ALCOAST 146/25 - MAR 2025 COSPAS-SARSAT EMERGENCY LOCATOR TRANSMITTER DISTRESS TRACKING EMERGENCY PHASE STATUS

R 271800Z MAR 25 MID120001822786U
FM COMDT COGARD WASHINGTON DC
TO ALCOAST
BT
UNCLAS
ALCOAST 146/25
SSIC 16107
SUBJ: COSPAS-SARSAT EMERGENCY LOCATOR TRANSMITTER DISTRESS
TRACKING EMERGENCY PHASE STATUS
A. U.S. Coast Guard Addendum to the United States National Search
and Rescue Supplement (NSS) To The International Aeronautical and
Maritime Search and Rescue Manual (IAMSAR), COMDTINST 16130.2G
B. IMO Guidance for Autonomous Distress Tracking COMSAR 1/Circ.59/
Rev.1
1. The purpose of this ALCOAST is to inform Rescue Coordination
Centers (RCCs) of proper response procedures for Autonomous Distress
Tracking (ADT) Emergency Locator Transmitter-Distress Tracking
(ELT-DT) devices, in accordance with current USCG policy. It also
aims to minimize confusion between ELT-DTs and standard ELTs.
Current USCG policy regarding Emergency Locator Transmitters (ELT)
remains in effect.
2. BACKGROUND: While the International Civil Aviation Organization
(ICAO) established performance requirements for ADT, ICAO has not
specified which type of ADT device must be used on newly constructed
aircraft. The ELT-DT is the COSPAS-SARSAT-approved device which
meets the ICAO ADT requirements. It is important to note RCCs may
receive other ADT notifications from sources other than
COSPAS-SARSAT.
3. AREAs will receive ELT-DT notifications via two modes, including
SAROPS and the Location for Aircraft in Distress Repository (LADR).
The LADR sends only one email to inform each of the responsible
three stakeholders (RCC, air traffic control (ATC) and aircraft
operator (company)) that ADT information is in the LADR.
4. An ELT-DT is a type of ADT device designed to provide early
notification of a potential aircraft emergency while the aircraft is
still in flight. The ELT-DT COSPAS-SARSAT message header will
include the line "DISTRESS TRACKING ELT." In addition to possible
manual activation of the device, the following four criteria will
activate the ELT-DT in:
    a. Unusual attitudes
    b. Unusual speed conditions
    c. Collision with terrain warning [ground proximity warnings]
    d. Total loss of thrust/propulsion on all engines
If the conditions are corrected, the ELT-DT will transmit a
cancellation message. If the conditions are not corrected, the
ELT-DT will continue transmitting at the following intervals:
every 5 seconds for the first 2 minutes, every 10 seconds from
2 to 5 minutes, and every 30 seconds after 5 minutes. If the ELT-DT
is crash-survivable and the aircraft crashes, the ELT-DT will
transmit at 50 second intervals, similar to standard ELTs.
5. To prevent overwhelming the RCC with ELT-DT ADT notifications
via SAROPS, the RCC will only receive messages during the first
30 seconds (7 messages) after beacon activation, followed by one
message every 10 minutes thereafter.
6. Once LADR is fully operational, all data from ELT-DTs will be
available to those with an approved LADR account and login. Until
LADR is implemented, RCCs can contact USMCC to obtain additional
alert information.
7. POLICY: Following notification, AREAs will assume SMC for all
ELT-DT events in the alert emergency phase IAW REF (A),
Section 1.2.1. If the alert is confirmed distress, then the SMC
will be delegated to the District RCC for response coordination.
8. PROCEDURE: Following existing guidance in REF (A),
Section 3.4.4.6(i), regarding ELT distress alerts. AREAs should also
contact Air Traffic Control (ATC) facilities to determine whether
ATC is in contact with the aircraft. If aviation authorities confirm
an aircraft is in distress, AREA will upgrade to the distress
emergency phase, and SMC will shift to the appropriate SMC for
response coordination.
9. Controllers should note if an ELT-DT location appears stationary,
investigative work should include verifying whether the beacon is at
a major airport maintenance facility.
10. As ELT-DT devices come online with commercial airline
construction, there may be a high rate of false alerts due to human
error. U.S. SARSAT agencies, the FAA, ICAO, and COSPAS-SARSAT will
continue to prevent and mitigate these false notifications as they
become more frequent.
11. While AREAs will be the primary user of LADR, all U.S. RCCs are
expected to create a LADR account as a backup to Area Commands.
Information on creating a LADR account has been provided to the
AREAs and will also be available on the COMDT (CG-SAR) SharePoint
site.
12. SAR-3 created an ELT-DT 101 presentation available to RCCs for
reference, which can be found on the SAR-3 SharePoint site at:
(Copy and Paste URL Below into Browser)

https://uscg.sharepoint-mil.us/sites/cgsar/SitePages/CG-SAR-3-
(SARSAT).aspx

13. This message will be cancelled on 26 MAR 2026.
14. POC: LCDR Ashley Dufresne (Ashley.E.Dufresne@uscg.mil).
15. Ms. Dana S. Tulis, Director, Emergency Management
(CG-5RI), sends.
16. Internet release is authorized.