IATA European RTC/6 Agenda Item 12.1. Brussels, Belgium Working Paper 12.1. 24-26 October 2000 Page 1 INTERNATIONAL AIR TRANSPORT ASSOCIATION EUROPEAN REGIONAL TECHNICAL CONFERENCE EUROCONTROL, BRUSSELS 24 – 26 October 2000 Agenda Item 12.1. : Expansion of the 8.33 kHz area Expansion of the Application Area of 8.33 kHz Channel Spacing Executive Summary The implementation of 8.33 kHz channels spacing in the core area of Europe has provided the expected short-term frequency release, with the channel needs of the so called 8.33 States being met with a high success rate. At the same time simulations and follow-up action conducted by EUROCONTROL show that if nothing further is done, the aviation part of the VHF band will, by the end of 2002-3, face similar constraint to those experienced before the original implementation of 8.33 kHz channel spacing. The difficulties already being experienced by those States still using 25 kHz spacing further highlight the need for urgent action. This is not unexpected, as it had already been foreseen in the planning stages of the original implementation that it would provide only temporary relief up to about 2003. Initiatives are under way to provide VHF spectrum relief. These include improved frequency management in the whole of Europe and alternative technologies (e.g. VDL Mode 3), but these are not expected to bring appreciable results before 2005-7. Expanding the 8.33 kHz application area horizontally via the structured and co-ordinated retraction of the existing temporary exemptions would provide an effective way of providing spectrum release in the short term, catering for frequency demand up until the time new technologies are expected to provide a more permanent solution. Meeting the demand for frequencies, and thereby preserving the ability of pilots and controller to communicate via voice, is an operational imperative. It is therefore proposed to expand the 8.33 kHz channel spacing area horizontally on 31 October 2002. IATA European RTC/6 Agenda Item 12.1. Brussels, Belgium Working Paper 12.1. 24-26 October 2000 Page 2 INTERNATIONAL AIR TRANSPORT ASSOCIATION EUROPEAN REGIONAL TECHNICAL CONFERENCE EUROCONTROL, BRUSSELS 24-26 October 2000 Expansion of the Application Area of 8.33 kHz Channel Spacing Introduction 1. The ability of pilots and air traffic controllers to communicate via voice is one of the oldest, basic elements of the ATM system. Advances in ground and airborne automation do mean that in the not too distant future we will be using this facility in a different way, with an increasing amount of voice being replaced with data communications. However, even in the most advanced ATM environment, voice communications will continue to play an indispensable role. 2. The resource used to enable voice communications, the aviation spectrum, is limited and the demands being put on it have already resulted in a scarcity of frequencies that can be allocated to the services needing them. In many cases, requests for frequencies go unsatisfied, or less essential services (e.g. automated weather reporting) are terminated with the corresponding frequency being reallocated to the more essential service. 3. An examination of ongoing and planned ATM enhancements shows conclusively that the need for additional frequencies will continue to increase for the foreseeable future. The main sources of this requirement are: a. The introduction of Controller-Pilot Data Link Communications (CPDLC) will not take away the need for voice channels in sectors using CPDLC; b. Airspace structure developments and the introduction of RVSM will require new sectors in some States and these will need new frequencies; c. New control centres. In Europe CEATS will require its own set of frequencies and these cannot all be provided by what may be freed from the national facilities; d. VHF Digital Link (VDL). In order to eliminate interference between voice and data modes, guard bands will need to be implemented around the frequencies allocated to VDL. While the exact number of frequencies implicated in this is still the subject of further study, a realistic expectation is that 10-15 25 kHz channels will have to be released in Europe for this purpose. The eventual need for additional VDL frequencies will only increase this number. e. To meet additional demand and/or to re-allocate existing frequencies, a certain flexibility is needed in the frequency allocation process. This flexibility can only be provided if there is a sufficient number of “free” frequencies, which can be moved and shifted around. With the part of the aviation spectrum using 25 kHz channel spacing nearing saturation in Europe, the required flexibility IATA European RTC/6 Agenda Item 12.1. Brussels, Belgium Working Paper 12.1. 24-26 October 2000 Page 3 disappears and this makes the frequency management process extremely difficult. Additional frequencies are needed to restore flexibility. 4. Considering that the ability for pilots and controllers to talk to each other via voice will continue to exist as a primary element of the ATM system, it is fair to say that meeting the demand for VHF frequencies is an operational imperative. Cost effective ways must be found to satisfy this imperative, but it would be wrong to make this contingent upon extra benefit considerations. 5. The European answer to the frequency shortage had been the introduction of 8.33 kHz channel spacing for services above FL245 and with the initial application area limited to the core of Europe. Discussion 6. The implementation of 8.33 kHz channel spacing has indeed delivered the expected short-term frequency benefit, but this was obviously limited to the States which participated in the actual implementation. It should be noted that the less then optimum operational introduction of the new frequencies was due to circumstances (e.g. lack of controllers to man the new sectors) quite unrelated to the new channel spacing. 