공 중 충 돌 예 방 Mid-Air Collision Avoidance 한국민간항공조종사협회 국제협력이사 정 인재 (대한항공 B-737 부조종사) 2002-10-29 교통안전공단 항공안전세미나

TCAS 회피기동 사례연구 Bulletin E u r o c o n t r o l TCAS 회피기동 사례연구 Bulletin SAFETY FLASH http://www.eurocontrol.int/acas 유럽 31개 국의 항공교통관제시스템 개발기구 스위스 공중충돌사고 전부터 준비된 내용은 안타깝게도 한달 늦은 8월에 발표되었으나, 우리에게 중요한 TCAS 관련 정보를 제공한다. FOLLOW the RA ! 2002-10-29 교통안전공단 항공안전세미나

Eurocontrol 연구의 결론 TCAS II 장비가 상당한 안전 혜택을 제공하고 있음을 확인할 수 있으나. . . RA에 대한 부실한 반응에 의해 심각한 저해를 받을 수 있는 것으로 나타났다. RA 회피지시에 상반되는 기동 사례는 이러한 안전 혜택을 무효화 했다. 2002-10-29 교통안전공단 항공안전세미나

사례 1: RA와 상반되는 ATC 회피지시 2002-10-29 교통안전공단 항공안전세미나 Two aircraft level at FL70 are being radar vectored by the approach controller: An ATR72 is heading 185 - A B737 is on opposite track heading 345 - A third aircraft (SW3) level at FL50 is heading east. All aircraft are in IMC. Because the controller is occupied with the resolution of another conflict, the B737 is instructed, late, to descend to FL60 when the aircraft are slightly less than 5 NM head on. Both aircraft are at the same level and converging quickly. The TCAS II of each aircraft triggers a coordinated RA a few seconds later: The ATR72 pilot receives a “Descend” RA that he follows. The B737 pilot receives a “Climb” RA that he does not follow. He continues to comply with the ATC instruction. The ATR72 pilot immediately informs the controller that he has a “Descend” RA using the standard phraseology. However just after, the controller repeats to the B737 the instruction to descend to FL60 for avoiding action. The B737 pilot, who has reported afterwards that he “had to avoid TCAS alert” descends through FL60. This opposite reaction to his “Climb” RA induces an “Increase Descent” RA on-board the ATR72, which leads the pilot to deviate much more than initially required by TCAS II. This large vertical deviation induces a new TCAS conflict with the SW3 level at FL50. If the B737 pilot had responded correctly to his “Climb” RA, the vertical separation between the ATR72 and the B737 would have been 600 ft (i.e. 300 ft vertical deviation for each). 2002-10-29 교통안전공단 항공안전세미나

사례 1: RA와 상반되는 ATC 회피지시 2002-10-29 교통안전공단 항공안전세미나 Two aircraft level at FL70 are being radar vectored by the approach controller: An ATR72 is heading 185 - A B737 is on opposite track heading 345 - A third aircraft (SW3) level at FL50 is heading east. All aircraft are in IMC. Because the controller is occupied with the resolution of another conflict, the B737 is instructed, late, to descend to FL60 when the aircraft are slightly less than 5 NM head on. Both aircraft are at the same level and converging quickly. The TCAS II of each aircraft triggers a coordinated RA a few seconds later: The ATR72 pilot receives a “Descend” RA that he follows. The B737 pilot receives a “Climb” RA that he does not follow. He continues to comply with the ATC instruction. The ATR72 pilot immediately informs the controller that he has a “Descend” RA using the standard phraseology. However just after, the controller repeats to the B737 the instruction to descend to FL60 for avoiding action. The B737 pilot, who has reported afterwards that he “had to avoid TCAS alert” descends through FL60. This opposite reaction to his “Climb” RA induces an “Increase Descent” RA on-board the ATR72, which leads the pilot to deviate much more than initially required by TCAS II. This large vertical deviation induces a new TCAS conflict with the SW3 level at FL50. If the B737 pilot had responded correctly to his “Climb” RA, the vertical separation between the ATR72 and the B737 would have been 600 ft (i.e. 300 ft vertical deviation for each). 2002-10-29 교통안전공단 항공안전세미나

