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ADI 03 > Mod 1 - MET > Flashcards

Mod 1 - MET Flashcards

1
Q

Importance of Met in Aviation

A

Safety, regularity and efficiency of international air navigation.

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2
Q

What affects does Weather have on Aviation?

A

Safety
Economy
Comfort.

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3
Q

Decode WMO

A

World Meterological Office

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4
Q

Decode WAFS

A

World Area Forecast System

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5
Q

Decode WAFC

A

World Area Forecast Centre

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6
Q

Decode RSMC

A

Regional Specialist Met Centre.

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7
Q

Decode MWO

A

Meteorological Watch Office

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8
Q

Decode VAAC

A

Volcanic Ash Advisory Centre

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9
Q

Decode TCAC

A

Tropical Cyclone Advisory Centre.

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10
Q

Decode SADIS

A

Satellite Distribution System.

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11
Q

List sources used to gather Met Data

A 
Wx station (with/without) shelter screen 
Registering balloon
Wx observation on buoy or ship
AMDAR - Aircraft Monitoring Data Relay
Met satellite
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12
Q

List reasons for ISA

A

Establish stds for calibration of instruments
Vertical separation between AC
Comparing power parameters of AC and engines

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13
Q

What is the composition of ISA?

A 
Nitrogen - 78%
Oxygen - 21%
Argon - 0.9%
CO2 - 0.03%
Water - 0%
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14
Q

What is the structure of ISA?

A 
Troposphere
Tropopause
Isotherm
Lower Stratosphere 
Upper Stratosphere
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15
Q

What is the Barometric Lapse Rate in ISA?

A

30’ / 1hPa

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16
Q

What is the Air Density in ISA?

A

1.225kg/m3

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17
Q

What is the height and temperature of the Tropopause?

A

11km

-56.5°C

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18
Q

What is the temperature Gradient to the Tropopause?

A

-2K / 1000’

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19
Q

What is the temperature Gradient at Lower Stratosphere?

A

Isotherm

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20
Q

What is the temperature Gradient at Upper Stratosphere?

A

+0.3K / 1000’

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21
Q

What is the structure of the Atmosphere Beyond ISA?

A 
Troposphere
Stratosphere 
Mesosphere 
Ionosphere
Exosphere
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22
Q

What may occur at the Ionosphere?

A

Radio blackouts and skip

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23
Q

What is the height of average Tropopause at the poles and equator?

A

Poles - 6-8km

Equator - 16-18km

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24
Q

Composition of ‘Real’ Atmosphere includes what?

