acamedic help needed

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[FONT=&quot]Discuss briefly some of the main causes of aircraft accidents in rough order of priority.




thank you
[/FONT]
 
hijack
pilot stupid
landing gear messed up
gas leak
too much gas
 
pilot stupid = CFIT lolz ... I love that one
 
I need more ... and something more evidential
 
There are many different reasons a plane crash may occur:
  • Pilot Errors - Pilots are responsible for transporting the plane's passengers from one destination to another. Pilots have a duty to follow air safety rules that have been outlined and created to better ensure the safety of everyone on board or else risk an aircraft accident.
  • Faulty Equipment - Faulty equipment, or even poorly maintained equipment can fail and cause an airplane to crash.
  • Violating FAA regulations - FAA laws exist to protect everyone using air travel. Violations of FAA regulations can endanger the safety of everybody in the air.
  • Structural or design problems with an aircraft .
  • Flight service station employee negligence .
  • Federal air traffic controllers' negligence .
  • Third party's carrier selection negligence .
  • Maintenance or repair of the aircraft or component negligence .
  • Fueling the aircraft negligence
you do not like using gogle yes??
 
need some specific ... stat, and other stuff ... anyway, thanks...
 
weather
old model plane lack repair
alein
UFO
overweigh


I'm agree that the main cause is gravity, for sure!:D
 
Bird strike

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F-16 canopy after a bird strike


A bird strike (sometimes birdstrike, bird hit, or BASH [bird aircraft strike hazard]) in aviation, is a collision between an airborne animal (most often a bird, but also sometimes another species) and a man made vehicle, especially aircraft. It is a common threat to aircraft safety and has caused a number of fatal accidents.
Contents

[hide]
[edit] Event description

Bird strikes happen most often during take off or landing, or during low altitude flight. However, bird strikes have also been reported at high altitudes, some as high as 6000 to 9000 meters above ground level. The majority of aircraft - bird collisions occur near or on airports (90%, according to the ICAO) during takeoff, landing and associated phases. According to the FAA wildlife hazard management manual for 2005, less than 8% of strikes occur above 900 meters and 61% occur at less than 30 m (100 feet).

A hawk stuck in the nosecone of a C-130



View of fan blades of JT8D Jet engine after a bird strike.


The point of impact is usually any forward-facing edge of the vehicle.
Jet engine ingestion is extremely serious due to the rotation speed of the engine fan and engine design. As the bird strikes a fan blade, that blade can be displaced into another blade and so forth, causing a cascading failure. Jet engines are particularly vulnerable during the takeoff phase when the engine is turning at very high speed.
In general, the force of the impact on an aircraft depends on the weight of the animal and the speed difference and direction at the impact. The energy of the impact increases with the square of the speed difference. Hence a low-speed impact of a small bird on a car windshield causes relatively little damage. High speed impacts, as with jet aircraft, can cause considerable damage and even catastrophic failure to the vehicle. However, according to the FAA only 15% of strikes (ICAO 11%) actually result in damage to the aircraft. The impact of a 5 kg (12 pound) bird at 240 km/h (150 mph) equals that of a 1/2 ton (1000 pound) weight dropped from a height of 3 meters (10 feet).
Bird strikes can damage vehicle components, or injure passengers. Flocks of birds are especially dangerous, and can lead to multiple strikes, and damage, within a very brief period. Depending on the damage, aircraft at low altitudes or during take off and landing often cannot recover in time and crash.
In the USA, remains of the bird, usually a bloody goo called snarge, are sent to the Smithsonian Institution's Feather Identification Laboratory to determine the species. [1] One flying organization with a larger than usual birdstrike risk is the Israeli Air Force, as Israel is on a major spring and autumn long-distance bird migration route.

[edit] Species

The animals most frequently involved in bird strikes are large birds with big populations, with geese and gulls causing most serious incidents. In the US reported strikes are divided between waterfowl (32%), gulls (28%), and raptors (17%) (Data from the BSC USA). The Smithsonian Institution's Feather Identification Laboratory has identified turkey vultures as the most damaging birds, followed by Canada geese and white pelicans, all very large birds. In terms of frequency, the laboratory most commonly finds Mourning Doves and Horned Larks involved in the strike. The largest numbers of strikes happen during the spring and fall migrations. Striking large land-bound animals, such as deer, can also be a problem to aircraft during take off and landing, and over 650 civil aircraft collisions with deer were reported in the U.S. between 1990 and 2004.

Deer entangled in a landing gear


Strangely enough, vehicle-animal air collisions also sometimes include species that cannot fly. The Smithsonian Institution's Feather Identification Laboratory has identified frogs, turtles, and snakes as the animal in the "bird" strike. On one occasion they identified a cat at high altitude and on another a rabbit at a height of 550 metres (1800 feet).[1]
The most likely explanation for this incongruity is that the animal identified had been either eaten or carried aloft by a bird of prey, though there are also meteorological explanations, such as raining animals.