7. The benefit of 8.33 kHz channel spacing in satisfying the need for new frequencies is amply demonstrated by a comparison of the success rate in 8.33 kHz participating States and that in 25 kHz States. According to data made available from the European Air Navigation Planning Group’s (EANPG) Frequency Management Group (FMG) 8th Block Planning Meeting in December 1999, the success rate for 8.33 kHz States was 100 %, while the success rate for 25 kHz States only 43 %. 8. This very low result for the 25 kHz States can be traced to the generally poor quality of the frequency management process in Europe and, more significantly, to the very large number of shifts needed to actually implement an allocated new frequency (in some cases as many as 32 to implement 47 new frequencies). This is compounded by the fact that currently there is no mandatory requirement for States to actually implement the frequency assignments/shifts as planned by the Block Planning Meetings. 9. Simulations conducted by EUROCONTROL, based on the forecast increase in frequency demand, show that, in addition to the current difficulties in meeting the demands in States using 25 kHz channel spacing, if nothing is done, by 2002-3, the VHF spectrum in Europe will once again face similar constraints to those experienced before the initial implementation of 8.33 kHz channel spacing. Note: This is not unexpected and had been predicted in 1996 in the “Plan for the 8.33 kHz Channel Spacing Implementation in Europe – Edition 2.0”. 10. While a decision to address the shortcomings of the European frequency management process (c.f. MATSE6) will undoubtedly result in some improvement, this is not expected to release sufficient spectrum in time to alleviate the upcoming problem. IATA European RTC/6 Agenda Item 12.1. Brussels, Belgium Working Paper 12.1. 24-26 October 2000 Page 4 Possible Solutions 11. In searching for a solution to the frequency shortage, the very short period remaining until its expected occurrence must be kept in mind. The following alternatives have been examined: a. Extension of the VHF spectrum. In view of the fierce competition for spectrum by other industries, achieving this is highly improbable. In any case, this solution is very costly, considering the retrofit implications. Furthermore, any such extension could only be expected to occur at a date well beyond the stated requirement. b. Better frequency management. Achieving this in Europe is essential, however, as mentioned above, even a much improved frequency management process will be unable to release sufficient spectrum and even modest improvements will take several years to implement. c. Introduction of VDL. As already mentioned, sectors using CPDLC will continue to have a need for a dedicated voice channel. d. Wide-band voice/data. A proposal to use part of the C-band, currently allocated to MLS, with Code Division Multiple Access (CDMA) technology, is currently being examined. However, a lot of work remains to be done, and implementation, if any, cannot be envisaged before 2010. Even then, this solution would work only in the TMA/Airport environment. e. Wireless gatelink. While services on wireless gatelink are expected to be increasingly available in the near future, this solution is strictly for the airport environment. While it will provide some VHF spectrum congestion relief at airports, it does not address the problem being faced by services outside that area. f. VDL Mode 4. Currently being considered for surveillance services only. A decision for industry-wide application beyond surveillance is not expected within the problem-time frame. g. VDL Mode 3. VDL Mode 3 is an integral part of the US NEXCOM program. In its ultimate form it can provide combined digital voice/data service, however, initial implementation in the US foresees only digital voice and this in the timeframe 2007+. Europe does not, as yet, have a comparable program. Even with a swift implementation decision, VDL Mode 3 is well outside the problem-time frame. h. Vertical expansion of the 8.33 kHz application volume. Simulations indicate that a vertical expansion (below FL245/FL195) of the 8.33 kHz application volume would be far less efficient in terms of frequency release than the original 8.33 kHz implementation. It would also impact a very large number of aircraft and several new categories of airspace users. Considering the costs and logistics involved, no implementation before 2007 can even be considered. Apart from the fact that this in itself puts this solution firmly IATA European RTC/6 Agenda Item 12.1. Brussels, Belgium Working Paper 12.1. 24-26 October 2000 Page 5 beyond the problem time frame, the wisdom of extending an analogue system into the lower airspace at a time by which digital systems are expected to mature is highly questionable. The airspace user community has repeatedly voiced the opinion that this was a non-option and should not be further considered. i. Horizontal expansion of the 8.33 kHz application area. The high success rate of satisfying frequency needs in the existing 8.33 kHz States makes this option very attractive. Such expansion involves only the horizontal extension of already existing provisions and procedures, with the additional impact on airspace users being sufficiently limited to make implementation by the 3rd quarter of 2002 a realistic proposal. Proposed Solution 12. From the list of options above, it is clear that only one solution is available to meet the challenge of the problem time-frame, namely horizontal expansion