A

Additional 4% water

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25
List problems due to Fog in Aviation
``` Airport reduced capacity Airport closure Go around Diversions Delays due to holding Taxi orientation issues. ```
26
What equipment and methods are used to measure fog?
Transmissometer (RVR) | Human Observation
27
What requirements do AC and crew use to deal with fog?
AC equipment AC technical status Crew licence.
28
State the conditions required for Radiation Fog
Clear sky Only over continent Light wind <10kt High humidity
29
What is the average thickness of Radiation Fog
<2m MIFG or BCFG | Max 100m - 200m
30
What time of day and season is Radiation Fog more prominent?
Build up after SS Most dense after SR Long lasting during winter months.
31
How is Radiation Fog dissipated?
Sun radiation | Following a wx change.
32
State the conditions required for Advection Fog
Moist and warm air Cold surface Wind / air stream.
33
What is the average thickness of Advection Fog?
500m - max 1000m | Widespread.
34
Describe Advection Fog and the seasons
Spring - Fog formed over sea due to warm continent and cold sea Autumn - Fog formed over continent due to warm sea and cold continent.
35
How is Advection fog dissipated?
Change of wx situation | Change of wind direction.
36
List conditions for Mixing Fog
Moist and warm air mixing with moist and cold air.
37
What is the thickness of Mixing Fog?
100km + wide along wx fronts
38
Mixing Fog is more prominent during which season?
Winter
39
How is Mixing fog dissipated?
Change of wx situation.
40
What factors can influence Visibility?
Visual object Observer Time of day Position of the sun
41
What is the importance of Visibility for VFR Pilots?
Flight planning and flight operation Vis at departure and destination airport Vis en-route.
42
What is the importance of Visibility for IFR pilots?
Fuel planning and flight operation Departure and destination minimas Alternate minima
43
What is the importance of Visibility for Controllers?
Operational category of the airport | Airport capacity.
44
Name the different Types of Visibility
``` Flight Ground in sight Slant RVR Vertical Ground. ```
45
Ground Visibility Decode 4000 9999 1300 0800SE
4000m >= 10km Prevailing vis 1300m, lowest vis 800m to the SE.
46
Vertical Visibility Decode VV003 VV/// VV000
Sky obscured, Vert Vis 300' Sky obscured, Vert Vis not available Sky obscured, Vert Vis <100'.
47
``` RVR Decode R1000 RP2000 R26L/0900D R07R/0800V1400U ```
RVR 1000m RVR >2000m RVR Rwy 26L 900m decreasing RVR Rwy 07R 800m variation 1400m upward tendency.
48
Decode FU
Smoke
49
Decode DU
Widespread dust
50
Decode SA
Sand
51
Decode VA
Volcanic ash
52
Decode HZ
Haze
53
Decode BR
Mist
54
Decode RA
Rain
55
Decode DZ
Drizzle
56
Decode SN
Snow
57
Decode FG
Fog
58
Decode MIFG
Shallow fog
59
Decode BLSN
Blowing snow
60
Decode DRSN
Drifting snow
61
How is wind measured?
Wind sock Wind vane Anemometer Height - 10m above GRD.
62
What is Mesoscale Wind System Force?
Gradient force due to pressure difference.
63
Describe the Mesoscale Pressure Gradient Force
From H to L pressure The closer the isobars, the greater the G The stronger the wind Wind equalises pressure very rapidly.
64
Describe Land / Sea Breeze
Sea breeze: Wind moving from cold water surface to warm continent. Present during day with calm fine wx. Land breeze: wind moving from cold land to warmer sea. at night
65
List Land / Sea Breeze Hazards
Sea Breeze - Wind shear, strong surface wind, possibly Advection Fog Land Breeze - Less intense than sea breeze.
66
Describe Mountain Down Slope / Valley Up Slope
Circulation of wind down up and through a valley. | Evident during sunny calm days.
67
List Mountain Down Slope / Valley Up Slope Flight Hazards
Mountain Down Slope - Fog or stratus | Valley Up Slope - Turbulence, wind shear, strong CWC.
68
List Foehn Wind Flight Hazards
Upwind Side - Low ceiling, poor vis, incessant rain, embd CB, ICE, TURB, GR Downwind Side - 30 - 50kt winds, rotor clouds - heavy TURB, mountain waves - heavy TURB.
69
What are the Physical States of Water
Solid Liquid Gas / Vapour
70
Definition of Dewpoint
The temperature (to which air has to be cooled down) at which condensation occurs.
71
List the Changing States of Water
