AE-1252 Aircraft systems and Instrumentation
Short
Questions
1) Name any four
modern control systems?
- Fly by wire (computer):- May be
Analog computer or digital computer
- Fly by optics (light):-
- Power by size (user
electro-hydraulic actuators
- Intelligent flight control system
2) What do you
mean by active control technology? Give at least three examples?
Activate control technology helps to
improve the handling of aircraft and to reduce the time lag or control delays
by increasing the no. of computers, etc., in the aircraft (i.e. redundancy).
This advance concept in applicable to following e.g..
Examples are:-
-
Fly by wire
-
Control configured vehicles
-
Automatic flight control
system.
3) Name any four communication
system?
HF (High Frequency) communication for long
range
-
VHF (Very High Frequency)
communication for short range
-
Sat Com (Satellite Communication)
-
ACARS/AIRCOM
4) Name any four
navigation system?
-
VHF Direction Finder (VDF)
-
NDB
-
ADF
-
GPS
5) What is INS
used for?
Ins (Inertial Navigation
System) is a sophisticated system for continuously calculating the aircraft
track, ground speed and then convert this information in to other useful data.
6) Differentiate
between instrument landing system and Microware landing system?
-
In MLS, the A/C can approach
from different directions, rather than having to fly to a position on the extended
centerline of the run Cray in use.
-
MLS guidance is more accurate
than ILS.
-
MLS increases the no. of A/C that can approach at name time.
7) What do you
mean by VOR & CCV?
VOR means (Very High Frequency Omni
range)
(Ref. to your
notes as text book)
CCV means
(Control configured Vehicle)
(Ref. to your
care study)
8) What is ADF
& NDB?
-
ADF means automatic direction
finder
(See notes or Text book)
-
NDB mean non directional
beacons
(See notes or text book)
9) What is SELCAL
& Sat Con?
See notes
10) Differentiate
between electric trim and manual trim?
Electric trim is usually used to
reposition stabilizer. Manual trim is used to override the elective trim.
11) What is
difference between speed brakes and spoilers?
Speed brakes are used for
reducing the speed of A/C by increasing the drag. They also act as spoilers to
spoil the lift
Spoilers are used
to spoil the lift for descending or landing.
12) Name any four
control system components?
-
Bell
-
Walking beam
-
Sector & Quadrant
-
Torque tube
13) What is
stabilators, ruddervators and flaperons?
STABILATOR = STABILIZER + ELEVATOR
(MOVABLE)
RUDDERVATORS = RUDDERS +ELEVATORS
FLAPERONS = FLAP + AILERONS
14) What is
aileron differential control system?
Movement of control stick moves
one ailerons up greater than the other down words.
15) What is the
use of yaw dampers in rudder control system?
Yaw damper systems operate
continuously in flight to improve the airplane’s directional stability and turn
coordination. Dampers actuators are powered hydraulically.
16) What are the
merits and demerits of analog and digital fly by wire flight control system?
See notes
17) Differentiate
between fly by wire and conventional system?
See notes
18) How are cable
tensions measured?
Tensometer
19) Name some
advantages of fly by wire control systems?
-
Weight saving
-
Improved handling
-
Fuel saving
-
Reduced maintenance
20) Classify at
least truce engine control system?
-
FADEC (Full Authority Digital
Electronic/Engine control)
-
ECU (Electronic Engine Control)
ECU can be manually over ridden by FADEC can not (For details see
notes)
21) What you mean by heat exchanger?
A heat exchanges is
any device by which heat in transferred from one independent system to another
independent system.
(See notes for
details)
22) What is thermal relief value?
A thermal relief
value is similar to a regular system relief value bit such values are installed
in parts of the hydraulic system where fluid pressure is trapped and may need
to be relieved because of the increase caused by higher temperatures.
(Refer
notes of power pack for details)
23) Differentiate between single-acting and double acting actuating
cylinder?
A single
acting actuator is normally used as a locking device the lock being engaged by
spring pressure and released by hydraulic pressure.
The double
acting actuator is used in most aircraft systems eg landing gear.
24) Differentiate between capon and closed hydraulic system?
An open
system is one having fluid flow but no appreciable pressure in the system
whenever the actuating mechanisms are idle. Its simple but only one service can
be operated by this system at a time.
(For diagram see notes)
A closed system is one that directs
fluid flow to the main system manifold and builds up pressure in that portion
of the system the leads to all the selector values. Its bit complicated but
more than one service can be operated by this system at a time.
