Windshear Escape Maneuver

한 줄 요약: Windshear 감지 → “WINDSHEAR TOGA” call → TO/GA, Max thrust, Wings level, Pitch 15°, Gear/Flap 변경 금지

Trigger (POM 8.3)

WINDSHEAR warning/caution — 이륙 또는 접근 중 windshear 감지 시 (POM 8.3)

Windshear 경고 유형:

• Predictive (PWS): “MONITOR RADAR DISPLAY” (caution) / “WINDSHEAR AHEAD, WINDSHEAR AHEAD” (warning, takeoff) / “GO-AROUND, WINDSHEAR AHEAD” (warning, approach) (POM 8.3)
• Reactive (GPWS): Two-tone siren + “WINDSHEAR, WINDSHEAR, WINDSHEAR” — 1,500 ft RA 이하 (POM 8.3)

🚨 LIMITATION

“Windshear avoidance/escape maneuver shall be immediately initiated if a windshear aural/visual alert occurs.” (POM 8.3)

Memory Items 🔴 (POM 8.3)

🚨 MEMORY ITEMS — MUST BE COMPLETED FROM MEMORY

PF:

1. Call “WINDSHEAR TOGA”
2. Disconnect autopilot
3. Push either TO/GA switch
4. Aggressively apply maximum thrust
5. Disconnect autothrottle(s)
6. Simultaneously roll wings level and rotate toward initial pitch attitude 15°
7. Retract speedbrakes
8. Follow flight director TO/GA guidance (if available)

PM:

1. Call “MAX THRUST, SPEEDBRAKES DOWN”
2. Verify maximum thrust is set and speedbrakes are retracted
3. Verify all required actions have been completed and call out any omissions

흐름 요약 (POM 8.3)

flowchart TD
    A[Windshear Alert 발생] --> B{Alert 유형?}
    B -- "PWS Caution: MONITOR RADAR DISPLAY" --> C[Maneuver as required to avoid]
    B -- "PWS Warning: WINDSHEAR AHEAD" --> D{Phase?}
    B -- "EGPWS Reactive: WINDSHEAR siren" --> F[Windshear Escape Maneuver 즉시 수행]
    B -- "Unacceptable flight path deviation" --> F
    D -- "Takeoff roll, prior to V1" --> E[Reject Takeoff]
    D -- "Takeoff roll, after V1" --> F
    D -- "Approach: GO-AROUND WINDSHEAR AHEAD" --> G{Pilot discretion}
    G -- "Escape" --> F
    G -- "Normal G/A" --> H[Normal Go-Around]
    F --> I["PF: WINDSHEAR TOGA, A/P off, TO/GA, Max thrust, Wings level, Pitch 15°, Retract speedbrakes"]
    I --> J{Autopilot 사용?}
    J -- Manual --> K["Follow F/D TO/GA guidance if available, Do not exceed PLI"]
    J -- Automatic --> L["Verify TO/GA mode, GA thrust advancing, Monitor system performance"]
    K --> M["Do not change gear/flap until WS no longer a factor, Wings level, Do not chase airspeed"]
    L --> M

Reference Steps (POM 8.3)

Windshear Caution (POM 8.3)

Predictive windshear caution alert: “MONITOR RADAR DISPLAY” aural (POM 8.3)

PF	PM
Maneuver as required to avoid the windshear

Windshear Warning — Takeoff Roll (POM 8.3)

Predictive windshear warning: “WINDSHEAR AHEAD, WINDSHEAR AHEAD” aural (POM 8.3)

• Prior to V1 → reject takeoff (POM 8.3)
• After V1 → perform Windshear Escape Maneuver (POM 8.3)

Windshear encountered during takeoff roll (POM 8.3):

• Prior to V1: 정지 거리 부족할 수 있음. VR에서 normal rate로 15° pitch로 rotate → airborne 후 Escape Maneuver (POM 8.3)
• Normal rotation speed 근처에서 airspeed 급감 시: 남은 활주로로 재가속 불가 → 활주로 끝 2,000 ft 전에 normal rotation 개시 (airspeed 낮더라도). Higher than normal attitude 필요할 수 있음. Maximum thrust 확보 필수 (POM 8.3)

Windshear Escape Maneuver — Manual Flight (POM 8.3)

PF	PM
Call “WINDSHEAR TOGA”	Call “MAX THRUST, SPEEDBRAKES DOWN”
Disconnect autopilot	Verify maximum thrust set, speedbrakes retracted
Push either TO/GA switch	Verify all actions completed, call out omissions
Aggressively apply maximum thrust
Disconnect autothrottle(s)
Simultaneously roll wings level, rotate toward 15° pitch
Retract speedbrakes
Follow F/D TO/GA guidance (if available)

Windshear Escape Maneuver — Automatic Flight (POM 8.3)

PF	PM
Call “WINDSHEAR TOGA”	Call “MAX THRUST, SPEEDBRAKES DOWN”
Press either TO/GA switch	Verify GA thrust set, speedbrakes retracted
Verify TO/GA mode annunciation	Verify all actions completed, call out omissions
Verify thrust advances to GA thrust	Monitor vertical speed and altitude
Retract speedbrakes	Call out trend toward terrain contact, descending flight path, or significant airspeed changes
Monitor system performance

Post-Maneuver (POM 8.3)

• Do not change gear or flap configuration until windshear is no longer a factor (POM 8.3)
• Maintain wings level to maximize climb gradient (obstacle clearance 필요 시 turn 가능) (POM 8.3)
• Monitor vertical speed and altitude (POM 8.3)
• Do not attempt to regain lost airspeed until windshear is no longer a factor (POM 8.3)

