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US SPECIAL REPORT: INTEROPERABILITY

When it comes to aviation officials airing

their dirty linen in public, there have

been few washdays that have produced

quite such a spectacular pile of soiled laundry as

the one this summer, writes Aimée Turner.The débacle was ignominiously splashed

across the Wall Street Journal detailing US avia-

tion officials’ fears over whether aircraft flying

between the US and Europe would be able to

use each other’s air traffic management systems

as progress in NextGen modernisation stateside

and its European counterpart SESAR gains pace.

The talk was of an impending breakdown in

relations between those charged with setting

standards in the field of data communica-

tions, something which risked undermining

an aviation partnership that has to date been

an example of perfect transatlantic unity - in

industrial terms at least.

Federal Aviation Administration (FAA) chief

Michael Huerta has gone on record as pledging

that economic uncertainties and challenges

will neither deter the two trading regions

from staying the course with their respective

modernisation efforts nor prevent them from

ensuring that interoperability remains at the

fore of those efforts.

That however contradicted a warning deliv-

ered by John Hickey, one of the FAA’s top safety

officials, that the US and Europe continue to

move in different directions and risk undermin-

ing progress on both sides of the Atlantic. He

told a US-European safety summit that he was

becoming ‘greatly concerned about divergent

paths’, including conflicting timetables and

technical standards over data communication

technologies. It was those comments that led to

the recent unsettling media attention.

Hickey said he feared that with different

timetables and requirements, full co-operation

and agreement on the choice of specific tech-

nologies would ultimately break down which in

turn would create a fractured global

satellite-based network offering no

prospect of seamless operations.

Hickey’s comments reflected internal

FAA concerns that a two-speed political and

economic deployment timetable risked setting

a precedent that would lead to even further rifts

and complications that could impact transforma-

tional technologies further down the schedule.

Gold StandardIt should have been all so different. A

2011 pact promoting the gold standard of

interoperability between the US and Europe

was underpinned by a formal collaborative

structure – principally through the workings

of joint standards development committees

made up of the membership of RTCA and

Eurocae standards bodies.

So what is at the heart of this summer’s very

public falling-out?

After three years of collaboration the US and Europe are fighting to stop conflicting technology agendas from damaging transatlantic partnerships

Exchange?Fair

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US SPECIAL REPORT: INTEROPERABILITY

Michael Standar, the SESAR strategy chief

heading international relations, says that the

two sides have since effected a rapproche-

ment and that the transatlantic spat was a

mere storm in a political teacup.

“This has been an issue for some time. We

needed to converge on a standard that we

could push forward through both Eurocae and

the RTCA which would fit the timescales of

both NextGen and SESAR,” says Standar. “That’s

been a discussion all along. The issue was more

about timing with the specific programmes.

It was our way of pushing and saying, look

we have a memorandum of cooperation with

the US, we are leading the two largest ATM

modernisation programmes in the world so we

need to come to an agreement.”

Standar’s colleague David Bowen, who heads

ATM operations and systems at SESAR, says that

because the issue over meeting deadlines was

not being necessarily handled with any sense

of urgency, a summit of FAA and SESAR experts

was convened in August.

“What we did at the outset was draw up a clear

statement of the needs from both the US and

European positions in terms of which datacomm

applications were critical for the two programmes

and what the timings were in terms of deploy-

ment,” says Bowen. “It was really the timeline that

was causing the issue as the Europeans are push-

ing for a nearer term initial deployment of some

of these critical applications.”

Bowen explains that the Europeans want to

adopt a more incremental approach

with an initial roll-out in

2018 for some

datalink capabilities with

a focus on 4D operations whereas the US wants

a later date but a more comprehensive roll-out.

“This was predicated on the publication

of the standards by 2014 at the latest which

would give industry the necessary time to start

the industrialisation for equipage in time for an

operational launch of 2018,” he says.

The US however adopted a different view,

determining that there were a few missing

elements in the set of applications SESAR

had been working towards over recent years,

highlighting three additional services it wanted

to feature as part of a package termed ATM

Baseline II.

An Airframer’s Perspective Mike Caflisch, Boeing

With few European companies in NextGen

and few American ones in SESAR, there

will be challenges in focusing on the in-

teroperability question. That is one of the

reasons why the roles played by Boeing

and Airbus are so important.

The US Federal Aviation Administration

(FAA) and Eurocontrol are attempting to co-

ordinate NextGen and SESAR efforts. ICAO

has an interest in promoting ‘One Sky’

through its Global Air Navigation Plan. 

There is a global priority to establish

interoperable airspace systems but the

unintended consequence of these multiple

efforts is similar to the hard part of what

Europe is trying to do with SESAR. 

Disparate global data systems, hardware,

infrastructure, processes and procedures

- combined with differences in state and

regional requirements and priorities - make

interoperability extremely challenging. 

Work is progressing on the establish-

ment of global standards but the interna-

tional community must be careful not to

limit or inhibit interoperable solutions. Ad-

vancements in technology and the ap-

plication of those technologies will help

to define the future of interoperability in

realistic and operationally-driven ways. 

Interoperability in avionics is assured

through ICAO, RTCA, EASA and other

standardisation committees but it doesn’t

always work perfectly. A recent example is

the different requirements for ADS-B Out

performance for different airspace regions.

