In order to demonstrate the synergy between Qualitative and Quantitative Assessment, an example is provided using fictitious airspace. This example covers the life-cycle of a small project and illustrates the indivisible relationship between Qualitative and Quantitative Assessment. Because the examples are fictitious, readers should not be surprised should they identify alternative solutions to those proposed.
2.2.1 SAMPLE QUALITATIVE ASSESSMENT
The figure (left) shows aREF SCENARIO: R 27Sample Reference
(Used as Base Case: R 27-RT for FTS/RTS) Scenario of a fictitious Terminal Airspace. At the centre is Sector SA with routes numbered 1-7. SA is surrounded by four sectors: SB, SC and SD. Airport A lies in SA, Airport C in SC and D in SD. The Operational Manager has asked the Terminal Airspace design team to investigate complaints of SA controllers concerning excessive workload in SA during peak hours, especially in the vicinity of the crossing point X (marked in orange, at left).
Figure 2 - 1: Sample Reference Scenario/Base Case
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Preliminary Qualitative Assessment
As per the process described in Part C, the Terminal Airspace design team first describes the Reference Scenario (i.e. sector SA as it is today) and then critically reviews this sector. To help them, the Terminal Airspace design team invites comments from air traffic controllers who normally manage Sector SA. During the critical review, it is confirmed that the crossing point X is perceived as the main problem area and the cause of unacceptably high workload during peak periods. (These ‘discussions’ are, in themselves, qualitative’).
Quantitative and Qualitative Assessment.
To further assess the problem, the Terminal Airspace design team uses a spreadsheet (or airspace modeller) to analyse traffic in SA. What is established is that SA handles 52 flights in a typical peak hour (see Graph 2 - 1), and that that 30 of these flights cross at X as – see Table below. (Note: 30/52 is quantitative).
Graph 2 - 1: Sample Traffic Distribution (Time)
No. of flights Route No. of flights Route
10 Route 1 [RNAV/STAR to A] 12 Route 2 [RNAV/SID from D]
10 Route 3 [RNAV/STAR to C] 5 Route 4 [RNAV/SID from A]
4 Route 5 [RNAV/STAR to A] 8 Route 6 [RNAV/SID from A]
3 Route 7 [RNAV/STAR to A]
Table 2 - 1: Sample Traffic Distribution (Geographic)
The above information does little more than confirm the accuracy of the controllers’ assessment and reinforce the concerns of the Operational Manager (which is essential to ensure that all parties understand “the problem”).
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本文链接地址：EUROCONTROL MANUAL FOR AIRSPACE PLANNING 2(91)