of the 8.33 kHz application area. This option offers the following additional advantages: a. Regulatory background. The carriage and operation of 8.33 kHz capable radio equipment is already mandatory in the whole of the ICAO EUR Region, as published in Doc. 7030, Regional Supplementary Procedures-EUR. Non-8.33 equipped aircraft are currently allowed to operate in certain parts of the EUR region on the basis of temporary exemptions published by a number of States. However, these exemptions have always been identified as “temporary” which can be withdrawn after appropriate consultation with the airspace users (8.33 User Guide para. 7.4 refers). Therefore, extension horizontally involves only a structured retraction of some or all exemptions and does not need additional ICAO provisions. b. Number of aircraft to be retrofitted. The number of aircraft to be retrofitted with 8.33 kHz capability is estimated to be in the order of 900. This number was arrived at using the very comprehensive fleet survey that had been conducted before the original 8.33 kHz implementation. At that time a thorough inventory of all airlines (scheduled and non-scheduled) operating anywhere in the EUR region had been prepared. Airlines which did not responding to the first approach to supply existing and planned fleet data were followed up individually. The number of aircraft to be retrofitted in case of a horizontal expansion has now been calculated on the basis of the known fleet numbers involved in the first implementation. Since practice has shown that this number was very accurate, the number of aircraft still to be fitted can also be considered reasonably accurate, even if possible changes within the past 18 months are taken into account. In any case, a new survey will be conducted to confirm the numbers, but it is not expected to result in a substantially different value. c. Costs. Based on the per-airframe cost of USD 40.000, the costs for 900 aircraft would come to USD 36.000.000. The costs incurred by ground radio replacement/upgrades are more difficult to estimate in view of the many IATA European RTC/6 Agenda Item 12.1. Brussels, Belgium Working Paper 12.1. 24-26 October 2000 Page 6 different types of equipment and environments. Since it is known that several of the candidate 8.33 States are in the process of procuring new ground radios in the 2001-2 time frame, as part of their normal renewal activity, and since most new radios will be 8.33 capable, the actual ground radio costs attributable to 8.33 expansion will be limited. d. Logistics. Although the original 8.33 implementation program has now been officially terminated, the modus operandi employed is well rehearsed. The instruments used (Project Management Cell, Technical Retrofit Meeting, Contact Persons’ Meeting, etc.) can be activated again at any time, with participation slightly adjusted to take account of the new 8.33 States. Even this can be limited, since most of the current candidate States had been involved in the original implementation in their capacity as “buffer” States. Documentation (User Guide, AICs, AIP entries, Letters of Agreement) has all been developed for the original implementation. Most of these can be re-used with minimal changes, resulting in substantial savings of effort. With the majority of exemptions likely to be withdrawn, the operational environment will become simpler resulting in reduced training effort for airspace users. e. States’ willingness to implement. Most States in the proposed horizontal expansion area have already indicated their plans to implement the new channel spacing on the proposed date (31st October 2002, see below). The implementation date may be later in some States, but they would still participate in the expansion exercise to facilitate co-ordination. Other States may join the implementation purely on a strategic basis, to ensure the largest possible homogenous expansion area. f. Flexibility in the number of States actually joining. The spectrum release potential of horizontal expansion is directly related to the number of States involved. The larger this number, the greater the benefit. However, there is no set minimum number to make the exercise worthwhile. This means that even if a number of States decide not to participate, substantial spectrum benefits can be realised. In any case, with the number of States already having indicated their desire to participate, horizontal expansion will bring enough spectrum release to meet the forecast demand up to about 2007. g. Time to implementation. In view of the relatively low number of aircraft to be retrofitted, the already existing plans for ground radio upgrades and the reusability of the logistics arrangements and the continued applicability of existing regulatory provisions, time to implementation can be short, and accordingly 31st October 2002 is being proposed. This date fits well with the expected occurrence and increasing severity of spectrum congestion in Europe. 13. Based on the experience with initial 8.33 kHz implementation and simulations of an expanded area, horizontal expansion of the 8.33 kHz application area would result in the following benefits: a. When a frequency, originally operated on 25 kHz spacing, is converted to 8.33 kHz spacing on the matching centre 8.33 kHz channel, it can immediately and IATA European RTC/6 Agenda Item 12.1. Brussels, Belgium Working Paper 12.1. 