Mayday
International radiotelephony distress signal used to indicate a grave and imminent threat requiring immediate assistance.
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Emergencies
Browse Emergencies terms for pilots, air traffic controllers, cabin crew and aviation learners.
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Pan-Pan
International urgency signal indicating a situation requiring assistance but not immediately life-threatening.
View termTCAS回避指示
An instruction issued by the aircraft's TCAS system to avoid potential collision with another aircraft, advising a vertical maneuver.
View termアビオニクスベイの煙
Smoke detected in the avionics bay, indicating potential fire or overheating of electronic components, requiring immediate response and system isolation.
View termウインドシア回避操作
A predefined and trained maneuver to escape from windshear conditions during takeoff or landing.
View termエンジン分離
A catastrophic in-flight event where the engine detaches from the aircraft structure, requiring immediate emergency handling.
View termエンジン故障
A condition where one or more aircraft engines cease to provide thrust, requiring immediate emergency procedures.
View termエンジン火災消火ボトル
A pressurized container installed in aircraft engines used to release extinguishing agent when a fire is detected.
View termオルタネートコントロールモード
A degraded mode in fly-by-wire aircraft providing limited flight envelope protections, used when normal law is lost due to system faults.
View termクイックリファレンスマニュアル
A cockpit manual containing condensed checklists and procedures for abnormal and emergency situations.
View termスティックシェーカー作動
The activation of a device that rapidly vibrates the control column to warn the pilot of an impending aerodynamic stall.
View termダイレクトコントロールモード
A degraded flight control mode in fly-by-wire aircraft where control surfaces respond directly to pilot input without flight envelope protection.
View termダブルエンジン故障
A critical emergency situation where both engines of a multi-engine aircraft cease functioning in flight.
View termテールストライク
An incident in which the tail of the aircraft contacts the runway surface during take-off or landing due to excessive pitch attitude.
View termトランスポンダーコード7700
The ATC transponder code universally set to indicate a general emergency, alerting controllers to an onboard emergency situation.
View termハイジャック
The unlawful seizure of an aircraft by an individual or group, often involving threats or force, during any phase of flight.
View termバッテリーのみの電源
A condition where the aircraft’s electrical system is operating solely on battery power, typically due to the failure of all generators or external power sources.
View termバードストライク
A collision between an aircraft and one or more birds, often occurring during takeoff or landing and potentially affecting flight safety.
View termピトー管の氷結
Ice formation in the pitot tube, which can obstruct accurate airspeed measurement, potentially leading to unreliable or erroneous cockpit indications.
View termブリードエア漏れ
An unintended escape of high-pressure air from the aircraft bleed air system, which may affect pressurization, anti-ice, or environmental control systems.
View termブレーキの過熱
A situation in which the aircraft's braking system exceeds safe operating temperatures, potentially reducing effectiveness or causing damage.
View termブレースポジション
A body position adopted by passengers and crew to minimize injury during an imminent impact or emergency landing, as per operator instructions.
View termラダーの完全偏向
A condition in which the rudder deflects fully to one side due to system failure or malfunction, potentially causing severe yaw deviation.
View termラムエアインレット
An air intake system that uses forward motion of the aircraft to force external air into ducts for ventilation or pressurization.
View termラムエアインレットドア故障
A malfunction where the ram air inlet door fails to open or close properly, affecting ventilation and cooling of avionics or cabin systems.
View termランディングギアドアが開いている
A situation where the landing gear doors remain open after gear extension or retraction, indicating a potential malfunction or aerodynamic hazard.
View term不法介入
An act of unlawful seizure, threat or attack against an aircraft, its passengers, crew or ground infrastructure that endangers aviation safety.
View term与圧喪失
A condition in which an aircraft's cabin fails to maintain the required pressure differential compared to the outside atmosphere.
View term両エンジン停止
A critical emergency in which both engines of an aircraft stop producing thrust due to flameout, often requiring immediate gliding and restart procedures.
