Powerplant: Engine Instrumentation
A bourbon-tube instrument may be used to indicate
1. pressure and 2.temperature.
Which of the following instrument discrepancies require replacement of the instrument?
2.glass cracked 4.will not zero out 5.pointer loose on shaft 8.fogged.
Which of the following instrument conditions is acceptable and does not require immediate correction?
5. case paint chipped
Instruments that measure relatively high fluid pressures, such as oil pressure gauges, are usually what type?
Bourdon tube.
Which of the following types of electric motors are commonly used in electric tachometers?
Synchronous motors.
In addition to fuel quantity, a computerized fuel system with a totalizer-indicator provides indication of how many of the following?
Three
what would be the possible cause if a gas turbine engine has high exhaust gas temperature, high fuel flow, and low RPM at all engine power settings?
Turbine damage or loss of turbine efficiency.
The indication on a thermouple-type cylinder head temperature indicator is produced is produced by
a current generated by the temperature difference between dissimilar metal hot and cold junctions.
The fuel-flow indicator rotor and needle for a motor-impeller and turbine indicating system is driven by
an electrical signal.
In an aircraft equipped with a pressure-drop type fuel-flow indicating system, if one of the injector nozzles becomes restricted, this would cause a decrease in fuel flow with
an increased fuel flow indication on the gauge.
thermocouple leads
are designed for a specific installation and may not be altered.
An indication of unregulated power changes that result in continual drift of manifold pressure indication on a turbosupercharged aircraft engine is known as
bootstrapping.
(1) Powerplant instrument range marking show whether the current state of powerplant operation is normal, acceptable for alimited time, or unauthorized. (2)Powerplant instrument range marking are based on installed engine operating limits which may not exceed (but are not necessarily equal to) those limits shown on the engine TCDS
both 1 and 2 are true
(1)Generally, when a turbine engine indicates high EGT for a particular EPR, it means that the engine is out of trim (2)Some turbine powered aircraft use RPM as the primary indicator of thrust produced, others use EPR as the primary indicator.
both are true.
Jet engine thermocouples are usually constructed of
chormel-alumel
instruments that provide reading of low or negative pressure, such as manifold pressure gauges, are usually what type?
diaphragm or bellows.
Engine pressure ratio is determined by
dividing turbine outlet total pressure by engine inlet total pressure.
A common type of electrically operated oil temperature gauge utilizes
either a wheatstone bridge or ratiometer circuit.
What instrument indicates the thrust of a gas turbine engines?
engine pressure ratio indicator.
The engine pressure ratio indicator is a direct indication of
engine thrust being produced.
Engine oil temperature gauges indicate the temperature of the oil
entering the engine
The RPM indication of a synchronous ac motor-tachometer is governed by the generator
frequency
basically, the indicator of a tachometer system is responsive to change in
frequency.
engine pressure ratio is the total pressure ratio between the
front of the compressor and the rear of the turbine.
Which unit most accurately indicates fuel consumption of a reciprocating engine?
fuel flowmeter
The fuel-flow indication data sent form motor driven impeller and turbine, and motorless type fuel flow transmitters is a measure of
fuel mass-flow
the fue flowmeter used with a continuous-fuel injection system installed on an aircraft horizontally opposed reciprocating engines measure the fuel pressure drop across the
fuel nozzles
The fuel-flow indication system used with many fuel-injected opposed engine airplanes utilizes a measure of
fuel pressure.
The purpose of an exhaust gas analyzer is to indicate the
fuel/air ratio being burned in the cylinders.
What basic meter is used to indicate cylinder head temperature in most aircraft?
galvanometer.
In regard to using a turbine engine oil analysis program, which of the following is not true?
generally, an accurate trend forecast may be made after an engine's first oil sample analysis
The principal fault in the pressure type fuel flowmeter indicating system, installed on a horizontally opposed coninuous-flow fuel injected aircraft reciprocating engine, is that a plugged fuel injection nozzle will cause a
higher than normal fuel flow indication.
In a turbine engine, where is the turbine discharge pressure indicator sensor located?
immediately aft of the last turbine stage.
A manifold pressure gauge is designed to
indicate absolute pressure in the intake manifold.
Which statement is correct concerning a thermocouple type temperature indicating instrument system?
it requires no external power source.
a change in engine manifold pressure has a direct effect on the
mean effective cylinder pressure.
What is the primary purpose of the tachometer on an axial-compressor turbine engine?
monitor engine RPM during starting and to indicate overspeed conditions.
if the thermocouple leads were inadvertently crossed at installation what would the cylinder temperature gauge pointer indicate?
moves off-scale on the zero side of the meter.
On an aircraft turbine engine, operating at a constant power, the application of engine anti-icing will result in
noticeable shift in EPR
The EGT gauge with reciprocating engines is primarily used to furnish temperature reading in order to
obtain the best mixture setting for fuel efficiency.
Why do helicopters require a minimum of two synchronous tachometer systems?
one indicates engine RPM and the other main rotor RPM.
On a twin-engine aircraft with fuel-injected reciprocating engines, one fuel-flow indicator reads considerably higher than the other in all engine operating configurations. What is the probable cause of this indication?
one or more fuel nozzles are clogged.
(1)Engine pressure ratio is a ratio of the exhaust gas pressure to the engine inlet air pressure, and indicates the thrust produced. (2)Engine pressure ratio is a ratio of the exhaust gas pressure to the engine inlet air pressure, and indicates volumetric effieciency.
only 1 is true.
in what units are turbine engine tachometers calibrated?
percent of engine RPM
A complete break in the line between the manifold pressure gauge and the induction system will be indicated by the gauge registering.
prevailing atmospheric pressure.
which of the following is a primary engine instrument?
tachometer
Where are the hot and cold junctions located in an engine cylinder temperature indicating system?
the hot junction is located at the cylinder and the cold junction is located at the instrument.
A red triangle, dot, or diamond mark on an engine instrument face of glass indicates
the maximum limit for high transients such as starting.
What unit in a tachometer system sends information to the indicator?
the three-phase ac generator.
Which statement is true regarding a thermocouple type cylinder head temperature measuring system?
the voltage output of a thermocouple system is determined by the temperature difference between the two ends of the thermocouple.
The exhaust gas temperature indicator on a gas turbine engine provides a relative indication of the
turbine inlet temperature.
What instrument on a gas turbine engine should be monitored to minimize the possibility of a hot start?
turbine inlet temperature.
Motor driven impeller and turbine fuel flow transmitters are designed to transmit data
using aircraft electrical system power
