Section 9. Safety Logic Systems
Front-Line Manager/CIC Procedures
11-9-1. SYSTEM OPERATION
a. Safety logic systems are
software enhancements to the ASDE-3 and Airport
Surface Detection Equipment System - Model X (ASDE-X)
that predict the path of aircraft landing and/or
departing, and/or vehicular movements on runways.
Visual and aural alerts are activated when the safety
logic projects a potential collision.
1. Airport Movement Area
Safety System (AMASS) is a safety logic system
enhancement to the ASDE-3.
2. ASDE-X safety logic is a
system enhancement to ASDE-X.
b. The safety logic system
must be operated in a full core alert runway
configuration. (In ASDE-X, when rain configuration is
selected, it includes full core alerting
capabilities.)
c. In the event of a
Multilateration (MLAT) failure, ASDE-X will stay
operational. In this case, ASDE-X will operate in
radar-only mode. The system automatically transitions
to radar-only mode when it senses an MLAT fault. No
action is required by the operator to enable
radar-only mode.
1. The controller displays
will keep maps and track data. Tracks that were
currently being tracked when MLAT failed will keep
their data blocks while in the coverage area. Tracks
on arrival with ASR coverage will also keep a data
block while in the coverage area. Tracks moving from a
radar-only mode zone to a fully operational zone will
display the tracks as it enters the operational zone.
2. New tracks will start as
unknown icons and must be manually tagged to receive a
data block. ASDE-X safety logic processing is not
affected by radar-only mode operation. The system
automatically transitions to normal operation once the
MLAT subsystem is back online. Full core alerting
capabilities are provided in radar-only mode.
d. When ASDE-3 and/or AMASS
is in maintenance mode, AMASS data must be considered
invalid and the system must be taken offline. The
front-line manager/CIC must validate, upon resuming
normal AMASS operations, that runway configurations
and other user settings are adequate for operational
use.
NOTE-
Action to change AMASS online/offline status is a
technical operations function. ASDE-X safety logic
will automatically be disabled when the system is in
maintenance mode.
e. When a runway becomes
unavailable for aircraft operations for an extended
period of time, the runway should be entered as
“closed” in the safety logic system. Facility
procedures should be developed to address using the
safety logic system in this capacity.
f. Construction projects in
the vicinity of runways may cause nuisance or false
alerts. The National Airway Systems Engineering (NASE)
group may be able to provide an adaptation to filter
the affected areas from safety logic system coverage.
Facilities must contact NASE via email at
9-AMC-ATOW-ASDES@faa.gov, 30 to 45 days before the
construction is scheduled to begin to assist in
deciding if an adaptation is necessary.
g. ASDE-X false targets may
be temporarily track dropped after positive
verification has been done by pilot/vehicle operator
position report or controller visual observation. When
a false target is temporarily dropped, it must be
noted on FAA Form 7230-4, Daily Record of Facility
Operation.
REFERENCE-
FAAO JO 7110.65, Para 3-6-2, Identification.
h. The air traffic manager
may authorize a real target to be inhibited from
safety logic processing when the target will likely
generate a nuisance alert.
11-9-2. ENSURE STATUS
a. The front-line manager/CIC
is responsible for ensuring that the Safety Logic
System is set for the correct runway configuration.
b. The front-line manager/CIC
must ensure that the operational status of the Safety
Logic System is known to all operational personnel.
c. When a status change is
made to the Safety Logic System all personnel assigned
an operational position must be notified verbally.
d. When any status change is
made to the Safety Logic System it must be noted on
FAA Form 7230-4, Daily Record of Facility Operation.
Such status must be shown in the facility Status
Information Area (SIA). The front-line manager/CIC
must ensure that all outages are carried over on
applicable logs.
11-9-3. MONITOR ALERTS AND ENSURE CORRECTIVE ACTION
a. The front-line manager/CIC
must ensure that the Safety Logic System is monitored
and all alerts are complied with.
b. All Safety Logic System
alerts generated must be documented on FAA Form
7230-4. If unable to determine the origin of an alert,
treat the alert as false and notify Technical
Operations so that corrective action can be taken.
c. The purpose of logging
Safety Logic System alerts is to track the reliability
and performance of the system. Therefore, the Quality
Assurance Review (QAR) process must not be used for
false or nuisance alerts.
REFERENCE-
Pilot/Controller Glossary Term- Safety Logic System
Alerts.
11-9-4. RAIN CONFIGURATION
a. Due to the required
sensitivity of surface movement radars, numerous false
targets may be generated by moderate to extreme
precipitation. During these periods the ASDE-X and
AMASS Safety Logic Systems should be operated in rain
configuration. Should precipitation of this magnitude
occur or be imminent, rain configuration may be
applied to avoid the likelihood of false alerts.
b. When the event that led
to placing the system into rain configuration is no
longer a factor, the Safety Logic System must be reset
to a normal configuration.
NOTE-
When AMASS is in rain configuration all safety logic
alerts with the exception of arrivals to a closed
runway are inhibited and AMASS is not in full core
alert status.
11-9-5. LIMITED CONFIGURATION
a. Under certain
circumstances, there may be a need to operate the
Safety Logic System in limited configuration. The
limited configuration must only be used to temporarily
inhibit persistent false alerts. The term “persistent
false alert” refers to frequent false alerts caused by
continuous or repetitive circumstances. False alerts
caused by random events or circumstances of short
duration are not considered “persistent false alerts.”
The determination of “persistent alerts” is at the
discretion of each front-line manager/CIC.
b. Due to the required
sensitivity of surface movement radars, numerous false
targets may be caused by precipitation of moderate or
greater intensity. Should precipitation of this
magnitude occur or be imminent at locations where ASDE
does not have rain configuration availability, limited
configuration may be applied to avoid the likelihood
of false alerts.
c. When it is necessary to
operate the ASDE-X Safety Logic System in limited
configuration due to “persistent false alerts,” notify
Technical Operations so that corrective action can be
taken.
d. When an AMASS false alert
is received, limited configuration must only be used
until Technical Operations verifies that the system is
functioning properly and that the data necessary to
analyze the alert has been obtained. Analysis and
resolution of the circumstances surrounding the false
alert will be determined by Technical Operations at a
later date.
e. When limited
configuration is applied, it must be noted on FAA Form
7230-4, Daily Record of Facility Operation, including
the reason for the configuration change. Ensure that
all limited configurations are carried over on
applicable logs.
NOTE-
1. For AMASS, the limited configuration
disables all alerts except arrivals to a closed runway
and is not considered full-core alert status.
2. For ASDE-X the limited configuration
disables all alerts except arrivals to and departures
on a closed runway and is not considered full-core
alert status.
11-9-6. WATCH CHECKLIST
The Safety Logic System status must
be included in the facility watch checklist. At a
minimum, the following items must be reviewed:
a. Operational status.
b. Runway configuration.
c. Presentation of the
Safety Logic System data on all ASDE system displays.
d. When test button is
activated, the aural alert is heard, and the speaker
volume is adequate. |
