Transcript Week 9 Lecture

AVAT11001: Course Outline
1. Aircraft and Terminology
2. Radio Communications
3. Structure, Propulsion, Fuel Systems
4. Electrical, Hydraulic Systems and Instruments
5. Air Law
6. Aerodynamics: Basics
7. Aerodynamics: Performance
8. Human Factors
9. Meteorology
10. Loading
11. Take-off and Landing Performance
12. Navigation
Stuff to read
• Required Reading:
– BAK Chapter 7, pp. 229-246
– BAK Chapter 9, pp. 285-312
– VFG PLANNING, pp.53-82
The Atmosphere
• The atmosphere contains several layers
• Aviation is mostly concerned with the layer
closest to the surface of the earth, the
Troposphere
– This is where most “weather” occurs, as well as most
flying
• ISA, the International Standard Atmosphere
– This is a theoretical model of the atmosphere that is
primarily used to compare aircraft performance data
Local Weather
• The main weather concerns for pilots are:
– Wind: direction and magnitude
– Visibility: distance
– Clouds: coverage, type, and base level
• Also, any hazardous weather
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Thunderstorms
Fog
Precipitation
Turbulence
Icing conditions
Heat Effects
• Most weather is caused by the heating
and cooling of the air
– Warm air rises
– Cold air sinks
• Warm air is capable of holding more
moisture (water vapour) than cold air
• As warm air rises, it cools
– If the air contains moisture, clouds may form
when the air cools
Wind
• Wind is described by it speed (typically in knots) and its
direction
– The direction where is wind is coming from
– If you stand with the wind hitting you in the face, the direction
you are looking is the one that will be reported as the wind
direction
• Wind is caused by air flowing from high pressure areas
to low pressure areas
– Warm air rising creates low pressure areas
• Wind direction is also affected by the rotation of the earth
– This is called the Coriolis Effect
• In addition to navigation concerns (during cruise), wind
can have a large impact on operation on or near the
ground
Taxiing
• Wind can damage light aircraft when
taxiing
• Take precautions to ensure safety
– See Figures 7-2 though 7-4 page 231
– If the wind will raise your right wing, use the
ailerons to decrease lift on the right wing
– If the wind causes a nose down moment, use
the elevator to raise the nose
– If the wind causes a nose right yaw moment,
use the rudder to apply a nose left moment.
Take-Off and Climb
• See Figure 7-5 page 232
– Wind has a big impact on take-off distance
– Also affects climb angle
• Crosswind affects control
– Do not attempt to take-off or land if the
crosswind component is greater than that
allowed for your aircraft
– See Figure 7-6 page 232
Turns and the Circuit
• Wind changes your ground track during turns
– See Figure 7-11 page 235
• Be careful when flying the circuit pattern
– Avoid entering an accelerated stall trying to maintain
a particular ground track
– Pay attention to the ASI
– Avoid excessive back pressure on the control column
– Proficiency comes with practice
– If in doubt, err on the side of caution
• Level wings, increase power, and climb
Approach and Landing
• Headwind/Tailwind affects touchdown point
– See Figure 7-13 page 236
– Adjust rate of descent to land at desired spot
• Rule of thumb: descent in fpm = 5 x ground speed in knots
• Crosswind affect landing technique
– See Figure 7-16 page 237
– Crab technique
– Also wing-down technique can be used
• Landing distance required affected by wind
Windshear
• Windshear occurs at the boundary between to
air masses that are moving at different speeds
or in different directions
• This can be a hazard at altitude, because it can
suddenly change the load factor
• This can be a hazard near the ground, because
it can suddenly change altitude
– Many crashes have been caused by windshear
– Be careful flying into any area where strong
windshear has been reported
• Know how windshear affects climb and descent
– Overshoot/Undershoot caused by windshear
– See Figure 7-18 page 238 and Figure 7-20 page 239
Turbulence
• Turbulence is the name for wind that does not
flow smoothly
– Most air contains some amount of turbulence
• Know the 3 classifications of turbulence so that
you can communicate effectively (page 295)
• When encountering Moderate or Severe
turbulence, fly at the turbulence penetration
speed, VB
– Designed to be fast enough to avoid most gust
induced stalls
– Designed to be slow enough to reduce gust induced
load factors
Wake Turbulence
• Wake turbulence is caused by wingtip vortices
– See Figure 7-24 and Figure 7-27 page 241
• Avoid flying in the wake of other aircraft
– Especially large heavy jets
• Take-off techniques
– See Figure 7-29 page 242 and Figure 7-30 page 243
• Landing techniques
– See Figures 7-32 through 7-35 page 244
• If in doubt, wait
– Vortex strength decreases with time
Clouds
• Clouds are formed when moist air cools
below its dew point and water vapour
condenses
• Clouds are very useful to pilots
• They are a way to “see” the air
– Towering clouds show unstable air
– Thin layered clouds show stable air
• Know the abbreviations used for clouds
and what they look like
Forecasts and Reports
• Weather forecasts and reports are extremely important
to aviators
• Planning a safe flight requires knowledge of the weather
all along a desired route
• Know the different types of forecasts and reports and
what they tell you
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ARFOR
TAF
METAR/SPECI
TTF
• These reports are dealt with in greater detail in
AVAT12002
ATIS
• The automatic terminal information service
(ATIS) provides a report of the weather
conditions at a particular aerodrome
• Take-off and landing are the most dangerous
parts of flight
• Having the latest weather information can
greatly assist pilots in performing these tasks
safely
– Listen to ATIS prior to taxiing
– Listen to ATIS prior to making your inbound call
For next week…
• Required Reading: BAK Chapter 10, pp.
313-332