View term乗員による酸素マスクの使用
The action taken by flight crew to don oxygen masks during situations such as smoke, fumes, or cabin depressurization.
View term乗客用酸素マスクの展開
The automatic or manual release of oxygen masks for passengers in response to cabin depressurization or smoke.
View term予備計器システム
An independent set of basic flight instruments that provide critical information in case of primary display failure.
View term代替ブレーキシステム
A backup braking system used when the primary brake system fails or becomes unavailable.
View term低燃料状態
A condition where the fuel remaining is less than planned final reserve but not yet an emergency.
View term保安検査
An official inspection of an aircraft or passengers by security personnel to ensure no security threats are present.
View term信頼できない対気速度
A condition where the airspeed readings provided by the pitot-static system are incorrect or inconsistent, potentially leading to hazardous flight control inputs.
View term化粧室の煙探知
An alert triggered by smoke sensors in the aircraft lavatory indicating possible fire, requiring immediate cabin crew and cockpit response.
View term医療緊急事態
A critical health-related situation on board requiring immediate attention and possible diversion to the nearest suitable airport.
View term地形認識警報
A warning generated by aircraft systems indicating proximity to terrain that may result in controlled flight into terrain (CFIT).
View term地表接近警報システム
An onboard system that alerts pilots if the aircraft is in immediate danger of flying into the ground or an obstacle.
View term失速警報
An alert that warns the pilot of an impending aerodynamic stall, usually through audible or tactile signals like a horn or stick shaker.
View term客室安全確認
A safety verification by cabin crew to ensure passengers are seated, seat belts fastened, cabin items stowed, and emergency equipment is ready before take-off or landing.
View term客室減圧
A sudden or gradual loss of cabin pressure, requiring immediate response such as emergency descent and oxygen use.
View term客室緊急脱出
An emergency procedure where passengers and crew exit the aircraft rapidly using all available exits, typically initiated after landing or in a critical situation.
View term急減圧
A sudden and unexpected loss of cabin pressure, requiring immediate descent and use of supplemental oxygen.
View term意図しないラダー入力
An unintentional or spontaneous rudder movement not initiated by the pilot, potentially affecting aircraft yaw stability and directional control.
View term手動ランディングギア展開
The deployment of the aircraft's landing gear using a non-powered, manual backup system in the event of hydraulic or electrical failure.
View term救命いかだの使用
The procedure of deploying and utilizing inflatable life rafts by crew and passengers following a water landing, in accordance with emergency protocols.
View term救急キット
A collection of supplies and equipment for use in giving first aid in case of minor injuries or medical needs onboard.
View term時間的に重要なチェックリスト
A checklist containing emergency procedures that must be executed immediately to prevent loss of control or further danger.
View term最少燃料
A state where an aircraft’s fuel supply has reached minimum landing level; any additional delay may lead to emergency.
View term機内煙
Presence of smoke in the passenger or flight deck cabin, indicating potential fire requiring immediate attention.
View term水上着陸
An intentional or emergency landing of an aircraft on a body of water due to operational necessity or system failure.
View term水上緊急着陸訓練
A procedure practiced by cabin crew and passengers for emergency water landings, including life vest use, brace position, and evacuation steps.
View term油圧システムの故障
A malfunction in the aircraft's hydraulic system, potentially affecting control surfaces, landing gear, or brakes.
View term油圧システム二重喪失
A simultaneous failure of two independent hydraulic systems on an aircraft, significantly degrading control and operational capability.
View term油圧過熱
A condition in which the aircraft hydraulic system exceeds its normal operating temperature limits, potentially leading to system degradation or failure.
View term滑走路進入
Any occurrence at an aerodrome involving the incorrect presence of an aircraft, vehicle, or person on the protected area of a surface designated for the landing and take-off of aircraft.
View term滑走路逸脱
An incident where an aircraft veers off or overruns the runway surface during take-off or landing.