사례 2: RA와 상반되는 ATC 회피지시 A321 B737 FL270 FL280 2002-10-29 Two aircraft level at FL70 are being radar vectored by the approach controller: An ATR72 is heading 185 - A B737 is on opposite track heading 345 - A third aircraft (SW3) level at FL50 is heading east. All aircraft are in IMC. Because the controller is occupied with the resolution of another conflict, the B737 is instructed, late, to descend to FL60 when the aircraft are slightly less than 5 NM head on. Both aircraft are at the same level and converging quickly. The TCAS II of each aircraft triggers a coordinated RA a few seconds later: The ATR72 pilot receives a “Descend” RA that he follows. The B737 pilot receives a “Climb” RA that he does not follow. He continues to comply with the ATC instruction. The ATR72 pilot immediately informs the controller that he has a “Descend” RA using the standard phraseology. However just after, the controller repeats to the B737 the instruction to descend to FL60 for avoiding action. The B737 pilot, who has reported afterwards that he “had to avoid TCAS alert” descends through FL60. This opposite reaction to his “Climb” RA induces an “Increase Descent” RA on-board the ATR72, which leads the pilot to deviate much more than initially required by TCAS II. This large vertical deviation induces a new TCAS conflict with the SW3 level at FL50. If the B737 pilot had responded correctly to his “Climb” RA, the vertical separation between the ATR72 and the B737 would have been 600 ft (i.e. 300 ft vertical deviation for each). B737 FL280 2002-10-29 교통안전공단 항공안전세미나

ATC: “Descend Immediately FL270” 사례 2: RA와 상반되는 ATC 회피지시 A321 B737 FL290 RA: “Descend” X ATC: “Descend Immediately FL270” FL280 ATC: “Climb FL290” RA: “Climb” FL270 Two aircraft level at FL70 are being radar vectored by the approach controller: An ATR72 is heading 185 - A B737 is on opposite track heading 345 - A third aircraft (SW3) level at FL50 is heading east. All aircraft are in IMC. Because the controller is occupied with the resolution of another conflict, the B737 is instructed, late, to descend to FL60 when the aircraft are slightly less than 5 NM head on. Both aircraft are at the same level and converging quickly. The TCAS II of each aircraft triggers a coordinated RA a few seconds later: The ATR72 pilot receives a “Descend” RA that he follows. The B737 pilot receives a “Climb” RA that he does not follow. He continues to comply with the ATC instruction. The ATR72 pilot immediately informs the controller that he has a “Descend” RA using the standard phraseology. However just after, the controller repeats to the B737 the instruction to descend to FL60 for avoiding action. The B737 pilot, who has reported afterwards that he “had to avoid TCAS alert” descends through FL60. This opposite reaction to his “Climb” RA induces an “Increase Descent” RA on-board the ATR72, which leads the pilot to deviate much more than initially required by TCAS II. This large vertical deviation induces a new TCAS conflict with the SW3 level at FL50. If the B737 pilot had responded correctly to his “Climb” RA, the vertical separation between the ATR72 and the B737 would have been 600 ft (i.e. 300 ft vertical deviation for each). 결과: < 2NM 수평 분리 100 FT 수직 분리 2002-10-29 교통안전공단 항공안전세미나

