Stage 2 Check List Flashcards
(34 cards)
Standard temperature and pressure
Standard temperature is 15°C
Standard pressure is 29.92
Or one inch per 1000 feet
Lapse rate/ pressure change
Rate at which temperature decreases with altitude
Standard laps rate is 2°C per 1000 feet
Dry adiabatic lapse rate is 3 per 1000 feet
One inch per 1000 feet
High and low pressure system
High pressure surround on all sides by lower pressure
Ridge elongated are of high pressure
Air flows clockwise down and out
Low pressure system
Is a lower pressure (does not matter if it is a high pressure system as long as it is lower then the other front)
Low pressure surrounded on all sides by higher pressure
Trough elongated area of low pressure
Air flows counterclockwise up and in
Temperature inversion
Temperature increases with altitude Smooth stable layer of air Restricted visibility below inversion Turbulence above inversion 2 types
Surface based temperature inversion
Cool clear calm nights
Ground cools lowers temperature of air
Frontal temperature inversions
Cool air forced under warm air
Warm air spreads over cool air
3 things needed for clouds
1 condensation nuclei
2 moisture
3 small temperature dew point spread
Low clouds
SFC 6500 AGL
Composed of super cool water drops
Stratus, nimbostratus, stratocumulus
Rime ice
Middle clouds
6500 AGL 20,000 AGL
Composed of large super cool water drops
Altostratus altocumulus
Mix icing
High clouds
20k- 60k
Composed of ice particles
Cirrus cirrocumulus cirrostratus
No icing
Extensive vertical development
Any altitude Composed of all Very unstable and turbulent Cumulus cumulonimbus towering cumulus All types of ice and hail
First layer of cloud temp-dew point divided by 4.4 X 1000 = cloud height
Formation of fog (surap)
Steam Cold, dry moves over warm water Examples lakes in the morning Upslope Moist air is lifted by rising terrain Cools with altitude condenses Requires 15k wind Radiation At night ground cools cools air above it to dew point and condenses Clear calm humid nights Low lying fog ( in valley) Morning warm up "burn off" the fog Advection Warm moist air moves over cooler surface SFC cools air to Dewpoint and condenses Coastline under cloudy skies Requires winds to develop 15+ kts Examples the ocean Precipitation induced Rain evaporates and cooled to dew point Warm rain falls though cool air saturated it Creates dense fog
Stable and unstable air VCTIPP
Stable Visibility poor Clouds stratus Turbulence none Ice rime Precipitation steady Pressure high pressure Unstable Visibility good Clouds cumulus Turbulence more severe Ice clear ice Precipitation showery Pressure low pressure
Thunderstorms ( things needed for development)
Single greatest threat to aviation Requirements for development are high moisture content Unstable air Uplifting force
Life cycle of a thunderstorm
Cumulus stage
Average 15 minutes
Updrafts
Building of clouds
Mature stage Precipitation 15 to 30 minutes Updrafts and downdrafts Lightning Anvil top clouds
Dissipating stage Last about 15 minutes No more precipitation Downdrafts Storm goes away
Windshear
Sudden, drastic change in wind speed and or direction
May occur in the vertical or horizontal plane
Most dangerous at low levels
Often exists near the surface when there is a
Frontal system
Thunderstorm
Temperature inversion with strong upper level winds
To protect against wind shear many airports have LLWAS
low level windshear alert system
Provides warning for possible windshear conditions
Takes measurements from multiple locations around airport
Virga
Tiny rain drops that fall and evaporate before reaching the ground
Evaporation cools air
Cool air sinks faster creating down drafts
Heavy down drafts up to 6000 feet per min
Precursor to a microburst
Structural icing
Ice build up on air craft surface
Surface of aircrafts the at or below 0 C
OAT + 5 degrees C - aircraft may be colder due to reduced pressure of faster moving air lowering temperature at point of contact
METAR
Aviation routine reports Updated every hour between 45 mins past the hour and the hour Same format as ATIS report Type of report (METAR, speci) Station ICAO identifier (KCHD) Date and time of report (133250Z)( dayhrmin) Modifier (optional) (auto ,COR) Winds in true north (08020G38kts) Visibility (6sm) Weather codes (sh,ts,br) Sky conditions and clouds reported in AGL Few= 0-2/8 sky coverage Scattered SCT= 3/8-4/8 Broken BKN = 5/8-7/8 Overcast OVC= 8/8 sky coverage Ceiling is the lowest level listen as BKN or OVC temperature/ dewpoint Altimeter setting Remarks (rmk) Sea level pressure is SLP134= 1013.4 millibars Type of station A01 A02
PIRPEPS (UA/UUA)
PIREPS are real time weather reporting information
Anytime you encounter unforecasted weather you are encouraged to make a PIREP
File PIREP with Prescott radio 122.6 (different)
If icing is reported in a PIREP it is considered known icing condition
When filing a PIREP include the following
Mandatory items
Type of report (UA or UUA)
OV Location to NAVAID
TM Zulu time
FL flight level or altitude
TP aircraft type
Non mandatory (only if existence)
SK Sky cover
WX visibility and Weather
TA temperature
WV winds in magnetic north
TB turbulence
IC icing
RM remarks
TAF
Terminal aerodrome forecast
Issued four times per day valid for 24 hrs
Valid for the reporting airport and up to a five statute mile radius circle around that airport
Provides forecast information in a metar format
Key terms AMD-amended, TEMPO- Temporary, FM-From, BECMG-Becoming
FA
Area forecast
Issued three times a day
Valid for a total of 18 hours (12 hours forecast in a six hour categorical outlook)
Covers an area of several states
Six different FA regions in contiguous SFO, SLC, CHI, DFW, BOS, MIA, we use SLC.
Comprised of four sections
1 Communications and product helper: issue time, valid times, affected areas
2 precautionary statement, reminds to see AIRMET’s and Heights are MSL
3 synopsis, gives a brief summary of location and movement of fraud, pressure systems and circulation patterns (valid for 18 hours)
4 VFR clouds and Weather section: 12hr specific forecast
Breaks weather into smaller geographical areas
Describes clouds and weather affecting VFR operations
Categorical outlook - IFR, VFR, MVFR (valid for 6 hrs)
FD
Winds and temperatures Aloft Forecast
Winds reported from different altitudes in true north
Issued two times a day and up to 4 times a day
No temperatures for 3000 feet level or within 2500 feet of station elevation
No wind within 1500 feet of station elevation
9900 denotes when that are light and variable less than 5 knots
0000 denotes calm winds
Wind greater than 99 that are encoded by subtracting 50 from the direction and adding for 100 to the speed
Temperatures are always negative above 24,000 feet
WS (Sigments)
Issued for hazardous non-convective whether to all aircraft
Issued as needed valid for four hours unless hurricane related then valid for six hours
Includes following conditions
Severe icing, severe turbulence, clear air turbulence, dust storms in sandstorms lowering visibility to less than 3 miles, volcanic ash
WST (convective sigments)
Issued every hour 55 Min past the hour even if there is no convective weather
Issued for hazardous convective whether to all aircraft
Includes the following conditions
Tornadoes, line of thunderstorms squall lines, thunderstorms over a wide area, embedded thunderstorms, hail greater than or equal to 3/4 inch at the surface, winds gusts to 50 kn or greater
WA ( AIRMET)
Warn of weather conditions that are particularly hazardous to small aircraft but applies to all
Issued every six hours valid for six hours
