Download The Functions of Airspeed Indicators

Flight Instrumentation
Warm-Up Questions
CPS Questions 1-2
Chapter 4, Lesson 4
Lesson Overview
 The
functions of airspeed indicators
 The functions of the altimeter
 The functions of a horizontal situation
indicator
 The functions of attitude indicators
Chapter 4, Lesson 4
Quick Write
Since the Miracle on the Hudson, Captain
Sullenberger has become a hero to many.
Why do you think that is?
(Note to teacher: Use “Pick a Student” button in CPS)
Chapter 4, Lesson 4
© Brendan McDermid/Reuters
The Functions of Airspeed
Indicators
An airspeed indicator is an
instrument in the cockpit that
displays an aircraft’s airspeed
 Determines airspeed by
measuring the difference
between dynamic pressure
and static pressure
 Gets its data from a system
called the pitot-static system

Chapter 4, Lesson 4
Reproduced from US Department of
Transportation/Federal Aviation Administration
The Functions of Airspeed
Indicators, cont.
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Pitot tube captures dynamic as
well as static pressure
Pitot tube’s pressure chamber
sends the total pressure to the
airspeed indicator
Static port sends static pressure
to the airspeed indicator
When the dynamic pressure
changes, airspeed indicator
shows either increase or
decrease
Chapter 4, Lesson 4
Reproduced from US Department of
Transportation/Federal Aviation Administration
Types of Airspeed
Indicated—Airspeed shown on the airspeed
indicator
 Calibrated—Indicated airspeed corrected for
installation error and instrument error
 Equivalent—Speed at sea level
 True—Calibrated airspeed corrected for
altitude and temperature
 Groundspeed—Airplane’s actual speed over
the ground

Chapter 4, Lesson 4
Airspeed Indicator Markings
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Airspeed indicator has color-coded
markings
White arc— Aircraft’s operating
range for approaches and landings
Green arc—Aircraft’s normal
operating range
Yellow arc—Range in which a pilot
should be cautious
Red line—Pilot should never
exceed this speed
Chapter 4, Lesson 4
Reproduced from US Department of
Transportation/Federal Aviation Administration
Activity 1: Calculating True
Airspeed
 Read
the information about corrections
to indicated airspeed on the airspeed
indicator
 Examine
the example on how to
calculate true airspeed and then solve
the problems
Chapter 4, Lesson 4
Activity 2: Airspeed Indicators
 Review
the textbook information on
airspeed indicator markings
 Answer
the questions about the
airspeed indicator in your own words
Chapter 4, Lesson 4
Learning Check Questions
CPS Questions 3-4
Chapter 4, Lesson 4
The Functions of the Altimeter
 The
altimeter is the only
navigation instrument
that can indicate altitude;
it is one of an aircraft’s
most important devices
 Common type of altimeter
is the pressure altimeter
Chapter 4, Lesson 4
"Reproduced from US Department
of Transportation/Federal Aviation
Administration"
Standard and Nonstandard
Pressure and Temperature

The altitude shown on the altimeter
face is correct only when certain
standards are met:
 Sea level barometric pressure of
29.92 inches of mercury
 Temperature of 59 degrees F
(15 degrees C)
 Standard rate of decrease in
pressure and temperature with
an increase in altitude
Chapter 4, Lesson 4
Reproduced from US Department of
Transportation/Federal Aviation
Administration
Pressure
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Since barometric pressure and
temperature generally don’t
remain constant; pilots must
adjust their altimeters
If flying from high-pressure
area to a low-pressure area
without adjusting the
altimeter, the aircraft’s actual
height would be lower than
the altimeter indicates
The reverse is also true
Chapter 4, Lesson 4
Courtesy of NASA
Temperature
When flying in temperatures that are colder than
standard, the actual altitude will be lower than the
altimeter indicates
 When the air is warmer than standard, the aircraft
will be higher than the altimeter says
 Pilot can correct for temperature with the help of a
computer

Chapter 4, Lesson 4
Reproduced from US Department of
Transportation/Federal Aviation Administration
Activity 3: Altimeters and
Temperature
 Determine
the air or ground temperature
or altitude
 Examine
the examples and solve the
problems
Chapter 4, Lesson 4
Learning Check Questions
CPS Questions 5-6
Chapter 4, Lesson 4
The Functions of a Horizontal
Situation Indicator
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HSI is a flight instrument that indicates an aircraft’s
position and direction in relation to the desired
route
Information includes: magnetic heading, course the
pilot has selected, deviation from the intended
course, runway’s magnetic course, deviation from
the intended descent, and red warning flags when
HSI isn’t working properly
Chapter 4, Lesson 4
Reproduced from US Department of Transportation/Federal
Aviation Administration
Activity 4: Functions of the
Horizontal Situation Indicator

Review the textbook information on the
functions of a horizontal situation indicator
(HSI)

Describe in your own words the functions
of some features on the HIS and what they
tell a pilot
Chapter 4, Lesson 4
The Functions of
Attitude Indicators
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Displays an aircraft’s attitude
Can alert the pilot to possible changes
in airspeed, altitude, and direction
Works according to gyroscopic rules;
features a fixed aircraft on its face and
a freely moving horizon bar
Miniature aircraft’s relationship to the
horizon bar is the same as the real
aircraft’s relationship to the real
horizon
Chapter 4, Lesson 4
Reproduced from US Department of
Transportation/Federal Aviation Administration
Attitude Indicator

An attitude indicator generally has limits as
to how much pitch and roll it can indicate
Chapter 4, Lesson 4
Reproduced from US Department of
Transportation/Federal Aviation Administration
Activity 5: Attitude Indicator
Readings

Review the textbook information on the
functions of attitude indicators

Answer the questions about the attitude
indicator and determine the readings
Chapter 4, Lesson 4
Learning Check Questions
CPS Questions 7-8
Chapter 4, Lesson 4
Activity 6 Flight Simulator:
Flight Instruments

Identify the different aircraft flight
instruments using Microsoft Flight Simulator
Chapter 4, Lesson 4
Summary
 The
functions of airspeed indicators
 The functions of the altimeter
 The functions of a horizontal situation
indicator
 The functions of attitude indicators
Chapter 4, Lesson 4
Review Questions
CPS Questions 9-10
Chapter 4, Lesson 4
Next….
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Done – flight instrumentation

Next – navigation technology
Chapter 4, Lesson 4
Courtesy of NASA/Tom Tschida