Inmarsat Swiftbroadband Oceanic Safety Development Programme

ACP WG-W/4 WP-21

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14 – 16 Sept 2011

AERONAUTICAL COMMUNICATIONS PANEL (ACP)

Fourth Meeting of the Working Group of the Whole

Montreal, Canada 14 – 16 September 2011

INMARSAT SWIFTBROADBAND OCEANIC SAFETY DEVELOPMENT PROGRAMME

(Presented by Inmarsat)

1.INTRODUCTION

1.1The Inmarsat SwiftBroadband service has been in operation since October2007, providing voice and broadband data communications to airline passengers. At present, aeronautical safety messages, such as FANS/ACARS data, are supported by Inmarsat’s Classic Aero services. There is an ongoing program of work to enhance SwiftBroadband to enable it to meet the requirements of a safety service, as described within this paper. SwiftBroadband Oceanic Safety services will support FANS/ACARS data with priority, pre-emption and precedence applied. The traffic will be separated from the cabin communications traffic, and the SwiftBroadband Oceanic Safety Services terminal will also be able to provide high bandwidth Internet Protocol (IP) data and voice to the cockpit, utilising priority and pre-emption of messages to ensure safety messages reach the cockpit unhindered by the commercial communications traffic load to the cabin. This high bandwidth data capability will be extensible to support the Aeronautical Telecommunications Network (ATN) and future concepts of operation in Air Traffic Management (ATM) as there is a shift from tactical to strategic management of air traffic and the balance of communications messages shifts from voice to data.

2.DISCUSSION

2.1SwiftBroadband Oceanic Safety Service Objectives

2.2The ICAO Global Operational Data Link Document (GOLD) defines the Required Communications Performance (RCP) values for the continuity, availability, integrity and transaction timesof data communications. The values are derived from safety assessment and are set to ensure the provision of a safe service under specific operational scenarios. However, the GOLD includes more stringent availability and other specific criteria where it would be required to support a more demanding operational requirement. An example of such an operational requirement is the plan to reduce the minimum separation between aircraft on oceanic routes.

2.3Airlines and Air Traffic Service Providers are very keen to increase airspace capacity, and operational and fuel efficiency, whilst maintaining or enhancing safety. To achieve these objectives, there are moves at international level to allow reduced minimum aircraft separations in oceanic and remote areas, in regions of controlled airspace where the satcom performance is proved to be sufficiently available and reliable. The intention is to move from the current typical minimum in-trail separations of 10 minutes/80 NM (Nautical Miles), and 60 NM between tracks, to an in-trail separation of 30 NM and 30 NM between tracks: so-called 30/30 NM separations.

2.4To achieve such reduced separations, there is a need for a greater frequency of aircraft position reporting, and to ensure a higher datalink service availability. This is required to permit controller intervention, at any time, in the event that it is required if aircraft begin to stray from the track in their flight plan. This in turn demands an enhancement of the minimum performance level of the communications systems supporting Air Traffic Service (ATS) voice and data safety services.

2.5The RCP requirement for the availability of anoceanic datalink communication system in support of a safety service is 99.9% over a 12-month period, (the ‘safety’ requirement). To meet the more stringent RCP requirement in support of 30/30 separations, the end-to-end service availability of the communication system must be at least 99.99% over a 12-month period, (the ‘efficiency’ requirement). This is a challenging requirement for a ‘single path’ communications system and the implication is that the satellite communications system includes appropriate redundancy, fail-over and alternate routing mechanisms to mitigate the potential temporary failure of a range of different system constituents.

2.6Like the Inmarsat Classic Aero services, SwiftBroadband Safetywill meet the safety requirement of 99.9% availability. In order to meet the more stringent efficiency requirement of 99.99% availability on oceanic routes, Class 6 High Gain Antenna (HGA) terminals will have the capability to fail-over to the Classic Aero service on the I4 network. Although fallback to Classic Aero over I4 will be the preferred initial fallback mode, fallback to Classic Aero over I3, for as long as the networks are available,is also planned to be accommodated. Figure 1 shows the options for meeting the differing safety and efficiency requirements.

Figure 1: Product options for Meeting the RCP240 Safety and Efficiency Requirements

2.7The Inmarsat avionics manufacturing partnership and airframers have expressed their support in providing the safety service capability across this product set.

2.8SwiftBroadband Oceanic Safety System Description

2.9SwiftBroadband uses the Inmarsat I4 satellites and Inmarsat’s Broadband Global Area Network (BGAN). A diagram of the SwiftBroadband Oceanic Safety high level architecture is given in Figure 2, which shows the in-built redundancy of the design.