[edit] Countermeasures

There are three basic approaches to reduce the effect of bird strikes. The vehicles can be designed to be more bird resistant, the birds can be moved out of the way of the vehicle, or the vehicle can be moved out of the way of the birds.

[edit] Vehicle design


The ICE 3 has been hit by a bird while operating at high-speed.


Most large commercial jet engines include design features that ensure they can safely shut-down after "ingesting" a bird weighing up to 1.8 kg (4 lb). However, this is a 'stand alone' requirement, i.e., the engine must pass the test, not the aircraft. Multiple strikes on twin engine jet aircraft are very serious events. Multiple or large strikes require emergency action to control damage.
Modern jet aircraft structures must be able to withstand one four pound bird collision; the empennage (tail) must withstand one 8 pound bird collision. Cockpit windows on jet aircraft must be able to withstand one 4 pound bird collision without yielding or spawlding.
Given the increasing numbers of large flocking birds whose average weight is in excess of these certification numbers, aircraft/engine design mitigation is a very modest contribution to safety.
At first bird strike testing by manufacturers involved firing a bird carcass from a gas cannon and sabot system into the tested unit. The carcass was soon replaced with suitable density blocks, often gelatin, to ease testing. Currently testing is mainly conducted with computer simulation, although final testing usually involves some physical experiments. See birdstrike simulator for details.

[edit] Bird management


A UH-60 Black Hawk after a collision with a type of crane, and subsequent failure of the windshield


To reduce birdstrikes on takeoff and landing, airports are required to engage in bird management and control. This includes changes to habitat around the airport to reduc eand eliminate its attractiveness to birds.[1] Vegetation which produces seeds, grasses which are favored by geese, manmade food, a favorite of gulls, all should be removed from the airport area. Cmdr. B Pride {USNCB} has made recommendation to install artificial turf products in and around runways to minimize roosting and feeding areas for birds and small animals that become prey for larger fowl such as eagles and owls. Trees and tall structures which serve as roosts at night for flocking birds or perches for raptors should be removed or modified to discourage bird use.[2]
Other approaches try to scare away the birds using frightening devices, for example sounds, lights, pyrotechnics, radio-controlled airplanes, decoy animals/corpses, lasers, degs etc.[2]Firearms are also occasionally employed.
TNO a Dutch R&D Institute has developed the successful ROBIN (Radar Observation of Bird Intensity) for the Royal Netherlands Airforce at the end of the eighties of the last century, a near real-time monitoring system for flight movements of birds. At this moment TNO has developed a third version of ROBIN, utilizing the latest technologies. ROBIN identifies flocks of birds within the signals of large radar systems. This information is used to give airforce pilots timely warning during landing and take-off. Years of observation of bird migration with ROBIN has also provided a better insight into bird migration behaviour, which in turn has had a positive influence on the possibility to avert collisions with birds, and therefore on flight safety.
Collisions decreased Ever since the implementation of the ROBIN system at the Royal Netherlands Airforce the number of collisions between birds and aircraft in the vicinity of military airbases has decreased by more than 50%.

A successful approach in recent years has been the utilization of dogs, including german sheperds, english pointers and border collies, to scare away birds and wildlife.[citation needed] Another alternative is bird capture and relocation.
Falcons are sometimes used to harass the bird population, as for example on John F. Kennedy International Airport.[1] At Manchester Airport in England the usual type of falcon used for this is a peregrine falcon/lanner falcon hybrid, as its habitual flight range is about the right size to cover the airport and not also much irrelevant land around.
An airport in New Zealand uses electrified mats to reduce the number of worms that attracted large numbers of sea gulls.[1]

[edit] Flight path


A UH-60 after a collision with a type of crane, and subsequent failure of the windshield as seen from the inside.


Pilots have very little training in wildlife avoidance nor is training required by any regulatory agency. However, they should not takeoff or land in the presence of wildlife, avoid migratory routes [1], wildlife reserves, estuaries and other sites where birds may congregate. When operating in the presence of bird flocks, pilots should seek to climb above 3,000 feet as rapidly as possible as most birdstrikes occur below 3,000 feet.
The US Military Aviation Hazard Advisory System uses a Bird Avoidance Model[3] based on data from the Smithsonian Institution, historical patterns of bird strikes and radar tracking of bird activity.[1] This model has been extremely successful. Prior to flight USAF pilots check for bird activity on their proposed low level route or bombing range. If bird activity is forecast to be high, the route is changed to one of lower threat. In the first year this BAM model was required as a preflight tool, the USAF Air Combat Command experienced a 70% drop in birdstrikes to its mission aircraft.

