BendixKing KTA 910 User Manual
N
KTA870/
Pilot’s Guide
Multi-Hazard Awareness System
KMH880
B
Traffic Advisory System/
Rev. 3 006-18265-0000
The information contained in this manual is for reference use only. If
any information contained herein conflicts with similar information
contained in the Airplane Flight Manual Supplement, the information in
the Airplane Flight Manual Supplement shall take precedence.
WARNING
The enclosed technical data is eligible for export under License Designation
NLR and is to be used solely by the individual/organization to whom it is
addressed. Diversion contrary to U.S. law is prohibited.
COPYRIGHT NOTICE
Copyright © 2001, 2002, 2004, 2005 Honeywell International Inc.
All rights reserved.
Reproduction of this publication or any portion thereof by any means without
the express written permission of Honeywell International Inc. is prohibited. For
further information contact the Manager, Technical Publications; Honeywell;
One Technology Center; 23500 West 105th Street; Olathe, Kansas 66061.
Telephone: (913) 712-0400.
Revision History
Manual KTA870/KMH880 Pilot’s Guide
Revision 3, January 2005
Part Number 006-18265-0000
This revision clarifies the determination of when other aircraft are on the
ground, and clarifies the GA-EGPWS Self-Test process.
The following pages were changed or added:
Front Cover, Copyright, 14, 53, 54, Back Cover
R-1
Revision History
Manual KTA870/KMH880 Pilot’s Guide
Revision 2, January 2004
Part Number 006-18265-0000
This revision is to correct errors and to remove references to a specific
type of database card.
The following pages were changed or added:
Front Cover, Copyright, 37, 41, 46, 59, 60, Back Cover
R-1
Revision History
Manual KTA870/KMH880 Pilot’s Guide
Revision 1, March 2002
Part Number 006-18265-0000
This revision incorporates changes from the KGP 560.
R-2
Revision History
Manual KTA870/KMH880 Pilot’s Guide
Revision 0, March 2001
Part Number 006-18265-0000
This is the original version of this publication.
R-3
KTA 870/KMH 880 Pilot’s Guide
TAS System Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Traffic Displays: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
TAS Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
TAS Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
TAS: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Section I : TAS Theory of Operation and Symbology . . . . . . . . 5
TAS Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
TAS Sensitivity Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
TAS Surveillance Volumes . . . . . . . . . . . . . . . . . . . . . . . . . 8
(1) Range Tracking Volumes . . . . . . . . . . . . . . . . . . . . 8
(2) Altitude Tracking Volumes . . . . . . . . . . . . . . . . . . . 8
TAS Aural Inhibits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
TAS Traffic Display Symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Non-Threat Traffic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Proximity Intruder Traffic . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Traffic Advisory (TA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
No Bearing Traffic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Off Scale Traffic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
TAS Indications and Voice Announcements . . . . . . . . . . . . . . 12
TAS Traffic Advisory Annunciation (TA): . . . . . . . . . . . . . . 12
Section II : TAS Controls and Displays . . . . . . . . . . . . . . . . . . . 15
TAS Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
TAS Control & Display; KMD 550/850 . . . . . . . . . . . . . . . . 15
KMD 550/850 Traffic Page (TAS) Operational Controls. . . 16
TAS Control Panel; CP 66B . . . . . . . . . . . . . . . . . . . . . . . 17
Power Switch: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Range Knob: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Display Select Switch: . . . . . . . . . . . . . . . . . . . . . . . . . 18
Altitude Limit Switch: . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Weather Radar Indicators . . . . . . . . . . . . . . . . . . . . . . . . 19
RDS 81, 82, 84 & 86, RDR 2000, RDR 2100 and
Primus /Collins Color Indicators . . . . . . . . . . . . . . . . . 19
Weather Only Mode . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Weather with TAS Traffic Mode . . . . . . . . . . . . . . . . . 20
TAS Only Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Wx & TAS Message Formats . . . . . . . . . . . . . . . . . . . . . . 21
TAS Mode Annunciations: . . . . . . . . . . . . . . . . . . . . . 21
TAS Fault Annunciations: . . . . . . . . . . . . . . . . . . . . . 22
Weather Only and Weather w/TAS Mode . . . . . . . . 22
TAS ONLY mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Section III: TAS Operational Procedures . . . . . . . . . . . . . . . . . . 23
TAS Operating Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Before Takeoff . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Flight Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Table of Contents
