IBAC Technical Report Summary
Subject: NAT Operations and Air Traffic Management
Meeting: North Atlantic (NAT) Air Traffic Management Group 38th Meeting (ATMG/38)
IBAC File:
Reported by: Brian Bowers
Summary: ATMG/38 was held at the European and North Atlantic (EUR/NAT) Office of ICAO in Paris, France 12
to 16 September, 2011.
The NAT Safety Oversight Group (NAT SOG) has formed the Data Link Exemption Task Force (DLM Exemption
TF); therefore the NAT ATMG has agreed to recommend to the NAT IMG that the task of preparing a draft concept
of operations for accommodating non-equipped aircraft in relation to the NAT Region data link mandate and implementation of reduced lateral separation, be deferred until the Task Force has completed its work.
The ATMG has agreed to recommend to the NAT IMG that it coordinate with the NAT SOG to obtain updates on
whether an approval granted by Canada, Iceland, Norway or Portugal would permit ATS services based on ADS-B to
be provided by all of those States, without a requirement for each of them to grant their own approval.
It was previously agreed the NAT data link service could be declared fully operational when the NAT Data Link
Monitoring Agency (NAT DLMA) was fully functional. Although the NAT DLMA is already providing its services,
several NAT service providers are still in the process of upgrading their ground automation systems in order to be able
to provide data to the NAT DLMA in the format required. The completion of these actions will allow the establishment of a fully functional NAT data link monitoring system and enable the declaration of the NAT data link service
fully operational.
Operators are encouraged to seek RNP approvals for appropriately equipped aircraft and RNP 4 approvals should be
sought when possible.
ATS surveillance services based on ADS-B will only be provided to aircraft which meet, at a minimum, the requirements specified in the European Aviation Safety Agency (EASA) Acceptable Means of Compliance (AMC) 20-24 or
equivalent. Canada will maintain a shared eligibility list on behalf of the ICAO NAT Region. The US will require
compliance with the more stringent requirements specified in AC 20-165 in order for aircraft to be provided with ATS
surveillance services based on ADS-B in airspace where the US provides such services.
The NAT SPG has agreed that a mechanism should be established to develop a draft EUR and NAT ATM contingency
plan to respond to a nuclear emergency.
Operators have expressed a need for simplified and centralized information to support their decision making in relation
to Volcanic Ash Clouds. This could include graphical depictions/formats. The International Volcanic Ash Task Force
(IVATF) is expected to include recommendations for changes to the Volcanic Ash Contingency Plan – EUR and NAT
Regions (NAT Doc 006, Part II / EUR Doc 019) and any recommendations will be forwarded to the NAT IMG.
The estimated vertical collision risk in NAT RVSM airspace has again exceeded the TLS of 5 x 10-9 fapfh. Failure of
inter-center ATC coordination continues to be one of the significant contributors to the risk in the region. The NAT
SOG has urged ANSPs to pay particular attention to this problem. The full implementation of ATS Interfacility Data
Communications (AIDC) capabilities will contribute to the resolution of this issue, as will the implementation of the
conformance monitoring applications supported by ADS-C.
The NAT IMG had been tasked to determine the circumstances which would permit the elimination of the requirements for HF voice in the NAT Region. The conclusion of the assessment was that the requirement for HF voice in the
NAT Region would remain in the foreseeable future, largely depending on the level of safety and service continuity
requirements.
The representative from IATA reiterated IATA’s desire, that the vertical limits of the exclusionary airspace for the
phased implementation of the NAT data link mandate be flexible. The NAT IMG noted the NAT ATMG has ex-
pressed concerns regarding the safety of such a process, and has agreed that the possibility be examined in more detail
for subsequent phases. The process should assess possible ways that such flexibility could be implemented while
identifying possible hazards and determining whether it will be possible to mitigate the hazards.
No further work will be undertaken to update the NAT Service Development Roadmap until an alternative format for
the Roadmap has been developed. France has agreed to coordinate with the UK to develop an alternative format which
will address concerns.
The NAT IMG has endorsed a suggestion that an “update” type of NAT OPS Bulletin could be produced and maintained, with the cooperation of all its contributory groups. One (or more) States could also offer to issue a NOTAM if
it was deemed desirable to notify a change as widely as possible. This system would be considered on a case by case
basis.
It is a current requirement for flight crews to REPORT LEAVING if the flight is operating in RVSM airspace. These
reports are important for the detection of vertical errors. It has been further noted that when using data link communications, the report can not be activated from the cockpit unless a corresponding request is included in the uplink instruction from ATC. The NAT SPG has urged each State and ANSP to apply this procedure.
