Prevention of loss of communication Air China
MAIN CONTENTS summary Analyze of TEM Prevention
summary B767-300 loss of communication near Bordeaux May 4th 2014, Boeing 767-300 performed flight from Rome to Washington. Aircraft was enroute at FL320 over France, when radio communication was lost between ATC and the aircraft. French fighter aircraft were dispatched to intercept the aircraft. The crew restored radio communication shortly after and continued across the Atlantic Ocean to its destination for a safe landing about 8:50 hours later.
summary Loss of communication: may cause air conflict, may affect normal air traffic control and threaten air safety. It is one of critical risks be controlled by Air China.
summary According to the statistics of China civil aviation, the number of communication loss events increased rapidly in recent years. The number of such events in 2013 increased 280% compared to that of 2009 and flights by foreign airlines operated in China accounted for 40%. As the civil aviation industry develops rapidly, the volume of flights increases significantly in China and the airspace becomes much more congested, therefore loss of communication becomes increasingly threatening. 90 80 70 60 50 40 30 20 10 0 2009-2013 Analyse 84 70 69 37 18 2009 2010 2011 2012 2013
Threat and error management threat and error caused by loss of communication are as below: Error Threat Crew error Operational environment ATC error Mechanical failure
Threat and error management Typical event No.1 Oct. 2011 A321 PEK-HKG 50 minutes after departure, ATC could not contact with the crew and lost communication about 1 hour and 15 minutes. Air contingency plan was launched by CAAC Southern and Central Bureau and more than 10 aircrafts changed their flight levels/routes for avoidance.
Threat and error management Error 1 : In flight, the crew did not monitor primary frequency, nor switched timely to the frequency given by ATC. Error 2: The crew failed to monitor emergency frequency or the emergency frequency was not set. Error 3:The crew failed to carry out radio check for long radio quiet situation.
Threat and error management Typical event No.2 Jun. 2013 A320 CTU-CZX After departure, the crew changed VHF1 and VHF2 while switching frequency and this caused communication loss for 9 minutes.
Threat and error management Error:The primary frequency was overridden VHF2
Typical human error Speaker volume was set too low or turned off and the pilot responsible for communication did not wear the headphone as required. The primary frequency was overridden crew ATC The crew copied incorrectly the frequency given by ATC, and did not perform cross check. In flight, the crew did not monitor primary frequency, nor switched timely to the frequency given by ATC. The crew failed to monitor emergency frequency or the emergency frequency was not set. The crew failed to carry out radio check for long radio quiet situation The ATC controller failed to correct the pilot s incorrect read-back in time. English pronunciation is not clear.
Threat and error management Environmental threat Operational environment Mechanical failure Typical threat Communication Congestion. Radio communications interrupted. Key equipment failure of communication system PTT(push to talk)stucked in the transmit position.
Prevention of loss of communication Considering the potential hazard of communication loss, Civil Aviation Administration of China revised the terms of incidents to carry out strict evaluation criteria: - Two-way radio communication loss resulting in other aircraft avoidance or two-way radio communication loss lasting 10 minutes or more under area control. - Two-way radio communication loss lasting for 3 minutes or more in terminal control area.
Prevention of loss of communication Air China considers in flight communication loss as an important risk and has carried out the risk prevention work by improving procedures/checklist, carrying out safety education and simulator training.
Prevention of loss of communication Preventive DEFENSES RECOVERY DEFENSES tune to wrong frequency Not monitor emergency frequency equipment failure No signal of communicatio n equipment Revise the operational program and QRH simulator training Safety training ATC COM M. LOSS HF/VHF/SA TCOM/DAT ALINK Crew loss of communicati on procedure AOC loss of communicatio n procedure Mid-Air Collision
Prevention of loss of communication 1. Revising operation procedures and QRH: Regulation on use of headphone: pilot responsible for communication must wear headphones all through the flight phase, and flight crew must wear headphones all through the flight phase except for cruising phase. Record of instruction: ATC instructions must be recorded in the communication log, and the crew must cross-check when tuning the frequency. Use of equipment: setting the frequency by overriding is prohibited. Handling of radio quiet situations: If the primary frequency is not used for voice communication for a long time, crew members need to make radio check with ATC. Add the inspection item about confirming VHF2 at 121.5MHZ in before engine start checklist.
Prevention of loss of communication 2. Safety training and supervision Carry out safety training regularly. For example, typical case study, risk reminder published on flight preparation website and aviation safety information system. Establish the checklist for standard procedure performance, carry out check for inspection for radio communication procedure performance especially during line operation check and simulator training inspection.
Prevention of loss of communication 3. Amend the relevant requirements for simulator training. In simulator training, instructors and trainees should imitate real use of radio communication equipment and frequency setting and use headphone and speaker for instructing and training.
Prevention of loss of communication 4. Improve emergency procedure for communication loss Establish radio communication loss procedure, and carry out training for the crew. Establish AOC procedures for communication system failure. In case of radio communication failure between crew and ATC, AOC will contact area control and report the aircraft s flight data such as altitude and route, and transfer the control instructions to the flight crew. In addition, HF, VHF and ACARS are installed on most of Air China aircrafts. And the voice communication and datalink function of SATCOM on widebodied aircraft are available during flight. SATCOM installation on B737NG and A320 is ongoing.
Prevention of loss of communication Above mentioned procedures successfully decrease the loss of communication. In 2012, the rate of losing communication event is 0.5 per 10000 flights, and the rate of 2013 reduced to 0.1.
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