However, it is a much better process

than interoperability in ATC procedures

and automation systems, where there

is basically no formal process for global

standardisation. Additionally, there is not

a process for ‘synchronising’ investments in

new systems and operations across ANSPs,

which does factor into interoperability as

experienced by the aircraft operator.

Disparate global data systems, hardware, infrastructure, processes and procedures combined with differences in state and regional priorities make interoperability

extremely challenging 

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US SPECIAL REPORT: INTEROPERABILITY

“As such they came to the RTCA/Eurocae fo-

rum with a proposal to delay the publication of

the standard of one to two years,” says Bowen.

This however posed a serious problem for the

Europeans because that delay would prevent

them achieving initial deployment by 2018.

A solution had to be found that would meet

Europe’s needs as well as satisfy the FAA’s desire

to include capabilities such as dynamic RNP,

advanced interval management and an ability

to transmit wind information back to ATC.

Standar here points out that Europe is not

against embracing these additional capabilities.

“The difficulty we had is that if we kept on put-

ting off setting the standards it would not be

until 2023 that we had anything to work on. It

was important for us to get something in place

and build on the deployment experience we

gain from validation.”

Bowen agrees saying that all standards evolve

over time but that there has to be a balance

between a stable stance that avoids the risk of

industry and airlines having to reinvest

while allowing evolution and new capability.

At OddsIn addition to conflicting timescales, the way in

which both regions want to use datacomm is

also at odds.

“The business case element of datacomm

which for the Europeans is pretty much based

on 4D trajectory management is not so pivotal

for the US,” says Bowen. “The US has a very

strong view in terms of the use of PBN and RNP

etc and their core focus is on datacomm ena-

bling those elements to be used more widely.”

“We have certainly nothing against that,”

points out Bowen. “It’s just that our focus on 4D

essentially allows increased predictability and

less reactive management. I wouldn’t necessar-

ily say any one is better than another, it’s just

another perspective.”

The solution has been to establish a set of

services which meet both European and US

needs. Here, Bowen says it doesn’t make sense

to go through a whole standardisation indus-

trial and deployment cycle for just one single

capability. “It makes sense to package them

into a set of things some of which will be used

in some places, some of which will be in others

and some of which are used everywhere. The

key is to make sure you have common equipage

to avoid multiple investments.”

The solution will be embodied in a new co-

ordination plan agreed between SESAR and the

FAA which enshrines a two-step approach to

capabilities. An initial version of the standards

to be applied will be published in early 2014 as

per the original schedule which will meet the

initial needs of the Europeans. That will allow

industrialisation of a product by 2018 in which

initial 4D capabilities will feature.

The additional US capabilities will continue

to be worked on within the Eurocae/RTCA

forum which aims to publish a final standard

that ensures these are compatible with the

initial version sometime in the mid to late

2015 timeframe.

Bowen says industry has been deeply involved

during the whole process and that the airframers

Boeing and Airbus have this summer drawn up a

joint position paper which provided an excellent

catalyst to agreeing the two-step approach.

Michael Standar insists that the beauty of

the collaborative result achieved is in recognis-

ing that a one-size approach is not appropri-

ate or useful. “They might have their system,

we may have ours. The important thing is that

they have to be interoperable. What we can

show is that we can achieve interoperability

for seamless operations without having an

identical system.”

US Survey 2013 Are interoperable airspace systems feasible?

Carol Huegel Metron AviationInteroperability has long been focused on the aircraft

and associated procedures. Looking forward, it will be

equally important to address the interoperability needs

with respect to data exchange. Accurate, timely exchange of operational

data among all stakeholders will be pivotal to the success of all moderni-

sation programmes. While there are many industry professionals who

understand the technical elements of the various data exchange models,

a significant focus on the processes, procedures and policies associated

with transparent data exchange is a must. 

Bobby Sturgell Rockwell CollinsInteroperability has been a key theme between NextGen and SESAR for sev-

eral years and ICAO is working hard to keep the need for interoperability in

front of everyone. What has caused things to flare up recently is perhaps the

somewhat divergence on data link programmes between the US and EU.

Hopefully, that can get resolved over the next couple of years. You are never

going to get perfect coordination between NextGen and SESAR, especially

with respect to mandates and timelines. But you do want interoperability in

the end and all ANSPs should be striving to ensure that happens. The worst

thing you can do for your customers - the operators - is to impose additional

equipage requirements to perform similar types of operations.  

Mike Caflisch BoeingThe key difference between FAA and SESAR is in their solution selection,

such as SESAR’s emphasis on i4D using aircraft RTA capabilities versus the

FAA’s emphasis on ADS-B In for Interval Management. This can lead to

a global harmonisation problem for aircraft operators and manufactur-

ers, i.e. multiple solutions for the same operational problem in the same

timeframe. For global interoperability to have priority, the airplane manu-

facturers, backed by their customer airlines, must continue to make the

economic arguments concerning the cost to the aircraft and to the airlines

should diverse systems be adopted in different regions of the world.

Roberta Leftwich Booz AllenDoes every nation, regardless of traffic density or airspace characteristics,

need to have technology and procedures that are truly of the same level

as the rest of the world? CANSO’s Guide to Seamless Airspace lays out

one sound approach in which certain airspace characteristics need to be

globally or regionally standardised (e.g., phraseology, nav performance

requirements), some harmonised (e.g., flight level allocation schemes),

and some truly interoperable.

Read more views on the challenge of interoperability at www.airtrafficmanagement.net/ussurvey2013