Onair Issue 21

8/13/2019 Onair Issue 21

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This issue highlights some of the work Helios has been doing in software development,

technology assessments, cost-benefit analysis and communications support. The focus

of many of these projects has been on improving safety. This is hardly surprising given

the acknowledged need for new systems to support growing demand in all forms of travel.

Another subject close to our hearts is Galileo, the European satellite system (see

news on the Fidelity project in HOT AIR!). In a recent communication, the EC reinforced

Europe's need for Galileo, but also outlined the problems being faced across the

programme. Back in 2000, it was decided that a Public Private Partnership offered the

best means of financing full deployment based upon a number of key assumptions. It is

now apparent that many of these assumptions regarding design risk and liability have

not materialised. The EC now recommends that the public sector should finance all

capital costs, leaving a concessionaire responsible for long term operations. We wait to

see at the end of this month whether the European Parliament and Council will follow

this recommendation or not.

Finally, we are delighted to announce that ON AIR! is going electronic! Our regular

readers will soon see this issue appear in their inbox. If you would like to join them and

receive future copies by email, do get in touch at

[email protected].

News and Information

from Helios

CONTENTS

Anew interactive Safety Screening Tool developed by

Helios and NLR as part of the SESAR work package

“Safety Regulation” has been welcomed by users.

The tool aims to improve safety considerations in

early systems design. It does this by identifying those

changes that have the potential for major effects on

safety (positive or negative). It then prioritises these for

more detailed safety assessment studies.

The tool helps users screen projects based on 17

‘safety fundamentals’ drawn from three different

perspectives on safety:

1. System safety performance

2. Safety management aspects

3. Operational safety aspects

The screening method is able to generate rapid,

ATM SYSTEM SAFETY

Software success

IP FOR AVIATION

New solutions for 2020+

MARITIME AIS

New technology assessed

SAFETY NETS

STCA and ACAS

HOT AIR!

Our news section

OFF AIR!

Puzzle competition

S U M M E R 2 0 0 7

☞

Mike Shorthose, Managing Director

Spotlight on safety

high-level discussion of safety issues raised by ATM

system changes and is suitable for the concept planning

stage. Says EUROCONTROL project manager Oliver

Straeter: “It should help foster a proactive and shared

understanding of safety, and avoid cost-intensive

recovery or delays in project delivery.”

Helios was responsible for software development

and NLR for content and project management. Adds

Straeter: “This tool is currently in active use and has

been warmly received. It is user-friendly and robust. We

are delighted with the results, and are planning further

developments in 2007.”

ATM system safetySoftware success Features of the SESARSafety Screening Tool

● Built in Excel● Designed for ‘projection’ in a work-

shop environment● Incorporates a ‘Question Navigator’

enabling easy navigation and overview● Recording of answers● Graphical display of automatically

calculated results● Advanced question structure:

hierarchy, mapping and automatic

routing● All data stored in easy-to-understand

spreadsheets


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News and Informat ion from Hel ios

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Following earlier studies investigating the use of Internet

Protocols (IP) for future air-ground data link

applications, a new study led by Helios has identified two

previously unexplored solutions.

EUROCONTROL commissioned the study to assess the

feasibility of using IP to support the next generation of ATS

and AOC applications, focusing on technical and security

issues brought about by the mobility of aircraft and the

need to communicate with different ground stations and

networks.

ICAO studies had previously concluded positively on the

feasibility of IP for providing aeronautical air-ground

network connectivity for safety-related ATC services. As

well as exploring the existing mobility solutions identified

by ICAO, including the use of routing protocols and Mobile

IPv6, the Helios team identified two technically feasible

solutions that had not previously been considered: a

solution based on moving IPsec tunnels, and a so-called

Link Layer mobility solution. These have since been

accepted by ICAO as candidate solutions.

IP is already being used in several non safety-critical

ground-ground ATS applications. The aim of this work was

to build on the recommendations of the ICAO study and to

identify the technical solutions best suited to aviation. Says

Helios project manager Dr Andrew Ives: “The reason for

looking at IP for aviation is that it potentially allows

benefits from the latest developments in industry. But using

IP also presents a host of technical challenges related to

security and mobility - as well as avionics certification

issues - that need to be resolved.”

IP is being considered to support future, more advanced

ATC applications such as trajectory-based negotiation, and

is intended for operation over new air-ground data link

technologies expected to be deployed in 2020 or beyond. In

the meantime, the ATM community is implementing the

Aeronautical Telecommunication Network (ATN) for ATS

air-ground data link communications.

