Olympic Airways Flight 3838

On 14 September 1999, Olympic Airways Flight 3838, a flight operating for the Hellenic Air Force, experienced multiple pilot-induced oscillations while over southern Romania, killing seven people. The aircraft—a Dassault Falcon 900B flying from Ellinikon International Airport in Athens, Greece—was flying to Bucharest Henri Coandă International Airport in Bucharest, Romania, for the Interbalkan Conference of Foreign Ministers and was carrying Greek deputy foreign minister Giannos Kranidiotis.

While descending through 15,000 ft, the autopilot disconnected, causing an unfavorable stabilizer trim situation. In response to the disconnection, the pilot flying attempted to correct the pitch of the aircraft by use of the control column. However, this resulted in ten separate pitch oscillations with g-forces that exceeded the maneuvering load factor for the aircraft. As a result, six of the passengers, including Kranidiotis, were killed and one additional passenger died three days after the accident.

The investigation, conducted by the Romanian Civil Aviation Inspectorate, concluded several factors that led to the accident. As the aircraft was climbing out of Athens, the pilots received a warning related to the aircraft's pitch system. The pilots did not properly identify and evaluate the failure and used inappropriate checklists only designed for training. As the aircraft was descending, the pilot flying exerted enough force on the control column to disconnect the autopilot. The continued force on the control column led to the beginning of the pilot-induced oscillations. Additionally, none of the deceased passengers were wearing seatbelts during the descent phase, and this contributed to the severity of the incident.

Accident

On 14 September 1999, SX-ECH was scheduled to depart Ellinikon International Airport in Athens at 18:00 UTC to arrive in Bucharest Henri Coandă International Airport in Bucharest at 19:18 as OAL 3838, using the Olympic Airways ICAO airline code and the Olympic Airways call sign. Pre-flight checklists started at 16:50 and the passengers started boarding at 17:45. The aircraft then took off from runway 33 at Athens at 18:16, and the autopilot was engaged 1 minute and 30 seconds later. During the climb and after the flaps and slats were retracted, the "PITCH FEEL" warning light illuminated on the cockpit warning panel. Captain Androulakis disengaged the autopilot in response, checked the forces on the control column, and reengaged autopilot. However, the warning light remained on for the rest of the climb and cruise. At 19:03, the flight started its descent from 40,000 ft to 15,000 ft with the autopilot engaged in vertical speed mode. During the descent, the indicated airspeed increased from 240 knots to 332 knots. 12 minutes later, First Officer Sinekoglou requested further descent clearance from air traffic control (ATC) to 5,000 ft. However, soon after passing through 15,000 ft, the autopilot disconnected, and Captain Androulakis assumed manual control of the aircraft. During the next 24 seconds, the aircraft experienced 10 pitch oscillations. During these oscillations, the g-forces went from +4.7 g to -3.26 g, which exceeded the design load factor limits on the aircraft of +2.6 g and -1 g. In the cabin, the passengers without their seatbelts fastened were thrown toward the ceiling together with loose items in the cabin. Collisions with objects in the cabin and the ceiling resulted in serious injury and the death of six people, including Kranidiotis. Captain Androulakis was able to recover from the upset 24 seconds after reducing engine power and speed while descending to 13,000 ft. First Officer Sinekoglou declared an emergency to ATC, stating that they had control problems. ATC provided radar vectors for a visual approach to land on runway 08R at Bucharest Airport, where it landed uneventfully at 19:33. The aircraft taxied to the VIP terminal at the airport where emergency services were provided.