- European CDM -

1. - European CDM - Substitution on Cancellation To benefit from the animation settings contained within this presentation we suggest you view using the slide show option. To start the show click ‘View - Slide Show’. next page

2. - European CDM - Substitution on Cancellation The Substitution on Cancellation process is proposed as an enhancement to the current European Air Traffic Flow Management system. next step In cases of severe loss of capacity at an airport, Substitution on Cancellation would help airlines to protect their schedules while temporarily reducing demand for that airport to ease the disruption and reduce delays. The following pages illustrate how ... Collaborative Decision Making www.euro-cdm.org Visit the European CDM website at for more information next page

3. Introduction: Flow Management by CFMU Where forecast demand for an area of airspace exceeds the available capacity, Europe’s Central Flow Management Unit (CFMU) creates a regulation. A flight scheduled to pass through a regulation is assigned a slotto constrain the time at which it reaches that busy area. In this way, CFMU ensures that the airspace is not overloaded with traffic. next step If a flight is scheduled to pass through more than one regulation, each regulation will, in general, require a different take-off slot. The regulation that requires the latesttake-off time is termed the Most Penalising Regulation(because it delays the flight the most). It is the most congested area of airspace that flight passes through, and so takes precedence over the others in setting the CFMU slot. So a flight’s take-off slot is determined by its Most Penalising Regulation. next step On occasions, an airport’smovements capacity may be reduced to well below it’s normal operating capacity, for example by fog or by an incident on a runway or taxiway. In order to prevent a large build-up of arriving traffic waiting to land, CFMU will create a regulation, assigning slots to all flights planning to land at the airport. next step If the airport’s capacity is severely reduced, the arrival regulation is likely to be the Most Penalising Regulation for all arriving flights. The next slide gives an example of large delays building up at a capacity-reduced airport... next page

4. An example of a capacity-reduced airport ... Under normal operating conditions, our example Airport has an arrivals capacity of 24 aircraft per hour  12 per hour 07:00 FLT001 07:02 FLT002 07:05 FLT003 07:08 FLT004 07:10 FLT005 07:13 FLT006 07:15 FLT007 07:18 FLT008 07:20 FLT009 07:22 FLT010 07:25 FLT011 07:28 FLT012 07:30 FLT013 07:32 FLT014 07:35 FLT015 07:37 FLT016 07:40 FLT017 07:43 FLT018 07:45 FLT019 07:48 FLT020 07:50 FLT021 07:53 FLT022 07:55 FLT023 07:57 FLT024 08:00 FLT025 07:00 07:05 07:10 07:15 07:20 07:25 07:30 07:35 07:40 07:45 07:50 07:55 08:00 next step next step Airport operations are disrupted, for example by fog, and arrivals capacity is reduced by 50% to only 12 aircraft per hour (one every 5 minutes, on average). Assuming the airport planned to operate at capacity, there is now an over-demand of 12 arrivals per hour. The flights scheduled to arrive in a single hour now need two hours to arrive. Large delays quickly build up. next step A flight scheduled to arrive at: 08:00 will get an arrivalslot of 09:00, 09:00 will get an arrival slot of 11:00. Delays persist even after the airport returns to full capacity because there is a backlog of delayed flights. This backlog will only reduce when there is spare arrival capacity compared with the planned number of arrivals - perhaps during the quieter afternoon period. next step next page

5. Cancellation In the face of these severe delays, airlines may chose to cancel flights to help protect their schedules. Cancelling a flight releases an aircraft and crew that would have been delayed • … on the flight into the disrupted airport • … and again awaiting departure of the return flight. next step When a flight is cancelled, its CFMU slot is released to be used by the next flight in the slot “queue”... …and all subsequent flights in the “queue” are brought forward one place to close the gap. In our example, cancellation of 6 flights would reduce delays for subsequent flights by a total of 30 minutes. next step Cancelling flights also helps Air Traffic Services and the Airport: the best way to reduce the period of disruption resulting from the loss of capacity is to reduce the number of flights going to that airport while the problem remains, and until the backlog of delayed flights is cleared. In our example, cancellation of 6 flights could mean that the backlog is cleared during the quieter afternoon period, instead of delays persisting into the busy evening period. next step However, if a cancellation is made at the last minute, it may be too late for another flight to take the released slot. As a result, the scarce arrivals capacity may actually be wasted, with no reduction in delays. In spite of this, the current European Flow Management system may effectively discourage airlines from cancelling flights in a timely manner. The next slide illustrates how... next page

