Impact of RECAT-EU on the departure capacity at Schiphol Airport
Abstract: EUROCONTROL has developed a re-categorization of the wake turbulence categories as defined by ICAO. The initiative splits the “Heavy” and “Medium” categories into “upper” and “lower”. This results in new longitudinal separation minima for traffic. The new categories yield lower separation minima for certain traffic combinations. This can potentially benefit runway throughput, while still maintaining acceptable safety levels. Implementing the new wake turbulence categories are expected to lower the separation minima for certain traffic combinations. It is expected that Schiphol airport will see a runway throughput increase, as the traffic combinations are expected to be positively affected by the new separation minima.
Optimising Preferred Use of Schiphol runways
through flexible ILS maintenance (OPUS)
Abstract: In order to minimise the impact of the ILS measurements on the capacity of busy Schiphol Airport, LVNL and NLR have since 2006 carried out a number of projects aiming to reduce the number of ILS flight tests without compromising safety (see references , , , ). In these projects, NLR performed the analysis and justification of LVNL’s conjecture on predicting (up to certain accuracy) specific ILS flight tests by ground measurements. The results allowed LVNL to reduce the total number of ILS flight test runs at Schiphol from 29 to 3, that is, by about 90%. This reduction of inspection flights contributed to the abatement of noise by measurement flights as well. Consequently, the ILS ground measurements then became the dominant factor in runway occupancy time. The project “Business case – Optimising Preferred Use of Schiphol runways through flexible ILS maintenance”, for brevity referred to as “OPUS”, aimed to assess the feasibility of additional permanent ILS signal quality monitoring, enabling a more flexible planning of ILS ground inspections at Schiphol. This document is the final report of OPUS. It contains an overview of the project’s theoretical and practical approach, the expected results and limitations, the actual results, and finally conclusions and recommendations. It should be noted that the project was a feasibility study including some safety case aspects, yet a complete design and safety assessment were out of scope.
Initial Target Time Over/Arrival Concept for
Amsterdam Airport Schiphol
Abstract: One of the major sources of delay at Schiphol is the occurrence of so called hotspots. An example of such hotspot is the occurrence of a bunch of traffic particularly at the boundary of the Amsterdam FIR. A hotspot occurs as a result of a situation where traffic demand is higher that capacity. These hotspots reduce planning flexibility, and complicate capacity forecasts for flow management ATCOs and creates an imbalance between demand and capacity. TTO/TTA can aid in the resolution of this imbalance. To combat hotspots, and balance demand with capacity, ANSPs request the Network Manager (NM) in Brussels to regulate traffic by imposing delays on aircraft take-off times. These take-off delays result in new Calculated Take-Off Times (CTOTs) for aircraft. CTOTs should, in principle, alleviate hotspot, and therefore, reduce the need for path stretching actions from ATCOs. For Schiphol, the period in which the expected demand exceeds the available capacity, a request to the NM is sent to issue CTOTs. Practice has shown, however, that CTOTs do not have the full desired effect because flight crews aim to recover any CTOT imposed delays by flying faster and/or by requesting different routes (horizontally and vertically). In other words, hotspots continue to occur in spite of CTOTs. To improve the effectiveness of CTOTs the Target Time Over/Arrival (TTO/TTA) concept is a potentially effective measure. This study details the TTA concept, analyses best-practises of past-trials at other airports and uses these best-practises to sketch an initial TTA concept for the Schiphol operation which can be used in a first trial. The TTA concept fits the long term LVNL objective to move towards a more collaborative airport operation between ANSP and airline.
Holding Support for Area Control
Abstract: The operational concept in the Dutch Airspace does not include the use of holding patterns in nominal situations. Instead, vectoring is used to create the optimal approach sequence. Holding is only used during non-nominal conditions, because significant delays may need to be given to inbound flights under such conditions. Nevertheless, holding operations happen regularly at Schiphol, for example due to stormy conditions or low visibility. Although the current holding procedures at Schiphol are safe, they are not always optimal. Therefore, improvements for holding operations may be possible that improve overall performance and predictability. One of the findings of current holding operations is the unpredictability of the duration of holding orbits. Turns sometimes take well above the expected 60 seconds, up to 100 seconds in the worst-case scenario. This report provides a list of solutions based on two solution categories: Ground-based solutions and Airborne solutions. These individual solutions are evaluated and combined in four high-level concepts.
Continuous Climb and High Altitude SIDs
Abstract: Keeping all traffic laterally combined on a single SID is likely to cause a drop in capacity of 4-7 movements per hour. Imposing a speed restriction of 230-250 knots starting at 3000ft provides a capacity gain of 2
movements per hour since aircraft can be sequenced more closely. ADS-B data shows 95% of the operation can operate at these restrictions. Tighter speed restrictions only provide marginal improvements and lower compliance in the operation. The effect of a speed restriction is limited since most spacing differences occur in the first 2000ft and the speed profile is not always the critical factor in separation. Analysis of vertical profiles shows that 95% of the aircraft operating at Schiphol can fly a fixed angle of 8%. Using this angle, aircraft would perform a conventional NADP-2 departure until 2000ft, followed by a climb with a fixed angle to 6000ft located 12.3nm from the runway. Noise modelling shows that this new profile causes the noise footprint to narrow along the SID, due to a lower power setting. At the same time the noise footprint increases in length along the extension of the runway since aircraft fly at a lower altitude for a longer time.
Abstract: Dutch airports have grown considerably over time. This growth takes place almost autonomously. No mechanisms are established to balance this growth among airports, routes or airspace strategically. It is assumed that, without profound reformation, the maximum airspace capacity will soon be reached. The Ministry of Infrastructure and Water Management has initiated the Dutch Airspace Redesign Programme’(DARP) or Programma Luchtruimherziening to reform the Dutch airspace. In this programme
there are various ongoing policy activities. The Knowledge Development Centre (KDC) performs research in support of some of these activities.
In the policy development, the relationship between Schiphol Airport and regional airports is examined closely. Presumably further independent growth of these airports will lead to bottlenecks in the Dutch airspace. Although the DARP aims to address these bottlenecks, the Ministry and KDC also want to
carefully consider the ways air traffic can be better handled by jointly managing air traffic. Managing air traffic into multiple, nearby airports is regarded as a multi-airport environment.