25) Classify air pressure sources?
-
Super charger
-
Turbo charger
-
Engine bleed air
-
Independent cabin compressors
26) What is a
moisture control?
The great reduction in temperature
causes the moisture in the air to condense and thin moisture is removed by
means of a water repeater.
(For details
see notes)
27) Differentiate
between springs oleo struts and air oleo struts?
In spring oleo struts, the spring
supports the A/C weight on the ground and during taxiing and oleo strut aborts
the shock of landing.
In air oleo struts, the air supports
the A/C weight on the ground and abserts shocks during taxiing and oleo strut
aborts the shock of landing.
28) What is
trunnion?
The trunion is the portion of
landing gear assembly attached to the airframe. The trunnion in supported at
its ends by bearing assemblies which allows the gear to pivot during retraction
and extension.
29) Explain the
difference between dray strut and side strut?
Draglink or drag strut is designed
to stabilize the landing gear assembly longitudinally. Side link or side
assembly laterally.
30) Classify the
types of retraction system?
-
Mechanical retraction system
-
Electrical retraction system
-
Hydraulic retraction system
31) What is
bungee cylinder used in landing gear? What is artificial bungee?
The bungee cylinder: are
mechanically linked to side brace links. They are hydraulically actuated & help
in retraction of landing gears.
Artificial bungee: gives feel
factor to the pilot (for details see notes)
32) Differentiate
between sequence and debooster value?
See notes or solved Q paper of Anna University
33) What is ply
rating?
Ply rating is an index of tire
strength. The term is used to identity a given tire with its maximum
recommended load. The higher the rating, the greater the load a tire will
carry.
34) Differentiate
between expander – shoe brake and expands – tube brake?
Expander shol brake: Relation of break
drum adds braking energy to the break shoes and makes them operate more
effectively & with Len effort by the pilot. They are also known as serve
brakes.
Expander tube
break: The pressure of hydraulic fluid in the tube forces the blocks radically
outward against the break drum.
35) Differentiate
between single disk brake and multiple disk break?
Single disk brakes are used in
smaller aircraft single disk may be conducted with an many separate pistons and
linings as needed for the airplane. Each piston in equipped with separate sets
of linings, which bear against the brake disk when the brake see applied
multiple disk brakes are used in large aircraft. Braking action is produced by
hydraulic pressures forcing the pistons against the pressures plate, which, in
turn, forces the disk together and creater friction between the reetratiny and
stationary disks.
36) Differentiate
between segmented reetear disk brake and carbon composite brakes?
Segmented rater disk brakes are heavy
duty brakes designed for use with high pressure hydraulic systems using power
brake control values or power boost master cylinders. Braking action results
from several sets of stationary linings making contact with rotating segments
Carbon composite
brakes: In this the disks are made of carbon. Its long-life, light weight
compared to steel brakes and more reliable.
37) Classify A/C
break system & Landing gear?
A/C Brake systems are: Landing
gear
-
Independent brake system - Non
absorbing landing gear
-
Power boost system
- Shock absorbing landing gear
-
Power brake system
- Fixed gear
-
Multi power brake actuating
system - Retractable
landing gear.
38) What is a
master cylinder?
The master cylinder in the
energizing unit. There is one for each main landing year wheel. It is a feet
operated single action reciprocating pump, the purpose of which is to build up
hydraulic fluid pressure in the brake system.
(for diagram see
notes)
39) What do you
mean by anti skid system?
Anti skid system are used to
prevent loss of airplane control on the ground caused by skidding of the
wheels. The system consists of electronic controller, transducers, servo
values, indicating light & switch.
(See block diagram
from notes)
40) What are the
advantages of pneumatic system over hydraulic system & voice versa?
(See notes as Anna University
41) What is surge
fuel tank?
Surge fuel tanks are normally empty
and are designed to contain fuel overflow & prevent fuel spillage
particularly when fueling the aircraft.
(Far diagram see notes)
42) What do you
mean by ‘wet weinj’?
An integral fuel tank is a tank that in
part of the basic structure of the aircraft. When as integral type of tank is
used in a wing, the air craft is said to have a “wet wing”
43) What is vapor
lock?
Vapor lock is a condition of fuel
starvation that can occur in a reciprocating engine fuel system in which the
fuel in the fuel line is heated enough to cause it to vaporize, forming a busle
of fuel vapor in the lime blocking fuel from flowing to the engine.
