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Old 1st Jul 2008, 13:36
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Mars
 
Join Date: Jun 2003
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...and I guess we are now back to the issue of culture.

If human factors teaches us one thing it is that, whilst the pilot is (almost always) at the controls during the accident sequence, he/she is rarely completely to blame for the accident. Shappell and Wiegmann would have us believe that, amongst the precursors to any accident reside: the organisational influences; unsafe surpervision; preconditions for unsafe acts; and the unsafe acts themselves.

We have no knowledge of the causes of this accident but that should not stop us from discussing one which has cropped up in the past; the potential for error that accompanies a straight-in approach to the helideck (which fits into "Substandard Practices of Operators" - one of the preconditions for unsafe acts). By the very nature of the cockpit layout, the field of view (FOV) of a helicopter - that is the visibility out of the front of the cockpit - will always be obstructed by the instrument panel. During the decelerative landing manoeuvre, this will be made worse by the nose-up attitude (especially in the S76). To compound this combination of factors, most helidecks will rarely be of more than 1D (where D is the maximum length of the helicopter with the rotors turning).

The combination of paucity of view coupled with a small landing surface and a lack of peripheral visual cues, usually results - in the straight-in approach - in an arrival conducted from memory. Because the margins for error are substantially removed in this manoeuvre, it can lead to the tail getting very close and, in some cases, striking the deck surrounds.

Much better that such a manoeuvre is avoided and the landing taken with the FOV that is free of obstructions - i.e. the oblique and side window. Any overcooking of the approach can be rectified by a go-around conducted straight ahead (which also works in the case of an engine-failure on finals - both for a twin and a single).

Mars
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