``` Liquid to Solid - Freeze Solid to Liquid - Melt Liquid to Gas - Evaporate Gas to Liquid - Condense Solid to Gas - Sublimate Gas to Solid - Resublimate. ```
72
What are the hazards from Water to Aviation?
``` Fog Cloud Hail Freezing rain Snow Aquaplaning. ```
73
How is Atmospheric Humidity measured?
Hair hygrometer Psychrometer Dew Point mirror.
74
Definition of Spread
The difference between temperature and dew point.
75
``` If moisture in the air and temperature is constant what happens to Dew Point Spread Relative Humidity Probability of Fog ```
Increase Decrease Increase Increase.
76
How is Atmospheric Pressure measured?
Mercury Barometer | Aneroid Barometer.
77
What does Barometric Lapse Rate depend upon?
Altitude Temperature Humidity.
78
What are the Barometric Lapse Rates?
Up to 18,000' - 30' / 1hPa 18,000' - 36,000' - 60' / 1hPa 36,000' and above - 120' / 1hPa.
79
How is Atmospheric Temperature measured?
Mercury Thermometer Bimetallic Thermometer Resistance Thermometer.
80
When is coldest time of day?
30 min after SR
81
When is the hottest time of day?
2 hrs after noon.
82
Coldest months of the Year | Northern Hemisphere
Dec - Jan
83
Warmest months of the Year | Northern Hemisphere
Jun - Aug.
84
What is Inversion?
Layer of atmosphere where temp increases with height.
85
List influences of Air Density on Aviation
``` Performance Thrust Lift Runway length required Climb rate Drag. ```
86
What is the relationship between Air Density, Pressure, Humidity and Temperature
Air Density rises with increasing pressure and decreasing temperature Air Density decreases with decreasing pressure and increasing temperature Air Density decreases with increasing humidity.
87
What is the Human Critical threshold?
20,000' - 40,000'
88
List reasons for wrong Altimeter Indications
``` Mechanical - friction, calibration Dynamic - turbulent air, motion of AC Wrong subscale setting Air humidity Air temperature Air pressure. ```
89
Altitude Error due to Air Temperature
Hot to cold you'll never get old!
90
Altitude Error due to Air Pressure
High to low look out below!
91
What is the Dry Adiabatic Lapse Rate?
Ascending; -3K/1000' | Descending; +3K/1000'
92
What sort or air would a Dry Adiabatic Process occur?
Unsaturated
93
What is the Wet Adiabatic Lapse Rate?
Ascending; -2K/1000' | Descending; +2K/1000'
94
Within what sort of air would a Wet Adiabatic Process occur?
Saturated
95
When would a Dry Adiabatic Process turn into a Wet Adiabatic Process?
At the DP
96
What is a Stable Atmosphere?
An atmosphere where small incidental movements are suppressed and the vertical exchange in the atmosphere is low
97
Give examples of a Stable Atmosphere
Inversion | Isothermal Layer
98
What is an Unstable Atmosphere?
An atmosphere where small vertical disturbances result in vehement vertical motions. Strong irregular up and down drafts and turbulence.
99
Give examples of an Unstable Atmosphere
Thunderstorms, Tornadoes, CU Cloud
100
What type of cloud forms as a result of Thermal Convection?
Cumuliform
101
What type of cloud forms as a result of Forced Lifting?
Stratiform
102
What situations could cause Forced Lifting?
Mountain Ridge Front - Line Converging Surface Winds
103
Name the Characteristics of Cumuliform Clouds
``` Origin - Thermal Convection Stability - Unstable Vertical Speed - ~100-1000'/min and more Particle Size - Small Horizontal Extension - Small Precipitation - Shower Icing Type - Clear Turbulence - Moderate to Severe ```
104
What are the Characteristics of Stratiform Clouds?
``` Origin - Forced Lifting Stability - Stable Vertical Speed - ~1-10'/min Particle Size - Large Horizontal Extension - Widespread Precipitation - Continuous Icing Type - Rime Turbulence - None ```
105
Which Cloud Particles are most dangerous to Aviation?
Supercooled Droplets
106
State the Characteristics of NS
``` Nimbostratus Dark grey with precipitation Turb - Nil Icing - Rime Precipitation - Continuous DZ ```
107
State the Characteristics of CI
``` Cirrus Delicate - Hooks and feathers Turb - Nil Icing - Nil Precipitation - Nil ```
108
State the Characteristics of CS
``` Cirrostratus Thin white layers - Halo Turb - Nil Icing - Nil Precipitation - Nil ```
109
State the Characteristics of CC
