14 CFR 135.267 Duty Time Calculator

Checks the Part 135 flight time limits and rest requirements for unscheduled operations before you issue a release. All computation is local — nothing is sent to a server.

Flight details

Operation type

Rest period start

Duty period (FDP) start

Hours already flown in past 24h

Proposed flight time (hours)

Hours flown this calendar quarter (all commercial)

Hours flown this calendar year (all commercial)

Prior rest period135.267(d)

10h minimum (8h with DO-arranged compensatory rest)

Enter rest start and FDP start

24h flight time (single-pilot)135.267(b)

8h in any 24 consecutive hours

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Calendar quarter total135.267(a)(1)

500h in any calendar quarter (all commercial flying)

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Calendar year total135.267(a)(3)

1,400h in any calendar year (all commercial flying)

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Note on reduced rest (135.267(d)(2))

The 10-hour prior rest requirement may be reduced to a minimum of 8 consecutive hours if the certificate holder arranges a compensatory rest period of at least 10 consecutive hours immediately after the assignment ends. This calculator flags rest under 10h as a potential issue — document the compensatory rest arrangement if applying this provision.

This tool covers unscheduled on-demand operations under 135.267. Scheduled/commuter operations use 135.261–135.266, which have different limits.

Run this check automatically before every dispatch

Clearspar runs 135.267, 135.247 currency, MEL, airworthiness, and FRAT checks before every quote goes out — with a tamper-evident log of every CLEAR and UNABLE.

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