The US representative informed the NAT ATMG that it had completed an initial draft proposal for amendment to the
NAT SUPPs to support its plans to implement 50 NM longitudinal separation, 30 NM lateral and 30 NM longitudinal
separation between suitably equipped and authorized aircraft pairs in the New York Oceanic Flight Information Region in late 2012. “Canada feels the goal of ICAO working groups is to create harmonization and consensus, not
validate ANSPs in providing different separation standards within its area of responsibility.” The United States indicated that there were currently many different standards applied to aircraft in the NAT Region. The planned implementation would not be mandatory and would not include a route restructure. IATA expressed concern that a potentially dis-harmonious situation could be caused within the ICAO NAT Region by the implementation of 50 NM longitudinal and 30 NM longitudinal and 30 NM lateral separation standards in the New York Oceanic FIR. The issue will be
brought to the attention of the NAT IMG.
The trial implementation, of reduced longitudinal separation of 5 minutes between ADS-C equipped aircraft has been
in operation in the Gander and Shanwick Oceanic Control Areas (OCA) since 31 March 2011. It was noted that it
would be beneficial for operators to be more aware of this trial and the fact that the application of RLongSM could
facilitate accommodating requests to adjust speed in addition to granting requests to climb or descend.
Canada advised approximately 33% of the traffic operating in the planned ADS-B service area is on the eligibility list.
Operators issued an A353 Ops Spec by the US FAA are placed on the eligibility list when the FAA advises Transport
Canada, that the Ops Spec has been issued.
CANADA advised the first of the planned ADS-B installations in southern Greenland has been activated and test data
is being evaluated. Portugal advised that its ADS-B multilateration project will be completed in November 2011.
Testing will begin in 2012, but it is not possible to forecast an operational date. Norway is planning to implement
ADS-B for offshore operations. They are also considering the possibility of implementing ADS-B to provide surveillance coverage in the northern part of their airspace, where radar coverage is not available. ISAVIA has contracted
with EUROCONTROL to conduct In Trail Procedure (ITP) trials in radar coverage to collect data. A number of airlines have equipped their aircraft to support ITP and the intention of the trial is to validate the safety assumptions and
the supporting procedures. Preparation will be completed in 2011 and the trial is expected to begin in early 2012.
The NAT ATMG was advised of the result of assessments, carried out by the UK and Canada of whether it would be
possible to modify systems and procedures to only transmit the route in an Oceanic Clearance, when that route differed
from the route in the flight plan. The conclusion was that this would be a significant change to the programming for
the FDPSs, which would require considerable validation and verification. Various concerns were noted with regards to
the risks this concept could introduce, and the mitigations required. Much of the concern involved the inconsistent
filing and re-filing practices that currently exist in the aviation industry. It has been identified that issuing the cleared
route for every oceanic clearance is in itself a safety mitigation in that it forces a cross check between what is contained in the ATC system and what is contained in the aircraft FMS. This view was supported by Iceland, Ireland and
Norway.
It was agreed to recommend to the NAT IMG that NAT ATMG/39 take place from 5 to 9 September March 2012 or
12 to 16 March 2012, depending on the availability of meeting space, in Reykjavik, Iceland and that NAT ATMG/40
be planned to take place in Paris. It was agreed to seek the NAT IMG’s endorsement of New York, as the venue for
NAT ATMG/41.
Implication for Business Aviation:
Note. A Data Link Mandate Exemption Task Force (DLM Exemption TF) has been formed and the task of preparing a
draft concept of operations for accommodating non-equipped aircraft in relation to the NAT Region data link mandate
and implementation of reduced lateral separation has been deferred until the TF has completed its work.
Note. Operators are encouraged to seek RNP approvals for appropriately equipped aircraft and RNP 4 approvals
should be sought when possible.
Note. The issues surrounding the use of ADS-B operations in the NAT including the fact that operators issued an
A353 Ops Spec by the US FAA are placed on the ADS-D eligibility list when the FAA advises Transport Canada, that
the Ops Spec has been issued.
Note. The IVATF is expected to include recommendations for changes to the VAC Plan – EUR and NAT Regions
(NAT Doc 006, Part II / EUR Doc 019).
Note. The estimated vertical collision risk in NAT RVSM airspace has again exceeded the TLS of 5 x 10-9 fapfh.
Note. The requirement for HF voice in the NAT Region will remain for the foreseeable future
Note. The issues around the planned use of 50 NM longitudinal separation minimum and a 30 NM lateral/30 NM
longitudinal separation minimum between suitably equipped and authorized aircraft pairs in the New York Oceanic
Flight Information Region in late 2012.
Note. The Gander/UK trial implementation of reduced longitudinal separation of 5 minutes between ADS-C equipped
aircraft on the NAT has been in operation in the Gander and Shanwick Oceanic Control Areas (OCA) since 31 March
2011. It would be beneficial for operators to be more aware of this trial and the fact that the application of RLongSM
could facilitate accommodating requests to adjust speed in addition to granting requests to climb or descend.
Decisions Required: On the timely acquisition of equipment, degree of training and certification required to meet
the requirements to efficiently continue accessing NAT airspace.
Decisions are required on ADS-B out, RNP, ADS-C, and CPDLC usage certification.
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