General know Flashcards
1
Q
Positive load factor for flaps up
-normal and utility
A
Normal- 3.8
Utility-4.4
2
Q
Load factor for flaps down normal and utility
A
Normal- 2.0
Utility-2.0
3
Q
Semi monocoque structure
A
A light frame work covered by skin usually aluminium
4
Q
Spars on wings do what
A
Carry major loads- upward bend with lift and downward bend when they support fuselage and wing tank
5
Q
Struts
A
Provide extra strength by transmitting some of wing load to fuselage
6
Q
Ribs
A
Provide aerofoil shape and stiffen the skin which is attached to them
7
Q
Torsional pressure
A
Twist
8
Q
what is static electricity
A
when positive and negative become imbalanced or when liquids flow or solid objects rub together
9
Q
bonding
A
a conductor can be earthed by connecting to a earthing plant
10
Q
static wick
A
dissipate static charge into atmosphere to get rid of it
11
Q
ventri tube operated vacuums
A
some aircraft use a venti shapes tube. as air flows through it narrows and speeds up. and pressure decreases
this low pressure will cause air to flow through instrument and spin gyroscope
12
Q
oleo pheunamatic unit
A
move with cylinder against pressure. Move along ground and load varies so strut move up and down
13
Q
torque link
A
used to align nose wheel correctly with airframe
14
Q
nose wheel shimmy
A
when nose wheel oscillates either side of center as plane runs along the ground.
cause if shimmy damper is insufficiently pressurised or torque link failed
15
Q
what is a shimmy damper
A
prevent vibrations
16
Q
pascals law-
A
change in pressure at any point in an incompressible fluid must be transmitted throughout the fluid for equal change everywhere
17
Q
one type of hydraulic fluid
A
mineral based- use din light aircraft.
used with rubber hoses to avoid corrosion
18
Q
one type of hydraulic fluid
A
polyalphaolefins- alternate to mineral based- fire resistant.
Viscosity increase in low temp so limit use in low temps
19
Q
one type of hydraulic fluid
A
phosophate esters-
used in larger jets
with high landing speed
20
Q
differential breaking
A
using each break at a time
use in manouvers
21
Q
normnal breaking
A
use both breaks together
22
Q
static pressure
A
exerted equally in all directions. all molecules are pressing down. doesn’t move and measured through a static vent
23
Q
dynamic pressure
A
extra pressure over static pressure and is moving example wind exert pressure on hand
24
Q
what happens to static and dynamic pressure as airspeed increasee
A
dynamic increase static remain same
25
airspeed is always on the
left hand side
26
ias and tas
isa- aerodynamic airspeed and relate to dynamic pressure
tas- actual speed of plane as it travels through air
27
what happens to TAS and IAS as you climb
TAS will increase and IAS will stay same
28
at 5000ft Tas will exceed Isa by what %
8%
29
At 10,000ft Tas will exceed IAS by what %
17%
30
Problems with Air speed indicator
If pitot blocked ASI will under read in a decent and over read in a climb
if static blocked asi will over read in a decent and under read in a climb
31
how aneroid in altitude indicator works
as you descend aneroid is compressed as air density increase indicating decent vice versa in climb
32
altitude indicator is located on
right side
33
Isa
pressure of 1013.2 hpa
mean sea level temp- 15 degrees
temp decrease 2/1000ft
34
small sub scales allow
various pressure settings to be set this is called datums
35
qnh-
qfe-
-mean sea level
-aerodrome level
36
vertical speed indicator
meaured in 100/1000s ft per minute
covert changes of static pressure to changes in altitude
37
vertical speed indicator is located
bottom right
38
OAT is
outside air temp gauge and is located on upper windscreen made up of bi metallic strips,
As one heats it expands and bends and transfers thermal energy into mechanical energy to move the dial in the plane
39
what is rigidity in space
when a gyro remained in the same direction despite the aeroplane moving around it
40
3 ways to increase rigidity
increase spin speed
increase mass around edge
increase gyro mass
41
precession
if a force is applied to a gyro a change in force by 90 degree further will occur
42
gyroscope effects- motor not running
vertical turns left and right have no effect
43
gyroscope effect motor running- move to right
sharp horizontal movement to right causes plane to drop vertically
44
gyroscope effect motor running- move to left
harm horizontal movement to left caused plane to rise vertically
45
vacuum or electrical gyros
vacuum- draw high speed air in and direct it to rotor blades. if suction low gyro be unstable and respond slow
electrical- gyro start up when master switched on.
46
turn coordinator (plane diagram on it) and indicator
show movement along normal axis
both show rate of turn but coordinator show bank angle
eg rate of turn- 3 degree/ sec= 180 degree/min
6deg/sec=360/2min
low vacuum suction= turn indicator will under read
47
heading indicator
magnetic compass is primary direction indicator. but difficult with changes in flight so we use a Hi (AKA di)
48
Apparent drift-
cause by rotation of earth on its axis
49
re allign mag compass every
10-15 min
50
`errors in a gyro
red power failure- correct suction
check it is alligned with mag compass
51
what directions do compass point to
not to true north/south compasses point to magnetic north/south
52
isogonal
dashed lines joining places with same magnetic variation
53
variation is
the angular difference between true north and mag north at any point
54
deviation
when planes mag compass is not only effected by earths magnetic field but also by the planes magnetic field such as metal components in the plane. Try to keep any personal metal belongings away from magnetic compass in flight
55
what is a swinging compass
should be done by engineers but pilots can advise when it may need to be done.
