Aeroflot Flight 593

Aeroflot Flight 593 was an Aeroflot–Russian International Airlines Airbus A310-304 that crashed into a hillside of the Kuznetsk Alatau mountain range, Kemerovo Oblast, on March 23, 1994. The jet was en route from Sheremetyevo International Airport to Hong Kong Kai Tak International Airport with 75 occupants aboard, of whom 63 were passengers. Most of the passengers were businessmen from Hong Kong and Taiwan who were looking for economic opportunities in Russia. There were no survivors.

No evidence of technical malfunction was found. Cockpit voice and flight data recorders revealed the presence of unauthorised people in the flight deck at the time of the accident; in particular, the pilot's 12-year-old daughter and 16-year-old son were both there. The latter apparently had unknowingly disabled the A310 autopilot's control of the aircraft's ailerons while seated at the controls. The aircraft had then rolled into a steep bank and near-vertical dive from which the pilots were unable to regain control. Unlike Soviet planes with which the crew had been familiar, no audible alarm accompanied the autopilot's partial disconnection and because of this, they remained unaware of what was happening. As a result of the crash investigation, a number of design changes to the A310 autopilot system were recommended.

Aircraft
The aircraft involved in the accident was a leased Airbus A310-304, registration F-OGQS, msn 596, that was delivered new to Aeroflot on December 11, 1992. Powered with two General Electric CF6-80C2A2 engines, the airframe had its maiden flight as F-WWCS on September 11, 1991, and was one of five operating for Russian Airlines, an autonomous division of Aeroflot-Russian International Airlines that was set up for serving routes to the Russian Far East and Southeast Asia. On average, the crew of three operating the aircraft had logged 900 hours on the type.

Description of the accident
The relief pilot, Yaroslav Kudrinsky (Ярослав Кудринский), was taking his two children on their first international flight and they were brought to the cockpit while he was on duty. Aeroflot allowed families of pilots to travel at a discounted rate once per year. With the autopilot active, Kudrinsky, against regulations, offered to let them sit at the controls. First his daughter Yana took the pilot's left front seat. Kudrinsky adjusted the autopilot's heading to give her the impression that she was turning the plane, though she actually had no control of the aircraft. Next, his son Eldar Kudrinsky (Эльдар Кудринский), took the pilot's seat. Unlike his sister, Eldar applied enough force to the control column to contradict the autopilot for 30 seconds.

What nobody in the cockpit knew was that by doing this, he disconnected the aileron's autopilot: the flight computer switched the plane's ailerons to manual control while maintaining control over the other flight systems. The plane did not audibly signal a warning that this had occurred, although an indicator light did come on. It apparently went unnoticed by the pilots, who had previously flown Russian-designed planes which had audible warning signals. The first to notice a problem was Eldar, who observed that the plane was banking right. Shortly after, the flight path indicator changed to show the new flight path of the aircraft as it turned. Since the turn was continuous, the resulting predicted flight path drawn on screen was a 180 degree turn. This indication is similar to the indications shown when in a holding pattern, where a 180 degree turn is intentional to remain in one place. This confused the pilots for nine seconds.

During this confusion, the plane banked past a 45-degree angle (steeper than it was designed for). This increased the g-force on the pilots and crew, making it impossible for them to regain control. After banking as much as 90 degrees, the remaining functions of the autopilot tried to correct the plane's altitude by putting the plane in an almost vertical ascent, nearly stalling the plane. The co-pilot and Eldar managed to get the plane into a nosedive, which reduced the g-force on them and enabled the captain to take the controls. Though he and his co-pilot did regain control, their altitude by then was too low to recover, and the plane crashed at high vertical speed —estimated at 70 m/s (14,000 ft/min)—, killing all aboard. The aircraft crashed gear-up, and all passengers were prepared for an emergency, as they were strapped into their seats. No distress calls were made prior to the crash. Despite the struggles of both pilots to save the aircraft, it was later concluded that if they had simply let go of the control column, the autopilot would have automatically taken action to prevent stalling, thus avoiding the accident.

The wreckage was located on a remote hillside approximately 20 km (12 mi) east of Mezhdurechensk, Kemerovo Oblast, Russia; the flight data recorders were found on the second day of searching. Families of western victims placed flowers on the crash site, while families of Chinese victims scattered pieces of paper with messages written on them around the crash site.

Dramatisation
A season three episode of the Canadian-produced TV series Mayday (Air Emergency, Air Crash Investigation), "Kid in the Cockpit", featured this crash.

Flight number
Although it is common practice for airlines to retire the flight numbers of flights involved in fatal accidents, Nevertheless, the airline has modified its schedules so flight 595 is the only one servicing Hong Kong;, the route is operated on a daily basis using Airbus A330-200 equipment.