``` Cirrocumulus Seperate flakes / balls Turb - Rapid Frequency Icing - Nil Precipitation - Nil ```
110
State the Characteristics of AS
``` Altostratus Layered uniform grey Turb - Nil Icing - Rime Precipitation - Nil ```
111
State the Characteristics of AC
``` Altocumulus Seperate white flakes, vertical extent Turb - Yes Icing - Clear Precipitation - Nil ```
112
State the Characteristics of ST
``` Stratus Uniform grey, low base Turb - Nil Icing - Rime Precipitation - DZ ```
113
State the Characteristics of SC
``` Stratocumulus Layered vertical structure, inversion above Turb - Yes Icing - Mixed Precipitation - Nil ```
114
State the Characteristics of CU
``` Cumulous Isolated vertical extension Turb - Yes Icing - Clear Precipitation - SH ```
115
State the Characteristics of CB
``` Cumulonimbus Great vertical development Turb - SEV Icing - Clear Precipitation - +SH ```
116
Up to what level do low clouds form?
~8000'
117
Up to what altitude do Alto Clouds form?
~20,000'
118
What are High level clouds called?
Cirro
119
Low clouds are made of what type of particle?
Water particles
120
What type of clouds are made up of water and ice particles?
Alto
121
Are Cirro clouds made of water or ice particles?
Ice
122
What equipment measures cloud amount and height?
Ceilometer
123
How can cloud amount be measured?
OKTAs
124
Describe the OKTA scale
``` 1 - 2 FEW 3 - 4 SCT 5 - 7 BKN 8 OVC 9 SKYOBS (VV) ```
125
What does CAVOK mean?
Cloud and Visbility OK Vis 10km or more (9999) No cloud below 5000' - No CB or TCU No significant WX
126
What would NSC indicate?
Nil Significant Cloud No cloud below 5000' - No CB or TCU or... Sky Clear
127
Define Ceiling
Height of the base of the lowest layer covering more than half the sky below 20,000'.
128
What do ISOL, LYR and EMBD mean?
Isolated Layered Embedded
129
What Categories of Precipitation are there?
Falling Deposed Stored
130
What is Falling Precipitation?
Precipitation resulting from clouds formed by the steam of the atmosphere
131
What is Deposed Precipitation?
Precipitation resulting from steam of the atmosphere which forms directly on the ground
132
What is Stored Precipitation?
Precipitation that remains on the ground
133
How is precipitation measured?
Rain gauge | 1m AGL
134
What is the Significance of Precipitation on Aviation?
``` Reduced flight vis Engine performance Flight performance Impaired aerodynamics Increased braking distance Frozen windshield Structural damage ```
135
How is the Intensity of precipitation annotated?
+ Heavy - Light Moderate
136
Decode FZDZ
Freezing drizzle
137
Decode SG
Snow grains
138
Decode FZRA
Freezing rain
139
Decode GS
Small hail
140
Decode PL
Ice pellets
141
How can icing be prevented in aviation?
Circumnavigation | De-icing equipment
142
What types of de-icing equipment are available in aviation?
Electric Thermal Pneumatic
143
List effects of icing on flight controls?
``` More weight Less lift Less thrust More drag Higher stall speed Blocked controls Antenna damage Air frame damage Frozen windshield ```
144
How can the light icing impact navigation?
Remain on course and altitude | Anti ice measures used temporarily
145
How can moderate icing impact navigation?
Change in course/altitude may be required | Anti ice measures used all the time
146
How can severe icing impact navigation?
Immediate change of course/altitude required | Anti ice measures are insufficient
147
How is icing formed on AC?
Transportation of warm water droplets inot cold areas
148
At what temperature are AC most vulnerable to icing?
0 - -6°
149
What weather conditions could lead to icing?
FZRA Cloud above freezing line or freezing line within cloud Warm fronts - supercooled area Cooling due to radiation
150
Describe the formation, appearance and characteristics of Rime Ice
Formation - Small supercooled droplets freezing instantly and maintaining shape Appearance - Milky and rough Characteristics - fragile and fairly easy to remove
151
What flight hazards are associated with Rime Ice?
More drag | Loss of lift
152
Describe the formation, appearance and characteristics of Clear Ice
Formation - Large supercooled droplets flowing back and freezing Appearance -Adapt to profile, smooth and clear Characteristics - Solid and hard to remove
