RESCUE AND EVACUATION - Medicine for Mountaineering and Other Wilderness Activities - page 89

largeareaofsnowifonskis,oralargebodyofwater—usuallyalake—ifonfloats.Thepi-
lot must know the altitude, slope, and nature of the surface—especially if it is uneven or if
softsnowispresent that maycause askitostick—and alsomustknowaboutanyobstacles
ontheapproachortakeoff.Althoughhelicopterscanlandandtakeoffvertically,aroutefor
gradual descent and takeoff is safer. This is usually considered two routes—one for ingress
andanotherforegress—althoughhelicopterscanoftenturn180degreeswhilestillnearthe
ground and follow the same path for landing and takeoff. The larger the landing zone, the
safer it is. No objects, such as shrubs or tree stumps, should be sticking up, and all loose
objects must be secured so they do not get blown about and become hazards. Helicopter
pilotsalsoneedtoknowifthesurfaceiscoveredwithloosesnow,gravel,ordustthatcould
limit visibility on takeoff or landing when blown up by rotor wash.
Airplane and helicopter pilots need to know the weather conditions at the landing zone,
including visibility, temperature, and wind speed and direction. Ideally, at least one radio
should be available for ground-to-air communications, but signals can be used. A visible
indicatorofthewindspeedanddirectionisessentialandcanbeabrightlycoloredarticleof
clothing, a flare, or a smoke grenade. (Smoke from a fire is hazardous because the burning
material can be spread about by rotor or propeller wash.)
Marking the landing zone is helpful, particularly on snow. Dark-colored garbage bags
filled with snow or rocks give the pilot a visual reference that otherwise would be lacking.
Some pilots throw these out of the airplane onto the snow on a pass before landing. Any
object used to mark the landing zone or give wind direction must be well secured or heavy
enough not to blow about in propeller wash or rotor downwash.
All personnel and equipment should be out of the landing zone, unless the terrain re-
quires that a helicopter land right next to a rescue team. The team must crouch and not
move while the helicopter lands. No loose equipment or clothing should be allowed in the
landing zone. If the landing zone has gravel, dust, or loose snow, anyone nearby should
wear eye protection and face away from the helicopter during landing and takeoff. In an
emergency,puttingahandinfrontoftheeyesandsquintinghelpssomewhat.Awindbreak-
er with a hood is also helpful.
Hot loading and unloading (engine running and rotors turning) is more hazardous but
may be necessary. During hot loading the tail rotor may be nearly invisible.
People on the ground must approach or leave helicopters only from the front and sides
(except for rear-loading Chinook helicopters) and only after a signal or radioed permission
fromthepilotoracrewmember.Theymuststayinthepilot'slineofsightduringtheentire
process. If the helicopter is on a slope, ground personnel should approach and leave from
the downhill side of the helicopter, which helps to maintain a safe distance below the rotor
blades. If circling around the helicopter is necessary, it should always be done around the
front.