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After Landing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Post Flight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Section IV: TAS System Considerations . . . . . . . . . . . . . . . . . . 27
Limitations And Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Appendix: TAS Self Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
TAS Self Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Failure Conditions: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Radio Altimeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Glossary of TAS Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Abbreviations and Definitions . . . . . . . . . . . . . . . . . . . . . . 32
EGPWS (Optional)
EGPWS Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
What is the GA-EGPWS? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Regulatory Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
GA-EGPWS Functions and Features . . . . . . . . . . . . . . . . . . . . . 39
Aircraft Position . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Aircraft Altitude . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Terrain, Obstacles & Runway Database . . . . . . . . . . . . . . . . . 41
Terrain Inhibit Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Terrain Awareness Display . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
“Look-Ahead” Alerting and Warning . . . . . . . . . . . . . . . . . . . . . 48
Runway Field Clearance Floor (RFCF) . . . . . . . . . . . . . . . . . . 49
Excessive Rate of Descent Alerting and Warning . . . . . . . . . . 50
Inadvertent Descent / Loss of Altitude After Take-Off . . . . . . . 51
GA-EGPWS Altitude Monitoring . . . . . . . . . . . . . . . . . . . . . . . . 52
Altitude Callout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
EGPWS NORMAL PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . 53
GA-EGPWS System Self-Test . . . . . . . . . . . . . . . . . . . . . . . . . 53
Recommended Procedures for EGPWS Warnings In Flight . . 55
“PULL UP” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Recommended Procedures for EGPWS Alerts In Flight . . . . . 55
ADDITIONAL EGPWS INFORMATION . . . . . . . . . . . . . . . . . . . . . 57
Audio Message Priority . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
GA-EGPWS Cockpit Lamps & Switches . . . . . . . . . . . . . . . . . 58
GA-EGPWS System Limitations . . . . . . . . . . . . . . . . . . . . . . . 58
GA-EGPWS Continued Airworthiness and Database
Update Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
GA-EGPWS Product Support . . . . . . . . . . . . . . . . . . . . . . . . . 60
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SYSTEM COMPONENTS
TRAFFIC DISPLAYS:
KMD 850
Compatible Radar Indicators via GC 362A
Compatible EFIS
TA/VSI
TAS CONTROLS:
KMD 850
CP 66B TCAS I Controller
Discretes
OPTIONAL EGPWS CONTROLS & DISPLAYS:
KMD 850
Compatible Radar Indicators
Discretes
AUDIO PANEL
Headphone/600 Ohm
TOP ANTENNA
Directional
KA 815
KTA 870/
KMH 880
TAS
PROCESSOR
TRAFFIC DISPLAY/CONTROL
Comprised of the following cards:
TAS System Components
Option 1
KMD 540
KAC 502 (EGPWS) and/or
KAC 504 (TAS)
CONFIGURATION MODULE
CM 805
OR
Option 2
No Control Unit
Discrete Control
TST
SBY
BOTTOM ANTENNA
Omni-Directional
(L-Band)
GPS ANTENNA
KA 92
PWR
AIRCRAFT SYSTEMS
OR
Directional
KA 815
• Barometric Altitude - Gilham, ARINC 429
• Heading - XYZ Synchro
• Suppression
• Discretes
• Outside Air Temperature
SYSTEM STATUS
• TAS VALID
• EGPWS INOP
A/B
FL
KTA 870/KMH 880 Block Diagram
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KTA 870/KMH 880 Pilot’s Guide
TAS Introduction
INTRODUCTION
TAS (an acronym formed from the phrase Traffic Advisory System) is an
airborne system used for detecting and tracking aircraft near your own
aircraft. TAS includes a TAS processor, antennas, a traffic display and a
means to control the system. The TAS processor and antennas detect
and track other aircraft by interrogating their transponders. Aircraft
detected, tracked, and displayed by TAS are referred to as Intruders.
TAS analyzes the transponder replies to determine range, bearing and
relative altitude, if the Intruder is reporting altitude. Should the TAS
processor determine that a possible collision hazard exists, it issues
visual and aural advisories to the crew. The visual advisory is shown by
symbols on the traffic display. Complementing the traffic display, TAS
provides appropriate synthesized voice announcements in the cockpit. A
complete list of traffic symbols and announcements is given in the
Theory of Operation and Symbology section of this Pilot’s Guide.
TAS is unable to detect any Intruding aircraft without an operating
transponder. TAS can detect and track aircraft with either an
ATCRBS (operating in Mode A or C) or Mode S transponders.