The six-month study was carried out by a consortium

comprising Ericsson, SITA, Sofréavia, LFV, Rockwell Collins

and DLR. For further information please contact Dr Andrew

Ives at [email protected]. Alternatively, visit

the EUROCONTROL website to access the study deliverables:

www.eurocontrol.int/communications/public/news/news_

141106.html.■

IP for aviation

New solutions for 2020+

The SESAR Safety Screening Tool was developed for

EUROCONTROL as a contribution to the SESAR Definition

Phase, which is a project of EUROCONTROL co-funded by the

EC TEN-T programme. For more details about the tool

contact Andrew Burrage at Helios (andrew.burrage@

helios-tech.co.uk) or Oliver Straeter at EUROCONTOL

([email protected]). Or visit

www.eurocontrol.int/safesky.■

Andrew Burrage

Andrew has been working at Helios since

February 2006 where he has worked on

numerous software and analysis projects. For

the SESAR Safety Screening Tool he was solely

responsible for the software development on

the tool. Previously Andrew worked on the

validation of the later stages of the CAPT surveillance software tool (see ON AIR! Autumn

2006). He is also the main developer on an

internal web-based account tracking package

and a key team member in Helios’ study into

mitigation of Interrogator Code (IC) conflict.

Options considered

Routing protocols – A translation of the existing ATN

approach into the IPS where routers throughout the

network distribute the required IP address.

Mobile IPv6 – A standard defined in IETF to enable

seamless roaming. All communication is routed through

one Home Agent as the aircraft travels.

IPsec tunnels – Involves the setting up of an IPsec

‘tunnel’ as a link between an aircraft and the desired

ground system. An aircraft moving to an area with a

different network sets up a new IPsec tunnel and then

dismantles the previous one.

Link Layer mobility – Based on 3GPP protocols as usedfor mobile phones. Provides seamless mobility within a

network and involves service providers exchanging IP

addresses at network boundaries.


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Testing the wind? - Helios and NATS have recently

won a contract from the EUROCONTROL ExperimentalCentre to develop validation plans for Wake Turbulence

concepts such as Time Based Spacing and Crosswind Departures.

The work will comply with the European Operational Concept

Validation Methodology. This reflects the strengths of the

involved parties, and builds on Helios' operational concept

development expertise in areas such as Airborne Surveillance,

Continuous Descent Arrivals, and 4D trajectories.

Fragmentation explained, defragmentation

explored - This is the theme of our conference taking

place on 27-28 November 2007 in central London. Key industry

decision makers are speaking. This is THE topic on everyone’s

agenda today in driving forward ATM policy and system

evolution in Europe. Put the dates in your diaries now and if

you would like to pre-register, contact [email protected].

Fidelity news - The Fidelity project continues on track.

Helios is the project manager for a pan-European

consortium which is delivering the Time Service Provider (TSP)

for Galileo. The customer is the GNSS Supervisory Authority

(GSA). The development of this vital component of the

European GNSS is continuing right on schedule. In May Helios

ran the successful Development Key Point 1 (DKP 1) meeting.This looked at all aspects of the implementation of the TSP

facility and also the planning for future developments. The

GSA is very satisfied and Fidelity are now bang on target for

achieving the next major milestone at DKP 2 in July.

New arrivals - We welcome Dr Branka Subotic and

Nick Clyburn to the team. Branka is an expert in safety

and human factors in ATM and recently completed the final

stage of her PhD in controller recovery from equipment failures

in ATC. She joins the Operations and Safety team working on

safety cases and future concept development and adds Serbian

to the 9 other languages spoken by our multinational team!

Nick joins us from Strike Command, where he has been working

as an internal management consultant for the RAF. As well as

bringing new skills to the company, he also reinforces our

growing operations team with his background in air traffic

control.

Surveillance training success - Our June ’07 public

training courses focussing on secondary surveillance

technologies (Mode S, ADS-B and Multilateration) ‘sold out’

with record attendances. We are now planning a training week

on navigation technologies and another on communications

technologies – all for engineers and technicians. To register for

latest information contact [email protected].

Beaming buoysNew RF technologyassessed

Today mariners typically use radar to locate aids to

navigation, with traditional visual identification of

buoys and lighthouses as a fallback. Now a new radio

frequency broadcast technology is being assessed that has

the potential to provide more accurate position information,

positive identification of the aid to navigation and other

useful data such as sea conditions.

Called AIS (maritime Automatic Identification System),the technology is being evaluated by the General Lighthouse

Authorities whose role it is to provide Aids to Navigation

(AtoN) to mariners – and Helios has recently completed a

study for them which defined the AIS service availability

requirements and made system design recommendations.

The study was carried out in four steps:

1. Define the AIS AtoN service and propose a definition

for the service availability.

2. Identify the system architecture for the provision of

the AIS AtoN service.

3. Carry out a Failure Mode and Effect Analysis (FMEA)

to identify the different failure modes.

4. Carry out a Fault Tree Analysis (FTA) using the FMEA

output to calculate the overall failure rate.

