Olympic Airways Flight 411

Olympic Airways Flight 411 was an international flight from Ellinikon International Airport bound for John F. Kennedy International Airport and operated by Olympic Airways using a Boeing 747-200. On August 9, 1978, the flight came close to crashing in downtown Athens. Despite maneuvers near the edge of the flight envelope, none of the 418 passengers and crew suffered serious injury.

Based on the flight data recorder and information supplied by Olympic Airways, Boeing found that engine No. 3 shut down at rotation and that approximately nine seconds later the crew switched off the water injection pumps. An Olympic Airways investigation found that the flight engineer had misinterpreted the extinguished No. 3 "WATER FLOW" warning light as indicating that the water supply had run out. Go-around thrust was not initially applied to the remaining engines; thrust was increased after a delay of approximately 30 seconds, although it initially remained below go-around thrust on most engines. Boeing concluded that no additional malfunction of the airframe or engines caused the poor climb performance; rather, shutting off the water injection reduced available thrust on an aircraft that was already takeoff-climb limited. The aircraft recovered after the crew lowered the nose to accelerate and increased engine thrust.

Captain Sifis Migadis and Captain Kostas Fikardos managed to keep the aircraft in the air at an extremely low altitude below minimal speed. All Boeing simulations of the flight resulted in crashes.

Background

The Boeing 747 was the first wide-body aircraft. It was a prestige aircraft in the 1970s and purchased by many airlines as a fleet flagship. Olympic Airways received its first 747 in 1973. Olympic Airways was the flag carrier for Greece and had purchased 747s for some of its prime routes, including a nonstop between Athens and New York. This meant that large numbers of American tourists could be accommodated in one flight at lower per-seat costs to the airlines.

Athens lies in the center of four large mountains: Mount Aigaleo to the west, Mount Parnitha to the north, Mount Pentelicus to the northeast and Mount Hymettus to the east. The geographical area is called Athens Basin or the Attica Basin (Λεκανοπέδιο Αθηνών/Αττικής). The meteorology of Athens is deemed to be one of the most complex in the world because its mountains cause a temperature inversion phenomenon. The temperature that day was 32 C.

In command was 55-year-old Sifis Migadis, who had 32 years of experience with Olympic. The co-pilot, Konstantinos "Kostas" Fikardos, was equally experienced and was a close friend of Migadis.

Flight summary

According to Boeing, engines 3 and 4 idled lower than usual as the aircraft taxied. The plane initially took off and climbed normally. Boeing states that around nine seconds after engine #3 failure, the water pump switch was turned off, when the flight crew misinterpreted the "water flow" warning as "water run-out". Speed decreased and altitude was lost.

The two captains, contrary to the aircraft flight manual, immediately ordered the landing gear retracted when the plane was 35 ft above the runway. Migadis and Fikardos used their knowledge of aerodynamics to prevent the plane from stalling. The minimum speed for a 747 is 180 mph. The pilots needed to fly level and avoid turning as much as possible. They also focused on getting the plane away from the city and to an unpopulated area, like Mount Aigaleo, to reduce the loss of lives if the plane crashed. While Migadis and Fikardos flew the plane, the engineer focused on the problems with the engines.

The plane climbed sluggishly to an altitude of just 209 ft as it approached the 200 ft Pani Hill in Alimos, after which the plane lost altitude. As it passed over Kallithea, Nea Smyrni, and Andrea Syngrou Avenue, its altitude was only 180 ft and its speed was 160 mph. The plane flew just above apartment rooftops and took down some television antennas. At some point, Fikardos and Migadis lowered the nose of the plane to gain speed and the engineer was able to increase the engines' power. When the speed reached 170 mph, Migadis and Fikardos worked on increasing altitude and heading towards the sea.

The larger obstacle of Mount Aigaleo at 1539 ft was of great concern because the low airspeed and minimal altitude did not leave the flight crew enough room to execute a normal banked turn. At 2:05 pm, a light headwind gave the plane some altitude, which allowed Migadis and Fikardos to make a gradual turn to avoid crashing into the mountain. After flying over the sea to dump fuel, the aircraft returned to Ellinikon International Airport safely.