153
What flight hazards are associated with Clear Ice?
Increase weight Rudder/flaps/slats may block More drag Less lift
154
What flight hazards are associated with Mixed Ice?
Combination of clear and rime ice
155
Describe the formation, appearance and characteristics of Mixed Ice
Formation - Small and large supercooled droplets Appearance - Mixture of clear and rime ice Characteristics - Mixture of clear and rime ice
156
Within what type of cloud would rime ice form?
ST, NS, AS
157
Within what type of cloud would clear ice form?
CU, AC, CB
158
Within what type of cloud would mixed ice form?
SC NS windward side
159
What factors could determine the intensity of icing on an AC?
``` Liquid water content - cloud type and freezing level AC type - aerofoil shape TAS - slower AC more at risk Duration of passage through area FL - warmer air = more water content ```
160
What are the characteristics of an inversion?
Stable atmosphere - no vertical air movement, no thermal convection, no cumuliform cloud types
161
What time of year and in what conditions are inversions most common?
Autumn and winter | Smog conditions
162
How does a surface inversion develop and what hazards does it pose to AC in flight
Develops like radiation fog | Reduces slant vis below due to HZ, BR, FG, wind shear
163
How does the duration of a surface inversion differ with the time of year?
Autumn and winter - long duration | Summer - short duration
164
Name the 3 types of Inversion
Surface Warm front Subsidence
165
What is a Warm Front Inversion?
Inversion formed as a result of warm air 'climbing ' up the back of cold air
166
State the properties of a Subsidence Inversion during summer months
Good vis above due to dry air | Cumuliform clouds form below
167
State the properties of a Subsidence Inversion during winter months
Good vis above due to dry air | ST with DZ, FG below
168
What are the flight hazards associated with Inversions?
Windshear Icing Wake Turbulence Poor ROC - Air density drop
169
When is an Inversion most dangerous to AC?
When close to the surface | Strong inversions with temperature rise of more than or equal to 10K below 650'
170
What is the PFJ?
Polar Front Jetstream
171
Where is the PFJ?
60° latitude | Upper tropopause
172
State characteristics and features of the PFJ
``` Very fast moving band of airflow Flows west to east Boundary between warm and cold air CAT (strong wind shear at the edges of a Jetstream) Several 1000km long High up in the upper tropopause ```
173
What effect does the time of year have on the PFJ and how does it affect weather in the UK?
Winter - PFJ drops below the UK allowing cold air to move further south over the UK Summer - PFL moves above the UK pushing cold air north and enabling warm air to cover UK
174
What affect does the Jetstream have on aviation?
Flight with PFJ - Reduction in flight time and more fuel efficiency Flight against PFJ - Longer flight time, more fuel required
175
What are the 2 main types of airmass?
Maritime - warm air with high humidity | Continental - cold dry air
176
What is a Front?
Boundaries or transition zones between 2 different air masses.
177
What hazards could Fronts pose to aviation?
``` Rain Low cloud base TS Icing Turbulence Change is wind direction ```
178
What are the characteristics of a Warm Front?
``` Cloud - CI, CS, AS, NS Speed - 20kts WX - Continuous RA, SN, FZRA, PL Wind movement - S-W Pressure - Decreases Temp - Increases Cloud base/Ceiling - Decreases to GND Vis - Decreases, possible mixing FG ```
179
What flight hazards are there with a warm front?
Light to moderate icing | Decrease to no VMC
180
What type of cloud could be included in a warm front?
EMBD CB
181
Name the 3 types of Cold Front
Passive Active Squall
182
What are the characteristics of a Passive Cold Front?
``` Cloud - NS (EMBD CB), AS, CS, CI, CU Speed - 30kts WX - Continuous SHRA, SHSN, TS Wind movement - Gusty W-N Pressure - Increases Temp - Decreases Cloud base/Ceiling - Low, rapid decrease Vis - Poor during RA ```
183
What flight hazards are there with a Passive Cold Front?
Icing Gusty winds EMBD CB TS
184
What flight hazards are there with an Active Cold Front?
``` Heavy Turbulence Gusts up to 50kts Severe Icing Windshear CB TS ```
