Flight and Duty Time Limitations - ATPL 070 — Operational Procedures

The module closes with the subpart that keeps its people awake: flight and duty time limitations and rest requirements for aircrew in commercial air transport with aeroplanes. The science of why fatigue kills belongs to the Human Performance course; the numbers that stop rosters from causing it are here, resting on the operator's standing duties: rosters published in advance, 14 days in the guidance, duty patterns that respect sleep, and a schedule that is changed when actual operations bust the maximum flight duty period on more than a third of a seasonal schedule's flights.

The vocabulary of tiredness

The subpart runs on defined terms, and the exam quotes them. The flight duty period starts when a crew member reports for a duty that includes a sector or series of sectors and ends when the aircraft finally comes to rest with engines shut down after the last sector flown as operating crew. Flight time is block to block: first movement for take-off until rest on the parking position with engines shut down. Duty is any task performed for the operator, flying, paperwork, training, positioning and some elements of standby, and a duty period runs from report to free-of-all-duties, post-flight work included. A rest period is continuous, uninterrupted time free of all duties, standby and reserve.

Standby — a pre-notified, defined period of availability for an assignment without an intervening rest period; at the airport it is airport standby, at home or in suitable accommodation it is other standby.
Reserve — availability for an assignment notified at least 10 hours in advance, the notice period being the whole difference from standby.
Home base — the operator-assigned location where duties normally start and end, and where the operator does not owe the crew member accommodation.
Augmented flight crew — more than the minimum crew, so that each member can leave the post for in-flight rest and be replaced by another qualified member; the rest facility is a bunk, or a seat with leg and foot support.
Window of circadian low — 02:00 to 05:59 in the time zone the crew member is acclimatised to; a night duty encroaches 02:00 to 04:59; a local night is 8 hours falling between 22:00 and 08:00.
Disruptive schedule — a roster of early starts, late finishes or night duties that eats the optimal sleep window, its early type starting 05:00 to 05:59 or finishing 23:00 to 01:59, its late type starting 05:00 to 06:59 or finishing 00:00 to 01:59.
Acclimatised — synchronised to a 2-hour-wide time zone band; a crew member stays acclimatised to the reference time for just under 48 hours after reporting, and beyond that a table of time-zone difference against elapsed time decides between the departure zone, the new zone, and an unknown state.

The daily limit

The basic maximum daily flight duty period is a table with two axes: report time and sectors. Its best cell is 13 hours, for an acclimatised crew member reporting between 06:00 and 13:29 for one or two sectors. From the third sector each further sector costs 30 minutes, later and earlier report times walk the limit down in 15-minute bands to a worst basic value of 11 hours for reports between 17:00 and 04:59, and the whole table floors at 9 hours. A crew member in an unknown state of acclimatisation starts from 11 hours, or 12 hours where the operator runs a fatigue risk management system that keeps watching the outcome. One cabin-crew wrinkle: when the cabin crew report earlier than the flight crew for the same sectors, their FDP may be longer by the reporting difference, capped at 1 hour, the limit still computed from the flight crew's report time.

The cumulative clocks

Above the daily table run the cumulative limits. Duty is capped at 60 hours in any 7 consecutive days, 110 hours in any 14, and 190 hours in any 28, spread as evenly as practicable. Flight time as operating crew is capped at 100 hours in any 28 consecutive days, 900 hours in any calendar year, and 1,000 hours in any 12 consecutive calendar months, the rolling window that stops two calendar years being stacked back to back. Post-flight duty counts as duty, positioning at the operator's behest counts as duty in full, and positioning after reporting but before operating counts as FDP without counting as a sector. The operator keeps individual records of flight times, duty and rest for 24 months.

Stretching the day

The basic table can be stretched three ways, and the first of them combines with neither of the others in the same duty. Without in-flight rest, the maximum daily FDP may be extended by up to 1 hour, at most twice in any 7 consecutive days, planned in advance, paying for itself in rest: 2 hours more on both the pre-flight and post-flight rest, or 4 hours more after the flight. The extension is capped by the circadian window: 5 sectors when the window of circadian low is untouched, 4 when it is encroached by up to 2 hours, and only 2 sectors when the encroachment is deeper. With in-flight rest the extension comes instead from the operator's flight time specification scheme under the certification specifications, priced by four factors: the sectors flown, the minimum in-flight rest per crew member, the class of rest facility, and the augmentation of the crew; the resting pilot remains operating crew and the rest counts in full as FDP, and the cabin-crew lesson's in-flight-rest reduction hangs off the same machinery. The third stretch is split duty: a break on the ground may extend the day per the scheme, the break counting in full as FDP, and split duty never follows a reduced rest.

The commander's discretion

When unforeseen circumstances begin at or after the reporting time, the limits bend at the commander's discretion, inside hard edges: the maximum daily FDP may grow by at most 2 hours, or 3 hours with an augmented flight crew; if the allowance is exceeded on the final sector by circumstances arising after take-off, the flight may continue to the planned destination or alternate; and the following rest may be reduced but never below 10 hours. Discretion cuts both ways: facing severe fatigue, the commander shall reduce the FDP or increase the rest instead. Before deciding either, the commander consults all crew members on their alertness; afterwards a report goes to the operator, and when the stretch or the cut exceeds 1 hour, the operator adds its comments and sends the report to the competent authority within 28 days. The whole mechanism lives inside a non-punitive process described in the operations manual, and the guidance expects it to stay exceptional, especially at home base and hubs where standby crews wait.

Standby and reserve

Standby is rostered, with its start and end notified in advance. Airport standby runs from reporting to the end of the notified period and counts in full as duty period for the cumulative and rest rules, with the operator providing accommodation; any actual duty at the airport counts in full with the FDP running from that reporting. For other standby, at home or in suitable accommodation, the flight time specification scheme prices everything: the maximum duration of any standby, its effect on the FDP that may follow, the rest after a standby that brings no assignment, and how the hours count cumulatively. Reserve is the gentler cousin: rostered availability whose assignment arrives at least 10 hours ahead, leaving a protected sleep opportunity, with the scheme setting the maximum single reserve period and the consecutive reserve days; a reserve day that brings no duty cannot retroactively be relabelled recovery rest.

Rest

The rest floors mirror the geography. Before an FDP starting at home base, rest is at least as long as the preceding duty period, and never less than 12 hours; away from base the floor is 10 hours, but with an 8-hour sleep opportunity inside it on top of travelling and physiological needs, the guidance pricing physiology at 1 hour and adding twice any travel beyond 30 minutes. An operator that houses its crew in suitable accommodation at home base may apply the away-from-base rest there, the back-to-back roster. Cumulative fatigue is drained by the recurrent extended recovery rest: at least 36 hours including 2 local nights, never more than 168 hours from the end of one to the start of the next, and grown to 2 local days twice every month. Reduced rest exists only inside the specification schemes, with a longer rest and a shorter FDP to follow, and even the meals are law: an opportunity to eat and drink whenever the duty runs long, especially past 6 hours of FDP.