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Many pilots drop dye balloons en route so they can find their way back. Others fly low enough to create a disturbance in the snow surface with their downwash, with the obvious dangers.
Landing
Landing Sites should be selected with a view to pulling out of a resulting snow cloud if necessary. That is, you need escapes.
As with landing on mountains, there are various schools of thought about landing on snow. One is the zero/zero method (zero speed, zero height), for which you carry out a normal approach, using a constant attitude with minimum changes, losing translational lift at the last minute. Aim to keep going forward and downward until a few inches above the snow, so the downwash is always behind you, using the aircraft shadow, a smoke grenade or the landing light to provide texture to the surface. Even a fuel drum makes a good visual reference. Another good trick is to use a dark-painted stake with a flag on it – the flag makes the stake behave like a dart, so the point goes into the snow, and acts as a wind indicator afterwards. Do not hover, don’t go beyond the marker, and try to land just as the snow cloud develops.
When you commit yourself, however, you will need to check the firmness of the surface, which is not usually a problem at a camp or something, as the ground crew will have done this for you. The danger lies when you're going to an unchecked site for the first time. Touch down lightly without delay, treating it as a sloping ground landing, as the vibration of the helicopter itself can cause ice to crack. Any form of load spreading is a good idea if you can take advantage of it, like landing on a log pad, although your landing gear will largely determine what you can use. As an example, a fully loaded JetRanger on floats weighs 133 lbs per sq foot, whilst one on skids and bear paws is nearer 400. Whatever you choose, it needs to be twice as thick if you intend staying overnight.
Another method, possibly better for beginners, is to come to a high hover (with escapes) to allow the downwash to clear the snow, then lower the machine slowly and smoothly, so you need to be wary if you’re heavy. Still another is a really shallow approach on the edge of translational lift, to slowly move forward onto the site with your skids on the ground.
Once landed, bounce the skids a little to see if there's a crust, although you should be careful with the Astar as too much downward force on the blades could cause the head to crack, aside from pushing the belly panel up into the controls (watch out for the swinging hook, too, which could cause loss of fuel). The belly landing light is a great snow scoop which could affect the controls as well.
Keep your RPM to flying levels until you're sure you're on firm ground.
Always keep the helicopter light on the skids until passengers are clear, regardless of the surface. Don’t let anyone out till you’re happy.
The colour of ice can be a good clue as to its suitability. White or blue is the thickest, and therefore safest, whereas black ice may have running water underneath and will be quite thin (for this reason, avoid inflows or outflows of streams or rivers). Granular, dirty looking ice is melting. Large puddles or sheets of water are also a dead giveaway. However, ice is never really safe – it doesn’t matter how many heavy water trucks the customer may have parked there that week, helicopters vibrate a lot more than trucks do or, more particularly, in a different way, and the hole punched through for the hosepipe has already weakened the structure. Also, however thick they tell you the ice is, you have no way of knowing whether it is actually supported by water underneath (the level may have dropped), or whether any running water has eroded the under surface. Neither do you know whether any snow on top has shielded the ice from the cold, or whether the Sun’s rays have reacted with bare ice to act as a lens and create temperatures dangerously close to a thaw, during which ice several feet thick can often become composed of long vertical needles, known as candle ice. Always try and land somewhere else first.
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