Work out crew rest requirement instantly with clear inputs, formula shown and shareable results.
Rest must be at least as long as the preceding duty period, subject to a minimum floor, with extra rest when several time zones have been crossed because circadian adaptation lags. This models that structure so a roster can be sanity-checked before the formal legality check.
Rest requirement
Rest = max(floor, preceding duty) + 1 h per time zone beyond three
Aviation results are planning estimates only. Always verify take-off, landing, fuel, weight and balance figures against the certified Aircraft Flight Manual, current performance charts and applicable aviation regulations before flight.
Rest normally starts after post-flight duties end and finishes when the next report time begins, so travel and hotel check-in eat into it.
The body clock shifts about one hour per day, so crossing many zones leaves the crew operating at a circadian low unless extra rest is given.