Manual of Standards Part 173—Standards Applicable to Instrument Flight Procedure Design
(a) lead radials;(a) lead radials;
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(b) revised instrument approach procedures where the final course has been re-aligned by 3° or more.
7.1.1.2 Validation of an instrument flight procedure comprises:
(a) a review of the draft procedures from an operational perspective conducted by the validation pilot; and
(b) a validation flight check.
7.1.1.3 The process of instrument approach procedure design focuses on those controlling obstacles that affect the procedure. This focus is facilitated through the use of various obstacle and terrain databases. The purpose of flight validation is to verify database information, to check all obstacles (including the identification of any unforeseen obstacles) that affect the safety of the procedure, and to assess the 'flyability' of the procedure.
7.1.2 Maps and Charts
7.1.2.1 Validation flights must carry maps and charts that meet the following requirements:
(a) An appropriate topographical map of at least 1:250,000 scale or larger scale. (A scale of 1:100,000 may be necessary in areas of precipitous terrain and when checking circling, final and missed approach segments.) The map must be marked by the procedure designer with:
(i) final segment splay/s;
(ii) missed approach segment splay/s;
(iii) circling area for the appropriate categories or category groups; and
(iv) controlling obstacles for each segment, MSA and holding pattern.
7.1.3 Weather
7.1.3.1 Validation flights must be undertaken in daylight hours and in VMC. The ceiling should be above the initial approach altitude (preferably above the 25 NM MSA).
7.1.4 Responsibilities
7.1.4.1 The Chief Designer is responsible for the organisation of flight validation activities.
7.1.4.2 The procedure design flight validation crew member is responsible for the planning of validation flights.
7.1.5 Aircraft
7.1.5.1 The standard for the type of aircraft to be used for flight validation of a design is an aircraft that has performance capabilities appropriate to the type and design of the procedure.
7.1.5.2 The aircraft must be of a configuration that permits good visibility and adequate cabin dimensions permitting maps and other documents to be readily referred to in flight.
7.1.5.3 The type of aircraft is to be approved by the CASA validation pilot.
7.1.5.4 An aircraft flight simulator, approved by the CASA validation pilot may be used to verify database information and flyability of the procedure.
7.1.6 Crew
7.1.6.1 The minimum crew is a pilot and a procedure designer.
7.1.6.2 Only persons involved in the validation procedure being conducted in an aircraft are to be carried in the aircraft.
7.1.7 Conduct of Operations
7.1.7.1 Judgment must be applied when planning the validation flight to minimise the time spent on task. Efficiently linked segments and avoiding those areas where obstacles will have no affect on the procedure will help to achieve this objective.
7.1.7.2 Crew responsibilities:
(a) the pilot must fly the aircraft;
(b) the procedure designer must:
(i) visually navigate the aircraft; and
(ii) direct the pilot by providing tracks and altitudes to fly; and
(iii) note any differences to the pre-determined list of obstacles;
(c) both crew members are responsible for lookout;
(d) when flying the segments of the procedure, the aircraft should be configured to emulate the highest category aircraft for which the procedures are planned—this will be particularly important when the length of a particular segment is short;
(e) when checking individual obstacles, the highest practical speed, commensurate with fuel reserves should be used;
(f) during the validation process, gear should be up and any lights that increase the visibility of the aircraft should be turned on.
7.1.8 Environment
7.1.8.1 Prior to conducting validation of a procedure in a populated or environmentally sensitive area, the procedure designer should:
(a) discuss with the validation pilot any options for reducing the environmental impact of the flight.
(b) as appropriate, advise the aerodrome operator, ATC, local CASA office and any other affected persons, of the details of the proposed operation, including advice that low-level flying will be required.
(c) advise the CASA Public Relations office in sufficient time to permit a press release to be issued.
7.1.9 Validation of the Procedure
7.1.9.1 The actual sequence of checks is not mandated in this document, as each situation will suggest the most economical way of arranging the elements of the task.
7.1.9.2 The specified altitude(s) for the validation of an instrument approach segment is/are equal to the published segment minimum altitude(s) minus the Minimum Obstacle Clearance (MOC) applicable to the segment.
