The bold steps you do from memory, the read-do steps you do from the book — and the discipline to stop when they disagree with what the aircraft is telling you.
The idea
An emergency splits into two kinds of action. First, a short list of memory items — the immediate, do-from-memory steps that keep the aircraft safe while there’s no time to open a book. Then the QRH (Quick Reference Handbook): read-do checklists you work slowly, one challenge and one response at a time, with a partner reading each step back.
The slower second half exists to catch the mistakes the fast half can make. So when a step contradicts what you’re actually seeing, the disciplined move is to stop and reassess — not to push on because the checklist “said so.”
the QRH runner — a warning has fired on climb-out
Engine 2 (right)
Fire warning, high EGT, heavy vibration
Engine 1 (left)
All parameters normal, running
Phase
Ready
Step
0 of 7
Affected engine confirmed
Right checklist confirmed
Wrong-engine call caught
Ready
A fire warning has fired on the No. 2 engine.
Press begin to run the drill: memory items first, then the read-do QRH, challenge and response.
You fly the aircraft first, then run the drill. Watch the phase change from memory items to read-do QRH — and watch for the step that doesn’t match the symptoms.
How it works
The framework, in order — the same order a trained crew works it:
Fly the aircraft first. , navigate, communicate. Split duties: one pilot flies, the other runs the drill. The checklist never comes before flying.
Do the memory items. A short, bold list done immediately from memory — no book — because there isn’t time to read.
Confirm the right checklist. Match the annunciation to the QRH title before you start reading. Right symptom, right book.
Challenge and response. One pilot reads the challenge; the other responds, actions it, and reads it back. Nothing is skipped, and both agree on every line.
Guard the irreversible steps. Fuel cutoff, fire handle, engine shutdown — confirm the correct engine or switch with the other pilot before you move it.
Stop when it doesn’t fit. If a step or a contradicts the symptoms, halt. Re-confirm the diagnosis and that you’re on the right checklist — then continue.
When to use each half
Situation
What it calls for — and the trade-off
Time-critical, must act now (fire, stall, rapid depressurisation)
Memory items. Only a handful can be reliably memorised — keep the list short and truly bold.
Everything after the immediate threat is contained
Read-do QRH. Slower, and it needs both pilots and a stable enough moment to read.
Indications are ambiguous or contradict each other
Stop and reassess. Costs a few seconds now to avoid an irreversible wrong action.
Watch out for
Running the whole thing from memory. Memory items are a short bold list; past them, open the book. Memory drifts under stress and adrenaline.
Skipping challenge-response. Silent, solo checklist work removes the cross-check that catches the wrong switch or the missed line.
Rushing a guarded item. Fuel cutoff and fire handles are irreversible. Confirm the engine before you move it — the well-documented 1989 Kegworth accident turned on a crew reducing power on the good engine.
Pressing on through a contradiction. If the step points one way and the aircraft shows another, that is your cue to stop — not to trust the paper over your instruments.
Letting the checklist fly the aircraft. Someone must always be flying. Aviate and navigate come before finishing any line.
Worked example
An interviewer asks: “Walk me through an engine fire just after takeoff.” A strong answer keeps the order. Fly first — PF flies, PM runs the drill; call and confirm the failure. Do the memory items: affected thrust lever closed, its fuel control cutoff, fire handle pulled — and each irreversible one confirmed by both pilots as the correct engine. Then open the QRH, confirm the Engine fire checklist matches the warning, and work it challenge-response. If a step or a readback names the healthy engine, stop and re-confirm which engine failed before touching anything. Close with the follow-on: divert to the nearest suitable airport, declare, and brief the approach.
Check yourself
Mid-checklist, the step you just read points at the engine whose parameters are all normal. Best move?
Which of these belongs in memory items rather than the read-do QRH?