44) a) Classify
fuel system? b) Why do we need primers?
a) Fuel systems are
- Gravity feed fuel system
- Pressure feed fuel system
b) Non fuel injected reciprocating
A/C engines must often be primed before starting because carburetor is not
functioning properly until the engine is running
(Fer
diagram see notes)
45) What is fuel
cross feed system?
On most multiengine air craft, the
fuel manifold are connected in such a manner that any fuel tank may supply fuel
to any engine, any tank can transfer fuel to other tank for balancing.
(for diagram see notes)
46) What is fuel
Jettirson or dumping system?
In this system fuel from the
tanks is continuous from using tip to using tip, with each end terminating at a
fixed fuel jettison nozzle. The nozzle value is an electrically ape rated value
controlled from the cockpit. After fuel passer through the nozzle value, it flows
into the jettirson nozzle to be discharged in to the air the jettison nozzle to
be discharged in to the air.
(for diagram see notes)
47) What is
difference between defueling and jettison?
Defueling means draining the
fuel out of the tanks when A/C is on ground. Jettison means dumping the fuel
out of tank when A/C is in air fuel in dumped at the time of emergency landing.
48) What is the
purpose of fuel boost over ride & scavenge pump in fuel system?
The central using tank boost
pumps will over ride the main-tank boost pump to supply fuel through the
manifold to the engines. That’s way its known as fuel –boost-over ride pump.
Scavenge pump
helps to prevent water from accumulating in the tanks low points. Thus avoids corrosion
problems.
49) How will you
select the starting system of the A/C?
(See chapter 5 Engine starting system in A/F
& power plant for details)
50) Enumerate the
lubricating systems used jar jet engine?
-
Drug sump Lubrication: utilize
an external tank mounted on the engine or some where in A/C structures near the
engine.
-
Wet sump Lubrication: stores
the lubricating oil in the engine proper.
51) Differentiate
between fuel system of piston and jet engines?
(See notes for details)
52) How does
scavenge system work in lubrication?
The scavenges system scavenges the
main bearing compartments and circulates the scavenged oil to the oil coolers
and bock to the tank.
53) What is
breather pressurizing system?
The breather pressurizing system
ensures a proper oil spray pattern from the main bearing oil jets and furnishes
a pressure head tee scavenge system. Breather maintains an oil system pressure.
It prevents over pressurizing.
54. Clarity turbine engine ignition system?
54.-
Capacitor type ignition system(jet)
- Electronic ignition system (jet)
- Battery ignition system P
- Magnetic system (High tension)
- Magnetic system (Low tension)
55. Clarity gas turbine engines starting
system?
55. - Direct cranking electrical system
-Starter generator systems
-APU (Pneumatic) systems (see page 274 fees details)
56. Clarity reciprocating engine starting
system?
56. – Cartridge starter
- Hand inertia starter
- Electric inertia starter
- Come inertia starter
-Direct cranking starter
57. What is ignition exciter?
57.(See notes)
58. Draw a neat diagram of typical
electronic ignition system?
58. Fig 4.77 page 233 at power plant hand
book.
59. Differentiate between nigh tension ignition
system & low tension ignition system?
59. Magneto Ignition system operate on the
principles of electro magnetic induction. They can be high tension & low
tension ignition system.
- High tension magnetic Ignition system High voltages are induced either
by rotating the transformer windings between poles of permanent magnet or by rotating
the magnet between fixed transformer windings car by rotating soft iron bass
between fixed permanent magnets and transformers winding.
-
Low tension magnate Ignition system then system were developed far engineer
having large no of better then high tension. In this, the low voltage impulses
from the magneto primary are directly supplied to the distributor. The low
tension magnet are suited on and off similar to the high tension magneto. (See
figure 4-16 & 4-17 for low tension magnets) [In your text book A/F &
power plant]
60. Draw a neat diagram of hydro mechanical
fuel control?
60. See notes car see page 157 of power
plant hand book.
61. What do you mean by environmental
system?
61. Environmental systems are there
aircraft systems used to make they interior environment of the aircraft comfortable
and/or habitable for human beings.
62. What is bleed air?
62. When a compressor, compresses air price the directory it the
engine combustion chamber, it gets heated up. This heat compressed air is called
bleed air, which can be driven to a cabin heating system.
63. What are A/C cooling system or air
conditioning systems?
