Friday, January 13, 2017

January 13, 1982 – Air Florida Flight 90, a Boeing 737 jet, crashes into the 14th Street Bridge shortly after take-off and falls into the Potomac River, killing 78 people -- including four motorists.

Icing on the wings was later blamed for the crash. Modern de-icing procedures at American airports were implemented based on recommendations made after the crash.

On Wednesday, January 13, 1982, Washington National Airport was closed by a heavy snowstorm that produced 6.5" of snow. It reopened at noon under marginal conditions as the snowfall began to slacken.

The scheduled departure time was delayed 1 hour and 45 minutes because of the temporary closing of Washington National Airport. As the plane was readied for departure, a moderate snowfall continued and the air temperature was 24°F.

The Boeing 737 was deiced with a mixture of heated water and monopropylene glycol. The pitots/static ports and engine inlets had to be deiced, but workers did not comply with those rules. The deicing truck was also not working propertly. Instead of 30 percent alcohol, the mix was 18 percent. That was because the nozzle on the truck had been damaged, and replaced by a commercially available nozzle rather than one used specially for deicing trucks. (The operators had no means of knowing that the mixture was wrong, because the trucks lacked a mixture indicator.)

The plane waited in a taxi line for 49 minutes before reaching the takeoff runway. Pilot Larry Wheaton and First Office Roger Pettit had little experience flying in cold or snow. They decided not to return to the gate for deicing, fearing the flight's departure would be even further delayed. Both men were aware that snow and ice were accumulating on the wings when they decided to take off. The flight crew also did not activate the engine anti-ice system, which would have prevented sensors from freezing, ensuring accurate readings.

As they taxied, Wheaton and Pettit decided to get close to a DC-9 that was taxiing just ahead of them. They believed the heat from the DC-9's engines would melt the snow and ice that had accumulated on Flight 90's wings. This blatantly violated the flight manual. That's because doing so actually worsened the icing: The exhaust gases from the other aircraft only partially melted the snow on the wings, but did not disperse it. During takeoff, this slush mixture froze on the wings' leading edges and the engine inlet nose cone.

Takeoff occurred at 3:59 p.m. EST.

With the engine sensors iced over, the engine pressure ratio (EPR) thrust indicators provided false readings.

As the takeoff began, Pettit said several times that the plane did not seem to have as much power as it needed for takeoff, despite the instruments indicating otherwise. Wheaton dismissed these concerns and takeoff proceeded. He may have done so, in part, because control tower operators had told him that another aircraft was 2.5 miles out on final approach to the same runway.

As the plane became airborne, the stick-shaker -- an instrument that warns that the plane is in danger of stalling -- began sounding.

It took the plane just 30 seconds to crash.

Flight 90 was only 350 feet in the air before it began to fall. As it did so, the plane was aiming directly northwest up the Potomac River. As it crashed, its rear undercarriage and tail smashed into the 14th Street Bridge, hitting six cars and a truck. Forty feet of the bridge's wall plunged into the ice-strewn river below.

Eight people on the bridge were hit by the plan. Four died immediately.

The aircraft plunged into the Potomac, with all but the tail section. Both pilots and two of the three flight attendants died instantly. Of the 74 passengers aboard, only 23 survived impact. Nineteen of these were so severely injured, they were unable to escape the sinking airliner and drowned.

Just 5 passengers survived.

Flight attendant Kelly Duncan was the only crew member to survive. Clinging to the tail section, she activated a flotation device and passed Nikki Felch, a severely injured passenger.

Federal offices in Washington had closed early that day due to the blizzard, which caused a massive traffic jam. Traffic made it very difficult for rescue craft and ambulances to reach the crash site. Worse, the Coast Guard tugboat _Capstan_ was downriver on another search-and-rescue mission.

Roger Olian, a sheetmetal worker at St. Elizabeths Hospital, jumped into the water in an attempt to reach the survivors. He only traveled a few yards before coming back, ice sticking to his body. He tried again, this time tied to a rope, but heavy ice prevented him from getting more than 30 feet.

At approximately 4:20 p.m., Park Police helicopter manned by pilot Donald Usher and paramedic Melvin Windsor arrived and began attempting to airlift survivors to shore. First to receive the line was Bert Hamilton, who was treading water about 10 feet from the tail. Fire/rescue personnel and civilians pulled Hamilton ashore. The helicopter then attempted to aid passenger Arland D. Williams, Jr. Williams could not unstrap himself from his seat, and passed the line to flight attendant Kelly Duncan, who was towed to shore. The helicopter now lowered two lifelines, fearing that the survivors had only moments left before succumbing to hypothermia. Williams, still strapped into the wreckage, passed his line to Joe Stiley, who was holding on to severely injured Priscilla Tirado, who was blind due to jet fuel in the eyes. Nikki Felch took the second line. As the helicopter moved toward shore, both Tirado and Felch lost their grip and fell back into the water.

When the helicopter returned, Tirado was too weak to grab the line. Lenny Skutnik, a worker at the Congressional Budget Office, dove into the water and swam out to her, successfully pulling her to shore. Usher now maneuvered the helicopter dangerously close to the iceberg-filled waters, at one point his skids even dipping below the surface. Windsor stepped onto the skid and grabbed Felch by her clothing. The two stood on the skid until the helicopter got them to shore.

By this time, the wreckage had rolled, submerging Arland Williams. He drowned.

The National Transportation Safety Board cited pilot error as the primary cause of the crash.

The crash-damaged span of the 14th Street Bridge was renamed the Arland D. Williams Jr. Memorial Bridge to honor the passenger who died saving others.

Roger Olian and Lenny Skutnik received the Coast Guard's Gold Lifesaving Medal. Williams received the award posthumously. Donald Usher and Melvin Windsor received the Silver Lifesaving Medal.

Usher and Windsor also received the Interior Department's Valor Award.





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