Ditching

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An Airbus A320 after ditching in January 2009 ( US Airways flight 1549 )

A ditching is an emergency landing on the water by an aircraft that is not designed for water landings. Ditching is extremely rare in modern aviation.

List of ditching commercial aircraft (selection)

In aircraft Ditchings are a very risky maneuver, because the water surface at typical landing speeds of jet airliners (about 250 km / h) behaves very hard and the structural and hull structure are not designed for placement directly on a surface. Nevertheless, there were ditchings in which all or at least some of the passengers survived:

  • On August 15, 1949, the pilots of a Douglas DC-4 / C-54A of Transocean Air Lines ( aircraft registration number N79998 ) had to ditch a nightly ditch about eight miles off the west coast of Ireland . The plane coming from Rome initially flew far out into the Atlantic instead of landing in Shannon . After the crew noticed their mistake and vice versa, the fuel ran out. Seven passengers and one crew member were killed. Another 50 people were rescued by the crew of a fishing trawler .
  • On June 11, 1952, a Douglas DC-4 splashed down on Pan-Am Flight 526A off the coast of Puerto Rico in heavy seas . All 69 people on board survived the impact. Due to the uncoordinated evacuation and the failure to instruct the passengers on how to use the life jackets, 52 passengers died when the plane went down. This accident led to the international regulation that passengers on longer flights over water must be informed before take-off about where to find the life jackets and how to use them.
  • On June 19, 1954, a Convair CV-240-2 of the Swiss airline Swissair (HB-IRW) had to be ditched in the English Channel due to a lack of fuel . Of the nine people on board (five passengers and four crew members), three passengers drowned because they could not swim and there were no life jackets on board, the rest of them survived. The plane had been on a scheduled flight from Geneva to London . The guilt was blamed on the pilots who failed to get enough fuel before the flight and also failed to realize during the flight that there was insufficient fuel.
  • On 26 March 1955 engine tore a Boeing 377 of Pan American World Airways from in flight. The crew managed to emergency launch the machine about 35 miles off the coast of Oregon . Four of the 23 occupants were killed in the accident.
Ditching Pan-Am flight 6
  • On 16 October 1956 made Boeing 377 on the Pan Am Flight 6 a ditching in the Pacific after two of the four engines had failed. To increase the chances of rescuing the passengers, the plane circled a US Coast Guard ship until dawn before it landed. All 31 people on board survived.
  • On August 21, 1963 was Tu-124 of Aeroflot after the start in Tallinn its landing gear fully retract. The additional drag increased fuel consumption. Due to the thick fog in Tallinn, the pilots decided to move to Leningrad . There the plane circled over the city until the first engine failed. After the second engine failed, the crew ditched the Neva . All 52 inmates survived.
  • On June 21, 1964, the crew of a Douglas DC-3 of the Spanish TASSA ditched after take-off from Palma de Mallorca airport , after both engines failed one after the other while climbing . The machine touched down about 900 meters from the coast, and the captain was injured. There were 25 British vacationers and three crew members on board. It was possible to completely evacuate the aircraft. However, a male passenger climbed back into the cabin to get his bag. He went down with the machine and drowned.
  • On September 16, 1966, a Douglas DC-3 (EC-ACX) operated by Spantax for Iberia suffered an engine failure two minutes after taking off from Tenerife-Los Rodeos Airport . During the necessary ditching, a passenger who had refused to leave the plane drowned. All other 23 passengers and three crew members survived.
  • On November 23, 1996, a Boeing 767-200ER was hijacked on Ethiopian Airlines Flight 961 . After the fuel ran out, the pilots tried to ditch about 500 meters off the coast of the Comoros . The plane broke into several parts. Of the 175 occupants, 50 survived. Some died because they had already inflated their life jackets in the cabin and were thus trapped on board.
  • On January 16, 2002, both engines of a Boeing 737 on Garuda Indonesia flight 421 failed due to heavy hail . Several attempts to restart the engines failed, so that the pilots were forced to land on the Bengawan Solo River near Yogyakarta . Of the 60 people on board, one flight attendant died.
  • On 6 August 2005, made ATR 72 on the tuninter flight 1153 prior to Sicily a ditching, after the fuel had run out. It later turned out that the replaced fuel gauge was intended for a smaller tank. Of the 39 people on board, 20 survived. The wreck was found in three parts.

