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Water landing

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A water landing is, in the broadest sense, any landing on a body of water. All waterfowl, those seabirds capable of flight, and some human-built vehicles are capable of landing in water as a matter of course.

The phrase "water landing" is also used as a euphemism for crash-landing into water in an aircraft not designed for the purpose. The National Transportation Safety Board of the United States government defines "ditching" in its aviation accident coding manual as "a planned event in which a flight crew knowingly makes a controlled emergency landing in water. (Excludes float plane landings in normal water landing areas.)"[2] Such water landings are extremely rare for commercial passenger airlines.

By design

Apollo 15 capsule descends under two of three parachutes

Seaplanes, flying boats, and amphibious aircraft are designed to take off and land on water. Landing can be supported by a hull-shaped fuselage and/or pontoons. The availability of a long effective runway was historically important on lifting size restrictions on aircraft, and their freedom from constructed strips remains useful for transportation to lakes and other remote areas. The ability to loiter on water is also important for marine rescue operations and fire fighting. One disadvantage of water landing is that it is dangerous in the presence of waves. Furthermore, the necessary equipment compromises the craft's aerodynamic efficiency and speed.

Early manned spacecraft launched by the United States were designed to land in water by the splashdown method. The craft would parachute into the water, which acted as a cushion to bring the craft to a stop; the impacts were violent but survivable. Landing over water rather than land made braking rockets unnecessary, but its disadvantages included difficult retrieval and the danger of drowning. The modern Space Shuttle lands on a runway instead.

In distress

Although extremely uncommon in commercial passenger travel, small aircraft ditchings are common occurrences. According to the United States Coast Guard, including helicopters and fixed-wing aircraft, between military, air carrier, corporate, and general aviation, there is one ditching every day in U.S. waters alone.[1][dubiousdiscuss]

General aviation

General aviation includes all fields of aviation outside of military or scheduled (commercial) flights. This classification includes small aircraft, e.g., training aircraft, airships, gliders, helicopters, and corporate aircraft, including business jets and other for-hire operations. General aviation has the highest accident and incident rate in aviation, with 16 deaths per million flight hours, compared to 0.74 deaths per million flight hours for commercial flights (North America and Europe) [3].

Commercial aircraft

US Airways Flight 1549, ditched in the Hudson River in 2009 with all passengers surviving

The FAA does not require commercial pilots to train to ditch, regulating instead the distance a plane can stray from an airfield.[1]

Nevertheless, all airliners are equipped with flotation devices in case of water landings. According to FAA regulations, aircraft that travel no further than 50 nautical miles from shore are only required to be equipped with flotation seat cushions. Aircraft that travel no further than 162 nautical miles from shore are required to be equipped with life vests for all passengers. If an aircraft travels further than 162 nautical miles from shore it must be equipped with life vests for all passengers, and life rafts/raft evacuation slides.

While there have been several 'successful' (survivable) water landings by narrow-body and propeller-driven airliners, few commercial jets have ever touched down 'perfectly' on water. There has been a good deal of popular controversy over the efficacy of life vests and rafts. For example, Ralph Nader's Aviation Consumer Action Project had been quoted as claiming (though not offering proof) that a wide body jet would “shatter like a raw egg dropped on pavement, killing most if not all passengers on impact, even in calm seas with well-trained pilots and good landing trajectories."[1]

Also, in December 2002, The Economist had quoted an expert as claiming that "No large airliner has ever made an emergency landing on water" in an article that goes on to charge, "So the life jackets ... have little purpose other than to make passengers feel better."[2][3] This claim was repeated in The Economist in September 2006 in an article which reported that "in the history of aviation the number of wide-bodied aircraft that have made successful landings on water is zero."[4]

However, on January 15, 2009, US Airways Flight 1549, an Airbus A320 narrow-body jet, successfully landed in the Hudson River adjacent to Manhattan in New York City. All on board survived, showing that inflatable slide-rafts and life jackets can sometimes serve their purposes, although photographs from the incident show that very few, if any, passengers were wearing life jackets. After take-off from La Guardia, initial reports cite dual engine failure due to bird strikes at a low altitude. Pilot Chesley B. "Sully" Sullenberger was able to cross the Bronx in a slow turn to the south-west, pass over the George Washington Bridge and ditch the plane in the Hudson River. The left engine broke away on contact with the river.[5] All 155 passengers and crew survived with only one major injury and 77 minor injuries[6][7], in part because the plane came to a halt adjacent to the passenger ferry route between NYC and New Jersey.