63. Air craft cooling system are used to reduce
the temperature inside and aircraft for crew and passenger comfort. The two
basic methods of reducing the temperature are the vapor. Cycle machine and the
air cycle machine.
64. What is air cycle and vapor cycle
machines?
64. Air cycle machine:- The turbine,
compressor unit by which air is cooled is called air cycle machine(ACM) The ACM
user compression and expansion of air to lower the temp. of cabin air.
Vapor cycle machine: - User refrigerant
instead of air The vapor cycle machine in a closed system usury the evaporation
and condensation of freon to remove heat from the cabin interior
65. What do you mean by purging the system?
65. In vapor cycle refrigeration system,
purging means releasing the refrigerant.
In fuel system, purging means draining the
fuel from tank by introducing inert gas as co2 ar N2 to the tank.
In oxygen system, purging means releasing oxygen
from the system.
66. What is shirt sleeve environment?
66. In order to make the cabin environment
comfortable for the air craft occupants, the cabin must normally be pressurized
to maintain the cabin air pressure at the level reahed at no higher than 800
it. This enables the crew and passengers to function without the uses of supplemental
oxygen and, with adjustments of the cabin air temperature, allows them to be in
a shirt sleeve” environment.
67. Differentiate between super changer and
turbo charger?
67. A supercharger is an engine drive air pump;
mechanically drive for engine, which compresses air for use by the engine in
the combustion process.
A turbocharger is used in a similar manner
as a system charger except that the turbo charger is driven by exhaust gases
from the engine, which driver an air compressed to supply an air charge to the
engine.
68. What is out flow value, safety or relief
value, and negative pressure relief value?
68. –Out flow value are discharge value
- Pressure relief value x used at high altitude to reduce the over
pressure.
- Vacuum Relief values so negative or relief values are used at low
altitude or ground in car the pressure in cabin in lem than out ride pressure
69. What is a cooling pack?
69. Cooling packs consist of primary heat
exchanger, secondary heat exchanger and air – cycle machine (turbine &
Comprenor). They are used to cool the air
70 What is boot strap arrangement?
71. Differentiate between hypoxia and
anoxia
71. Hypoxia ÷ A lock of oxygen causes a
person to experience a condition called hypoxia. Systems are headaches, dizzimens
etc.
Anoxia ÷when permanent physical damage
results from lack of oxygen, the condition is anoxia.
72. Clarity oxygen system?
72. – Continuous flow oxygen system.
- Diluter Demand system
- Pressure Demand system
- Stored gas system
- Chemical oxygen Generator or solid state generator system
- liquid oxygen system(LOX)
73. Write the chemical reaction in chemical
oxygen or solid state generators?
73. Naclo3 + Fe →Nacl + FeO + 02↑
(Fuel)
(See Fig. From Notes)
74. What are auxiliary systems?
74. Systems not essential to the actual
operation of the Aircraft are called auxiliary System.
75. What ways can ice be detected?
75. -Visual detection
-Electronic instrument
76. What is de-icing?
76. De-icing means removing ice that has
already farmed.
77. What is thermal anti-icing?
77. Thermal anti-icing heated air flowing through
passages in the leading edge of wings,
Stabilizers
and engine cowlings tee pre unit the formation of ice.
78. What is wind shield ice control?
78. –By heating the wind shield
-By spraying a fluid on the windshield, to remove ice and present the
formation of any more ice
79. What is gasper system?
79. The individual air- distributive
system, also called the gasper system, reutes only the cold air from the air
conditionary packs to individually regulated outlets in the control and
passenger cabins.
80. Name any three values used in pressurization
system components?
80. –Out flow value
- Positive pressure relief value
- Negative pressure relief value
81. What is static balancing?
81. To eliminate the effect of cross wind
or side slip the static resource in duplicated and is known as static
balancing.
82. Evaluate “TAS”?
82. –CAS= IAS+PEC
-EAS= CAS+CEC
-TAS= EAS+OEC (See notes fees details)
83. How is mach no. is inversely related to
temperature (See notes for details)
84. What is the principal behind vertical
speed indicator?
84.
85. What is difference between SAT and TAT?
86. SAT(Static air temperature) –This is
the tem the air at the surface of the aircraft would be at if there were no
compression effects due to air craft is movement TAT (Total air temperature) in
the temp. Of the air when it has been brought completely to set , as in the
pilot tube.
.
