Memorandum by National Air Traffic Services
Ltd (NATS 02)
1.1 The Sub-Committee is to conduct a further
inquiry into recent developments in National Air Traffic Services
Limited (NATS), and has requested information on:
progress on the New En-Route Centre
progress on the New Scottish Centre
project and the current position on the replacement of the Oceanic
Flight Data Processing System; and
recent computer problems at West
2. PROGRESS ON
2.1 Following detailed re-planning of the
project during 1998, the Committee was advised in October 1998
that Swanwick was expected to begin operational services in Winter
2001/02. The Defence Evaluation and Research Agency (DERA) confirmed
in their report to Government in November 1998 that a Winter 2001/02
target date was feasible in their view. Subsequently, the NATS
Board approved a detailed Plan to Completion for the project in
2.2 The project continues to achieve the
major milestones set in February 1999, and remains on track to
achieve the Winter 2001/02 target. The date on which operations
will start at Swanwick was confirmed at the July meeting of the
NATS Board as 27 January 2002. The Chairman and Chief Executive
of NATS subsequently briefed staff at West Drayton on 12 July.
2.3 The next major milestone in the programme
is Technical Handover (TH), which is scheduled for 20 December
2000. TH represents the point of final hand-over of the system
from the project manager to the operations manager. The Centre
is certified to be fully operationally capable and is permanently
connected to the ATC infrastructure. Following TH, the main focus
of activity moves to ATC conversion training on the new system.
This activity starts in January 2001, leading to the start of
operational services in January 2002.
|1||Full Technical Transfer (TT7)
||Mar 99||Mar 99 (c)
|2||Start of Large Scale Simulations Phase 1
||Mar 99||Mar 99 (c)
|3||Complete Large Scale Simulations Phase 1
||Jun 99||May 99 (c)
|4||Commence Baseline Interface Test (Non FDP) Run For Record
||Aug 99||Aug 99 (c)
|5||Commence Baseline Interface Tests (FDP) Run For Records
||Dec 99||Feb 00 (c)
|6a||Commence Large Scale Simulations Phase 2
||Nov 99||Nov 99 (c)
|6b||Complete NAS 2609 Development
||Mar 00||Mar 00 (c)
|7||Complete Large Scale Simulations Phase 2
||May 00||May 00 (c)
|8||Baseline Combined System Testing Run For Records Complete
||Aug 00||Aug 00 (c)
|9||Incremental Operational Verification 1 Complete
||Aug 00||Aug 00 (c)
|10||Incremental Operational Verification 2 Complete*
||Sep 00||Nov 00 (f)
|11||Incremental Operational Verification 3 Complete*
||Oct 00||Dec 00 (f)
||Oct 00||Dec 00 (f)
|13||Operational Readiness Demonstration Complete
||Dec 00||Mar 01 (f)
|14||Commence ATC Conversion Training
||Jan 01||Jan 01 (f)
|15||Transfer Of En Route Operation to Swanwick
||Nov 01||Jan 02 (f)
* IOV2 and 3 are deferred to November and December respectively
to improve the overall robustness of the test programme.
2.4 In addition to confirming the feasibility of the
Winter 2001-02 timetable, the DERA Report made a number of observations
and recommendations on the key risk areas within the project.
DERA noted that, from a technical viewpoint, the main concern
was the backlog of outstanding software changes. DERA also noted
that establishing controller confidence in the system and an effective
process of communication within the Company would be vital to
the success of the project. Given the scale of the tasks remaining
at the end of 1998, DERA were clear that achievement of the Winter
2001-02 target would require firm project management.
2.5 These areas have all been addressed in depth by NATS.
The key risk areas within the project continue to be closely monitored
by the NATS Board. Major changes have been made in project management
arrangements within the Company both in respect of the project
and, more generally, in preparation for implementing the NATS
Long Term Investment Plan. The services of independent experts
have been retained to provide advice to the Board both on the
Swanwick project and other aspects of project management and software
design. In addition, Bechtel are now supporting NATS on the implementation
of the project programme.
2.6 As with any large complex project, there are risks
to the overall schedule. The major area of risk within the project
continues to be the delivery of a stable software system which
is fit for purpose. This includes the incorporation of system
changes, elimination of system faults (known as Programme Trouble
Reports or PTRs), and alignment of the Swanwick system with the
National Airspace System (NAS) at West Drayton.
