14 CFR 135.267 — Multi-day duty/rest
Multi-Day Crew Pairing Legality
Enter the crew member's starting state and each day's show/release/flight hours. Get a day-by-day CLEAR / CAUTION / UNABLE verdict — rest gaps, duty limits, flight hour caps, and quarterly totals.
Crew starting state
Default crew type
Last rest period ended (UTC) — before this trip
Trip duty periods
ILLEGAL·DUTY CLEAR·FLT CLEAR
Show (UTC)
Release (UTC)
Flight hours this duty period
Crew size this period
Duty
10h
max 14h
Flight hrs
4h
max 8h
Rest before
0h
min 10h / 8h ↓
Qtr total
4.0h
max 500h
UNABLE
One or more duty periods have a regulatory violation. See the duty periods above for the specific limiting factor.
Trip flight hours
4.0h
Qtr total after trip
4.0h / 500h
14 CFR 135.267 · 135.267(d) reduced rest · 135.267(c) 14h duty
What this means for dispatch: This crew pairing has a regulatory violation in at least one duty period. The assignment cannot legally be released under 14 CFR 135.267. The DO must revise the schedule — adjust show/release times, reduce flight hours, or reassign the crew — before dispatch.
Clearspar runs crew legality checks automatically on every quote — before it leaves your inbox →
Advisory only. Duty/rest legality is highly fact-specific. This tool checks period-level limits — it does not track intra-period 24-hour sliding windows (use Multi-Leg Duty Clock for that). Not a substitute for your Director of Operations.
Frequently asked questions
How is this different from the Multi-Leg Duty Clock?
The Multi-Leg Duty Clock checks multiple flight legs within a single duty period on the same day — tracking the 24-hour sliding flight time window. This Multi-Day Crew Pairing tool checks legality across multiple duty periods over multiple days — tracking rest between duty periods, cumulative quarterly totals, and whether the crew member can legally start each new day's assignment. Use multi-leg for intraday scheduling, crew pairing for trip-level planning.
What is the minimum rest required between duty periods?
Under 14 CFR 135.267(a), crewmembers must receive a rest period of at least 10 consecutive hours before each duty period. A reduced rest of 8 hours is permitted under §135.267(d), but only if the crewmember receives compensatory rest of at least 11 or 12 hours (depending on how short the reduced rest was) within 24 hours of the start of the reduced rest period.
What is the maximum duty period for a Part 135 crewmember?
Under 14 CFR 135.267(c), the maximum duty period is 14 consecutive hours. A duty period begins when the crewmember reports for duty and ends when released from all duties. This 14-hour limit applies regardless of single-pilot vs. two-pilot operations.
What are the quarterly and annual flight hour limits?
Under 14 CFR 135.267(b), a crewmember may not fly more than 500 flight hours in any calendar quarter or 800 hours in any two consecutive calendar months. The annual limit is 1,400 flight hours in any calendar year. These are cumulative limits — once reached, the crewmember cannot be assigned any further flight duties until the period resets.
Does the duty period start at "show time" or when the first flight departs?
The duty period begins when the crewmember reports for duty — their "show time" — not at wheels-up. Pre-flight planning, weather briefing, and aircraft preflight are all part of the duty period. Similarly, it ends when the crewmember is officially released, not at block-in.
Clearspar runs this check automatically on every quote — for every crewmember on your roster.
Trip-level duty/rest legality is computed against each pilot's actual rest history and quarterly hours, not estimated. UNABLE means UNABLE before the quote goes out.
See Clearspar