87. The turn and bank indicates uses which
of these :-Free gyro /tied gyro/ Earth gyro/ rate gyro.
87. Rate gyro.
88. How is gyro powered?
88. Electrically & Pneumatically.
89. Name any three electronic display
systems?
89. –Electronic height Instrument system
(EFIS)
- EICAS (Engine indicating and crew alerting system)
-ECAM. (Electronic centralized air self monitoring)
(For details see notes)
What is flight management system?
90. Draw a block diagram of typical FMS
(Flight management system)
90. FMS in a “Pilot – interactive
navigational com putting and display systems designed to assist in flying an
air craft with the maximum economy and safety to a previously planned route defined
both laterally and vertically.
91) What is TCAS?
Traffic collision Avoidance system
92) Show black diagram of flight data
recorder?
93) Show black diagram of cockpit voice
recorder?
94) What is BITE?
BITE means Build In Test Equipment. BITE is a fault management and diagnosis’s
built into airborne systems to support the maintenance process.
95) What do you mean by AIDS & ACARS?
ACARS Aircraft Communication Addressing and
reporting system (see notes for detail)
AIDS: Air craft integrated data system is
an A/C system that allows the airlines to record and /or monitor all available
parameter which are on the aircraft buses.
96) What are the units of fuel consumption
gauge?
Fuel flow is:
-
Volumetric i. e gallons or
liters per hour
-
Man \flow i.e. pounder (lb) or
kilogram per hour.
97) How can use measure RPM of engine?
-
By Electronic Tachometer
-
By electrical Tachometer
-
By Magnetic Tachometer
98) What is multipurpose display?
The multipurpose display is used for monitoring and revising the flight
plan.
99) Explain the principle of Magnetic composes?
It works on the principle that a freely suspended magnet will align
relay with the eartin magnetic filed such that one end will point toward the
north magnetic pole.
100) what is the purpose of artificial
horizon?
Artificial horizon (also known as attitude indicates) is used to to
provide the pilot with an indication of the aircraft attitude in both pitch and
roll.
Long
Questions
1)
What are the functions of push
pull and flexible push pull red system? Explain with neat diagram?
2)
Explain how fully powered
flight control system and power boated flight control system work?
3)
Explain the merits (advantage)
and demerits (disadvantage) of analog and digital fly by wire flight control
system?
4)
Explain the working and the
advantage of auto pilot system?
5)
Explain INS, ILS, MLS, VOR,
ADF, NDBR selcal communication with neat diagram?
6)
Explain the working of any two
Engine control system with neat sketcher?
7)
Explain sequence value, Debooster
value, relacter value, shutt off value Cressfeed value?
8)
Explain with neat diagram the
working of typical hydraulic far B-727 cross feed value?
9)
Explain shimmy dampers in rose
gears Air-oleo spring oleo shock struts in main landing gears?
10) Clan its airbrakes? Describe Expander tube brake system explain its
working?
11) Differentiate between fuel system of piston and jet engine?
12) Explain lubrication system used for piston and jet engine? Also
explain electronic engine control?
13) Explain the starting system for the A/C? List out the gar turbine
engine starters explain with neat diagram?
14) Describe the fuel system for B 747 A/C with neat diagram?
15) Explain high & low voltage capacitor type ignition system.
16) Explain with neat sketcher the air cycle cooling system and vapor
–cycle cooling system of an A/C
17) Explain icing do-icing and anti -icing? Discus pneumatic de-icing
system?
18) What are cooling pales? Explain?
19) Explain the working of different fire detection and smoke detection
techniques used in A/C with neat sketches?
20) Classify different type of oxygen system? Explain solid state oxygen
systems? Write down its advantages?
21) Explain the following with neat diagram:
-
Accelerometer
-
Capacitance type fuel level
indicator
-
Flight data recorder
-
Thermocouple
22) Explain the working of following with neat diagram:
-
Electrical tachometer
-
Altimeter
-
Airspeed indicators
-
Mach meter
23) Explain with neat diagram
-
Gyroscopic instrument
-
Resistance type temperature
measuring system
-
Magnetic tachometer
-
EHS & EAS relation
24) Explain the functional
-
Multi function display (MCDU)
-
EFIS
-
EADI & EHSI
-
EICAS & ECAM
25) Explain with neat diagram
-
Bank indication (Turn &
back indicator display)
-
Heading indicates
-
Attitude indicates
-
Turn coordinator
