Technical Liability in Satellite
Navigation
Kim O'Neil
Advanced
Aviation Technology Ltd.
October 2000
Abstract
In the development of Global Navigation Satellite
Systems (GNSS), liability is an issue that is often raised. Yet there is still
no satisfactory solution to this problem. Confusion seems set to remain for
some considerable time. This confusion is visible even in regulatory agencies
who seem unclear about the status of GPS but accept the partial certification
of GPS products and related services. Yet GPS is in use in Civil Aviation today
and aircraft are being supplied with GPS installed and certified to "near CAT
I" levels. However, the use of GPS in Public Transport Operations still raises
concern - largely because of the potential consequences of a GPS failure.
Despite this, liability still appears relatively low on the agenda, since it is
widely assumed that these issues will be resolved when 'appropriate'
institutional arrangements are put in place by ICAO. Yet, whether this is a
realistic expectation seems very unclear.
This paper is a preliminary discussion on some of the
issues that directly or indirectly affects technical liability in satellite
navigation.
1. Introduction
GNSS raises technical, commercial, political,
military, institutional and legal issues.
Issues such as liability, certification etc. are not
just purely altruistic considerations. There are many factors that must be
taken into account in order to navigate through the potential minefield that
lays in the path of user airlines, airports, ATM providers, manufacturers and
individual States as they make strategic decisions that will affect their
businesses a generation hence. There are many pragmatic considerations that
must be taken into account to ensure that correct decisions are made. This
paper attempts to discuss a few of them:
GNSS is not a system designed solely or specifically
for Civil Aviation. GNSS has many wide ranging applications across all industry
sectors and its applications are not just limited to navigation. Indeed, no
Civil Aviation Authority or group of CAAs could muster even a tiny fraction of
the resources that are required to launch a GNSS. The list of applications and
the value of these applications is so great, that the civil aviation market is
actually small by comparison - but still very large. This is one of the keys to
the problem: GNSS is a generic service of huge commercial significance.
- GNSS - means that fundamental navigation
services are not provided by CAAs.
2. Control of GNSS
It is perhaps not surprising that the US sees no need
for any other system than GPS. Despite the concerns of some States that control
of GPS by the DoD is simply unacceptable - even after assurances made by the US
President. Indeed, some see GPS as a military threat. Others see GPS as a major
commercial threat - even if currently free of charge (or perhaps because it is
free!). Some are simply uneasy that a single satellite navigation system
represents too great a risk of a common mode failure.
Without any doubt, the US stands to gain many benefits
if GPS is adopted as the sole satellite navigation system - and, of course,
knows it. Many of these benefits translate into straightforward commercial
advantage in the development of an enormous range of navigation products. Yet a
sole means system controlled by the US raises serious concerns.
- GNSS raises many issues of vested interest.
Europe is clearly so concerned that it is preparing to
launch its own system - in the face of considerable US opposition. This concern
prompted the EC to state that:
"…... If Europe does not act promptly, then
control of the entire system will be done from overseas.....User Requirements,
Standards and Certification Schemes will be set by those who own and operate
the system. The result will be a major dependence of Europe on the provision of
a strategic asset for the future and a poor perspective for European industry
to capture the huge associated market...".
Whilst launching such a system should be relatively
(and technically) achievable, some of the institutional and even the
administrative barriers may prove difficult to jump. It may also severely test
the ability of European States to work co-operatively together - although the
current political environment looks more favourable for this than it ever has.
However, paying for and maintaining the system will pose interesting
challenges.
- Competing GNSS systems may emerge - perhaps to
serve different markets….
What may test Europe even more than launching its own
GNSS, will be its ability to capitalize on this investment - and this is not
just a financial issue.
3. The Role of ICAO
ICAO generally requires its members to accept the
certification given by other States to its own navigation services and that
ICAO members accept the certification given by a member State to its registered
aircraft and licensed crew.