24-26 October 2000 Page 7 without any shifts whatsoever accommodate the two shoulder frequencies under the coverage of the original 25 kHz frequency. Consequently, the chances for successful implementation are increased drastically, as evidenced by the success rate in the current 8.33 kHz area. b. While the spectrum benefits are spread across the whole of the VHF band, the majority of the benefits accrue within the current 25 kHz environment, exactly where it will be needed most c. The newly created frequencies mean that the frequency management process no longer has to operate in a near saturation (and therefore almost paralysed) mode, since the necessary flexibility in reallocating existing frequencies as required is restored. d. The new frequencies enable the meeting of new frequency demand without requiring extensive shifting. 14. Consequently it is proposed to expand the 8.33 kHz application area horizontally via the structured retraction of current exemptions starting on 31 October 2002. The expanded area would cover as a minimum the States adjacent to the current 8.33 area, and may eventually extend beyond those States to the outer ECAC boundary. The exact list of States is still to be determined. IATA Involvement 15. IATA’s European Operations and Infrastructure Office has played a pivotal role in the original 8.33 kHz implementation. Not only did IATA provide a constant line of information to and from the airline community, but it also helped in the development of procedures and monitoring facilities. The value of this contribution has been amply recognised by the airlines, air traffic service providers and EUROCONTROL. 16. While the effort involved in the horizontal expansion of the 8.33 kHz application area is smaller than that for the original implementation, IATA’s involvement on a similar level will be essential if the same, smooth implementation is to be assured. 17. It is estimated that the effort involved will be between 5-10 % of the time of one person until the end of 2001 and about 5 % thereafter until the implementation date. Therefore no additional resource will be required. Program risks 18. The need to release spectrum as soon as possible has resulted in an implementation date that is only 2 years from program go-ahead. Meeting this deadline will require careful planning and tight control of the program, as well as full co-operation of airlines, equipment manufacturers and ATS providers. IATA European RTC/6 Agenda Item 12.1. Brussels, Belgium Working Paper 12.1. 24-26 October 2000 Page 8 19. Some of the aircraft types which will have to be retrofitted may not have been involved in the original implementation and this may need individual attention. However, the methods employed with success in the first implementation should be sufficient, in spite of the different environment. 20. UHF coverage is spotty or none-existent in some of the 8.33 candidate States and this can create complications for State Aircraft. Close co-ordination with operators of State Aircraft and the States concerned will be required to ensure a smooth transition. Conclusions 21. The RTC is invited to: 1. Note the expectation that the need for frequencies will continue to increase; 2. Agree that meeting the frequency demand is an operational imperative. 3. Endorse the horizontal expansion of the 8.33 kHz application area as the only available solution to meet the forecast frequency demand; 4. Endorse 31st October 2002 as the date on which the majority of the current 8.33 kHz exemptions will be withdrawn; 5. Urge airlines that will have to retrofit aircraft under the new mandate to institute the necessary in-house programs with all speed. IATA European RTC/6 Agenda Item 12.1. Brussels, Belgium Attachment 1 to Working Paper 12.1. 24-26 October 2000 Page 9 Attachment 1. Figure 1 – Percentage of actual and forecast satisfied demand versus actual and forecast demand in candidate expansion States (Source: EUROCONTROL) Percentage of Satisfied Neeeds V/S Demand Supply / demand (%) Expansion Countries 100.00 satisfaction % 80.00 without Horizontal 60.00 Expansion 40.00 satisfaction % with 20.00 Horizontal Expansion 0.00 satisfaction % with 01 03 05 07 P4 P6 P8 combined 20 20 20 20 /B /B /B 97 98 99 Horizontal and 19 19 19 Vertical Expansion 1. The above graph was generated using data from the ICAO EANPG FMG and Authorative Representative Body (ARB) frequency management activities over the past five years, with the baseline taking account of States’ normal demand per type of service, actually achieved implementation rates, States’ stated future frequency needs and the possible 8.33 kHz expansion scenarios. 2. The graph illustrates: a. the critical situation before 8.33 kHz implementation (success rate 20%); b. the period when the situation will once again become critical (2002-3), if nothing is done; c. how the 8.33 kHz expansion would provide, for a limited period of time, the spectrum release comparable with the initial implementation; d. the marginal improvement in spectrum release that may be provided by vertical expansion. 3. In respect of 2/b above, it should be noted that this is not unexpected and is in line with the relevant predictions in 1996 as published in the “Plan for the 8.33 kHz Channel Spacing Implementation in Europe – Edition 2.0”. 4. In respect of 2/c above, it should be recalled that at the time the initial implementation of 8.33 kHz was being planned by the ICAO EANPG (EANPG/38-November 1996), it was already recognised that initial implementation, limited to the core area of Europe, would provide only a short- term solution, with expansion becoming inevitable if the demand for VHF channels continued to increase at a rate similar to the increase of traffic demand. In fact, this expectation was behind the decision to make the carriage and operation of 8.33 kHz capable radio equipment mandatory in the whole of the ICAO EUR Region, with temporary exemptions being made available in States where the new channel spacing was not yet needed.
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