?
    Protect propellers leading edges.
  281. When an engine vibration is reported, what should be checked?
    • Blade tracking
    • Blade angle
  282. What is blade tracking?
    Determine blade tip positions in relation to each other.
  283. What is used to check blade angles?
    Propeller protractor.
  284. How should aluminum blades be cleaned?
    IAW manufacturer recommendations.
  285. Name the two positions to balance props?
    Horizontal and vertical.
  286. What two forces are balanced in a propeller governor in an on speed condition?
    Speeder spring and fly weight.
  287. Effect of centrifugal force on light prop counter weights?
    Increase propeller pitch.
  288. What happens if constant speed feathering propeller when prop governor oil pressure drops to 0?
    Propeller will feather.
  289. Name three things a typical Constant Speed Propeller governor accomplishes?
    • Boosts engine oil pressure before it enters propeller hub
    • controls oil flow into propeller
    • senses rotational speed of engine.
  290. Systems used to control ice on props?
    Fluid (alcohol) or electrical (boots)
  291. What NDT should be done on propeller after blending?
    MANU RECS Manufacturer recommendations.
  292. What terms do "alpha" and "beta" range refer to?
    Operating modes of turbo prop reversible-pitch propellers.
  293. Define alpha range
    Operational in constant speed mode (usually in flight).
  294. Define beta range.
    Zero or minimum thrust and negative thrust (ground handling or taxi).
  295. What is the purpose of oil accumulator connected to propeller governors?
    Provide unfeathering oil pressure.
  296. How is feathering accomplished on a CSP?
    Releasing oil pressure allows counter-weights and feathering spring to feather prop.
  297. Criteria used to determine amount of bend damage that can be repaired?
    Extent of damage and blade station.
  298. What is used to remove file marks from a propeller?
    Very fine sandpaper.
  299. What is used to clean wooden propellers
    Mild soap and water and brush
  300. What does APU stand for
    Auxiliary power unit.
  301. Define APU
    A small turbine with provisions for bleed air and electrical generation.
  302. What causes the greatest demand on APUs?
    Bleed air loads.
  303. What is the function of an APU?
    • Electrical power
    • pneumatic power
    • back up source of electrical power
  304. What is typically used to start APU
    Its own electric starter and battery
  305. What speed does a turbine APU operate?
    At or near rated speed regardless of load.
  306. How is a heavily loaded APU nearing its max (EGT) protected?
    Load control valve.
  307. How is the cool down for many APUs done?
    Running for a specified time after closing the bleed air valve (unloaded).
  308. Where does an APU get its fuel supply?
    One of the main air fuel tanks.
  309. What does the cool down time do?
    Stabilizes EGT.
  310. APU speed is maintained by?
    Fuel control (automatic).
  311. Name 2 uses for APU pneumatic power?
    • Engine start
    • a/c
    • anti-icing
  312. What is the cause of thermal shock?
    Shutting down loaded or no cool down period provided.
  313. What powers the IGVs on APUs?
    Fuel pressure.
  314. Typical cool down period for APUs?
    3 minutes.