Survival rates of passenger plane water ditchings

In all cases where a passenger plane has undergone an intentional water landing or ditching, some or all of the occupants have survived. Examples of water landings in which passengers survived after a planned and intentional water landing after an in-flight emergency are:

  • On 15 January 2009, US Airways Flight 1549 (an Airbus A320) successfully ditched into the Hudson River in New York City, after reports of multiple bird strikes. All of the 155 passengers and crew aboard escaped and were rescued by passenger ferries and day-cruise boats, in spite of freezing temperatures (the ditching occurred near the Circle Line and NY Waterway piers in midtown Manhattan).[8] All 155 passengers and crew survived.The survival rate was 100%.
  • On 23 November 1996, Ethiopian Airlines Flight 961 (a Boeing 767-260ER), ditched in the Indian Ocean near Comoros after running out of fuel, killing 125 of the 175 passengers and crew on board. The crash landing followed a hijacking of the aircraft and reports indicate that there was fighting between flight crew and the hijackers at the time of impact. Although most passengers survived the initial impact, many died after inflating their life vests while still inside the fuselage, prohibiting their escape from the sinking wreckage. The survival rate was 29%.
  • On 21 August 1963, an Aeroflot Tupolev Tu-124 ditched into the Neva River after running out of fuel. The aircraft floated and was towed to shore by a tugboat which it had nearly hit as it came down on the water. The tug rushed to the floating aircraft and pulled it with its passengers near to the shore where the passengers disembarked onto the tug; all 52 on board escaped without injuries.[12] The survival rate was 100%.
  • On Oct. 4, 1960, 62 people died when Eastern Air Lines Flight 375 (Lockheed Electra four-engine turbo-prop) plunged wing-first into Boston Harbor after flying shortly after takeoff into a flock of starlings. Three engines lost power, and the plane stalled and spun, crashed into water 200 yards offshore, and broke in half. Nine of the 10 survivors had serious injuries. It was the first commercial airline crash in Logan Airport's history, the deadliest air disaster in New England history at the time, and it remains the most deadly crash in US history involving a bird strike.[13] The survival rate was 14%.
  • In April 1956, Northwest Orient Airlines Flight 2 (also a Boeing 377) ditched into Puget Sound after the flight engineer forgot to close the cowl gills on the plane's engines. All aboard escaped the aircraft after a textbook landing, but four passengers and one flight attendant succumbed either to drowning or to hypothermia before being rescued. The survival rate was 87%.

Planes landing on water for other reasons

Aircraft also sometimes end up in water by running off the end of runways, landing in water short of the end of a runway, or even forcibly flown into the water during homicidal events. While such incidents are just as rare as water ditching and are not quite water landings, the passengers do find themselves swimming. Twice at LaGuardia Airport, aircraft have rolled into the East River.

  • On 23 November 1996, Ethiopian 961 (a Boeing 767-200ER) ditched in shallow water 500 meters from land after being hijacked and running out of fuel. Unable to operate flaps, it impacted at high speed, dragging its left wingtip before tumbling and breaking into three pieces. The panicking hijackers were fighting the pilots for the control of the plane at the time of the impact, which caused the plane to roll just before hitting the water, and the subsequent wingtip hitting the water and breakup are a result of this struggle in the cockpit. Of 175 on board, 52 survived. Some passengers were killed on impact or trapped in the cabin when they inflated their life vests before exiting. Most of the survivors were found hanging onto a section of the fuselage that remained floating. The survival rate was 30%.
  • On 12 September 1993, while landing in poor weather conditions at Papeete Faaa airport, Tahiti, an Air France Boeing 747 registered F-GITA hydroplaned, overshot the runway and ended in a lagoon. All 272 passengers and crew evacuated successfully, even though the engines were still running and there was a risk of ingestion.[17] The survival rate was 100%.
  • In 1982, Air Florida Flight 90 went down in the Potomac river after taking off from Washington National Airport. Only 6 out of 79 passengers and crew survived the initial crash, with one of the survivors eventually drowning after helping others to safety.
  • On 7 August 1980, a Tupolev 154B-1 operated by Tarom Romanian Airlines ditched in the water, 300m short of the runway at Nouadhibou Airport (NDB/GQPP), Mauritania. 1 passenger out of 168 passengers and crew died. The survival rate was 99%.