View term激しい乱気流
Turbulence causing large, abrupt changes in altitude and/or attitude, usually resulting in momentary loss of control and difficulty in maintaining aircraft control.
View term火災警報
Automated alert indicating detection of fire or overheat in an aircraft system area, requiring immediate crew action.
View term煙訓練
A practiced emergency procedure used by flight or cabin crew to respond to smoke or fire in the aircraft.
View term燃料の不均衡
A condition in which there is a significant difference in the quantity of fuel between the left and right tanks, potentially affecting aircraft stability or flight performance.
View term燃料クロスフィード
A procedure that allows fuel to be transferred from one tank to another, typically to correct a fuel imbalance or supply an engine when a tank is low.
View term燃料緊急事態
A condition where an aircraft’s fuel state is such that without immediate landing, safe completion of flight is doubtful.
View term爆弾の脅威
A reported or suspected presence of an explosive device on board an aircraft or within the airport area.
View term異常事態チェックリスト
A predefined checklist used by pilots to address abnormal but not emergency situations.
View term異常制御モード
A rare fallback flight control law in fly-by-wire aircraft used under severe system failures where no flight envelope protections are available and handling characteristics are degraded.
View term異常手順
A specific set of steps followed by pilots to address system malfunctions or unusual situations not classified as emergencies.
View term着陸装置の故障
A failure in the aircraft's landing gear system preventing proper extension or retraction.
View term破裂したタイヤ
A condition where an aircraft tyre bursts during taxi, take-off, or landing, possibly affecting braking or steering.
View term空調パックの遮断
An automatic or commanded shutdown of an air conditioning pack due to overtemperature, overpressure, or system fault, impacting cabin environmental control.
View term緊急水上着陸
The controlled emergency landing of an aircraft on water.
View term緊急降下
A rapid descent initiated by flight crew in response to a pressurization failure, smoke, or other onboard emergency.
View term翼上非常口の使用
The operation of over-wing emergency exits by passengers or crew during evacuation procedures, usually in the case of land or water evacuations.
View term脱出スライドの展開
The act of activating and extending the inflatable escape slide on an aircraft to facilitate emergency evacuation.
View term自動体外式除細動器
A portable device used to deliver an electric shock to restore normal heart rhythm during sudden cardiac arrest on board.
View term落雷
A direct or indirect electrical discharge from the atmosphere to an aircraft, potentially causing damage to avionics, surfaces, or structural systems.
View term補助動力装置の火災
A fire involving the auxiliary power unit, typically located in the aircraft's tail, requiring immediate shutdown and fire suppression.
View term規律を乱す乗客
A passenger whose disruptive or violent behaviour interferes with the safety or order of the flight and crew instructions.
View term記憶項目
A set of critical procedures that flight crew must perform from memory during certain emergencies without consulting checklists first.
View term貨物室火災
A detected or suspected fire in the aircraft's cargo hold, requiring immediate fire suppression and emergency procedures.
View term遭難救助用ビーコン
A portable beacon transmitting a distress signal for search and rescue, sometimes used interchangeably with ELT in aviation.
View term遭難救助用送信機
A radio beacon automatically activated to transmit a distress signal, assisting search and rescue in locating an aircraft in distress.
View term部分計器飛行
Flight conducted with limited or failed cockpit instruments, typically requiring reliance on backup or standby indicators for basic attitude, navigation, or altitude references.
View term離陸中止
A procedure in which a take-off is intentionally aborted by the flight crew after the aircraft has started to roll but before it has lifted off the runway.
View term静圧孔の閉塞
An obstruction in the static pressure port of an aircraft, leading to erroneous altitude, airspeed, and vertical speed indications, potentially affecting flight safety.
View term飛行中の着氷
The buildup of ice on aircraft surfaces during flight due to supercooled water droplets freezing on contact, which can impair performance or control.
View term飛行制御装置の詰まり
A condition in which the aircraft's primary or secondary flight control surfaces become unresponsive or stuck due to mechanical failure or obstruction.
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