An in-flight breakup would have scattered wreckage over a wide area, Tilmon said. If the jet hit the water at a steep angle, at high speed, it would likely have taken much of its frame and contents down into the deep with it.
The most successful water landing in recent history was the so-called "Miracle on the Hudson" in 2009, when the crew of a crippled US Airways flight landed safely on the river off Manhattan after losing both engines. The Airbus A320 remained intact, and all 155 passengers and crew made it safely off the aircraft.
But the Hudson is "pretty relaxed by comparison" to the remote Indian Ocean, "where you have swells of 10, 12, 16 feet," Tilmon said. "It's pretty difficult to make that kind of landing on water."
http://www.cnn.com/2014/04/10/world/...html?hpt=hp_t1