💡 PITCH LIMIT

“The pitch attitude that results in intermittent stick shaker or initial buffet is the upper pitch attitude limit. Flight at intermittent stick shaker may be required to obtain positive terrain separation.” (POM 8.3) — 15° 이상 pitch 필요 시 stick shaker/buffet가 상한. Smooth, steady control로 pitch overshoot 및 stall 방지

Note: Maximum thrust — EEC normal mode에서 thrust lever full forward로 획득 가능. Terrain contact 임박 시 thrust lever full forward (POM 8.3, Note 4)

Note: Do not exceed the Pitch Limit Indication (POM 8.3, Note 5)

Note: TO/GA 불가 시 → autopilot + autothrottle disconnect → manually fly (POM 8.3, Note 6)

🚨 LIMITATION

“Severe windshear may exceed the performance capability of the AFDS. The pilot flying must be prepared to disconnect the autopilot and autothrottle(s) and fly manually.” (POM 8.3, WARNING 7)

Unacceptable Flight Path Deviations (POM 8.3)

1,000 ft AGL 이하에서 아래 기준 초과 시 windshear로 인식 (POM 8.3):

• ±15 kt indicated airspeed
• ±500 FPM vertical speed
• ±5° pitch attitude
• 1 dot glideslope displacement
• Unusual thrust lever position for a significant period of time

💬 COMM

“Always report windshear to appropriate ATC facilities and include the term PIREP.” (POM 8.3)

QRH — WINDSHEAR SYS (QRH 15.7)

Condition: A windshear system fault occurs (QRH 15.7)

Note: Some or all windshear alerts are not available. Windshear alerts that occur are valid (QRH 15.7).

FCOM — System Background (FCOM 15.10, 15.20)

Predictive Windshear (PWS) (FCOM 15.10, 15.20)

Weather radar 기반 전방 windshear 탐지 시스템 (FCOM 15.10):

• 탐지 범위: ±40° (windshear display), 전방 5 NM (FCOM 15.10)
• 작동 고도: 2,300 ft AGL 이하 자동 작동, alert는 1,500 ft AGL 이하 (FCOM 15.10)

Alert 단계 (FCOM 15.10):

고도	Alert	Aural	Display
1,500–1,200 ft AGL	Advisory	없음	Windshear Icon on ND
1,200–50 ft AGL	Caution	”MONITOR RADAR DISPLAY”	Amber WINDSHEAR + Icon on ND
1,200–50 ft AGL	Warning (T/O)	“WINDSHEAR AHEAD, WINDSHEAR AHEAD”	Red WINDSHEAR on ND
1,200–50 ft AGL	Warning (App)	“GO-AROUND, WINDSHEAR AHEAD”	Red WINDSHEAR on ND

Note: Radar OFF 상태에서 windshear 감지 시 → system 자동 ON, amber caution light + ICON + audio 발생 (FCOM 15.10)

Reactive Windshear (GPWS) (FCOM 15.20)

실제 windshear 조우 시 감지:

• Two-tone siren + “WINDSHEAR, WINDSHEAR, WINDSHEAR” — 1,500 ft RA 이하 (POM 8.3)
• PFD: Red WINDSHEAR, Master WARNING light (FCOM 15.10)

AFDS Windshear Recovery (FCOM 4.20)

• TO/GA → pitch-up 15° or slightly below pitch limit (whichever lower) (FCOM 4.20)
• Rate of climb 증가 시 → pitch에서 airspeed control로 전환 (FCOM 4.20)
• Target airspeed: IAS/MACH window speed or current airspeed 중 큰 값 (FCOM 4.20)
• Autopilot 미사용 시 → F/D command 따라 수동 비행 (FCOM 4.20)

Precautions — Windshear Suspected (POM 7.1)

Windshear 의심 시 사전 조치:

Takeoff (POM 7.1):

• Full rated takeoff thrust 권고 (fixed derate dispatch 요구 제외) (POM 7.1)
• Flaps 20 최적 (obstacle/climb gradient 제한 시 Flaps 15도 거의 동등 성능) (POM 7.1)
• 가장 긴 적합 활주로 사용 (known windshear 지역 회피) (POM 7.1)
• 이륙 후 flight director 사용 (POM 7.1)
• VR 증가 고려: performance limited gross weight rotation speed, actual gross weight Vr + 20 kt 이하. Vr 도달 전 windshear 조우 시 → adjusted Vr까지 가속 시도하지 말고 즉시 rotate (POM 7.1)
• All-engine initial climb pitch attitude 숙지. Normal rate로 해당 attitude로 rotate. Stick shaker 전까지 pitch 감소 최소화 (POM 7.1)
• Airspeed fluctuation 주시 — windshear 최초 징후일 수 있음 (POM 7.1)

Approach (POM 7.1):

• Flaps 25 또는 30 사용 (POM 7.1)
• 1,000 ft above airport 이상에서 stabilized approach (POM 7.1)
• A/T disengage 시 airspeed correction 추가 (gust correction과 동일 방식, 최대 +15 kt) (POM 7.1)
• 급격한 airspeed 증가에 large thrust reduction/trim change 금지 (POM 7.1)

Cross-References

• Crosswind Takeoff (FCTM 3.12) — 측풍 이륙 기법, crosswind + windshear 동시 상황 시 rolling takeoff 및 VR 증가 고려
• Takeoff Weather Minima (REF) — 이륙 기상 최저치, wind limitation
• Airspeed Unreliable (QRH) — WINDSHEAR SYS checklist를 수행하지 않는 조건 (AIR DATA SYS 고장 시)