[edit] Incidents

The Federal Aviation Administration estimates the problem costs US aviation 600 million dollars annually and has resulted in over 200 worldwide deaths since 1988. In the United Kingdom the Central Science Laboratory estimates that, worldwide, the cost of birdstrikes to airlines is around US$1.2 billion annually. This cost includes direct repair cost and lost revenue opportunities while the damaged aircraft is out of service. Estimating that 80% of bird strikes are unreported, there were 4,300 bird strikes listed by the United States Air Force and 5,900 by US civil aircraft in 2003.
The first reported bird strike was by Orville Wright in 1905, and according to their diaries Orville … flew 4,751 meters in 4 minutes 45 seconds, four complete circles. Twice passed over fence into Beard's cornfield. Chased flock of birds for two rounds and killed one which fell on top of the upper surface and after a time fell off when swinging a sharp curve.
The first recorded bird strike fatality was reported in 1912 when aero-pioneer Cal Rodgers collided with a gull which became jammed in his aircraft controls. He crashed at Long Beach, California, was pinned under the wreckage and drowned.
The greatest loss of life directly linked to a bird strike was on October 4, 1960, when Eastern Air Lines Flight 375, a Lockheed L-188 Electra flying from Boston, flew through a flock of common starlings during take off, damaging all four engines. The plane crashed shortly after take-off into Boston harbor, with 62 fatalities. Subsequently, minimum bird ingestion standards for jet engines were developed by the FAA.
The Space Shuttle Discovery also hit a bird during take-off on July 26, 2005, although the collision occurred early during take off and at low speeds, with no obvious damage to the shuttle. It is not clear if the bird survived. NASA also lost an astronaut, Theodore Freeman, to a bird strike, he was killed when a goose shattered the plexiglass cockpit of his T-38, resulting in shards being ingested by the engines leading to a fatal crash.
Aircraft continue to be lost on a routine basis to birdstrikes. In the fall of 2006 the USAF lost a twin engine T-38 trainer to a bird strike (ducks) and in the October 2007 the US Navy lost a T-45 jet trainer in a collision with a bird.
In the summer of 2007 Delta Air Lines suffered serious incident in Rome, Italy, as one of its B-767 aircraft, on takeoff, ingested yellow legged gulls into both engines. Although the aircraft returned to Rome safely, both engines were damaged and had to be changed. United Air Lines suffered a twin engine bird ingestion by a B-767 on departure from Chicago's O'Hare Field in the spring of 2007. One engine caught fire and bird remains were found in the other engine.

[edit] In popular culture
  • In the film Indiana Jones and the Last Crusade, while remembering a quotation by Charlemagne, the title character's father downs an attacking aircraft by scaring a flock of birds into its flightpath with his umbrella.
  • Among Japanese aviation engineers and pilots, birds sucked into a jet engine are referred as yakitori after the popular dish.[citation needed]
  • In the film Thirteen Days, Navy pilot William Ecker called the obvious damages on his aircraft "bird strikes" after the first low-level reconnaissance flight over Cuba in order to avoid international conflict as he was fired upon.
[edit] References
  1. <LI id=_note-wired>^ a b c d e f Wired Magazine: Bird Plus Plane Equals Snarge <LI id=_note-ibc>^ a b http://www.int-birdstrike.org/Standards_for_Aerodrome_bird_wildlife%20control.pdf
  2. ^ US Bird avoidance model
[edit] See also
[edit] External links
 
1.没空姐。
2.空姐太恶心。
3.空姐太漂亮。
4.地勤不够勤。
5.飞得不如导弹快。
6.不是名牌飞机。
7.Zeus mana太多。
。。。。。。
 
Released Russian revenge killer returns from Switzerland


10:39 | 13/ 11/ 2007
MOSCOW, November 13 (RIA Novosti) - A Russian national jailed in Switzerland for killing an air traffic controller he blamed for the death of his family arrived in Moscow on Tuesday following his early release.
Vitaly Kaloyev lost his wife and two children in an air crash in 2002. In February 2004, he stabbed to death the only air traffic controller on duty at the time of the accident. Kaloyev was sentenced to eight years in 2005 but Switzerland's top court ruled on Thursday to release him ahead of time.
On arriving at Moscow's Domodedovo airport, Kaloyev was greeted by slogans including: "You are a real human." The 51-year-old architect has received substantial public sympathy in Russia since his conviction.
He thanked President Vladimir Putin and the Russian people for their support. "When in prison, I did not feel like I was away from my country."
On the night of July 1, 2002, a Russian Bashkirian Airlines passenger plane collided with a DHL cargo aircraft over southern Germany in airspace controlled by Swiss air traffic control company Skyguide, killing 71 people, including 45 children.
Earlier this year four employees of Skyguide were found guilty of criminal negligence leading to the crash.
Kaloyev's sentence was cut to five years and three months, and he was released by Swiss authorities on Monday due to good behavior, having served more than two-thirds of his sentence. Two of the court's five judges contested the early release.
 
1. Loss of control (38) (28%)
2. CFIT (36) (26%)
3. Other (14) (10%)
4. Landing (9) (7%)
5. Hijack (8) (6%)
6. Fuel exhaustion (7) (5%)
 
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