Project on Standards and Regulation regarding a Bird Strike
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- 2.1 An Impact-Force Equation
- 2.2 Costs Of Wildlife-Damage To Aircraft
- 2.2.1 Jet engines
- 2.2.2 Piston, turboprop and turboshaft engines
- 2.2.3 Windshields
- 2.2.4 Wing and tail structures
- 2.2.5 Landing gear
- 2.2.6 Other components
- 2.2.7 Delayed-effect damage
2 WILDLIFE-STRIKE COSTSOperating price within the aviation industries are very high, competition is fierce, and in most case income margins are small. If sources are to be dedicated to the reduction of aircraft damage as a result of bird and mammal-strikes, simplest a sound enterprise case will ensure the allocation of those finances. 2.1 An Impact-Force EquationThe fee of a wildlife strike is at once associated with the part of the plane broken and the value of the damage, which is decided by using the impact pressure created with the aid of the collision between the aircraft and bird or mammal. A precise effect-pressure calculation includes impact speed, bird weight, density, dimensions and configuration, in addition to angle of impact. Expressed in an equation, impact pressure is proportional to bird mass and the rectangular of impact pace. All forward-facing components of plane are prone to being struck with the aid of birds. Aircraft undersides and touchdown tools also are in chance of effect in the course of take-off and landing, when aircraft are at better pitch angles. Close to seventy five percent of pronounced bird moves, wherein altitude turned into stated, came about within 500 feet of the floor. Transport Canada records show that, in which phase of flight was mentioned, approximately 90 percent of wild strike strikes befell at some stage in the take-off and landing [3]. 2.2 Costs Of Wildlife-Damage To Aircraft
Now, we will see how birds strike effect on aircraft components: Three-quarters of bird strikes involve the wing or engines, but they can damage nearly any part of an airplane. 
Figure Percentage of bird strike in each part [4] 2.2.1 Jet enginesMost individual small birds struck by jet engines are killed by the blades of the primary level and pass through the interior of the engine without causing any considerable damage. A single strike by a medium-sized bird, and multiple strikes of small birds, frequently result in some engine damage. Blades in the first fan stage may be bent or deformed. Numerous blades may creak or break in the event of a more serious strike by single or multiple large birds. The broken blades can be ingested into the engine, damaging subsequent engine stages which leading to complete engine failure or destruction. In a few cases, this has led to an uncontained failure of the engine. Engine parts, expelled through the engine cowl, can also cause damage to other parts of the aircraft’s systems or structure [3]. 
Figure Broken jet engine by bird strike [5] Two conclusions come out from the increased use of large high-bypass ratio turbofan engines.
Jet engines are finely balanced exactness machines. Ingesting a bird, no matter how small, needs an inspection at the very least. Even minor cause to the first stage fan section can result in significant costs to repair or replace the broken fan blades. The cost to replace an engine often climbs to several million dollars. In this case, the aircraft is going to be service for a minimum of one day. 2.2.2 Piston, turboprop and turboshaft enginesThese engines are generally less susceptible to serious damage from bird strikes. The inlet areas are substantially smaller than those of turbofan engines, and the propeller or rotor blades provide some protection by deflecting bird debris away from engine intakes. Normally, mammal strikes to these types of engines do not directly result in engine damage. Broken propeller blades, however, will bring catastrophe. With an unbalanced load, the engine can be severely damaged and should become from its mounts. 2.2.3 WindshieldsThe results of windshield strikes vary from tiny bloody smears to large-scale shattering. In a number of cases, once complete penetration has occurred, bird remains and windshield pieces have caused injuries and even death to crew members. In piston-powered aircraft and helicopters, windshields are typically fabricated of a light weight Plexiglas material that is not certified to resist any significant impact from a bird strike. Even though these aircraft operate at lower speeds than jets, and impact forces of bird strikes are diminished, there are varied instances of shattered windshields and cockpit penetrations. Single-engine piston aircraft are somewhat less liable to windshield strikes due to the protection provided by the engine and propeller. In the case of helicopters, the very large windshield area poses high of a risk. In addition, helicopters frequently spend a higher proportion of their total flight time at low altitudes where large numbers of birds fly. Windshield replacement costs can be as low as $2,000 for general-aviation aircraft, and as high as $100,000 for a large jet aircraft [3]. Repair or replacement times will take a few hours to several days, depending on the damage to the surrounding airframe structure [6]. 
Figure the cracked canopy of an F-16 after a bird strike [7] 2.2.4 Wing and tail structuresA strike to the leading edge of the wing or tail elements can result in a dent or hole in the skin and probably torn or crumpled metal. If the bird is sufficiently heavy or dense, and the aircraft speed more enough, the animal might penetrate way enough into the aircraft structure to damage the spar and control cables or hydraulic elements. Several wing designs incorporate the use of lift augmentation devices, like flaps or slats, on either the leading or trailing edge of the wing. These too can be broken by a bird strike. Damage-repair costs can be negligible in the case of a small dent that requires dressing out, however staggering if vital damage occurs to crucial structures or systems [3]. 
Figure Bird strike damage aircraft wing [5] 2.2.5 Landing gearAt first look, aircraft landing gear seem to be very strong parts capable of absorbing significant loads throughout landing. However, closer examination shows that the most landing gear used on today’s aircraft include a variety of vulnerable components such as hydraulic lines, electrical cables, solenoids and micro-switches. Rarely does a bird strike lead to vital structural damage to the undercarriage. However, within the case of mammal strikes, particularly deer, undercarriage damage is severe. Repair costs to undercarriages vary from a few hundred dollars for the replacement of broken hydraulic lines and small switches to over $100,000 for structural damage to the main landing-gear parts [3]. 
Figure Bird strike with landing gear [7] 2.2.6 Other componentsMany alternative aircraft components are damage with varying repair costs and times as a results of bird and mammal strikes. These other components include radomes, landing lights and pitot tubes. Replacement prices for these parts will be thousands of dollars, and repair times vary between several hours and several days [6]. 2.2.7 Delayed-effect damageOne of the more sinister results of bird strikes is injury that is not immediately apparent or detected. There are unit documented cases within which aircraft engines struck by birds after subsequently failed on later flights, despite basic visual inspections that detected no injury. Frequently, damage is not detected till the aircraft undergoes periodic review, and non-destructive testing is disbursed on disassembled aircraft components [6]. Directory: home home -> 0 1 Integer Linear Programs home -> Math 4630/5630 Homework 4 Solutions Problem Solving ip home -> Getting To Outcomes® in Services for Homeless Veterans 10 Steps for Achieving Accountability home -> Tiger Leaps Progress Update from Tenafly High School March 28, 2012 English home -> Материалы для подготовки к устному экзамену по английскому языку home -> Gregory D. Bothun as of 2013 University of Oregon Department of Physics home -> Peggy schaller saisir le désordre : Expressions littéraires de la catastrophe; modalités et enjeux de sa verbalisation home -> The Writings of home -> Eine Bibliographie MÜnchen 2009 home -> T. R. Berkshire Notes and Drafts for History of the College Download 150.39 Kb. Share with your friends:
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