Abnormal and Emergency Operational Procedures
This domain tests the distinction between abnormal and emergency, the correct distress/urgency call, and the sequence of actions from memory items to checklist.
Definitions and signals
Distress is a condition of being threatened by serious and imminent danger requiring immediate assistance: MAYDAY, three times, with the transponder on 7700. Urgency is a condition concerning safety but not requiring immediate assistance: PAN PAN. Communications failure is 7600 and unlawful interference 7500. ATC declares an emergency phase when it loses contact or receives an urgency signal.
Handling emergencies
Memory items (for example, for rapid depressurisation, engine fire, smoke) are actioned first, then the QRH checklist is read. The commander retains authority, declares the emergency to ATC, requests priority and states intentions. Time available is the controlling factor in decisions to divert.
Specific situations
Pressurisation failure: oxygen masks, establish communication, initiate emergency descent to the lower of 10,000 ft or MSA, turn off track, then assess. Engine failure after V1: continue, climb to a safe altitude, then identify and secure. TCAS resolution advisory: respond immediately to the command, even outside a clearance, and notify ATC. GPWS: maximum performance climb. Fire or smoke: land as soon as possible; evacuation only when the situation demands it. Ditching follows the ditching checklist and cabin preparation.
Reporting
Any serious incident or emergency must be reported through the operator's safety system and to the authority; dangerous goods incidents and unruly passenger events have dedicated reporting routes.
Worked example
Rapid depressurisation at FL370: don oxygen masks, establish crew communication, set 7700, start emergency descent and turn off the assigned track, advise ATC, level at 10,000 ft or MSA, then work the QRH.
Traps that cost marks
Using PAN PAN when the situation requires MAYDAY; delaying oxygen to advise ATC first; following a TCAS RA only with ATC approval; reading the QRH before the memory items.