Part 135 crew rest: the 8-hour floor, the 10-hour minimum, and when you can reduce

The crew rest requirement in Part 135 is simpler to state than it is to apply in practice: after every duty period, a crew member must receive at least 10 consecutive hours of off-duty time before beginning another duty period. That is 14 CFR 135.267(d). The complexity enters with two conditions — what counts as “off duty,” and when you are allowed to use the reduced 8-hour floor.

The 10-hour minimum: what it means operationally

The 10-hour rest period must be consecutive — not accumulated across interruptions. The clock starts at actual release from duty, not at scheduled release or at the time the crew reaches the hotel. If a pilot is released at 23:30, they cannot begin their next duty period until 09:30.

The rest must also be free from duty. Time spent commuting to the hotel, waiting for crew transportation, or on-call does not count. Only time with no duty obligation counts toward the 10 hours.

The 8-hour reduced rest provision

Section 135.267(d) allows a single rest period to be reduced to 8 consecutive hours, provided all three of the following conditions are met:

1. The reduction is authorized by the certificate holder — meaning the operator must have a procedure for this in their GOM, and the DO must sanction its use.
2. The reduced rest occurs only once in any 168-consecutive-hour period (7 days rolling).
3. The crew member receives a full compensatory rest period of at least 10 consecutive hours before the next duty period after the one that followed the reduced rest. You take the short rest once; the next rest is full.

The sequence: what the logbook must show

A correctly documented reduced-rest sequence looks like this:

1. Duty period 1: ends at 23:00 on Day 1.
2. Rest: 8 hours (reduced). Crew released for duty at 07:00 on Day 2.
3. Duty period 2: ends at 18:00 on Day 2.
4. Rest: must be at least 10 consecutive hours. Crew cannot be scheduled before 04:00 on Day 3.

If the logbook shows duty period 2 starting before 07:00 on Day 2, or the compensatory rest being less than 10 hours, the rest sequence is non-compliant regardless of what the schedule said.

How a dispatch tool should handle reduced rest

A compliant dispatch system should track whether a crew member has used the reduced-rest provision in the past 168 hours. If they have, the system should enforce the full 10-hour minimum for the next rest period. If they have not, the system may allow scheduling the 8-hour minimum — but it should log the exception and surface it in the dispatch release.

In Clearspar, the compliance engine enforces the rest gap at quote time. If the proposed showtime falls within 10 hours of the crew member's last recorded duty release, the gate returns a 135.267(d) VIOLATION with the gap and the shortfall. Operators who need to use the reduced-rest provision can issue an override with a documented reason — which is logged and printed on the dispatch release.

Common misreads

• “They had 8 hours in the hotel” is not the same as 8 consecutive hours off duty. Transit time from the airport to the hotel is duty (or at least on-call) until the crew is released. Count from release, not from wheels down.
• The reduced rest is not available if the crew is over any other limit. A pilot who is within 2 hours of their 135.267(a) quarterly cap does not get extra flights by shortening the rest. All limits stack.
• OpSpecs may be stricter. If your OpSpecs require 11-hour rest or prohibit reduced rest, the OpSpecs govern. The FAR is a floor, not a permission slip.