2.7 Change request (CR) status: Three software
builds are planned for deployment prior to the start of operational
services. Build 1.37 has now been delivered and is in the test
phase. Testing on Build 1.37 indicates that the software is of
high quality and robust. Build 1.38 is packaged and work is progressing
on the definition of the CRs for Build 1.39. The content of Build
1.39 will be agreed and committed to software development by mid-October.
2.8 PTR status: The PTR situation is continuing
to improve, with necessary reductions in PTR numbers looking achievable
for both TH and for the start of operational services. It is not
realistic to expect that the number of PTRs can be reduced to
zero; the aim is to eliminate all PTRs that might affect the quality
of the operational service in any significant way.
2.9 NAS update: Changes are required in NAS
to support Swanwick in operational service. NAS Version 26.09
is targeted for operational service in November this year. Software
development is complete and 26.09 is in its test phase. The last
formal build of NAS before Swanwick enters operational service
will be Version 26.10. Version 26.10 is due to enter service in
2.10 Controller availability: A key requirement
is to have sufficient validated controllers in place for the start
of operational services at Swanwick in January 2002. Manpower
projections indicate that the supply of controllers will be sufficient
to meet operational requirements. The conversion training roster
for all LATCC Area Control staff has now been published, including
over 21,000 individual allocations of staff to activities.
2.11 Controller acceptance: Controller acceptance
is a critical requirement in achieving the successful introduction
of the system into service. Following completion of the programme
of simulations, there is now general acceptance within the controller
community that the system is viable.
2.12 Swanwick costs have been contained within budget
during the past two years and continue to remain in line with
the £623 million estimated cost to completion identified
in the report by Arthur D Little. Project costs are approved on
an annual basis, with the capital element being subject to DETR
and HM Treasury approval. Costs in the period to 31 March 2000
were as follows.
|Programme management, associated costs and internal costs capitalised
2.13 The budget for the year to 31 March 2001 is £34.7
million (capital £10.2 million and revenue £24.5 million)
in respect of contracts between Lockheed Martin, Frequentis, Logica
and NATS, inclusive of capitalised internal labour. Forecast costs
for the current year remain in line with the approved budget.
3. PROGRESS ON
3.1 Proposals for the New Scottish Centre (NSC) were
first submitted to Government in 1992 and EFL cover was provided
for the project. Subsequently in the 1993 Budget statement, the
Government announced that the project would be financed under
the Private Finance Initiative (PFI) and EFL cover was withdrawn.
Throughout the period from 1993 NATS worked closely with departmental
and Treasury officials to try to make a success of the PFI initiative
while continuing to make the point, first in private and from
1994 in public, that PFI was not the right way forward. The NSC
PFI was finally abandoned in 1999.
3.2 Work on the NSC is now progressing well. Following
termination of the PFI contract with Sky Solutions, a new Master
Agreement was negotiated with Lockheed Martin for the systems
element of the project and this was signed in February this year.
The building design element of the project has been re-tendered.
The project is now proceeding on the basis of conventional funding.
The new Centre is currently targeted to enter operational service
in the winter of 2007-08, subject to the outcome of detailed planning
and the letting of contracts. NATS and the DETR jointly appointed
Bechtel in June 1999 to manage the NSC project.
3.3 The building: Work on the design of the
NSC building is in progress. Two firms are competing during the
first 120 days of the building "outline" design phase,
covering such matters as site layout, building shape, mechanical
and electrical systems and landscaping. One of the firms will
be selected in December this year to complete the detailed design.
Construction is due to begin on site in the first quarter of 2001.
3.4 The systems: The NSC will benefit from
the use of the software already developed for NERC. Under the
Master Agreement, components of the project will be separated
into individual contract line items each of which will be subject
to negotiation. The contract line items already agreed cover the
definition and development of the new platform for NSC to operate
the Swanwick software, and the baselining of the essential changes
necessary for Scottish operations.
4. REPLACEMENT OCEANIC
4.1 The FDPS2 project was designed as a replacement for
the existing Oceanic flight data processing system based at Prestwick.