The traffic display shows the Intruding aircraft’s position. TAS identifies
the relative threat of each Intruder by using various symbols and colors.
The Intruder’s altitude, relative to your own aircraft’s altitude, is annunciated if the Intruder is reporting altitude. A trend arrow is used to indicate
if the Intruder is climbing or descending more than 500 feet per minute.
TAS traffic may be displayed on a weather radar indicator, on a dedicated TAS display, on a TAS compatible EFIS Display Unit or a TA/VSI
(combination traffic display and vertical speed instrument).
TAS modes and functions are controlled by switches located on a TAS
control panel or in combination with various other controls. A description
of controls is given in the Controls and Displays section of this Pilot’s
Guide.
ATC procedures and the “see and avoid concept” will continue to be the
primary means of ensuring aircraft separation. However, if communication is lost with ATC, TAS adds a significant backup for collision avoidance.
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TAS Introduction
TAS:
• Is compatible with the ATC System
• Determines if a threat exists from ATCRBS or Mode S Transponder
equipped aircraft
• Provides display and audio announcement to the crew
- Position information displayed on a traffic display
- Synthesized voice
• Incorporates sensor inputs and sophisticated algorithms to minimize
nuisance visual and aural annunciations.
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TAS Introduction
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TAS Theory of Operation and Symbology
SECTION I : THEORY OF OPERATION AND
SYMBOLOGY
Section I describes TAS Theory of operation and symbology.
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KTA 870/KMH 880 Pilot’s Guide
TAS Theory of Operation and Symbology
TAS OPERATION
TAS monitors the airspace surrounding your aircraft by interrogating the
transponder of the Intruding aircraft. The interrogation reply enables
TAS to compute the following information about the Intruder:
1. Range between your aircraft and the Intruder.
2. Relative bearing to the Intruder.
3. Altitude and vertical speed of the Intruder, if the Intruder is
reporting altitude.
4. Closing rate between the Intruder and your aircraft.
Using this data TAS predicts the time to, and the separation at, the
Intruder’s Closest Point of Approach (CPA). Should TAS predict that
certain safe boundaries may be violated, it will issue a Traffic Advisory
(TA) to alert the crew that closing traffic is nearby.
TAS SENSITIVITY LEVEL
TAS separates the surrounding airspace into two altitude layers. A different sensitivity threshold level for issuing TAs (traffic advisories) is
applied to each altitude layer. Lower altitudes have less sensitive TA
threshold levels to prevent unnecessary advisories in the higher traffic
densities anticipated at lower flight levels, i.e., terminal areas.
TAS has two sensitivity levels (SL) which are described in Table 1, TAS
Sensitivity Levels. SL A is invoked using the following order of precedence: (1) when the TAS aircraft is below 2,000 feet AGL (if equipped
with radio altimeter) OR (2) when the landing gear is Extended (no radio
altimeter installed). SL B occurs under all other flight conditions. Table
2, Typical Traffic Advisory Conditions for Sensitivity Levels describes
what conditions will cause a TA to be issued. If aircraft is not equipped
with either a radio altimeter or retractable landing gear, TAS will stay in
SL B at all times.
Sensitivity
Level
SL A In sensitivity level A, TAS performs surveillance and tracking func-
tions and provides traffic advisories. The conditions for sensitivity
level A are any one of the following:
(1) Own aircraft is in-flight and is below 2,000 feet AGL, if a radio
altimeter is installed.
(2) Own aircraft is in-flight and the Landing Gear is extended, if a
radio altimeter is NOT installed.
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TAS Theory of Operation and Symbology
SL B In sensitivity level B, TAS performs surveillance and tracking func-
tions and provides traffic advisories. The conditions for sensitivity
level B are based on own aircraft in-flight and:
(1) If radio altitude source is installed and own aircraft altitude is
above 2,000 feet AGL (radio altitude).
(2) If radio altitude source is NOT installed and own aircraft has
Landing Gear Retracted.
(3) If the aircraft has a fixed landing gear and no radio altimeter is
installed.
Table 1: TAS Sensitivity Levels
Sensitivity
Level
SL A The following conditions cause TAS to generate a TA in sensitivity
CONDITIONS FOR TRAFFIC ADVISORIES (TAs)
level A:
• TAS calculates that if current closing rate is maintained, separation of less than 600 feet in altitude between own and Intruder will
occur in 20 seconds.
• Separation between own and Intruder is less than 600 feet in altitude and less than 0.20 nautical mile range.