Approach behavior

Approach procedures for commercial aircraft

With this type of landing, the pilots must ensure that both wings touch down at the same time and that the machine remains in a horizontal flight position. When airliners land, engines that are installed under the wings usually do not withstand the water resistance that suddenly builds up at the moment of immersion due to the landing speed and tear off. The outer skin of the aircraft fuselage should remain intact if possible. Airplanes whose engines are arranged above the wings have an advantage here.

Ditching switch in an Airbus A330

Shortly before touching down, the ditch mode should be activated, if available. It ensures that a large number of flaps are closed (e.g. the outflow valve ) and the machine remains on the water surface longer, so that the chance is increased that passengers can escape the machine via emergency slides before the aircraft sinks into the water . An emergency landing on the mainland is generally considered to be less dangerous than a ditching.

If possible, land against the wind. Landing takes place with the landing gear retracted. You should land with a low sink rate and the lowest possible speed. The landing is carried out as a three-point landing - emphasizing the rear - with parallel water contact of the wings, otherwise there is a risk of rollover.

Ditching of small aircraft

Ditching small aircraft is not quite as dangerous as with commercial aircraft because of the lower landing speed. An emergency landing on the mainland is less dangerous than a ditching.

When the sea is calm, you land against the wind. If the swell is large, you land parallel to the waves, if possible on a crest of the waves. With retractable landing gear , landing is carried out with the landing gear retracted. Landing takes place with a low sink rate and the lowest possible speed. The landing is carried out as a three-point landing, otherwise there is a risk of rollover.

Ditching gliders

Gliders are launched with the landing gear down, the hood locked and the ventilation closed. The belts are to be tightened as tightly as possible.

In the older literature it is sometimes still recommended to go into the water with the landing gear retracted. However, recent tests have shown that modern gliders, due to their aerodynamic shape, dive quite deep below the surface of the water after touchdown, which is very dangerous, especially in shallow water. The resistance of the extended landing gear noticeably reduces the depth of immersion without the risk of the glider overturning.

A waterfall should be parallel to the bank, on the one hand because of the orientation of the waves, on the other hand also to avoid accidentally getting too close to the bank. The surface of the water is approached like a fixed runway and the aircraft touches down with minimal travel. After surfacing, the canopy is opened or, if necessary, thrown off, the harness and parachute are taken off and the cockpit is left. A glider has limited buoyancy.

helicopter

Certain types of helicopters have emergency swimming properties and additional inflatable floats, which are designed to prevent the helicopter from capsizing after a dive. Due to the high center of gravity and the swell , there is a high risk of capsizing , which is why this scenario is part of the content of emergency training for potentially affected groups of people (e.g. flight personnel, offshore workers or members of the navy).

Standstill after ditching

A machine, no matter what type, comes to a standstill solely due to the friction on the water surface acting on the aircraft. With jet aircraft not available reverse thrust available because the engines torn off during splashdown as a rule, except that significant problems were probably the cause of the emergency landing with the engines.

literature

  • Jürgen Mies: Danger manual for pilots (= private pilot library. Volume 1). Motorbuch Verlag, Stuttgart 1994, ISBN 3-613-01577-3 .

Web links

Wiktionary: ditching  - explanations of meanings, word origins, synonyms, translations

Individual evidence

  1. accident report DC-4 N79998 , Aviation Safety Network (English), accessed on March 13 of 2019.
  2. ^ Accident report CV-240 HB-IRW , Aviation Safety Network (English), accessed on March 13, 2019.
  3. Aircraft accident data and report in the Aviation Safety Network (English)
  4. Aircraft accident data and report in the Aviation Safety Network (English)
  5. Peter W. Frey: Dramatic help in the middle of the Atlantic . NZZ of September 27, 2012.
  6. Aircraft accident data and report in the Aviation Safety Network (English)
  7. Plane Crash Info: Douglas Dc-3 EC-AQH, June 21, 1964 , accessed on February 28, 2017.
  8. Juan Carlos Diaz Lorenzo, Ultano Kindelán y TASSA / 2 (in Spanish), accessed February 27, 2017.
  9. ^ Accident report DC-3 EC-ACX , Aviation Safety Network (English), accessed on January 14, 2018.
  10. ^ Aviation Safety Network, July 23, 1969 aviation-safety.net
  11. Aircraft accident data and report in the Aviation Safety Network (English)
  12. Aircraft accident data and report in the Aviation Safety Network (English)
  13. Aircraft accident data and report in the Aviation Safety Network (English)
  14. Aircraft accident data and report in the Aviation Safety Network (English)
  15. Aircraft accident data and report in the Aviation Safety Network (English)
  16. Marc Pitzke: New York celebrates the Hudson miracle. In: Spiegel online. (Accessed January 16, 2009)