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Recommendation issued to: Civil Aviation Safety Authority

Recommendation details
Output No: R20030213
Date issued: 06 November 2003
Safety action status:
Background:

HISTORY OF THE FLIGHT

At 2109 EST on 17 October 2003, a pilot, crewman and paramedic operating a Bell 407 helicopter, registered VH-HTD, were tasked to fly from Mackay to Hamilton Island, Queensland, to transport an injured patient back to Mackay. The flight was planned as a visual operation at night and departed at approximately 2135. When the helicopter did not arrive at Hamilton Island, a search was initiated and a search helicopter crew later sighted the wreckage of HTD floating in the water. Some time later, marine rescue craft arrived and commenced a search, but no survivors were located.

Air Traffic Services recorded radar information indicated that the helicopter, while tracking north-northwest, was flying between 2,900 ft and 3,100 ft for the majority of the flight. It subsequently climbed to 3,700 ft and performed a number of abrupt manoeuvres before descending to 2,700 ft and disappearing from radar coverage.

A weather report provided by the Bureau of Meteorology indicated that, at the time of the occurrence, there was scattered cloud at 2,900 ft and broken cloud at 9,800 ft and no moon. Moonrise that night was expected to occur at 6 minutes after midnight.

During the investigation, ATSB investigators conducted a night flight in similar environmental conditions, at the same altitude and track towards Hamilton Island. They reported that while tracking north-northwest in the area of the accident, it was very dark with no ground or celestial illumination visible and no discernible horizon.


SAFETY DEFICIENCY

During the course of the investigation, a safety deficiency relating to visual operations at night was identified.

General requirements for visual operations are contained in Aeronautical Information Publication (AIP) ENR 1.2 paragraph 2.6. Flights under the Visual Flight Rules (VFR), for both day and night operations, are required to be conducted in accordance with various provisions, including those relating to flight visibility and distance from cloud. When flying outside controlled airspace below 10,000 ft, the required flight visibility is 5,000 m. There is also a requirement for 1,500 m horizontal and 1,000 ft vertical separation from cloud when flying above 3,000 ft above mean sea level, or 1,000 ft above ground level (whichever is the higher). Pilots operating at or below 3,000 ft are required to remain clear of cloud and in sight of ground or water.

The AIP does not require pilots to consider the amount of external visual reference that is likely to be available for a visual flight conducted at night. In particular, it does not require pilots to consider the amount of celestial illumination, the amount of terrain lighting, or the presence of a visual horizon either enroute, or at the destination aerodrome. Pilots are also not required to consider the presence of high-altitude cloud along the planned route that may obscure celestial illumination.

In addition to the general requirements detailed in the AIP, Civil Aviation Regulation (CAR) 138 requires pilots to comply with any specific requirements detailed in aircraft and rotorcraft flight manuals. Some flight manuals contain specific night flight limitations. For example, the Transport Canada approved Bell 206B flight manual states:

'Night flight operation is limited to visual contact flight conditions. Orientation shall be maintained through visual reference to ground objects solely as a result of lights on the ground or adequate celestial illumination.'

The investigation noted that there was no specific night flight limitation in the Bell 407 flight manual.

Under certain conditions, external visual reference is not possible while conducting visual operations at night. These include operating over water or remote areas, in moonless conditions, and at times when the celestial horizon is obscured by cloud. From the available information, such conditions probably existed during the flight from Mackay to Hamilton Island on the night of the accident.

The investigation to determine the significant factors that contributed to the Bell 407 accident on 17 October 2003 is continuing.

Output text

Safety Recommendation

The Australian Transport Safety Bureau recommends that the Civil Aviation Safety Authority review the night visual flight requirements and promulgate information to pilots emphasising the importance, during flight planning, of considering whether:

* environmental conditions allow for aircraft orientation by visual reference alone;

* there is likely to be sufficient ground or natural lighting and flight visibility along the proposed route to provide visual reference to the ground and/or water during the flight; and

* they are capable of safely operating the aircraft should non-visual conditions be encountered.

Initial response
Date issued: 10 December 2003
Response from: Civil Aviation Safety Authority
Action status: Monitor
Response text:

CASA supports the issues raised in the Air Safety Recommendation and advises that the Authority is currently reviewing the night visual flight requirements with a view to emphasising to pilots, through its safety promotion activities, the importance of considering the above factors.
In response to the matters raised in the report, CASA wishes to bring the following to
the attention of the ATSB. The report, at the heading of 'Safety Deficiency' contains
the following:

'The AIP does not require pilots to consider the amount of external visual
reference that is likely to be available for a visual flight conducted at night. In particular, it does not require pilots to consider the amount of celestial illumination, the amount of terrain lighting, or the presence of a visual horizon either enroute, or at the destination aerodrome. Pilots are also not required to consider the presence of high-altitude cloud along the planned routes that may obscure celestial illumination.'

CASA believes that the ATSB may have overlooked the "ground lighting" requirement specified in subparagraph 4.2(d) of Section 20.18 of the Civil Aviation Orders.

Paragraph 4.2 states:
"A helicopter shall not be operated under the Instrument Flight Rules unless it is equipped with:
(a) the flight and navigation instruments specified in Appendixes VII, Vill, or IX to this section as applicable;
(b) any other instruments, indicators or equipment specified it the helicopter flight manual;
(c) the minimum lighting equipment specified in Appendix V to this section; and
(d) an approved automatic pilot, or automatic stabilisation system, for other than night VFR flights except that in the case of such flight which will involve more than 30 minutes fight over water or over land areas where aircraft altitude cannot be maintained by reference to ground lighting, an approved autostabilisation system or a two pilot crew shall be carried."

Further correspondence
Date issued: 21 December 2004
Response from: Civil Aviation Safety Authority
Response status: Monitor
Response text:

CASA does not agree that a review of night VFR requirements is necessary. Firstly, regulations specify that weather conditions of night VFR must be such that a planned flight can be conducted at a safe height clear of cloud. With respect to pilot competency, Civil Aviation Order (CAO) 40.2.2 specifies that the night VFR rating requires pilot be trained to control an aircraft solely by reference to instruments.

Any notion that celestial lighting and/or an apparent visible horizon are appropriate references for the control of an aircraft by night is misleading and dangerous and increases the probability of pilot disorientation.

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Further correspondence
Date issued: 27 January 2005
Response from: Civil Aviation Safety Authority
Response status: Closed - Not Accepted
Response text:

CASA expressed concern that the report appeared to attribute the cause of the accident to night VFR regulations rather than the shortcomings in recruitment, induction and training.
Moreover, CASA was troubled by the emphasis placed by ATSB on the need for specifying minimum ambient lighting requirements for night VFR operations. Reliance on ambient lighting at night rather than instruments for attitude reference is potentially hazardous due to the high risk of pilot disorientation.
CASA strongly believes that the requirements specified in Civil Aviation Order (CAO) 40.2.2 are adequate for night VFR operations. It is the responsibility of the operators to ensure that pilots meet the requirements specified for rating issue, especially those related to instrument flying. Therefore, CASA does not believe that a review of these requirements is necessary given that Australia already has the most comprehensive night VFR pilot qualification.

 
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Last update 03 April 2012