3.1 ICAO Standards
ICAO is busy setting standards both for GNSS and GNSS
based services. These standards naturally assume a GPS like service. Thus ICAO
is essentially 'retro-fitting' standards to an existing service (and assuming
some upgrading of those services). As the US is strongly represented in those
committees, it would be surprising to see anything in an ICAO Standard and
Recommended Practice (SARP) that wasn't compatible with GPS or an enhanced GPS
(which serves to illustrate the power of being first). Strictly speaking,
ICAO's role is simply to set safety and interoperability standards. However,
ICAO Panels occasionally overstep this mark and drift into specific design.
ICAO's actual role in GNSS standardization is a little
anomalous, as it appears to be taking a lead (in defining standards) when many
other sectors have a possibly greater interest. This is, in part, based on the
assumption that aviation is the most demanding user in safety.
- ICAO Standards will largely reflect existing
systems (i.e. GPS)
3.2 ICAO and the Status of GNSS
Indeed, many have assumed that GNSS would somehow be
'approved' by ICAO. Yet this UN Institution has no power or precedent for
giving any approval that would be legally effective. ICAO is more a forum for
agreeing common standards and settling relations on civil aviation matters
between its members. It is not an Agency with any delegated power to carry out
approvals. These are the sovereign responsibility of the member States. The
current ICAO institutional framework was put in place at a time when few could
have envisioned a global navigation system controlled by a single State.
ICAO has a Legal and Institutional Committee studying
the implications of GNSS. However, whatever the results of these investigations
are, they are unlikely to lead to any significant change in role for ICAO or
its constitution - as this would require the agreement of all its members. Any
solution found in ICAO for GNSS would be limited to civil aviation and would
not cover other forms of transport or other GNSS applications. This means that
a solution to the acceptance and 'certification' of GNSS would be more likely
found within a separate Convention between States for GNSS.
Realistically, ICAO will concentrate on the:
- Interoperability of GNSS (to prevent divergent
satellite navigation systems).
- The safety of augmentation systems (provided by
civil aviation)
Note that:
- ICAO will not be an investor or operator of a
future GNSS.
- There is no reason why GNSS cannot be a private
and commercial service.
- Some levels of GNSS service may be free, others
may be charged for.
- Competing GNSS providers must negotiate spectrum
from ITU.
4. Possible US Approaches to Certification
The US is a very large and monolithic market. Another
advantage it has, is its dominance of the Regulatory System (in ICAO, ITU
etc.), where it recognizes the benefits that can be obtained. US confidence in
its 'market pull' is great enough for it to 'go it alone' when it sees an
opportunity.
The approval of GPS by the US government for Civil
Aviation and Certification by its Agencies, would provide a comparatively
simple path for the introduction of satellite navigation services, products and
applications on US registered aircraft. Certification of the system may pose
interesting challenges, but it is still, a largely internal US domestic matter.
Translating this into International acceptance is not an insurmountable
challenge.
Indeed, it may be that the US simply declares GPS
ready for Civil Aviation use and publishes key performance parameters for use
in the certification of applications. A mountain of material on the
certification process will probably accompany this declaration. The US only
requires a consistent internal legal framework for GPS - for itself.
Reciprocal agreements with other States would provide
easy access for GPS products and services to other markets. Whether those
States would demand proof of the 'safety' of GPS is a moot point - it is
unlikely that the US will offer detailed system wide evidence of certification,
as this could be regarded a commercial (and military) secret. Audits by non-US
bodies are equally inconceivable and could never be deep or technically
convincing. GPS will simply be offered - "as is".
- There may be little to discover about liability
issues by studying GPS
Present FAA policy is to develop the Wide Area
Augmentation System (WAAS) in order to increase the precision and integrity of
the GPS service for aviation. This is closer to conventional provision of
navigation services (though not entirely so), since it will be a navigation
service offered by the FAA to aviation and certified for operational use within
its borders. Although a regional service, the region is continental USA (with
some overlap) i.e. a service provided to a single State. Other States on the
American continent will have to enter into agreement with the US for WAAS
services - if they wish to be formal beneficiaries of WAAS services. This will
probably involve a waiver of liability. Otherwise, even if available in areas
outside the US, GPS will not be specifically "provided" as a navigation
service.