Crashing

There is a distinction between a controlled ditching and simply crashing (not even crash-landing) into the water; the latter is capable of killing everyone upon impact and disintegrating the plane. For example:

On a smaller scale, John F. Kennedy, Jr. and his two passengers died in a water crash. As pilot and columnist Patrick Smith comments, these crashes tend to be more memorable than controlled water landings, perhaps fueling the public's suspicions of the survivability of aircraft that hit water.[22]

See also

References

  1. ^ a b c Brus, Michael (1999). "In the Event of a Water Landing". Slate. Washingtonpost.Newsweek Interactive. Retrieved 2006-06-26.
  2. ^ Unidentified (2002). "Help! There's nobody in the cockpit". The Economist. Retrieved 2006-06-26. {{cite journal}}: Unknown parameter |month= ignored (help)
  3. ^ Smith, Patrick (2003). "Ask the pilot #24: Can we stop bombs in our baggage?". Salon.com. Retrieved 2006-06-28.
  4. ^ Unidentified (2006). "Welcome aboard". The Economist. {{cite journal}}: Unknown parameter |month= ignored (help)
  5. ^ Unknown. "NTSB: Right engine of plane still attached". CNN. Retrieved 2009-01-17.
  6. ^ Samantha Gross. "Passengers in NY plane ordeal marvel they're alive: A female passenger received two broken legs". Associated Press. Retrieved 2009-01-16.
  7. ^ "Pilot hailed for 'Hudson miracle'". BBC. 2009-01-16. Retrieved 2009-01-16.
  8. ^ Robbins, Liz (2009-01-15). "Jet Ditches in Hudson; All Are Said Safe". The New York Times. The New York Times Company. Retrieved 2009-01-15. {{cite news}}: Cite has empty unknown parameter: |coauthors= (help)
  9. ^ Mark V. Rosenker. "NTSB Safety Recommendation" (PDF).
  10. ^ Garuda Indonesia Fl421 at AirDisaster.com retrieved 2 November 2007.
  11. ^ Aviation Safety Network. "McDonnell Douglas DC-9-33CF N935F - St. Croix, Virgin Islands". Retrieved 2006-06-26.
  12. ^ AirSafe.com (2002-03-28). "Jet Airliner Ditching Events". Retrieved 2006-06-26.
  13. ^ http://www.boston.com/news/local/massachusetts/articles/2009/01/16/deadliest_crash_involving_birds_boston_1960/
  14. ^ Kebabjian, Richard. "1956/1956-27.htm". PlaneCrashInfo.com. Retrieved 2006-06-26.
  15. ^ Hokom, Wayne. "Ditch and rescue". Coast Guard stories. Jack's Joint. Retrieved 2006-06-26.
  16. ^ [1]
  17. ^ Aviation Safety Network. "Boeing 747-428 F-GITA Papeete-Faaa Airport (PPT), Tahiti".
  18. ^ Aviation Safety Network. "Boeing 747-409 B-165 - Hong Kong-Kai Tak International Airport (HKG)". Retrieved 2006-06-26.
  19. ^ Smith, Patrick (2002). "Ask the pilot #4: Do seat cushions actually save lives?". Salon.com. Retrieved 2006-06-28.
  20. ^ Nationmaster Encyclopedia
  21. ^ Aircraft Accident Report AAR-78-13 (PDF)
  22. ^ Smith, Patrick (2004). "Ask the pilot #71: Still ignoring those flight-attendant safety lectures?". Salon.com. Retrieved 2006-06-28.

Further reading