사례 3: 잘못된 항적정보 + 착시현상 2002-10-29 교통안전공단 항공안전세미나 Two aircraft level at FL70 are being radar vectored by the approach controller: An ATR72 is heading 185 - A B737 is on opposite track heading 345 - A third aircraft (SW3) level at FL50 is heading east. All aircraft are in IMC. Because the controller is occupied with the resolution of another conflict, the B737 is instructed, late, to descend to FL60 when the aircraft are slightly less than 5 NM head on. Both aircraft are at the same level and converging quickly. The TCAS II of each aircraft triggers a coordinated RA a few seconds later: The ATR72 pilot receives a “Descend” RA that he follows. The B737 pilot receives a “Climb” RA that he does not follow. He continues to comply with the ATC instruction. The ATR72 pilot immediately informs the controller that he has a “Descend” RA using the standard phraseology. However just after, the controller repeats to the B737 the instruction to descend to FL60 for avoiding action. The B737 pilot, who has reported afterwards that he “had to avoid TCAS alert” descends through FL60. This opposite reaction to his “Climb” RA induces an “Increase Descent” RA on-board the ATR72, which leads the pilot to deviate much more than initially required by TCAS II. This large vertical deviation induces a new TCAS conflict with the SW3 level at FL50. If the B737 pilot had responded correctly to his “Climb” RA, the vertical separation between the ATR72 and the B737 would have been 600 ft (i.e. 300 ft vertical deviation for each). 2002-10-29 교통안전공단 항공안전세미나

사례 3: 잘못된 항적정보 + 착시현상 2002-10-29 교통안전공단 항공안전세미나 Two aircraft level at FL70 are being radar vectored by the approach controller: An ATR72 is heading 185 - A B737 is on opposite track heading 345 - A third aircraft (SW3) level at FL50 is heading east. All aircraft are in IMC. Because the controller is occupied with the resolution of another conflict, the B737 is instructed, late, to descend to FL60 when the aircraft are slightly less than 5 NM head on. Both aircraft are at the same level and converging quickly. The TCAS II of each aircraft triggers a coordinated RA a few seconds later: The ATR72 pilot receives a “Descend” RA that he follows. The B737 pilot receives a “Climb” RA that he does not follow. He continues to comply with the ATC instruction. The ATR72 pilot immediately informs the controller that he has a “Descend” RA using the standard phraseology. However just after, the controller repeats to the B737 the instruction to descend to FL60 for avoiding action. The B737 pilot, who has reported afterwards that he “had to avoid TCAS alert” descends through FL60. This opposite reaction to his “Climb” RA induces an “Increase Descent” RA on-board the ATR72, which leads the pilot to deviate much more than initially required by TCAS II. This large vertical deviation induces a new TCAS conflict with the SW3 level at FL50. If the B737 pilot had responded correctly to his “Climb” RA, the vertical separation between the ATR72 and the B737 would have been 600 ft (i.e. 300 ft vertical deviation for each). 2002-10-29 교통안전공단 항공안전세미나

X 사례 4: 비효율적인 Visual 회피기동 B747 DC10 FL370 FL370 2002-10-29 Two aircraft level at FL70 are being radar vectored by the approach controller: An ATR72 is heading 185 - A B737 is on opposite track heading 345 - A third aircraft (SW3) level at FL50 is heading east. All aircraft are in IMC. Because the controller is occupied with the resolution of another conflict, the B737 is instructed, late, to descend to FL60 when the aircraft are slightly less than 5 NM head on. Both aircraft are at the same level and converging quickly. The TCAS II of each aircraft triggers a coordinated RA a few seconds later: The ATR72 pilot receives a “Descend” RA that he follows. The B737 pilot receives a “Climb” RA that he does not follow. He continues to comply with the ATC instruction. The ATR72 pilot immediately informs the controller that he has a “Descend” RA using the standard phraseology. However just after, the controller repeats to the B737 the instruction to descend to FL60 for avoiding action. The B737 pilot, who has reported afterwards that he “had to avoid TCAS alert” descends through FL60. This opposite reaction to his “Climb” RA induces an “Increase Descent” RA on-board the ATR72, which leads the pilot to deviate much more than initially required by TCAS II. This large vertical deviation induces a new TCAS conflict with the SW3 level at FL50. If the B737 pilot had responded correctly to his “Climb” RA, the vertical separation between the ATR72 and the B737 would have been 600 ft (i.e. 300 ft vertical deviation for each). 2002-10-29 교통안전공단 항공안전세미나