7.1.9.3 Each controlling obstacle and/or procedure segment must be checked at a specified altitude(s) to validate the obstacle data used and to determine whether there are any unforeseen obstacles extending above the specified altitude. Such a case would indicate that the unforeseen obstacle is higher than the controlling obstacle and that it may affect the procedure. If such an unforeseen obstacle is observed, its location and observed height AMSL must be recorded for subsequent detailed analysis by the procedure designer.
7.1.10 25 and 10 NM Minimum Sector Altitude
7.1.10.1 Each 25 NM sector, or the 25 NM circle, and the 10 NM circle must be checked at their specified altitudes. 25 NM and 10 NM MSAs include obstacles out to 30 NM and 15 NM respectively from the navigation aid or ARP upon which the MSA is based. Checks must include the controlling obstacle in addition to other obviously high terrain or obstacles. Where the sector/circle does not exhibit greatly differing terrain elevations, judgment may be exercised regarding the tracks flown to provide a full coverage of the area.
7.1.11 Terminal Arrival Altitude (TAA)
7.1.11.1 Each Terminal Arrival Altitude (TAA) sector must be checked at its specified altitude. TAAs include obstacles out to 30 NM from the initial approach fix upon which the TAA is based. Checks must include the controlling obstacle in addition to other obviously high terrain or obstacles. Where adjacent TAAs do not have greatly differing terrain elevations, judgement may be exercised regarding the tracks flown to provide a full coverage of the area.
Note: This paragraph is included in anticipation of Terminal Arrival Altitudes being included in the next amendment to PANS-OPS.
7.1.12 DME/GPS Arrival Procedures
7.1.12.1 Controlling obstacles will be determined by the procedure designer for each segment within each sector of the arrival procedure. These obstacles must be checked at the specified altitude. Additionally, each step in the final and intermediate segments must be flown at the OIS altitude. Each step must be flown around the radius of the step plus 1 NM, between the lateral limits of the sector splay. The controlling obstacles for these steps can be checked during the process of flying the steps.
7.1.13 Circling Area
7.1.13.1 The circling area must be checked by flying around the lateral limit of the circling area for the lowest supported aircraft category or group (usually CAT A/B) at the specified altitude for that category and looking in towards the airfield. In this manner, both the controlling obstacle and any unforeseen obstacles will be seen in the one action.
7.1.13.2 The same procedure is then used to check obstacles in the circling area for the next highest supported aircraft category or group (CAT C/D). By conducting the inner check first, obstacles that may affect all categories can be readily identified.
7.1.13.3 Circling area checks are not conducted in those areas designated 'No Circling'.
7.1.14 Final and Intermediate Segments
7.1.14.1 The final and, where implemented, the intermediate segment, must be checked as follows:
(a) fly from overhead the MAPT at the specified altitude for the final segment, at 90° to the final track, to the limit of the splay;
(b) turn to fly away from the airfield along the lateral edge of the splay at the final specified altitude to abeam the step down fix (if implemented) or abeam the FAF:
(i) abeam the step down fix, climb to the specified altitude for the next section of the final segment;
(ii) terminate abeam the FAF unless an intermediate segment is implemented, in which case continue along the lateral limit of the intermediate segment at the intermediate specified altitude until abeam the IF and terminate at that point;
(iii) during this process look across the splay to identify the controlling obstacle and any unforeseen obstacles;
(c) conduct the same process on the opposite side of the splay, but looking in the opposite direction;
(d) if the terrain and visibility are such that an unobstructed view can be had from one side of the splay to the other, the procedure outlined above can be shortened by flying along the centreline of the splay at the appropriate specified altitude.
7.1.15 Missed Approach Segment
7.1.15.1 The missed approach segment must be checked in accordance with the following:
(a) position the aircraft at the start of climb point, determined in accordance with Figure 7‑1, at the specified level;
(b) fly the aircraft along the missed approach track, climbing at a rate that equates to the missed approach design gradient, until in the final phase of the missed approach.
7.1.15.2 For environments with numerous obstacles, the missed approach segment should be checked by flying the missed approach splays in a similar manner to that specified for the final and intermediate segments, but climbing along the lateral edge of the splay, in accordance with the missed approach design gradient, until in the final phase of the missed approach.