• NAR (Non-Altitude Reporting) Intruder is within 15 seconds or
0.20 nautical mile range.
SL B The following conditions cause TAS to generate a TA in sensitivity
Standby
or Fail • TAs are not generated.
Mode
level B:
• TAS calculates that if current closing rate is maintained, separation
of less than 800 feet in altitude between own and Intruder will
occur in 30 seconds.
• Separation between own and Intruder is less than 800 feet in altitude and less than 0.55 nautical miles in range.
• NAR (Non-Altitude Reporting) Intruder is within 20 seconds or
0.55 nautical mile range.
Table 2: Typical Traffic Advisory Conditions for Sensitivity Levels
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KTA 870/KMH 880 Pilot’s Guide TAS Theory of Operation and Symbology
TAS SURVEILLANCE VOLUMES
Surveillance volume is that volume of airspace within which other aircraft
with Mode S or ATCRBS transponders are tracked by own aircraft’s
TAS. The display volume is controlled by the operator and is not necessarily the same as the tracking volume.
(1) Range Tracking Volumes
The size of the range tracking volume is dependent on whether tracking
is occurring on a directional or OMNI antenna and attenuation levels
applied to the transmitted pulses from the TAS processor’s transmitter.
The typical range tracking volume is pictured as a circle.
The maximum range for TAS is 18 nm. However, there are instances
when you may see intruders out to 36 nm. TAS reduces range tracking
volumes in high density areas to reduce the number of receptions to be
processed by TAS and for interference limiting. TAS can track as many
as 45 aircraft and displays up to 30 of them.
(2) Altitude Tracking Volumes
TAS tracks other transponder equipped aircraft that are within a relative
altitude of +/-10,000 feet.
TAS AURAL INHIBITS
TAS will inhibit the aural annunciation using the following order of precedence: (1) below 400 feet AGL (if equipped with radio altimeter) OR (2)
when the landing gear is Extended (no radio altimeter installed). For
installations aboard aircraft with fixed landing gear and no radio altimeter
installed, the aural annunciation is not inhibited by the TAS processor,
unless weight-on-wheels indicates on the ground. The aural annunciation is enabled above 600 feet AGL in aircraft equipped with a radio
altimeter.
TAS TRAFFIC DISPLAY SYMBOLS
TAS will display three different traffic symbols on the traffic display. The
type of symbol selected by TAS is based on the Intruder’s location and
closing rate. Relative bearing and distance to the Intruder are shown by
the position of the Intruder symbol in relation to the own-aircraft symbol.
The symbols change shape and color as separation decreases between
your aircraft and Intruders to represent increasing levels of urgency.
The traffic symbols may also have an associated altitude tag that shows
relative altitude in hundreds of feet. A + sign and number above the
symbol means the Intruder is above your altitude. A - sign and number
beneath indicates the Intruder is below your altitude. A trend arrow
appears when the Intruder’s vertical rate is 500 feet per minute or
greater.
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KTA 870/KMH 880 Pilot’s Guide
TAS Theory of Operation and Symbology
No altitude number or trend arrow will appear beside any Intruder that is
Non-Altitude Reporting (NAR).
If TAS direction finding techniques fail to locate the azimuth of another
aircraft, a NO BEARING message appears on the screen when the
Intruder becomes a Traffic Advisory.
NON-THREAT TRAFFIC
+17
An open white diamond indicates that an Intruder’s relative altitude is greater than ±1200 feet, or its distance is
beyond 5 nm range. It is not yet considered a threat.
This traffic is 1700 feet above your own altitude,
descending at 500 feet per minute or greater.
+1700 Ft. and
Descending
PROXIMITY INTRUDER TRAFFIC
+10
A filled white diamond indicates that the Intruding aircraft is within ±1200 feet and within 5 nm range, but is
still not considered a threat.
This Intruder is now 1000 feet above your aircraft and
descending at 500 fpm or greater.
+1000 Ft. and
Descending
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KTA 870/KMH 880 Pilot’s Guide TAS Theory of Operation and Symbology
TRAFFIC ADVISORY (TA)
A symbol change to a filled yellow circle indicates that the Intruding aircraft is considered to be potentially hazardous. Depending upon TAS
sensitivity level, TAS will display a TA when time to CPA (Closest Point
of Approach) is 15 to 30 seconds.
+05
Here the Intruder is 500 feet above your aircraft. A
voice is heard in the cockpit, advising:
“Traffic, Traffic”
The crew should attempt to gain visual contact with the
Intruder and be prepared to maneuver upon visual
acquisition.
