The crash of MD-82 near Urumqi

MD-82 with registration number B-2141 (serial number 49849, serial number 1772) was released in June 1991 at the Shanghai aircraft factory under license from McDonnell Douglas . The plane was handed over to the General Directorate of Civil Aviation of the People's Republic of China , which on December 31, 1991 sent it to China Northern Airlines . On the liner, two Pratt & Whitney JT8D-217A turbofan engines were installed (traction - 20 thousand pounds each) ^[1] .

The aircraft performed domestic passenger flight CJ6901 from Shenyang to Urumqi with an intermediate landing in Beijing , and there were 92 passengers and 10 crew members on board when departing to Urumqi. The crew performed a normal approach when the dispatcher indicated that the standard altimeter setting was 1024 kPa. However, due to a violation of the phraseology of radio exchange, the crew mistakenly decided that this setting was not given at sea ​​level , but at the level of the airfield , after which the commander put it on his altimeter . In fact, the airdrome level pressure was 947 kPa, and an incorrect pressure setting of 1024 led to the fact that the left altimeter began to overestimate altitude readings by 2128 feet (649 meters). Focusing now on the incorrect readings of the altimeter, the crew turned off the autopilot and began to perform a manual reduction. Performing a descent in fog, the pilots did not notice how they descended under the glide path , because of which its indicator shifted to the horizon . Trying to determine their position according to the course-glide path system , the crew did not pay attention to two signals from the system of dangerous proximity to the ground and four voice warnings "PULL UP" ( Climb ). When the pilots realized that they were at dangerously low altitude, they immediately turned on the autopilot, but forgot about the automatic traction control . The autopilot turned the car into a climb, but since the engines did not reach the required mode, this led to the fact that the plane was just starting to lose altitude. Then the low-flying Douglas crashed into power lines and, having lost speed, crashed into a field 2.2 kilometers from the end of the strip. The accident killed 12 people: 4 crew members and 8 passengers ^{[2] [3]} .

The disaster occurred due to several factors:

1. The aircraft commander incorrectly set the pressure on his altimeter, as a result of which he began to give over-readings.
2. The non-standard terminology used by the dispatcher during radio conversations, because of which the crew incorrectly perceived the information received.
3. The pilots did not respond in time to the warnings of the system, which warned of a dangerous approach to the ground, and then took the wrong actions to correct the situation.

• Description of the incident on the Aviation Safety Network