Figure 2: SwiftBroadband Oceanic Safety High-Level Architecture

2.10In addition to the commercial services currently provided bySwiftBroadband, SwiftBroadband Oceanic Safety will provide the following safety services:

FANS/ACARS data;

2 voice channels to the cockpit;

Prioritised IP data to the cockpit.

2.11In order to enable these additional services, changes need to be made to the BGAN ground infrastructure and to the existing aircraft terminals. These changes will enable the prioritisation and pre-emption of voice and data messages to the cockpit, to ensure that safety messages are not hindered by the commercial communications traffic load.

2.12To use SwiftBroadband Oceanic Safety services, the Satellite Data Unit (SDU) on the aircraft will need to be updatedto incorporate an ACARS air gateway (shown on the right of Figure 2) and appropriate interfaces to the cockpit avionics.The interfaces will be the same as they are for Classic Aero, thus minimising the required changes onthe aircraft.

2.13The most significant changes will be to the ground network. The planned architecture requires a new ACARS ground gateway (shown on the left of Figure 2) to be built and installed at the BGAN satellite access station sites in order to route ACARS data traffic between the aircraft and Air Traffic Service Providers (ATSPs) and Airline Operational Control (AOC) centres on the ground.

2.14SwiftBroadband Safety Services – Benefits to both Airline operators and ANSPs

2.15SB200 Low-Cost Safety Terminal:

2.16Due to their size and weight, Inmarsat’s SwiftBroadband Class 6 and 7 user terminals primarily addressthe needs of larger business aviation, government and air transport aircraft. Inmarsat understands there is significant customer interest in smaller, lighter aircraft antenna/avionics packages and lower hardware cost, to bring satellite communications to mid-sized business aircraft and even General Aviation (GA).

2.17To meet this market demand, Inmarsat introduced the SB200 service family, with the Class 15-1 user terminal being the first into servicein October 2010, offering a maximum of 200kbps throughput but limited to operation down to 20 degrees elevation. The evolution of this SB200 terminal into the Class 15-2 will see a number of enhancements, the main one being improved coverage down to 5o, which aligns to the coverage of the existing Inmarsat products.

2.18As shown in Figure 1, the Class 15-2 terminal, like the Class 6 and Class 7 terminals, will meet the RCP requirements for a safety service, but may not meet the more stringent availability requirements for efficiency at this stage of development.

2.19End User Service Benefits:

2.20Inmarsat believes that the end-user prices for ACARS messaging on SwiftBroadband can be delivered at rates at least one third lower than the equivalent tariffs on our Classic aero service.

2.21ANSPs will be able to consider new concepts of operation for aircraft equipped with the SBB/Classic product targeting the RCP240 communications performance.

2.22The SB200 safety terminals will offer airlines smaller , cheaper, lighter product options.

2.23Prioritised IP connectivity offers the opportunity to introduce new ATS and meteorological services to the evolving Electronic Flight Bag products.

2.24It is possible to have this capability available for validation trials in a relatively short timeframe due to the fact that ground and avionics interfaces are maintained to the maximum possible extent, thus the benefits of ‘always-on’ IP communications can be brought to the aviation community.

2.25Standards Development

2.26InJanuary 2009,within RTCA SC-222 the Inmarsat partnership beganthe process of developing Minimum Aviation System Performance Standards (MASPS) and Minimum Operational Performance (MOPS) for SwiftBroadband Safety services using the ICAO GOLD RCP methodology as a baseline. As a result by the beginning of 2012 these documents will be mature enough to assist in the development of the appropriate WG-M material.

2.27Inmarsat is also standardizing the BGAN system within the ETSI.

2.28Programme Timeline

2.29The key target milestones of the SwiftBroadband Safety programme are given in Table 1.

Description

Date

ACARS Ground Gateway final acceptance

end 2012

Class 6 & 15-2 user terminal factory acceptance

Feb 2013

Start of FANS evaluation

Feb 2013

FANS evaluation complete

Feb 2015

Table 1: Programme Milestones

2.30Inmarsat and its partners will be working to build trials partnerships during 2012 in order that validation trials could begin in Q1 2013. Inmarsat and its communication service providersintend to present the plans for trials and validation into the FAA PARC and ICAO regional datalink groups.

3.ACTION BY THE MEETING

3.1Supported by avionics manufacturers, airframers and communications service providers the ACP WGW is invited to:

3.2Approve the initiation of a work programme to develop a Technical Manual for the SwiftBroadband Oceanic Safety System meeting the aviation requirements for ICAO AMS(R)S and additionally any accompanying implementation documentation required.

3.3To utilise,where possible, the standards already in development in the RTCA/EUROCAE (SC-222).

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