사례 4: 비효율적인 Visual 회피기동 X B747 DC10 FL370 RA: “Descend” B747 DC10 FL370 X ATC: “Descend” 잘못된 Call Sign RA: “Climb” Two aircraft level at FL70 are being radar vectored by the approach controller: An ATR72 is heading 185 - A B737 is on opposite track heading 345 - A third aircraft (SW3) level at FL50 is heading east. All aircraft are in IMC. Because the controller is occupied with the resolution of another conflict, the B737 is instructed, late, to descend to FL60 when the aircraft are slightly less than 5 NM head on. Both aircraft are at the same level and converging quickly. The TCAS II of each aircraft triggers a coordinated RA a few seconds later: The ATR72 pilot receives a “Descend” RA that he follows. The B737 pilot receives a “Climb” RA that he does not follow. He continues to comply with the ATC instruction. The ATR72 pilot immediately informs the controller that he has a “Descend” RA using the standard phraseology. However just after, the controller repeats to the B737 the instruction to descend to FL60 for avoiding action. The B737 pilot, who has reported afterwards that he “had to avoid TCAS alert” descends through FL60. This opposite reaction to his “Climb” RA induces an “Increase Descent” RA on-board the ATR72, which leads the pilot to deviate much more than initially required by TCAS II. This large vertical deviation induces a new TCAS conflict with the SW3 level at FL50. If the B737 pilot had responded correctly to his “Climb” RA, the vertical separation between the ATR72 and the B737 would have been 600 ft (i.e. 300 ft vertical deviation for each). 최종 순간 난폭한 회피조작에 의해 승객/승무원 부상자 다수 발생 B747은 DC10 바로 밑을 (보고된) 10 METER 거리로 스쳐 지났음 2002-10-29 교통안전공단 항공안전세미나

사례 5 / 6: 최고 고도에서의 “Climb” RA 2002-10-29 교통안전공단 항공안전세미나

사례 7: 양 조종사의 올바른 반응 2002-10-29 교통안전공단 항공안전세미나 An A340 and an A319, which are departing from two different airports, are in contact with different controllers but in the same airspace. The A340, in contact with the departure controller, is cleared to climb to FL150 with an initial heading 090. The A340 climbs slowly and is planned to climb above the A319. The A319, which is level at FL90 and also heading east, is already in contact with the en-route centre. When passing through FL100, the A340 is turned to the right by the departure controller. At the same time, the A319 is cleared by mistake by the en-route controller to climb to FL210, which induces a conflict with the A340. The en-route controller detects the conflict and instructs the A319 to stop climb at FL100. The A319 pilot replies that he has already passed FL100 and that he is descending back to FL100. However, because of the simultaneous horizontal and vertical convergence, the TCAS II of each aircraft triggers a coordinated RA: -  the A340 receives a “Descend” RA that he follows correctly despite the clearance to climb to FL150 -  the A319 receives a “Climb” RA that he also follows correctly even though he has already started his manoeuvre to descend back to FL100 In this event, the correct responses to the RAs by both pilots provide more than the TCAS II vertical separation objective. 2002-10-29 교통안전공단 항공안전세미나

사례 7: 양 조종사의 올바른 반응 2002-10-29 교통안전공단 항공안전세미나 An A340 and an A319, which are departing from two different airports, are in contact with different controllers but in the same airspace. The A340, in contact with the departure controller, is cleared to climb to FL150 with an initial heading 090. The A340 climbs slowly and is planned to climb above the A319. The A319, which is level at FL90 and also heading east, is already in contact with the en-route centre. When passing through FL100, the A340 is turned to the right by the departure controller. At the same time, the A319 is cleared by mistake by the en-route controller to climb to FL210, which induces a conflict with the A340. The en-route controller detects the conflict and instructs the A319 to stop climb at FL100. The A319 pilot replies that he has already passed FL100 and that he is descending back to FL100. However, because of the simultaneous horizontal and vertical convergence, the TCAS II of each aircraft triggers a coordinated RA: -  the A340 receives a “Descend” RA that he follows correctly despite the clearance to climb to FL150 -  the A319 receives a “Climb” RA that he also follows correctly even though he has already started his manoeuvre to descend back to FL100 In this event, the correct responses to the RAs by both pilots provide more than the TCAS II vertical separation objective. 2002-10-29 교통안전공단 항공안전세미나

