On Friday, the day after a crash landing on the Hudson river that miraculously ended with no fatalities or serious injuries to the 155 people aboard, President Bush spoke to Chesley B. "Sully" Sullenberger, the pilot of Flight 1549. The president praised him for his amazing skills in bringing his plane down safely, for his bravery, and for his heroic efforts to ensure the safety of his passengers and the people in the area.
Sullenberger and his crew followed a well-practiced ditching procedure to land the plane safely on water. Here's a look at the equipment, procedures and thinking that went into the successful landing, now being known as "the miracle on the Hudson."
The A320 is computer controlled, so electric power is required to operate the flight controls.
If the engines were turning they may have provided some electric power.
The alternatives to generate power are an auxiliary power unit on the tail of the aircraft, but the pilots may not have had time to start it.
The other source is the RAT, Ram Air Turbine, which is a propeller-driven device that projects out of the plane, turning into the windstream to generate power.
As they were dealing with the situation, the co-pilot would have read the "ditching checklist," a sequence of procedures to be followed. Pilots and flight attendants are very familiar with the procedures. Procedures are done in a specific orders and include items such as pushing the ditch button, which seals the underbelly of the plane to make it more buoyant
If the pilots had time they would have briefed the flight attendants in the rear of the aircraft.
The pilot would have told the passengers to brace for impact, by bending forward and folding their arms around the back of the seat in front of them, a few minutes before hitting the ground.
The pilot uses a joystick to provide input to the computer systems, which take the input and determine the optimal way to fly the aircraft. For example, in a wind shear situation, the pilot manipulates the joystick and the computer optimizes the position of the plane and holds it. If all the computers on an A320 are working, the plane won't stall.
It's possible that the aircraft could have made it to the Teterboro airport, according to the pilot who spoke with CBSNews.com. He said the pilot probably felt that from the aircraft's descent rate, it was smoother to ditch in the water than on a concrete runway. There could have been a huge drag if the landing gear were down, and he might not have made it, the pilot said.
The landing involves slowing the plane down as much as possible, with the flaps up to slow the aircraft and the landing gear up. The water landing procedures come from the manufacturer of the aircraft.
The aircraft probably had only about a third of its fuel capacity (nearly 8,000 gallons when full), sufficient for the trip from New York to North Carolina. In today's economy, aircraft are not usually loaded with extra fuel, the pilot said. The smaller fuel load helps with the buoyancy, as did the ditch switch and air in the plane.
And despite the extremely cold weather, the elements helped in other ways. The water in the Hudson, which can be quite choppy, was relatively smooth with litle wind or tide influence.