The crew should take no evasive action
based solely on the TAS display.
+500 Ft.
NO BEARING TRAFFIC
In installations with dual directional antennas with landing gear down,
when omnidirectional antenna is installed on the bottom of the aircraft, or
the intruder is located where the TAS cannot determine the azimuth of
the intruder, a “No Bearing” TA will be annunciated. If traffic can only be
seen by the bottom antenna as described above, a “No bearing” TA
would be annunciated as shown. Here the intruder is two nautical miles
away and co-altitude.
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OFF SCALE TRAFFIC
Threat aircraft (TAs) that are beyond the selected display range are indicated by one half of the traffic symbol at the edge of the screen. The
position of the half-symbol represents the bearing of the Intruder.
TA traffic on 5 mile range.
TAS Theory of Operation and Symbology
Same TA traffic; beyond selected range.
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KTA 870/KMH 880 Pilot’s Guide TAS Theory of Operation and Symbology
TAS INDICATIONS AND VOICE ANNOUNCEMENTS
“Traffic, Traffic”
Situation:
One Intruder is ahead near the 2:00 o’clock position, between 2 and 3
miles, 400 feet below your altitude and closing. TAS recognizes the
threat and issues a TA.
TAS TRAFFIC ADVISORY ANNUNCIATION (TA):
Aural Visual Crew Response
“TRAFFIC, TRAFFIC”
A filled yellow circle on the
Traffic Display
Conduct visual search for the
Intruder. If successful, maintain
visual acquisition to ensure
safe operation.
IMPORTANT:
The pilot should NOT initiate evasive maneuvers using information
on the Traffic Display only. Use the TA (Traffic Advisory) symbol to
visually acquire the Intruder and be prepared to maneuver upon visual acquisition.
Audio Announcements:
Synthesized voice announcements are issued by TAS over the aircraft
audio system. The following table lists all the audio messages, and advisories, in the TAS vocabulary.
Audio Messages
CONDITION ADVISORY MESSAGE
Traffic Advisory “TRAFFIC, TRAFFIC”
If Previous TA is Active “TRAFFIC”
Self Test Passed “TAS SYSTEM TEST OK”
Self Test Failed “TAS SYSTEM TEST FAIL”
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Intruders may be seen in surrounding airspace, but not on the TAS
display. The situations in which this may happen are:
TAS Theory of Operation and Symbology
• Most small aircraft have one transponder antenna located on the bot-
tom of the aircraft. When own aircraft is above one of these aircraft,
the transponder antenna can be shaded from the TAS interrogations.
When this occurs, the TAS interrogation may not reach the other aircraft’s transponder, or the other aircraft transponder’s reply may not
reach TAS’s antenna. A lack of replies prevents TAS from tracking
intruders. Transponder shading also occurs when the other aircraft is
maneuvering such that line of sight to its transponder antenna is
blocked.
• The TAS directional antennas have a bearing “cone of confusion”.
TAS is able to determine bearings for intruders that are located within
–10 degrees to +70 degrees elevation angle with respect to own aircraft’s horizontal plane for the top directional antenna (+10 degrees to
–70 degrees for a bottom directional antenna). Intruders that are
located outside of those elevation angles will be tracked with no bearing.
• TAS is unable to determine bearings for intruder tracked on the bot-
tom antenna when the own aircraft has a bottom monopole antenna
or a bottom directional antenna but the landing gear is extended. In
this case the intruder will be tracked, but not displayed, unless a
Traffic Advisory is issued against it.
• The other aircraft may have a poor transponder. Ground stations
have more gain and “hear” aircraft at farther distances than TAS.
• TAS is required to reduce transmitter power when in areas of high
density so that it does not adversely affect (overwork) other aircraft
transponders and prevent the ground ATC from tracking them. This is
known as Interference Limiting (IL). IL can reduce the nominal TAS
surveillance range to around 6 nmi. This means that TAS may not
detect a poorly performing transponder until it is much closer.
• TAS has a one-second update rate. When in areas of high density,
TAS may reduce its maximum surveillance range to either 10 nmi or
to the range of the 30th intruder in track plus 1 nmi. This allows TAS
to maintain its one-second update rate.
• TAS has an altitude surveillance volume of –10,000 feet to +10,000
feet relative to own aircraft’s altitude. Any intruders outside this volume are not a threat to own aircraft and therefore are not tracked by
TAS.
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