Trajectory prediction

On 6 September 2019 an aircraft almost took off from a taxiway instead of the Zwanenburg Runway. The ISMS partners jointly analysed this incident and a task force was formed to formulate measures to reduce the risks of take-offs from taxiways in the dark. A number of these measures were immediately implemented. For example, the standard night taxi route has been changed and the location has been identified as a hotspot where pilots and air traffic controllers are required to be extra alert. The markings that guide pilots towards the runway have also been made clearer. The task force is working out further structural measures.

Schiphol and its partners are exploring navigation and surveillance systems in vehicles on airside, to reduce the likelihood of runway incursions.

Schiphol and its partners are revising the names of specific taxiways. We will implement a revised nomenclature of the taxiway system to improve consistency. This will reduce the likelihood of errors and misunderstandings due to similar/confused naming conventions.

ISMS partners have investigated the reasons why ground personnel on platforms and service roads do not always comply with the rules and regulations. This research demonstrates several factors at play. To improve this situation, we have now implemented measures that were feasible at short notice. For example, all vehicles on airside have been equipped with seatbelts and handsfree communication devices. We have also introduced stricter airside access rules. The longer term safety improvements are currently being worked out and implemented.

A missed approach is considered a standard procedure. An aircraft can come into conflict with departing air traffic when it has to execute a missed approach and a converging departure runway is being used. Air Traffic Control the Netherlands (LVNL) and its partners have been investigating how they can further increase the safety of this procedure.
Timing appears to be an effective measure to reduce the risk of converging approach and takeoff operations. By ensuring there is adequate time between these operations we can further decrease the risk of conflicts occurring. This is being worked out further for implementation.

Air Traffic Control the Netherlands (LVNL) and its ISMS partners will improve the planning systems to increase predictability of flight profiles to reduce collision risk as part of the European SESAR (Single European Sky ATM research) programme.

The European Union is improving the use of European airspace under the project name ‘Single European Sky ATM Research’, or ‘SESAR’. As part of this project, approaches based on satellite technology (RNAV) are currently being implemented at Schiphol. This allows aircraft to carry out an RNP Approach which involves using three-dimensional GPS navigation on the approach to a runway. As of 7 November 2019, an RNAV approach is possible for four runways at Schiphol. The navigation technology makes flight paths for approaching aircraft more predictable, which will reduce the likelihood of any in-flight safety incidents.

The Ministry of Infrastructure and Water Management, Air Traffic Control the Netherlands (LVNL) and other partners are investigating improved ways for inbound traffic to enter the airspace around Schiphol as part of the airspace restructuring programme. This would be a next step in developing the operational concept. Doing so would increase the predictability of flight profiles in approaching aircraft to evenly spread traffic load, which would reduce the likelihood of occurrences that affect flight safety.

Schiphol and Air Traffic Control the Netherlands (LVNL) are implementing ‘Follow the Greens’. These are a set of sequenced green lights that guides pilots along the assigned taxi route. This visual aid eliminates the need for pilots to consult maps, reduces workload for ground controllers and relieves stress on ground frequencies. It will improve coordination and reduces the likelihood of on-ground safety occurrences and runway incursions.

Schiphol and its partners are exploring the introduction of Runway Status Lights (RWSL). These are series of autonomously-operating red in-pavement lights that warn both pilots and vehicle drivers for other aircraft or vehicles on runways. This visual aid will reduce the likelihood of runway incursions.

Links:

• RWSL implementation in Paris-Charles de Gaulle

Schiphol is building a new pier which will have 8 gates for both wide and narrow-body aircraft. The A-pier is situated in the South-West area of the airport, next to runway 06/24 (Kaagbaan). The new pier will increase gate capacity and relieve gate allocation constraints, reducing the likelihood of on-ground safety occurrences.

Schiphol is equipped with a circumferential double-lane taxiway system, except for the current Quebec taxiway. Schiphol and its partners will increase operational predictability, uniformity and ground capacity by doubling the Quebec taxiway. This will reduce the likelihood of on-ground safety occurrences. The double taxiway will be integrated in the clockwise and counter-clockwise routing of the Alpha and Bravo taxiways. The duplication of the Quebec taxiway will be implemented in three phases (1A, 1B and 2). Phase 1A is currently being implemented, phase 1B is in the planning stage. These phases realize the duplication of the taxiway system.

Opposite traffic in SW corner – with (right) and without (left) dual taxiway Q

Congestion in SW corner – With (right) and without (left) dual taxiway Q

Schiphol and its partners are conducting a study on the possibility for ground handlers to share their vehicles and equipment. Sharing reduces the movements and the amount of ground handling equipment at aprons, such as stairs and baggage carts, and less material is left on the platforms. This situation reduces the likelihood of safety occurrences on the ground.

Air Traffic Control the Netherlands (LVNL) and Schiphol consider moving towing movement control to the operation room in the Tower as ground control in order to enhance communication and coordination. This will reduce the likelihood of safety occurrences on the ground.

Runway combination changes that take place at the last minute may cause a disruption to the expected flight handling process, both for pilots and air traffic controllers. Air Traffic Control the Netherlands (LVNL) and Schiphol have developed measures to further reduce the number of last-minute runway changes, and the associated risks, in order to prevent air and ground safety incidents. For instance, we maintain landing runways when an aircraft is in the Terminal Manoeuvring Area (TMA) Schiphol; in addition, we use two departure runways when needed for a more stable traffic flow. We have also developed measures to improve the predictability of runway use and traffic flows using improved planning systems such as Arrival Management and Collaborative Decision Making. The percentage of last-minute runway combination changes is being monitored closely.

Aircraft following the routing to the beginning of runway 18L (Aalsmeerbaan) pass intersection N2/E6. At that point, the traffic crosses runway 09 (Buitenveldertbaan).

Schiphol and its partners are creating a runway stop bar in order to prevent aircraft that erroneously turn right from taxiing via the Buitenveldertbaan runway towards departing traffic. This will reduce the risk of runway incursions.

When taxiing to or from the Sierra platform, aircraft cross runway 06/24 (Kaagbaan). Schiphol and its partners have researched the ways that this crossing can be made safer to mitigate the risk of possible runway incursions. We also looked at alternative taxi routes to and from the Sierra platform. After research it is decided that aircraft are going to use a new intersection at Sierra 1. Because aircraft do no longer cross at a ‘high energy point’, the risk of runway crossings will decrease.

ISMS partners jointly investigated a safety incident in 2018, which happened between a towed aircraft and a marshaller in the field. As a result, Schiphol and its partners have already taken a number of further measures, such as tightening up the procedure, to reduce the risks of marshalled towing. We have also reduced the need to marshal towing movements, thus reducing the risk of safety incidents with marshalled tows.

ISMS partners jointly investigated a runway incursion in which an aircraft was cleared to enter the Zwanenburgbaan (Runway 18C), while another aircraft had permission to depart to the south. The study brought a number of measures to light which may further reduce the risk of incorrect line-ups. For example, the sight lines from the Control Tower may be improved. We have also conducted further research into the ways of working and operational procedures when taking-off from the Zwanenburgbaan Runway (18C). The measures are being worked out further and are being implemented.

Two aircraft made contact with each other on two separate occasions, 15 February 2019 and 9 July 2019, during a pushback manoeuvre. The ISMS partners investigated the accidents. We have set up a task force to develop any possible measures to prevent this type of accident in the future. The task force has implemented two measures to prevent pushback accidents in the future by changing the long pushback procedure and the responsibilities of the ground controllers and the pushback drivers. The specific pushback risks have been brought to the attention of the drivers and controllers and we are currently developing and implementing additional measures.