6. CFMU slot time at arrival regulation STA = Scheduled Time of Arrival CFMU ArrivalSlot Time Flight Origin STA AB123 CDG 09:00 XX001 LHR 09:00 CD234 FRA 09:03 YY001 LHR 09:05 EF345 CDG 09:05 10:55 11:00 11:05 11:10 11:15 GH456 BHX 10:55 XX002 LHR 11:00 YY002 LHR 11:00 IJ567 BRU 10:55 13:55 14:00 14:05 14:10 KL678 AMS 12:00 XX231 CDG 12:00 MN789 ZRH 12:04 15:25 15:30 15:35 OP890 BRU 16:00 XX003 LHR 16:00 QR901 DUB 16:02 18:25 18:30 18:35 How the current Flow Management system can discourage cancellations Note that Airlines XX and YY both have flights from the same departure airport (LHR) at similar times. The original arrivals schedule at our example airport... … and the delayed slots: next step Under today’s Flow Management System, the first airline to cancel a flight is likely to see its passengers (and hence revenue) transfer to the rival airline’s flight. The cancellation just releases a slot that will help reduce delay for that rival flight. next step NewSlot Time cancelled For example: If Airline XX cancels it’s 11:00 flight XX001… its CFMU slot is released to be 11:05 next step 11:10 used by the next flight in the slot “queue”... …and all subsequent flights in the “queue” are brought forward one place and so get a slot 5 minutes earlier. next step 13:50 13:55 14:00 14:05 Now Airline XX’s first arrival from LHR will be at 13:55. 15:20 15:25 15:30 next step XX is likely to lose passengers to Airline YY which can offer an arrival from LHR at 11:05 — passengers from the cancelled XX001, and also from the delayed XX002. 18:20 18:25 18:30 As a result, Airlines XX and YY may each wait until the last minute to cancel their flights, hoping that the other will cancel instead. next step next page

7. How Substitution on Cancellation helps Substitution on Cancellationencourages timely cancellation of flights by allowing the cancelling airline to benefit directly from the released slot. This is achieved by a change in the slot allocation rules in cases of severe disruption at an airport. next step Under Substitution on Cancellation, each slot is temporarily assigned to the airline whose flight occupies it. This means that an airline that cancels a flight can re-use the released slot, to reduce the delay to another of its flights. next step • The airline is encouraged to cancel flights because it sees direct benefit from doing so — and it does not see the released slot going immediately to benefit a rival! • Airlines with several flights arriving at the airport are given more control in theirschedule management, enabling them to use cancellation to best effect. next step The Substitution on Cancellation slot allocation rulescan apply only in cases of severe disruption at an airport, because in that case the arrivals regulation is the Most Penalising Regulation for allarriving flights (it is much more severe than other regulations). Therefore, arriving flights can swap slots with very little risk of other regions of airspace becoming overloaded as a result. Re-running the previous scenariounder Substitution on Cancellation ... next page

8. CFMU ArrivalSlot Time NewSlot Time Flight Origin STA AB123 CDG 09:00 XX001 LHR 09:00 CD234 FRA 09:03 YY001 LHR 09:05 EF345 CDG 09:05 10:55 11:00 11:05 11:10 11:15 GH456 BHX 10:55 XX002 LHR 11:00 YY002 LHR 11:00 IJ567 BRU 10:55 13:55 14:00 14:05 14:10 KL678 AMS 12:00 XX231 CDG 12:00 MN789 ZRH 12:04 15:25 15:30 15:35 OP890 BRU 15:00 XX003 LHR 15:00 QR901 DUB 15:02 18:25 18:30 18:35 Under Substitution on Cancellation ... Each slot is temporarily assigned to the airline whose flight occupies it. next step If Airline XXcancelsXX001 it can re-use the slot for an on-time arrival of XX002. next step Now Airline XX can transferpassengers from the cancelledXX001toXX002, running that flight full. cancelled The passengers of XX001 are not delayed any further by the cancellation of their flight. Furthermore, Airline XX can now use its freed 14:00slot to help its delayedflight XX231, scheduled for 12:00 arrival from another airport. next step 11:00 next step That frees the 15:30 slot, but Airline XX cannot use it, as this is before the scheduled time of its next arrival. 14:00 15:30 18:20 next step 18:25 The 15:30 slot is therefore released back into the ‘pool’. 18:30 As in today's system, each released slot means subsequent flights’ slots are advanced by a few minutes. next page

9. Conclusion Substitution on Cancellation left Airline XX in a better position after cancelling its flight than the current Flow Management system would have. Cancelling one early flight meant that Airline XX could significantlyreduce the disruption to the rest of its daily schedule. • Passengers of flight XX002 had delay reduced by3 hours. • Passengers of flight XX231 from CDG had delay reduced by1½ hours. next step UnderSubstitution on Cancellation,Airlines with several flights arriving at the disrupted airport will be able to use cancellation to better manage their schedules. This direct benefit to the cancelling airline will mean that: next step  more flights are cancelled, cancellations are declared earlier, in time for released slots to be re-used. And hence ... Delays will be reduced for other flights at the disrupted airport. Recovery from the disruption will be faster, benefiting Airport, Air Traffic Services and user airlines alike. next page

10. Notes Substitution on Cancellation offers a way of improving today’s Flow Management system in cases of severe disruption at an airport. It has already been applied successfully in the US. next step Substitution on Cancellation is a good example of Collaborative Decision Making because: • it encourages courses of action that are of mutual benefit to several parties(cancelling flights benefits self and other airlines, Airport and Air Traffic Services); • it puts the decision in the hands of the organisation best placedto make it(Airline Ops decides which of its flights should be cancelled to best manage its schedule). next step As for all applications of CDM, participants will need to agree rulesand proceduresto ensure that Substitution on Cancellation brings optimum benefit. For example: • Is only onesingle substitution allowed, or may the cancelling airline try to re-use the slotsreleased by each substitution (as was shown in the example)? • Substitutionscould also be negotiated between the Operations Centres of different airlines, with the cancelling airline nominating another flight to benefit from its freed slot. Should substitutions between different airlines allowed? - End of Presentation -