Download Review Meteorology and FARs

Review Meteorology and FARs
Meteorology/FAR and Review
• www.sal.ksu.edu/faculty/kingb
Weather Factors
• Atmospheric circulation
– Weather changes are caused by uneven heating
– Every process of weather is the result of or is
accompanied by a heat exchange
– The sun is directly over the Tropic of Cancer
on June 21
Weather Factors
• Highs are usually associated with
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Good visibility
Light winds
Few clouds
Good weather
Characterized by descending air
Weather Factors
– Lows are usually associated with
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precipitation
cloudiness
poor visibility
bad weather
turbulence
Wind
characterized by rising air
Example of lows are hurricanes and tornadoes
Weather Factors
• In the northern hemisphere
– Air flows counterclockwise around a low
(cyclonic)
– Air flows clockwise around a high
(anticyclonic)
– If one were to fly directly to the center of a low,
the winds would come from the left and get
stronger as one got closer
Weather Factors
• Relative Humidity
– Measure of how much moisture is present for a
a parcel of air at a temperature.
– If a parcel of air has a RH of 100%, it is
saturated. The temperature that it is at is called
the dewpoint. If this parcel were cooled more,
water vapor would clouds, fog, dew or frost
Thunderstorms
• Conditions
– Unstable air
– Lifting action
– High moisture content
• Stages
– Cumulus stage
– Dissipating stage
Mature stage
Hazards
• Embedded thunderstorms may be obscured
by cloud layers
• Wind shear can be found on all sides as well
as directly under it
• Greatest intensity during mature stage,
which is signaled by precipitation at the
surface
Frontal Turbulence
• Occurs in the narrow zone just ahead of a
fast-moving cold front
Wingtip Vortices
• Tend to sink below the flight path of the
generating aircraft
• Most hazardous during light, quartering
tailwinds
• Land beyond where a large aircraft has
touched down
Clear Air Turbulence
• Turbulence above 15,000 feet AGL not
associated with cumuliform cloudiness is
reported as CAT
• CAT is common in a upper trough on the
polar side of the jet stream
Mountain Wave Turbulence
• Greatest turbulence occurs approaching the
lee side of a mountain range in strong
headwinds
• Standing lenticular and rotor clouds indicate
the possibility of strong turbulence
Microbursts
• Intense, localized downdrafts seldom lasting
longer than 15 minutes
• Downdrafts can be as strong as 6,000 feet per
minute
• Performance changes drastically as an aircraft
flies through a microburst
Fog
• Radiation Fog - ground fog - forms over
fairly flat land on clear, calm nights
• Advection fog- forms near coastal areas
when moist air moves over colder ground or
water
Fog
• Upslope fog forms when moist stable air is
forced up a sloping land mass
• Steam fog occurs as cool air moves over warmer
water
• Precipitation-induced fog forms when warm
rain falls through a layer of cooler air near the
surface
Icing
• Freezing rain is most likely to have the
highest rate of accumulation
• Ice, snow or frost having the thickness and
roughness of sandpaper and reduce lift by
30% and increase drag by 40%
METAR
• Aviation routine weather reports
• METAR are routinely taken every hour at
50 past the hour. They are usually entered
into the computer on the hour
• SPECI are special aviation weather report
Sky Condition
• Ceiling is defined as the height of the
lowest layer of clouds or obscuring
phenomena that is reported as broken or
overcast
• If tops are know, your can find the thickness
of clouds by adding the airport elevation to
the height to the base of the clouds and
subtract from the height of the cloud tops
Remarks Codes
• A02 - automated station with precipitation
discriminator
• RAE42SNB42 - rain ended and snow began
at 42 past the hour
• PRESFR - Pressure falling rapidly
• SLP - Sea level pressure 1004.5 millibars
• T00081016 - Temperature .8o C and
dewpoint is -1.6o C
TAF
• Terminal Aerodrome Forecast - valid for a 24
hour period and scheduled four times a day
• Primary source of destination weather
• AMD means and amended forecast
• COR means a corrected forecast
• RTD indicates a delayed forecast
Contractions
• VRB - wind direction is variable
• 00000KT - calm wind
• P6SM - prevailing visibility expected to be
greater than 6 statue miles
• SKC - sky clear
• PROB40 2102 +TSRA - 40% probability of
thunderstorms with heavy rain between
2100Z and 0200 Z
Area Forecast FA
• VFR Clouds and weather section
summarizes sky condition, cloud heights,
visibility, obstructions to vision,
precipitation, and sustained surface winds
of 20 knots or greater
• When winds are to be 20 knots or greater
the categorical outlook includes the
contraction WND
Wind and Temperature Aloft
• Usually given for nine level between 3,000
and 39,000 feet
• Winds are given in true direction and speed in
knots
• Winds not forecast within 1,500 feet of station
elevation
• Temperature not forecast for the 3,000-foot
level or with 2,500 feet of the station elevation
Wind and Temperature Aloft
• Uses a four digit code for wind speed and
direction, the first two digits are the wind
direction in hundreds of degrees
• The second two digits indicate wind speed
• A two digit temperature code in degrees
Celsius follows the wind speed and direction