7.1.15.3 The validation start of climb must be determined in accordance with Figure 7‑1
Validation start of climb
Figure 7‑1: Validation start of climb
7.1.16 Linking the Final and Missed Approach Segments
7.1.16.1 Figure 7‑2 shows a method for linking the checks of the final and missed approach segments.
Final and missed approach segments
Figure 7‑2: Final and missed approach segments
7.1.17 Holding and Initial Segments
7.1.17.1 The controlling obstacles for the holding and initial segments must be checked at their specified altitude and any unforeseen obstacles identified. These checks may be combined with the checks of the DME/GPS Arrival Procedure.
7.1.18 ‘Flyability’ Check
7.1.18.1 The complete design, as proposed for publication, must be checked for operational acceptability. This check should be flown at the maximum segment speeds for the fastest category of aircraft served by the procedure. The check includes:
(a) lead radials;
(b) outbound tracks (highest use category);
(c) outbound timing (highest use category);
(d) descent gradients;
(e) bank angle for turn onto final during base turns;
(f) runway alignment and distance from runway at the minima;
(g) descent gradient from the minima for a straight-in approach;
(h) the missed approach; and
(i) acceptability of initial and intermediate segment lengths for GPS approaches.
7.1.19 Windsocks
7.1.19.1 For runway aligned approaches where a windsock is not located adjacent to the runway threshold, it must be confirmed that a windsock is visible when the aircraft is at the MDA, in accordance with CAO 92.2.
7.1.20 Flight Safety
7.1.20.1 Some of these checks will be conducted close to obstacles and in close proximity to airfields, therefore a visual-and-listening watch by all crewmembers is essential. In particular, the following points should be noted:
(a) pay particular attention to airspeed during manoeuvres with high angles of bank;
(b) be vigilant for inconspicuous towers and power transmission lines. Some towers are painted in low-contrast colours;
(c) be alert for birds, particularly near bushfire smoke and over mountainous areas or inland water bodies.
7.1.21 Traffic
7.1.21.1 Give priority to other traffic when validation requirements conflict with existing traffic patterns.
7.1.22 Environmental Issues
7.1.22.1 Try to:
(a) avoid flight over built-up areas, concentrations of animals, or other noise-sensitive areas;
(b) avoid repetitious flight over the same area or areas, and
(c) minimise high RPM noise.
7.1.23 Reporting
7.1.23.1 A flight validation report form, prepared for the applicable aerodrome, must be attached as part of the validation flight request package. The standard report format is shown in Section 7.2.
7.1.23.2 Following completion of the validation flight:
(a) the pilot must complete the validation report; and
(b) the procedure designer must process the report form and complete the follow-up action.
7.1.24 Pilots
7.1.24.1 The standard for the qualifications and experience of Pilots-in-Command of instrument flight procedure validation flights is:
(a) ATPL;
(b) current command instrument rating, endorsed for the type of procedure under validation;
(c) relevant experience in multi-engine IFR procedures;
(d) completion of a course in PANS-OPS procedures design principles;
(e) a thorough knowledge of ICAO PANS-OPS procedures design principles and methods;
(f) adequate knowledge of the design of procedures in accordance with the MOS;
(g) satisfactory completion of a flight validation course conducted by CASA and possession of a letter of competency issued by CASA certifying his/her competence to conduct flight validation;
(h) satisfactory completion of a course in aerodrome lighting and visual approach slope guidance systems conducted by CASA and possession of a letter of competency issued by CASA certifying his/her competence to conduct aerodrome lighting inspections;
(i) a low flying permit issued in accordance with CAR 157(4)(b); and
(j) completion of a procedure flight validation flight within the previous year.
7.1.24.2 Helicopter procedures are to be validated by pilots who, in addition to the above qualifications, are familiar with helicopter procedure design and operations.
7.1.24.3 Should the validation pilot not be qualified as pilot-in-command of a helicopter, aircraft or flight simulator to be used for a validation flight, another pilot may be assigned to be the pilot in command provided that the validation pilot occupies a seat in the cockpit and directs the conduct of the validation.