This process enabled the General Lighthouse Authorities

to identify the critical areas of the system architecture and

service provision that may need to be addressed prior to

implementation. Furthermore, the FTA will enable them to

specify performance requirements on separate parts of the

AIS AtoN system to ensure that a target level of availability

is achieved. For more information on this project, contact

[email protected].■

FTA and FMEA explained

Failure Mode and Effect Analysis (FMEA) and Fault Tree

Analysis (FTA) are two common techniques used for

carrying out safety assessments.

FMEA is a systematic method of identifying the

failure modes of a system and determining the effects on

the next higher level of the design.

FTA is a “top-down” system evaluation procedure in

which a model for a particular undesired event is formed

and then evaluated.


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Recent aviation accidents have highlighted the need to

strengthen ATC safety nets and Helios has been

supporting EUROCONTROL’ s Safety Nets team in analysing

the issues and communicating the actions.

In 2004 and 2005 EUROCONTROL undertook

comprehensive surveys to assess the status of current

practices in ground based safety nets. The next step was to

develop specifications and

guidance materials to support

standardisation, with a specificpriority for STCA (Short Term

Conflict Alert). During 2006 Helios

assessed the economic impact of

standardising STCA throughout

Europe. Helios also developed a

spreadsheet model that enabled

individual Air Navigation Service Providers to assess the

cost for their organisation to obtain standardised STCA.

While this was going on, other members of Helios worked

with the Safety Nets team to raise the profile of theactivities, developing presentations, posters, graphics and

helping prepare stakeholder workshops.

Now in 2007 Helios is just starting working with the

team on their next challenge: to raise the levels of

awareness and understanding between controllers, pilots,

safety and management staff about safety nets, and how

they interact with each other.

Says EUROCONTROL’s Ben Bakker: “The average pilot

doesn’t know much about STCA and may believe or assume

that STCA and ACAS are coordinated. They are not. This is

part of our work to raise awareness and understanding of

the issues involved across the aviation community.”

STCA and ACAS interaction will be the focus of further

studies during 2007-2010. The subject was addressed in

some detail at a workshop held by EUROCONTROL and the

Swiss Federal Department of the Environment, Transport,

Energy and Communication (DETEC), which was attended

Safety nets for ATCSpotlight on STCA

and ACAS

by 36 renowned experts in this area of safety. The workshop

report, more information on safety nets and the work done

by EUROCONTROL in this area can be found at

www.eurocontrol.int/safety-nets. Or contact

[email protected].■

For further information, contact Mike Shorthose by email:

[email protected], telephone: +44 1276 452811 or visit

our website www.helios-tech.co.uk.This newsletter has been written for the interest of our clients and colleagues.

We believe the facts are correct at the time of printing, but cannot be held

responsible for any errors or omissions. Please send change-of-address details

to [email protected]. Helios Technology Limited, Chamberlain House,

High Street, Bagshot, Surrey, GU19 5AE, UK.

Helios is a technical and business consultancy working in airports, air

traffic management and navigation markets. We help our customers solve

problems and implement technical and operational solutions that willimprove corporate performance. Our team has a range of expertise

covering research, planning, simulations, feasibility studies, cost benefit

analysis, procurement support and safety studies. Our knowledge covers all

of the technologies that support air traffic management, as well as satellite

navigation and advanced communication systems.

The lost buoy!Two motorboats leave a pier simultaneously,

the HMS Tinker downstream and HMS Bell

upstream, with the same motive force. As

they leave, a life buoy falls off HMS

Tinker and floats downstream. An hour

later both ships are ordered to reverse

course. Which boat arrives at the buoyfirst or do they arrive at the same time? Please provide a

brief explanation with your answer.

The answer will be published in the next edition of ON AIR!.

Please send your solutions to laurette.royer@helios-

tech.co.uk. All entries must be received by 30 September

2007. As usual, we will give a bottle of champagne to the

first correct answer drawn at random after this date. Good

luck to everyone!

And the winner is …

The correct answer to the puzzle in the Spring edition of ON

AIR! was 8:25am. The car was scheduled to reach the

station at 8:30am. When it met the engineer, it saved 10

minutes (5 to get to the station and 5 to come back to the

meeting point). Therefore the engineer met the car at

8:25am. Well done to Nigel Eite of the UK CAA who wins the

champagne.

Safety nets in briefSTCA and ACAS are well-established safety nets that both

exclusively serve the purpose of preventing collisions

between aircraft during airborne phases of flight.

STCA (Short Term Conflict Alert) alerts the air traffic

controller who then immediately assesses the situation,

determines the best course of action and gives appropriate

instructions to the pilots concerned.

ACAS (Automatic Collision Avoidance System) on the other

hand provides Resolution Advisories directly to the pilotsconcerned when the risk of collision becomes imminent.

Documents

Onair Issue 21