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Saturday, October 19, 2019

The Effects of Microburst on Small Aircraft Research Paper

The Effects of Microburst on Small Aircraft - Research Paper Example In extreme dry conditions when moist convection is just barely possible, cumulus clouds with very high bases form above the surface; below this high-based cloud layer there is a deep, dry adiabatic layer of microburst. In extreme wet conditions a deep, nearly saturated layer with a nearly moist pseudoadiabatic lapse rate forms that is topped by an elevated dry layer which is a cause of microburst. In case of dry microburst the rain falls below the cloud base mixes with dry air from where it begins to evaporate and this evaporation process cools the air. The cool air descends and accelerates as it approaches the ground from where it spreads in all directions and the divergence of wind is the sign of a microburst. The wet microburst is accompanied by heavy rainfall at the surface which are warmer then the environment. This downburst pushes the downward acceleration of parcels that cause negative buoyancy which tends to drive dry microburst. Wind shear is the difference in wind speed and direction over a short distance in the atmosphere. The extent and suddenness of a microburst accompanied with low-level wind shears are a cause of many fatal aircraft crashes; particularly they affect in landing and take-off phases. The microburst is recorded to last no more then 15 minutes from the time they strike on the ground. During the first 5 minutes the horizontal wind continues to rise with maximum intensity lasting 2-4 minutes Sometimes microburst are concentrated into a line structure, and under these conditions, activity may continue for as long as an hour. Once microburst activity starts, multiple microbursts in the same general area are not uncommon and should be expected. Hazards to flight The strong, concentrated winds along with rainfall and thunderstorms have caused fatal aircraft accidents. (Downbursts, Fujita, 1985). As the aircraft enters in the way of microburst, it encounters an increased head wind. This head wind lifts the aircraft, the pilots reacts to correct the aircraft approach angle by reducing engine power. The aircraft then passes into the vertically descending microburst core which results in a loss of lift and altitude. Immediately the aircraft crosses into a region of tail winds (the wind which blows in the direction of the object), which reduces the relative airspeed of the aircraft and further decreases lift, causing the aircraft to lose more altitude. Because the aircraft is now flying on reduced power, it is vulnerable to sudden losses of airspeed and altitude. The microburst is often of right scale and intensity to crash an aircraft which is evident by a number of accidents associated with microburst over about a decade. The crew and passengers all become victims to the crash and give their lives. There are a large number of human losses especially if microburst attacks at the time of take-off and landing. Predicting Microburst Microburst has always been a challenge for safety issues regarding the aircraft and small business jets. Its prediction, detection and avoidance are an issue of big concern for aviation authority. The pilots are unable to maintain the balance of strong winds and historically this has plagued the entire civil aircraft types including large commercial transports, regional airliners, business jets, and small personal-owner general

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