时间：2011-04-18 00:52来源：蓝天飞行翻译 作者：航空 点击：次
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FIG 10.2.6 “Clock” System for Identifying Positions Relative to the Nose of the Aircraft 4. When the helicopter approaches the scene, it will normally orbit at least one time as the flight crew observes the wind direction and obstacles that could interfere with the landing. This is often referred to as the “high reconnaissance” maneuver. f. Wind Direction and Touchdown Area 1.Determine from which direction the wind is blowing. Helicopters normally land and takeoff into the wind. 2.If contact can be established with the pilot, either directly or indirectly through the HEMS ground communications specialist, describe the wind in terms of the direction the wind is from and the speed. 3.Common natural sources of wind direction information are smoke, dust, vegetation movement, water streaks and waves. Flags, pennants, streamers can also be used. When describing the direction, use the compass direction from which the wind is blowing (example: from the North.West). 4.Wind speed can be measured by small hand.held measurement devices, or an observer’s estimate can be used to provide velocity information. The wind value should be reported in knots (nautical miles per hour). If unable to numerically measure wind speed, use TBL 10.2.3 to estimate velocity. Also, report if the wind conditions are gusty, or if the wind direction or velocity is variable or has changed recently. 5.If any obstacle(s) exist, insure their descrip-tion, position and approximate height are communicated to the pilot on the initial radio call. 10.2.12 Special Operations TBL 10.2.3 Table of Common References for Estimating Wind Velocity Wind (Knots) Wind Classification Appearance of Wind Effects On the Water On Land Less than 1 Calm Sea surface smooth and mirror.like Calm, smoke rises vertically 1.3 Light Air Scaly ripples, no foam crests Smoke drift indicates wind direction, wind vanes are still 4.6 Light Breeze Small wavelets, crests glassy, no breaking Wind felt on face, leaves rustle, vanes begin to move 7.10 Gentle Breeze Large wavelets, crests begin to break, scattered whitecaps Leaves and small twigs constantly moving, light flags extended 11.16 Moderate Breeze Small waves 1.4 ft. becoming longer, numerous whitecaps Dust, leaves, and loose paper lifted, small tree branches move 17.21 Fresh Breeze Moderate waves 4.8 ft. taking longer form, many whitecaps, some spray Small trees in leaf begin to sway 22.27 Strong Breeze Larger waves 8.13 ft., whitecaps common, more spray Larger tree branches moving, whistling in wires 28.33 Near Gale Sea heaps up, waves 13.20 ft., white foam streaks off breakers Whole trees moving, resistance felt walking against wind 34.40 Gale Moderately high (13.20 ft.) waves of greater length, edges of crests begin to break into spindrift, foam blown in streaks Whole trees in motion, resistance felt walking against wind 41.47 Strong Gale High waves (20 ft.), sea begins to roll, dense streaks of foam, spray may reduce visibility Slight structural damage occurs, slate blows off roofs 48.55 Storm Very high waves (20.30 ft.) with overhanging crests, sea white with densely blown foam, heavy rolling, lowered visibility Seldom experienced on land, trees broken or uprooted, “considerable structural damage” 56.63 Violent Storm Exceptionally high (30.45 ft.) waves, foam patches cover sea, visibility more reduced 64+ Hurricane Air filled with foam, waves over 45 ft., sea completely white with driving spray, visibility greatly reduced EXAMPLE. Wind from the South.East, estimated speed 15 knots. Wind shifted from North.East about fifteen minutes ago, and is gusty. Special Operations 10.2.13 g. Night LZs 1. There are several ways to light a night LZ: (a) Mark the touchdown area with five lights or road flares, one in each corner and one indicating the direction of the wind. See FIG 10.2.7. FIG 10.2.7 Recommended Lighting for Landing Zone Operations at Night NOTE. Road flares are an intense source of ignition and may be unsuitable or dangerous in certain conditions. In any case, they must be closely managed and firefighting equipment should be present when used. Other light sources are preferred, if available. (b)If chemical light sticks may be used, care should be taken to assure they are adequately secured against being dislodged by the helicopter’s rotor wash. (c)Another method of marking a LZ uses four emergency vehicles with their low beam headlights aimed toward the intended landing area. (d)A third method for marking a LZ uses two vehicles. Have the vehicles direct their headlight beams into the wind, crossing at the center of the LZ. (If fire/rescue personnel are available, the reflective stripes on their bunker gear will assist the pilot greatly.)2. At night, spotlights, flood lights and hand lights used to define the LZ are not to be pointed at the helicopter. However, they are helpful when pointed toward utility poles, trees or other hazards to the landing aircraft. White lights such as spotlights, flashbulbs and hi.beam headlights ruin the pilot’s night vision and temporarily blind him. Red lights, however, are very helpful in finding accident locations and do not affect the pilot’s night vision as significantly. 3. As in Day LZ operations, ensure radio contact is accomplished between ground and air, if possible. h. Ground Guide 1.When the helicopter is in sight, one person should assist the LZ Coordinator by guiding the helicopter into a safe landing area. In selecting an LZ Coordinator, recognize that medical personnel usually are very busy with the patient at this time. It is recommended that the LZ Coordinator be someone other than a medical responder, if possible. Eye protection should be worn. The ground guide should stand with his/her back to the wind and his/her arms raised over his/her head (flashlights in each hand for night operations.) |