However, EGNOS is a regional service operating across
many States. It is, therefore, little different from global services such as
GNSS - from a certification perspective. It is not a navigation service offered
and guaranteed by a single State within its borders. At the very least,
elements of the service are supplied from other States.
- Wide Area Systems present similar problems
Certification/Liability.
5. Certification - A Problem for Europe?
Europe will have to certify its GNSS in a way
acceptable to its own individual member States - a quite different problem to
that faced in the US - since its member States do not hold a single legal,
technical or institutional view. This is virtually a consequence of geographic
and demographic factors. There is significant discord between its members on
Transport issues (EU members rarely hold a common line on aviation issues).
This will require a much more public process. Europe
will also see a much clearer 'moral imperative' to be open about the
certification of its GNSS, since there will be much less secrecy in its
development and control. Accountability will be a greater issue, since each
State will be dependent on the services of the others. Thus, it is in Europe
that issues such as liability will pose significant problems. There will be no
clean sweep equivalent of a US Congressional Bill approving GPS for Civil use.
- In Europe, Accountability will drive
certification.
Indeed, given the demographics of Europe and the need
for traceable certification processes, Europe will inevitably be driven towards
augmentation provided at a local level i.e. ground based augmentation for high
integrity safety services e.g. landing systems.
Key issues for a European GNSS include:
- Global Interoperability
- Resolution of Key Technical Questions
- Frequency Allocation and Radio Protection of
Services
- Development of European Standards ·
Certification of Equipment and Services
- Safety
Many of these technical issues require specific
leadership from key European interests. They are not simply technical matters
alone, as their resolution depends upon negotiation and agreement between
various institutions and the establishment of several new institutional
arrangements. One specific example is whether Europe is seeking a simple 'GPS
look-alike' service, with little technical difference to GPS or whether it
intends to offer services which may have substantial enhancements over GPS.
This will be seen as an issue of "Global Interoperability" with significant
technical and commercial implications. No wide and open public forum (of
political, technical and commercial interests) yet exists in Europe to even
debate such an issue. Europe will have to press its case in ICAO and ITU if it
chooses a different route to that of GPS.
6. Legal Issues
The development of a civil GNSS will require that an
International Treaty be established governing safety, certification, use,
liability and charging. Such a Treaty must necessarily be drafted in high-level
terms. However, it must state the criteria for the provision and withdrawal of
service and specify those purposes for which it may not be used and detail
those conditions for the withdrawal of the service e.g. in case of serious
failure. It would have to be based on established UN principles i.e. those of
equal and unbiased access. GPS might not meet these criteria in full.
6.1 Legal Liability
Legal liability has to be assured in some way, to
protect the interests of the civil community in the event of serious GNSS
failure e.g. in the case of death or injury. Conversely, steps would also have
to be taken to protect a civil GNSS provider from hostile legal measures
following a major accident or disaster linked to its services. Limitations on
liability would also have to be put in place to protect the GNSS provider from
'loss of service' litigation. Such measures are likely, given the frequency of
accidents and the difficulty of identifying their causes - as in the case of
the many Controlled Flight into Terrain (CFIT) accidents.
GPS liability is a most sensitive issue for the US.
They would certainly seek to negotiate a reciprocal arrangements (sometimes
referred to as a 'cross waiver') with a European GNSS. Such an arrangement
would mutually exclude each side from liability. This would probably favour GPS
(and leave no civil redress against GPS for Europeans), and would probably not
inspire confidence in a civil system.
7. Preliminary Conclusions
Legal arrangements will surely be made for GNSS in
order to limit or indemnify it against loss or interruptions in service. If an
accident were attributable to a GNSS failure, then this may lead to
modifications to GNSS or restrictions in its use. In order to provide the
necessary assurances required for GNSS operations, a certain level of service
will likely be 'guaranteed' by an International Convention and this service
level can then be bolstered by Augmentation Systems. ICAO will ensure
interoperability (to a degree) between GNSS services and specify safety
standards for augmentation systems for civil aviation applications.
Consequently, technical liability of GNSS will not be effectively traceable or
enforceable - rather, the emphasis will be on Augmentation Systems.
Certification will remain a State prerogative. |
