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Recommendation issued to: Airservices Australia

Recommendation details
Output No: R20070011
Date issued: 04 April 2007
Safety action status: Closed - Action Taken
Background: Why this Recommendation was developed

Output text

Safety Issue

Airservices Australia's instrument approach charts did not depict the terrain contours on the plan-view. They also did not depict the terrain profile on the profile-view, although the segment minimum safe altitudes were depicted.

Safety Recommendation

The Australian Transport Safety Bureau recommends that Airservices Australia address this safety issue.

Initial response
Date issued: 25 May 2007
Response from: Airservices Australia
Action status: Closed - Accepted
Response text:

We [Airservices Australia] are concerned that depicting terrain contours on the plan and profile of instrument approach charts may unintentionally create situations that adversely affect flight safety. One concern we have is that the inclusion of this information on the plan of the charts will create chart clutter, making the retrieval of flight critical data from these charts more difficult, with a possible degradation of flight safety. We are also concerned that providing pilots with more information than is required for them to fly the procedure profile could result in inappropriate use of the information. Instrument approach charts are designed to be used for instrument approach to the runway. If pilots fly the procedure profile and adhere to the published minimum safe altitudes for the various segments of the approach, aircraft will be protected from the underlying obstacles and terrain. Deviations below the profile are discouraged by the chart format with minimum altitude blocks shown below the profile. By also depicting the terrain contours on the chart profile, we would not like to create in pilot's minds the false impression that there is room to descend below the published minimum safe altitudes and still be protected from terrain. The Australian position in relation to the depiction of terrain contours on the plan and profile of instrument approach charts was developed in consultation with CASA. As the concerns we have in relation to operational flying and pilot behaviour are not wholly within our competency, Airservices will consult with CASA to determine the most effective safety outcome.

Further correspondence
Date issued: 19 March 2009
Response from: Airservices Australia
Response status: Closed - Accepted
Response text:

Airservices Australia plans to be ICAO complaint with the terrain requirements for Instrument and Approach Landing (IAL) charts, by the end of2009. To comply with the ICAO standards, only six aerodromes have been identified as requiring the inclusion of terrain. It should be noted that Lockhart River is not included. Airservices remains committed to partnering with the regulator, CASA, to further research human factors matters associated with IAL design and depiction of terrain; as aspects of pilot interpretation primarily rests with the intent of the regulatory standards that govern Procedures Design. Airservices is awaiting CASA's direction in this endeavour.

ATSB response:

In relation to recommendation R20070011, the ATSB recognises Airservices Australia's intention to comply with ICAO Annex 4 as meeting the intention of the recommendation. However, the ATSB would appreciate it if you could clarify the reasoning behind the statement in the Airservices response 'To comply with the ICAO standards, only six aerodromes have been identified as requiring the inclusion of terrain. It should be noted that Lockhart River is not included.' With respect to Lockhart River in particular, this conclusion appears to be inconsistent with the material presented on page 154 of the ATSB investigation report into the fatal accident near Lockhart River (200501977). That stated: The ICAO Annex 4 Aeronautical Charts stated: 11.7.2 Relief shall be shown in a manner best suited to the particular elevation characteristics of the area. In areas where relief exceeds 1 200 m (4 000 ft) above the aerodrome elevation within the coverage of the chart or 600 m (2 000 ft) within 11 km (6 NM) of the aerodrome reference point or when final approach or missed approach procedure gradient is steeper than optimal due to terrain, all relief exceeding 150 m (500 ft) above the aerodrome elevation shall be shown by smoothed contour lines, contour values and layer tints printed in brown. Appropriate spot elevations, including the highest elevation within each top contour line, shall also be shown printed in black. ...... The Lockhart River Runway 12 RNAV (GNSS) approach had a final approach gradient greater than the optimum of 3 degrees, and the height of both North Pap (1,614 ft) and South Pap (1,453 ft) had relief higher than 500 ft above the Lockhart River aerodrome which had an elevation of 77 ft. Before we finalise and close this recommendation, it would be appreciated if you could confirm which six aerodromes were identified as requiring the inclusion of terrain and clarify the rationale for the conclusion that the Lockhart River RNAV (GNSS) approach to runway 12 does not meet the intention of Annex 4 as described above.

Further correspondence
Response from: ATSB
Response status: Closed - Accepted
Response text:

The ATSB recognises that Airservices Australia has now redesigned the Lockhart River runway 12 RNAV (GNSS) approach, and that the new approach chart, to be published in the Aeronautical Information Publication amendment on 19 November 2009, also included coloured terrain contour lines on the plan-view diagram (rather than spot heights only). The ATSB accepts that Airservices Australia has now met the intention of the safety recommendation and has closed this safety recommendation - action taken.

Further correspondence
Date issued: 22 January 2010
Response from: Airservices Australia
Response status: Closed - Accepted
Response text:

As expected and requested, Lockhart River RWY 12 RNAV GNSS procedure was the first aerodrome to have terrain included onto the aerodrome plate. This came into effect on 19 November 2009.

Airservices Australia has now completed the remainder of the Lockhart River approaches, and those for Amberley, Flinders and Lord Howe Islands. These procedures will be published with an effective date of 11 March 2010.

Initial progress has been slower than anticipated due to some cartography technical issues that we have now resolved. As advised last year, Airservices Australia will continue to work through the remaining locations on an ongoing basis, and can provide further updates to the ATSB if requested.

 
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Last update 05 April 2012