Source: This article was adapted from The
Essential Technical Rescue Field Operations Guide, 4th Edition, by Tom
Pendley of Desert Rescue Research in Glendale, Arizona. Copyright © 2011.All
Rights Reserved. Excerpted with Expressed Written Permission. To purchase a
copy of this handy, 196-page, spiral-bound, pocket-sized field guide, point
your Internet browser to www.DesertRescue.com or call 1.877.434.4781.
The "Landing Zone Safety" diagram posted here is wrong, and presents a potentially dangerous situational hazard. The tip path area directly in front of all rotary wing aircraft should always be listed as a "Danger" area for both approach and departure of personnel on foot in any situation. Main rotor hubs on a majority of helicopter designs often include a forward positive degree tilt directly designed into the hubs mount. This causes a forward degree lean of the M/R even while flat pitched, making the fore most area the lowest point (often capable of swooping down to a level of 4 feet for many airframes), while the aft most area is always the highest point the blades are from the ground. Therefore, the ONLY safe zones from both approach and departure of personnel on the ground will always remain the "3" and "9" O'Clock positions directly perpendicular to the aircraft's cabin doors, with a 20 degree forward, and 40 degree aft spread. This means that from the forward most point of the skids or front tire, to the aft most part of the cabin intersection with the frames transition section (or where the cabin doors open to when fully open) are the only safe zones - rising and falling terrain must also be taken into consideration. It is thus always safer to approach from the sides at a 90 degree angle, or slightly from the rear, diagonally towards the cabin, than from either the front forward of the tire or skids, or the rear aft of the cabin frame. The further forward you go, the greater risk of loosing your head to even your entire upper body - and YES, even wind can cause a tip path droop.
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