Eurocontrol 연구의 결론 FOLLOW the RA ! TCAS는 최후의 보루 안전장비 짧은 시간 내에 즉각적인 반응 필요 (5 ~ 2.5초) 관제사의 인가지시와 상반되는 회피기동 경우에도 조종사는 반드시 RA 지시를 따른다. 관제사의 RADAR 항적정보는 TCAS에 비해 정확도가 낮음. Max Perf Ceiling에서의 “Climb” RA 지시를 위반하지 않는다. Visual Acquisition에 의존할 수 없으며, RA에 우선하지 않는다. (또 다른 항적의 가능성을 주의해야 한다.) 조종사는 반드시 ATC에 통보한다 (A. S. A. P.) 2002-10-29 교통안전공단 항공안전세미나

TCAS 시스템 주의사항 관제사는 TCAS 경보를 받지 않으며, 조종사의 레디오 통보에 의존한다. 2002-10-29 교통안전공단 항공안전세미나

분리기준 초과시 관제사의 역할 짧은 시간 내에 . . . 조우상황 평가 (Assess) 항적 충돌가능 상황 인지 (Detect) 조우상황 평가 (Assess) 해결책 강구 (Develop Solution) 간단명료한 지시 (Communicate) 조종사에게 즉시 전달 2002-10-29 교통안전공단 항공안전세미나

TCAS II 對 ATC 레이더 정보 비교 ATC 레이더 TCAS II TCAS 정보: 최소 4X 정확한 최대 4X 최신 정보 고도 단위: 100 FT 고도 Update 율: 매 4 ~ 10 초 Update Lag: 최고 500 ft 오차 급기동시 Trend 정보 신뢰성 문제 TCAS II 고도 단위: 25 FT 고도 Update 율: 매 1 초 단위 TCAS 정보: 최소 4X 정확한 최대 4X 최신 정보 2002-10-29 교통안전공단 항공안전세미나

SEE & AVOID 개념의 한계 착시 유발 가능 고 고도 저 고도 상대 항공기 의도 정보 부재 기타 항적 존재 가능 IFR 항적 거리 / 방향 / 고도차이 인지 난이 저 고도 저속도 자세 (HI AOA) 상승 / 강하 여부 인지 난이 상대 항공기 의도 정보 부재 기타 항적 존재 가능 2002-10-29 교통안전공단 항공안전세미나

TCAS II RVSM 경보기준 최신 Version 7.0 : 1000 FT 고도분리 TA: 850 FT RA: 700 FT 기존 V 6.04a TA: 1200 FT RA: 800 FT 2002-10-29 교통안전공단 항공안전세미나

TCAS II 장비의 설계특성 Multiple 항적 복합적 상황처리 가능 상승/강하에 역행하는 회피지시 지양 두 항공기 모두 기동 중일 경우 RA 경보 가능성 증가 고도변경시 인가된 고도에 접근하면 (<1000FT) 1000 FPM 이하로 줄여, RA 방지 / TA 최소화 2002-10-29 교통안전공단 항공안전세미나

관제사 준수사항 TA는 관제사에게 통보 금지 (표준용어 없음) RA 회피기동이 통보될 경우 관제사는: 항공기 고도 / 항로 변경을 지시해서는 않되며, PANS-RAC Doc. 4444에 명시된 정보만을 제공한다. 관제사는 RA 회피기동 지시에 의해 인가된 항로/고도를 이탈하는 항공기에 관하여 분리기준을 적용할 책임이 없다. “The controller is not responsible for the provision of separation for an aircraft which is deviating from a clearance in response to an RA.” 2002-10-29 교통안전공단 항공안전세미나

