The aim of the ‘RTF policy’ is to reduce workload in the air and on the ground by the development of simple, clear and standard procedures. These procedures, considered as basic, for adoption in the event of RTF, should be collated and issued in a single ICAO document. Any other particular procedures for local application, should be published in State AIP in conformity with an approved ICAO model, taking into account the necessity to produce a standardised format in simple terms for both pilot and controller. Today’s situation is quite different, and with the recent ‘classification of airspace’ has further need for clarification, hence the reason for this item on the work study programme.

As reported at the Christchurch Conference (WP005, Agenda B.7.12) , a short survey was initiated to provide a concise and reliable statistical basis upon which analysis could be conducted and further policy recommended if required.

Only 13 questionnaires were returned to date, not the result hoped for, and questions whether the information provides reliable statistical basis on which to draw conclusions.
The findings from the questionnaire are as follows:

• 100% apply RTF failure procedures consistent with ICAO, over 90% of their airspace. This fact can be considered as a demonstration of the necessity to have a clear ICAO basic procedure.
• 63.6% stated that the current procedures are relevant to all the airspace with no significant difference between lower and upper, whilst it is reported by 36.4% that most RTF’s occur in the lower airspace only. In our opinion this fact indicates the necessity for ICAO to update the RTF procedures particular the lower airspace , TMA’s and CTR’s. Evidence for this is by the large number of ‘specific national and/or local RTF procedures established in the vicinity of major airports or TMA’s. These specific rules generally follow principles contrary to the RTF procedures e.g. descent in VMC for VFR traffic.
• 77% have a national regulation for ground equipment RTF, while others have only local rules or a combination of both. This fact demonstrates the difficulty to establish common basic rules for both ground and air RTF therefore only the air RTF is considered in this paper.

With reference to the ICAO regulation contained in Annex 2 ( para 3,6,5 ), Doc 4444 part III – 17 and Annex 10 para 5.2.2.7 The provision of ATC to other flights operating in the airspace where an RTF has occurred is based on the proviso that the RTF aircraft will comply with Annex 2 para 3.6.5.2.2. This is subject to IMC or marginal meteorological conditions only. It is recommended that ICAO should investigate that the current set of RTF rules apply without impairing safety.

Under the new airspace classification when a VFR flight operated as a controlled flight ( Annex 2 3.6.5.1 , Annex 11 3.1 in B,C,D classes of airspace experiences RT failure.

The present set of RT failure rules relate only to VMC and IMC conditions. The new ATS airspace classification introduced different minima for VMC ( class B is different from C.) ICAO should clarify the specific action required with each particular situation applying Doc 4444 III 17.3 ( the ATCO shall maintain separation between the RF aircraft and other aircraft…) when required.

The present ‘state of the art’ ATC technology should be considered by ICAO to establish a common basic procedure to permit the implementation of some national regulations to comply with Doc 4444 par III 17.4 (b) obligation (‘….a different action may be taken by ATC units through the use of electronic or other aids… without impairing safety’).

To Conclude

There appears to be a difference between the official ICAO RTF rules and the present situation in ATC, particularly with reference to the new ATS airspace classification and related procedure in RTF situation. Consideration should be given to the RTF procedures in the lower airspace. ICAO basic procedures appear to be unspecified and generally not applicable, especially with regard to SVFR, Controlled VFR and IFR in VMC operating in the vicinity of a major airport. A new comprehensive set of RTF rules should be examined by ICAO , taking into account the ‘state of art’ of ATC equipment in particular the use of specific electronic aids , in order to permit the use of such technology by ATC to resolve the RTF. It is requested that conference decide that in light of the poor response to the questionnaire and the conclusions drawn as to whether the subject be progressed any further, and also whether the findings to date should be passed to ICAO for further action.