Publication: Magyar Közlöny
Issue: MK-2007-70 (Year: 2007, Number: 70)
Era: 2004-2010
Section: Melléklet a 2007. évi XLVI. törvényhez
Paragraph Index: 3902

c) the trend of the failure rates. 23/11/06 ATT G-32 2007/70/II. szám Attac ment G Annex 10 — Aeronautical Communications 11.2.9 The minimum acceptable confidence level for acceptance/rejection is 60 per cent. Depending on the service level of the MLS, this may result in different evaluation periods. To assess the influence of the airport environment, a minimal evaluation period of one year is typically required for a new type of installation at that particular airport. It may be possible to reduce this period in cases where the operating environment is well controlled and similar to other proven installations. Subsequent installation of the same type of equipment under similar operational and environmental conditions may follow different evaluation periods. Typically, these minimal periods for subsequent installations are for Level 2, 1 600 hours, for Level 3, 3 200 hours and for Level 4, at least 6 400 hours. Where several identical systems are being operated under similar conditions, it may be possible to base the assessment on the cumulative operating hours of all the systems. This will result in a reduced evaluation period. 11.2.10 During the evaluation period it should be decided for each outage if it is caused by a design failure or if it is caused by a failure of a component due to its normal failure rate. Design failures are, for instance, operating components beyond their specification (overheating, overcurrent, overvoltage, etc., conditions). These design failures should be dealt with such that the operating condition is brought back to the normal operating condition of the component or that the component is replaced with a part suitable for the operating conditions. If the design failure is treated in this way, the evaluation may continue and this outage is not counted, assuming that there is a high probability that this design failure will not occur again. The same applies to outages due to any causes which can be mitigated by permanent changes to the operating conditions. 11.2.11 A suitable method to assess the behaviour of a particular installation is to keep the records and calculate the average MTBO over the last five to eight failures of the equipment. A typical record of this method is given in Figures G-35A and G-35B. 11.2.12 During the equipment evaluation, and subsequent to its introduction into operational service, records have to be maintained of all equipment failures or outages to confirm retention of the desired continuity of service. Note.— If an equipment requires redundant or standby units to achieve the required continuity of service, an arrangement such as that described in 11.3.4 is required to assure that the standby equipment is available when needed. 11.3 Additional considerations concerning continuity of service and integrity 11.3.1 The stringent requirement for integrity and continuity of service essential for Category III operations requires equipment having adequate assurance against failures. Reliability of the ground equipment must be very high, so as to ensure that safety during the critical phase of approach and landing is not impaired by a ground equipment failure when the aircraft is at such a height or attitude that it is unable to take safe corrective action. A high probability of performance within the specified limits has to be ensured. Facility reliability in terms of MTBF clearly has to be related on a system basis to the probability of failure which may affect any characteristic of the total signal-in-space. 11.3.2 The following configuration is an example of a redundant equipment arrangement that is likely to meet the objectives for integrity and continuity of service Levels 3 and 4. The azimuth facility consists of two transmitters and an associated monitor system performing the following functions:

Source: https://magyarkozlony.hu/hivatalos-lapok/4c6310a937d14bac566ee9c9d944896656c292dd/dokumentumok/5a6ac3c6db12e692ae41096677ad5f072d2cc9f3/letoltes