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Instrument Flying Handbook
Flight Instruments
Safety Systems

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Instrument Flying


Table of Contents

Chapter 1. Human Factors
Chapter 2. Aerodynamic Factors
Chapter 3. Flight Instruments
Chapter 4. Section I
Airplane Attitude Instrument
Using Analog Instrumentation
Chapter 4. Section II
Airplane Attitude Instrument
Using an Electronic Flight

Chapter 5. Section I
Airplane Basic
Flight Maneuvers
Using Analog Instrumentation
Chapter 5. Section II
Airplane Basic
Flight Maneuvers
Using an Electronic Flight

Chapter 6. Helicopter
Attitude Instrument Flying

Chapter 7. Navigation Systems
Chapter 8. The National
Airspace System

Chapter 9. The Air Traffic
Control System

Chapter 10. IFR Flight
Chapter 11. Emergency

Its primary application is to provide accurate absolute altitude
information to the pilot during approach and landing. In
advanced aircraft today, the radar altimeter also provides its
information to other onboard systems such as the autopilot
and flight directors while they are in the glide slope capture
mode below 200-300 feet above ground level (AGL).

A typical system consists of a receiver—transmitter (RT)
unit, antenna(s) for receiving and transmitting the signal,
and an indicator. [Figure 3-51] Category II and III precision
approach procedures require the use of a radar altimeter and
specify the exact minimum height above the terrain as a
decision height (DH) or radio altitude (RA).

Components of a Radar Altimeter
Figure 3-51 - Components of a Radar Altimeter

Traffic Advisory Systems
Traffic Information System

The Traffic information Service (TIS) is a ground-based
service providing information to the flight deck via data
link using the S-mode transponder and altitude encoder. TIS
improves the safety and efficiency of "see and avoid" flight
through an automatic display that informs the pilot of nearby
traffic. The display can show location, direction, altitude
and the climb/descent trend of other transponder-equipped
aircraft. TIS provides estimated position, altitude, altitude
trend, and ground track information for up to several aircraft
simultaneously within about 7 NM horizontally, 3,500 feet
above and 3,500 feet below the aircraft. [Figure 3-52] This
data can be displayed on a variety of MFDs. [Figure 3-53]

Figure 3-54 displays the pictorial concept of the traffic
information system. Noteworthy is the requirement to have
Mode S and that the ground air traffic station processes the
Mode S signal.

Traffic Alert Systems
Traffic alert systems receive transponder information from
nearby aircraft to help determine their relative position to the
equipped aircraft. They provide three-dimensional location
of other aircraft [Figures 3-55, 3-56, and 3-57/ and are cost
effective alternatives to TCAS equipage for smaller aircraft.

Coverage Provided by a Traffic J0formotion System.
Figure 3-52. Coverage Provided by a Traffic Information System.

Traffic Avoidance Systems
Traffic Alert and Collision Avoidance System (TCAS)

The TCAS is an airborne system developed by the FAA that
operates independently from the ground-based ATC system.
TCAS was designed to increase flight deck awareness of
proximate aircraft and to serve as a "last line of defense" for
the prevention of mid-air collisions.

There are two levels of TCAS systems. TCAS I was developed
to accommodate the general aviation (GA) community and
the regional airlines. This system issues traffic advisories
(TAs) to assist pilots in visual acquisition of intruder aircraft.
TCAS I provides approximate hearing and relative altitude
of aircraft with a selectable range. It provides the pilot
with traffic advisory (TA) alerting him or her to potentially
conflicting traffic. The pilot then visually acquires the traffic
and takes appropriate action for collision avoidance.

TCAS II is a more sophisticated system which provides the
same information of TCAS I. It also analyzes the projected
flight path of approaching aircraft and issues resolution
advisories (RAs) to the pilot to resolve potential mid-air
collisions. Additionally, if communicating with another
TCAS II equipped aircraft, the two systems coordinate the
resolution alerts provided to their respective flight crews.
[Figure 3-58]