code
• All temperature above 24,000 feet are negative
Surface Analysis Chart
• Surface Analysis chart is a good source for
general information over a large area. Shows
position of fronts, temperature, dewpoint,
wind at valid time of the chart
• When solid lines, called isobars, are close
together the pressure gradient is greater and
the winds are stronger
• A dashed line indicates a weak pressure
gradient
Weather Depiction Chart
• Information on the chart is derived from the
METAR reports
• Provides an overview of favorable and
adverse weather
• Prepared every three hours
• A bracket symbol ] to the right of a station
circle means it is an automated location
RADAR Summary Chart
• Only chart which shows lines and cell of
thunderstorms
• You can determine the tops and bases of the
echoes, the intensity of the precipitation and
direction of movement
• Most effective when used in combination
with other charts, reports, and forecasts
Graphic Forecasts
• Low-level Significant Weather Prognostic
Chart is valid up to 400 millibars of
pressure or about 24,000 feet
• Issued four time a day with a valid time
printed on the lower margin of each panel
• Shows areas of IFR, MVFR, VFR and
moderate or greater turbulence
Graphic Forecasts
• Severe Weather Outlook Chart is used for
advance planning and provides 48-hour
outlook for general and severe thunderstorm
activity
• Crosshatched areas generally indicate
severe weather and are labeled SVR
Types of Briefings
• Standard is the most complete briefing and
assumes no familiarity with the weather picture
• Abbreviated is used to update weather
information when you need only one or two
specific items
• Outlook is used if you departure is six or more
hours away. You should update with a standard
or abbreviated briefing closer to flight time
In-Flight Weather Sources
• Airmets - WA - Airmans meteorological
information are forecasts for a maximum of
a six hour period
• Sierra for IFR conditions
• Tango for turbulence
• Zulu for icing and freezing levels
SIGMETs
• Significant meteorological information WS –
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Severe Icing
Severe and extreme turbulence
Volcanic eruptions
Duststorms, sandstorms or volcanic ash
lowering visibility to less than three miles
Convective SIGMETs
• Imply severe or greater turbulence, severe
icing and low level wind shear
• Contain either an observation and a forecast
or just a forecast for tornadoes, significant
thunderstorm activity or hail 3/4 inch or
greater in diameter
Enroute Flight Advisory Service
• Flight Watch is available daily from 6 AM
to 10 PM when flying between 5,000 AGL
and 17,500 MSL any where in the US
• Contact on 122.0 with your aircraft ID,
ARTCC facility identification and name of
the nearest VOR
FAR 1
Definitions & Abbreviations
• Flight Visibility - average horizontal
forward distance from the cockpit.
• Ground Visibility - prevailing horizontal
visibility near surface as reported by US
NWS or an accredited observer.
• IFR conditions - not VFR below 1000 and 3
FAR 61
• 61.57 (C) - To act PIC under IFR, within
preceding 6 calendar months:
– Logged 6 approaches
– Holding procedures
– Intercepting and tracking courses through use
of nav systems
– Note: A Sim or FTD may be used.
Part 91
• 91.3 - PIC is PIC
• 91.21 - use of electronic devices that may
cause interference with nav systems is
prohibited.(cell phones, stepping motors
etc.)
• 91.103 - Latest info required, alternatives
available, known traffic delays.
Part 91
• 91.167- Enough fuel to fly to first airport,
then if an alternate is required, fly to
alternate airport, then fly for 45 min after at
normal cruising speed. An alternate is not
required if 1 hr of ETA, 2000’ ceiling, 3
miles visibility.
Part 91
• 91.169 - To be an alternate, unless
denoted by A in triangle on NOS charts
– Precision approach - 2 mi., 600’
– Non precision approach - 2 mi., 800’
– No approach - allow descent from MEA
to approach and landing under VFR
Part 91
• 91.185 - Comm Failure
– If IFR
• Route
– Last assigned
– Radar vectored, direct to fix, route or
airway specified in vector clearance.
– EFC
– Filed
Part 91
• 91.185 - Comm Failure
– If IFR
• Altitude - Highest of
– Last assigned
– MEA
– EFC
• Time
– Commence approach as close as possible
to EFC or filed.
Part 91
• 91.205 Instrument and Equipment
Readiness
– For IFR flight, navigation equipment must be
appropriate to ground facilities
– Above 24,000, DME required if using VOR
navigational equipment
– Need attitude indicator, heading indicator and
turn coordinator for IFR
Part 91
• 91.211 Supplemental Oxygen
– Above 15,000, each passenger must be
provided supplemental oxygen
– Above 14,000, required crew must use
– Between 12,500 and 14,000, oxygen must be
provided for time in excess of 30 minutes
Part 91
• 91.215 ATC Transponder and Altitude
Reporting Equipment and use
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Must use Mode C
Within Class B
Within 30 NM of primary Class B airport
Within and above Class C
Above 10,000 ft MSL except below 2,500 AGL
and in Class A airspace
Part 91
• 91.411 Altimeter System and Altitude
Reporting Equipment Test and Inspections
– Each static pressure system and altimeter instrument
must be tested by the end of the 24th month
NTSB 830
• Accidents, incidents, overdue AC, and
preservation of wreckage