조종사 준수사항 TA 발부시: RA 발부시: Lateral Offset은 인가되지 않은 절차이다. 가급적 관제사에게 항적위치를 묻지 않는다 (Should Not) TA 만으로의 회피기동 금지 (Shall Not) RA 발부시: RA를 최대한 정확하게 따른다 (Should) RA 지시에 상반되는 기동 금지 (Shall Not) RA 를 충족하기 위한 최소한의 기동에 한한다 (Shall) “Clear of Conflict” 발부 > 즉시 인가고도 복귀 (Shall) Lateral Offset은 인가되지 않은 절차이다. 2002-10-29 교통안전공단 항공안전세미나

표준항공교통관제절차 (1) 2-1-27 공중충돌회피장치 (TCAS) 회피조언 (TCAS Resolution Advisories) 가. 관할 관제구역에 있는 항공기가 TCAS에 의한 회피 조언(RA)에 따라 비행하고 있다고 통보할 때는, 조종사가 수행 중이라고 통보해준 RA에 상반되는 관제지시를 발부해서는 안 된다. 2002-10-29 교통안전공단 항공안전세미나

표준항공교통관제절차 (2) 나. TCAS RA에 대한 회피기동을 하고 있는 항공기 근처의 다른 항공기가 회피기동을 알고 있다고 보고하지 않는 한, 적절히 관제지시, 안전경보 및 교통조언을 계속 발부해야 한다. 예: “AAR257, Be advised 12 o’clock traffic is under TCAS climb (or descent), (적절한 지시)” 2002-10-29 교통안전공단 항공안전세미나

표준항공교통관제절차 (3) 다. 일단 회피기동 하고있는 항공기가 RA에 따라 기동을 시작했다면, 관제사는 RA에 반응하는 항공기와 다른 항공기. . . 간의 표준분리 제공에 대한 책임이 없다. 2002-10-29 교통안전공단 항공안전세미나

표준항공교통관제절차 (4) 라. TCAS RA 경보에 따라 기동을 시작할 때 조종사는 가능한 빨리 ATC에 다음과 같이 통보해야 한다. 예: “Taegu Control, KAL321 TCAS Climb (/Descent).” 2002-10-29 교통안전공단 항공안전세미나

표준항공교통관제절차 (5) 마. TCAS 충돌위험이 해소되었을 경우, 조종사는 ATC에 사전에 배정된 Clearance나 그 이후에 발부한 지시대로 복귀하고 있음을 통보해야 한다. 예: “Taegu Control, AAR321, Clear of conflict, returning to assigned clearance.” 또는 “TCAS Climb Completed, 10,000 Resumed.” 2002-10-29 교통안전공단 항공안전세미나

표준항공교통관제절차 (6) 바. 관제사가 발부한 허가를 조종사가 RA로 인하여 수행할 수 없을 경우에는 다음과 같이 보고해야 한다. 조종사 : Unable to Comply, TCAS RA. 관제사 : Roger. (또는 대체 허가) 2002-10-29 교통안전공단 항공안전세미나

COMPANY PROCEDURE AUTOPILOT = 동 AIR DATA COMPUTER 인가고도 복귀 COORDINATION - 121.5 ? 의무보고기준 - 1000FT 이상 고도변경시 RVSM RA 발행 변경 - 800FT >> 700FT RA - ATC 통보 의무 준수 조항 부재 2002-10-29 교통안전공단 항공안전세미나

ATC 통보 표준예문 RA 회피기동 시 가능하면 RA와 상반되는 관제지시는 반드시 “Inchon Control, 8321, TCAS Climb(/Descent).” RA와 상반되는 관제지시는 반드시 “Inchon Control, 789, Unable Climb(/Descent).” 또 는 “Inchon Control, 123, Unable to Comply, TCAS RA (Resolution Advisory).” 2002-10-29 교통안전공단 항공안전세미나

질 문 사 항 ? http://www.pilots.or.kr alpa-k@hanmail.net TEL: 662-2297, 8 질 문 사 항 ? http://www.pilots.or.kr alpa-k@hanmail.net TEL: 662-2297, 8 FAX: 662-2294 2002-10-29 교통안전공단 항공안전세미나