185
What are the characteristics of an Active Cold Front?
``` Cloud - CU, CB, TCU Speed - Up to 50kts WX - +SHRA, +SHSN, +TS, GR, GS Wind movement - Strong gusty W-N Pressure - Rapid increase Temp - Notable decrease Cloud base/Ceiling - Rapid decrease Vis - Bad during RA ```
186
What does SQL mean?
Squall
187
When would you expect to see a Squall?
Moving ahead of an Active Cold Front.
188
What happens to the wind direction following a SQL?
During the the SQL, the wind moves 2x 180°, resulting in same wind direction as before the SQL
189
What happens to the temperature following a SQL?
During the SQL, temp will decrease due to showers and then become hot following the SQL.
190
What happens to the visibility during and after a SQL?
The vis will drop due to showers and continue to be bad following the SQL.
191
Name the most important type of a geostrophic wind
Jetstream
192
What is a CAT area?
Clear air turbulence
193
Name atmospheric situations where turbulence arises
- Turbulence in surface friction layer - thermal convection - orographically induced turbulence - clear air turbulence - wake turbulence
194
Why is turbulence hazardous ?
Can cause a sudden loss or gain in height/speed Notable direction changes Metal fatigue Resonance vibrations
195
What are Dynamic Lows and what frontal systems do they contain?
CF and WF systems formed due to the PFJ along a break of the tropopause
196
List the characteristics of the Rear Side of a Dynamic Low
``` Temp - Decreases Pressure - Rapidly increases Wind - N, NW and very gusty Clouds - CU, TCU, CB Ceiling - None, expect in SH Visibility - Very good Precipitation - SH ```
197
List the characteristics of the Front Side of a Dynamic Low
``` Temp - Increases Pressure - Rapidly decreases Wind - S, SW Clouds - CI, CS, AS, NS Ceiling - Low Visibility - Poor Precipitation - Incessant RA, SN ```
198
List the characteristics of the Warm Sector of a Dynamic Low
Temp - Constant Pressure - ~ constant, slow changes Wind - W Clouds - CI, AC, AS (Summer = CU, possible SQL, Winter = ST) Ceiling - Summer = None, Winter = Low Visibility - Summer = Moderate, Winter = Bad Precipitation - Winter = DZ
199
What is a WF Occlusion and what are the characteristics?
Where area of less cold air on the rear side, catches up with polar cold air on the front side. Season - Winter WX - WF WX, incessant RA
200
What is a CF Occlusion and what are the characteristics?
Where area of polar cold air on the rear side, catches up with less cold air on the front side. Season - Summer WX - CF WX, dominate SH
201
How are Thermal Lows created and what WX would you expect?
Created through strong surface heating. WX - RA, TS, +TS, +SHRA Not frontal For example, following a hurricane to the west, the air mass crosses the Atlantic.
202
What are the flight hazards of volcanic ash?
- possible false cargo-fire-warning - effect of sandblasting the cockpit window and surface of AC - VA damages the engines - total loss of thrust and vibrations - VA blocks the pitot tubes with result of false airspeed and altitude indication - antennas and deicing devices may be destroyed - VA pollutes the aircon system and the electrical-,fuel- and hydraulic systems
203
What are the flight hazards of thunderstorms?
- Turbulence - Strong up/down winds - windshear - hail - icing - lightning - gusts/squalls AVOID AVOID AVOID
204
What does the pilot do if he cannot avoid a TS?
- min time possible through the TS - be aware of heavy TURB and GR - avoid LVL with most critical icing - fly attitude, maintain trim - cont relight on - fasten seat belts/prepare cabin - r/t may be disturbed - check WX radar - inform ATC
205
MI
shallow
206
BC
patches
207
PR
partial
208
DR
low drifting
209
BL
blowing
210
UP
unknown precipitation
211
GR
hail
212
PO
dust/sand swirls
213
SQ
squalls
214
FC
funnel clouds
215
SS
sand storm
216
DS
dust storm
217
NCD
no clouds detected
218
NSW
nil significant weather
219
FRQ
frequent
220
ABV
Above
221
BLW
below
222
BTW/BTN
between
223
CLD
clouds
224
INTSF
intensifying
225
IMPR
improving
226
NC
not changing
227
OCNL
occasional
228
STNR
stationary
229
SFC
surface
230
WKN
weakening

ADI 03 (10 decks)

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