Its objective was to provide improved system reliability and functionality,
enabling the implementation of ICAO satellite based concepts for
the management of air traffic over the North Atlantic. The project
was let as a PFI contract in 1997.
4.2 Following the Critical Design Review (CDR2) milestone
at the end of May this year, NATS has taken steps to terminate
the contract with EDS. CDR2 was a contractual milestone at which
point the contractor was required to demonstrate that its designs
met NATS' requirements. The NATS Board has yet to decide on the
best alternative procurement strategy, however the outline plan
is to procure a "core" FDP product off-the-shelf to
provide a minimum requirement FDP replacement system for 2004.
Thereafter, NATS will develop added value functionality as and
when there is a business need for it.
4.3 The timescale for implementing a replacement Oceanic
FDPS system has been extended as a result of decisions by ICAO.
In particular, satellite based procedures will not be required
before 2005 as the airlines need to equip their aircraft with
the necessary equipment to enable new separation standards to
be introduced. There has also been a marked improvement in the
reliability of the current system. These two factors, and planned
capacity improvement, will allow the existing system to meet forecast
demand at least until 2006.
5. COMPUTER FAILURES
5.1 There have been four failures of the National Airspace
System (NAS) this year at West Drayton. The failure that occurred
on 17 June resulted in substantial air traffic delays. Two less
serious failures occurred in June and another in August. The failures
were caused by unrelated software design faults.
5.2 By way of background, aircraft are required to file
a flight plan before departure. NAS stores these flight plans
and produces flight progress strips, which controllers then use
to control aircraft movements. In the event of a major system
failure, safety must be assured and controllers are trained to
revert to manual methods of operation, which require flight strips
to be written by hand. This slows the throughput of traffic and
hence can result in significant delays, but the safety of the
system remains uncompromised. When the failure occurred on 17
June NATS controllers, support staff, engineers and managers performed
outstandingly, keeping disruption to a minimum consistent with
maintaining high safety standards. Their actions were commended
in Parliament by DETR Minister, Nick Raynsford, who said, "While
I very much regret the failure, NATS staff did a first-rate job
in responding to difficult circumstances when the software failed.
They put in place standby arrangements to ensure that safety was
paramount at all times which must be the main consideration."
5.3 The NAS system was originally procured in 1974 but
has been upgraded on a number of occasions. The computer hardware
was replaced in 1989 and is due to be replaced again within the
next 12 months. NAS has proved to be extremely reliable over the
years and, prior to these failures, had operated with availability
in excess of 99.9 per cent throughout the 1990s.
5.4 New versions of the NAS software are installed annually
and occasionally more frequently. In addition, adaptations are
made to the database and its configuration parameters on a monthly
basis tied in with the world-wide AIRAC cycle, to notify changes
in the airspace environment and aircraft routeings. Two days prior
to the failure on 17 June, new configuration parameters had been
installed on the system to improve flight strip printing for controllers
at Prestwick and this triggered a latent design fault in the software.
However the main reason for the extended delay in restoring full
service was the failure of linked communications systems and the
need to rebuild the data in these systems.
5.5 The causes of the failures were established within
a short time of each event and a combination of software fixes
and other preventative actions have been identified, tested and
implemented. Following the events on 17 June, new system design
constraints were introduced to prevent the failure of linked systems.
These were proven to be effective during the course of the failure
on 12 August when the system was recovered within an hour. Since
then there have been no failures. It is not possible to guarantee
that there will never be failures in a system as complex as NAS,
but the changes made since June have enhanced the resilience of
6.1 Over the past 12 months NATS has made good progress
in many areas:
the Swanwick project remains on track;
the New Scottish Centre project is now moving
new contracts for airport operations have been
won in open competition;
safety performance has been maintained, and average
delays remain at low levels despite the continuing increase in
charges to users have again been reduced; and
preparations for the Public Private Partnership
6.2 NATS continues to seek further improvements in the
safety, quality and cost of its operational services and the delivery
of the project programme. This has been a busy, and generally
very successful, year for the Company and it is appropriate, in
conclusion, to pay tribute to the competence, skills and dedication
displayed by staff throughout NATS in this period.
National Air Traffic Services
29 September 2000