may be after passing through a magnetic storm or it is a new compass ect
56
mag dip
mags dip to 90 degrees at the poles and 0 degrees at equator.
mags stable at equator and unstable at the polesx
57
mag force can be split into 2 components
horizontal- align compass with mag north
parallel- cause mag to dip
58
accelerating east
centre of gravity is left behind - apparent turn north
59
decelerating east
centre of gravity tries to advance towards south
60
accelerating west
centre of gravity left behind and apparent turn to north
61
decelerating west
appaernt turn to south and C of G advance ahead
62
accelerate north and south
no apparent turns
63
turning through north
acceleration at right angles- undershoot
64
turn through south
overshoot
65
stress analysis
calculation of physical load
66
strain
force and load acts on a material and material experience deformation despite the strenth of force
67
hydraulic powered control surfaces
pilot movement on control collumn cause hydraulic system to operate
if excessive control the aircraft will be damaged so springs fitted to ensure pilot has control
68
low crankshaft
require longer struts (resist compression) for the main wheels
69
Basic principles of piston engine
recepricating engine- number of cylinders which move back and forth
in each cylinder fuel and air is burnt and gas drives piston down coverting chemical to thermal to mechanical energy.
piston connect to shaft and this coverts back and forth motion to power and energy
70
4 stroke engine cycle
1-intake
2-compression
3- power
4- exhaust
71
higher pressure requires what fuel
higher quality fuel to withstand pressure and temp being high
72
compression ratio
ratio of total cylinder volume with piston at bottom of stroke in comparison to clearence volume at top of its stroke
73
TDC AND BDC
-Top dead centre when piston reaches top of its travel and bottom dead centre when piston reaches bottom of its travel
74
stroke
distance piston moves between tdc and bdc
75
valves
inlet- what air mix is taken in- each valve open once in every 2 revs
exhaust- where gases from burning is exhausted
76
ignition
most have dual ignition which is 2 spark plugs per cylinder
77
distributor
turns once in every 4 stroke cycle
78
what to do if starter warning light on
shut down engine and mix idle
79
impulse coupling 2 functions
1-accelerate rotating magnet for a high voltage
2-nprevents magnet from rotating as engine is turned over
80
tachometer
as engine turns so does driveshaft, causes flywi=eight assembly to move and angle to which flyweight moves is related to rpm
81
2 stroke engine
simpler than 4
special ports that act like valves as piston moves up and down
as ignition start piston push down to force mx ito cylinder pushing exjaust gases through port
noisy sometimes intake silences needed
82
induction system
side draught carb- use slide and needle value to regulate air flow in
83
lubtication- oil:fuel
25:1 allow satisfactory lubrication
84
cooling
more heat transfer from engine to water jacket
85
Avgas
contains lead and is environmentally damaging
made in small batches
86
disel
cheper and more environmentally friendly
compression ratios 12:1
87
reason for fuel starvation
-insufficent fuel
-fuel contamination
-ice in carburettor
-incorrect fuel tank
-incorrect use of mix
88
fuel to air ratio=
1:12
89
combustion in cylinders ratio-
rich and lean
rich- 1:8
lean- 1:20
90
mix rich
mix lean
rich-too much fuel- can be use as coolant
lean- little fuel supplied
91
accelerator pump
prevents a weakcut if throttle advanced too rapidly as it could cause too much fuel being supplied causing a lag in power
92
idling system
when idle butterfly ventri closed and fuel not forced
allowed by an idling jet- small vent to allow mixture to mix with air to keep engine idling
93
mixture in a climb
keep rich for climb and excess fuel is used as a cooling agent
94
mixture at cruise
make it lean to regain a better fuel to air ratio
95
mix lean
mix rich
increase rpm
decrease rpm
96
abnormal combustion
when fuel air mix causes flame to advance to combustion chamber increasing pressure and forcing piston don
97
if detonation present
rich mix reduce pressure and increae speed
98
impact/inlet ice
when super cooled droplets land on metal surface ice form
99
fuel ice
fuel enter carburetor vaporises and reduce temp if liquid drops below 0 it will freese
100
throttle ice
fuel air mix accelerates past throttle valve-
decrease static p and temp
101
fuel injection system
creates a correct mixture without carburettor.
102
fuel systems-
store and deliver fuel to carburettor in correct quantities despite condition changes
103
how fuel is used in high wing aircraft
relies on gravity and doesnt use fuel pumps for fuel to flow into carborettor
104
# how is
how is fuel transfered in low wing aircraft
use fuel pump for fuel to enter carburetor
105
priming pump-
used in cold conditions or when engine being stood to pump fuel into carborettor
106
fuel quantity gages
work using direct current
use floats in fuel tanks
if it floats up the fuel is being refulled
107
digital fuel indicators
use variable resistance and covert into a number
108
fuel prssure gage
metal in a c bent shape as pressure increase c will straighten as pressure decrase c will bend
109
fuel flow meter
indicates how well engine performing
use pressure and show fuel flow in gallons/hour
110
when refuling
connect to earth so same electrical potential
111
fuel ratings
on anti detonation policies-
eg- high if it can take compression before detonating
low-detonation likey
112
condensation in fuel over night
if fuel levels low condensationon fuel tank walls can form so better to have full tank
113
oil in plane
needed to prevent friction between 2 metal surfaces sliding over eachother and prevent high temps
also is filtered and removes dirt
114
oil properties
viscous- not too thin or thick
fire-cannot catch fire
not change state or charactoristics
oil gather in sump after work returned to wet pumb by scavenger pump
115
