Goal

To have the most alert crew in the control seats for the critical phases of flight (takeoff, descent, approach, and landing).

Overview

This document provides long range augmented crews information for developing effective in flight crew rest strategies. The information outlined in this guide, combined with sound operational experience, will provide each crewmember the tools necessary to develop a plan to mitigate fatigue, and enhance pilot alertness.

Introduction

A wide range of scientific investigation and discussion exists regarding the effect of sleep and fatigue on pilot performance. The key to successful fatigue mitigation is to combine scientifically supported principles with operational experience - in addition to what we know about ourselves as individuals - to craft a plan that is appropriate for the operation we are performing today. The facts presented in this publication are taken from the most up-to-date scientific data available combined with experience from other long haul international airlines and our own operational experience.

Terminology

The fatigue mitigation terminology defined below is referred to frequently in this guide.

Window of Circadian Low (WOCL) :

Humans are hard-wired to experience two periods of physiological sleepiness each day, at about 0200-0600 (body time) and 1400-1800 (body time). These sleepy times are dictated by the circadian biological clock (pacemaker) in the brain that modulates the way people function and feel, in step with the day/night cycle. The peak in sleepiness in the early hours of the morning is commonly known as the Window of Circadian Low (WOCL). The mid-afternoon peak in sleepiness is commonly known as the Afternoon Nap Window

Time of Continuous Wakefulness

Continuous wakefulness refers to the amount of time since an individual last slept. As time of continuous wakefulness is prolonged because of long duty periods or inability to sleep, performance and vigilance deteriorate.

Landing Pilots :

Designated by the Pilot in Command in the preflight briefing, the landing pilots are the pilots who will be in the control seats no later than 45 minutes prior to landing through the shutdown checklist completion.

Relief Pilots :

The relief pilots are the ones not designated to make the landing. Their function is to help maximize alertness for the landing pilots, commensurate with their duties while in the control seats.

Short, Secondary Rest Break :

A rest break used primarily on flights over 12 hours block time to mitigate the fatigue associated with extended periods of time in a control seat (4 hours or more time on task) prior to landing, to be completed and at the controls no later than 45 minutes prior to landing.

Facts

Preflight

1. Report for the trip as well rested as possible. A monthly schedule (which takes into account FARs and the CBA) combined individual responsible behavior will provide ample opportunity to obtain proper rest.
2. An afternoon nap prior to an evening report will be very beneficial since the amount of sleep achieved onboard the aircraft is generally not related to the amount of sleep received in the previous 24 hours. This is also important because sleep in the bunk is generally of lesser quality than sleep in a hotel or at home.
3. Attempting to limit preflight sleep to prepare for bunk sleep is shown to be ineffective and decreases the total sleep obtained during the flight. It is also risky, because good sleep in the bunk cannot be guaranteed.

During Flight

1. All possible break scenarios should be evaluated. In most cases, a key goal is for the landing pilots to get a long break at a time when they would normally be sleeping 0200-0600 (body time). If the flight does not operate during the 0200-0600 (body time) window, the next optimal time for sleep is 1400-1800 (body time).
2. Break lengths and patterns should be based on current science as well as operational experience. Consideration should be giving to limiting time of continuous wakefulness. See the examples shown in this document.
   
3. Operational experience shows:
   • Minimum break length for restorative sleep is two hours.
   • Maximum break length to provide the greatest amount of sleep and optimum utility for the overall scenario is four hours.
4. For flights over 12 hours block time, it is strongly recommended that a four break scenario be used. This provides a second oportunity to sleep in the event that no or little sleep was obtained during the first rest opportunity. It also mitigates numerous other factors mentioned in this section.
5. Recent studies suggest that flight crews are able to sleep for about half their available rest time in a four break scenario.
6. The amount of sleep obtained in flight is dependent on the time of the day (body time). More on-board sleep will be obtained during normal sleep times (body time).
7. If operational factors prevent following the recommended times in the examples, it is very important to schedule significant breaks during normal (body time) WOCL (0200-0600) or normal (body time) afternoon nap window (1400-1800) and to sleep as much as possible during these scheduled breaks.
8. Recent research suggests that when using a 4 break rest pattern, sleeping during both rest breaks results in more total in-flight sleep than only trying to sleep in one rest break. Sleeping in the first rest break did not reduce the amount of sleep obtained in the second rest break.
9. Turbulence is the most commonly cited factor disturbing sleep in flight.
10. Consume meals during periods of flight deck duty. It is imperative to spend as much of the scheduled rest time as possible attempting to sleep.
11. Mitigating lengthy periods in a control seat prior to landing, especially for flights over 12 hours block time and/or 4 hours or more time on task is critical. Landing pilots scheduled to be in a control seat longer than 4 hours prior to the landing will normally be provided a short, secondary rest break to be completed no later than 1 hour prior to the landing. A 20-45 minute nap (or longer if able) is the most effective mitigation. The pilots not occupying the control seats for landing will be available to provide this break and should, at a minimum, provide enough time for a 20-45 minute nap or something similar.

Layover

1. Obtain as much sleep as possible while on the layover. Attempt to get at least eight hours in a 24 hour period. The eight hours of sleep doesn’t need to be in one block (split sleep), as long as a significant amount was obtained at a time where you would normally be sleeping (body time). For instance, four hours sleep at 0200-0600 (body time) and four hours at a different time can be almost as effective as a single eight-hour block. Split sleep is common, especially after long flights crossing multiple time zones or multiple day pairings.
2. Naps should be up to three hours in length. Sleeps should be four or more hours in length.
3. Once away from home, time zone adaptation will begin to occur. In other words, a pilot’s body time will begin shifting towards the local time zone (your current location). Scientific data does not provide definitive guidance on the rate at which this occurs. However, a good rule of thumb, especially during multiple day trips, is to “sleep when you’re tired” until four or more days in the local time zone. After that, use the new timezone to estimate your body time.
4. People over age 50 do not need less sleep than younger people. Rather, they tend to have more difficulty getting long periods of consolidated sleep, so they may need to allow more time for sleep during layovers.
5. If asked to stay at the hotel past pick-up time, or if sent back to the hotel after reporting, attempt to get some sleep during this rest opportunity. Even if it’s only a short sleep, it will increase alertness by breaking up the period of continuous wakefulness.

Recovery

FARs require a rest period at the completion of a trip. Any length of trip will require a sleep adjustment period upon return. Try to get back to normal home sleep times as quickly as possible.

IROPs/Delays/Diversions

In these situations, rest breaks at the proper physiological time are critical.

1. With the focus on the landing crew, a significant break (minimum 2+30) should be scheduled during normal sleep time 0200-0600 (body time).
2. Also, target the afternoon nap window (1400-1800 body time) for significant breaks.
3. The landing pilot(s) should make every attempt to be in the control seat no later than 1 hour prior to landing. However, during IROPs/delays/diversions where this is not possible, attempt to minimize the period of continuous wakefulness. Keep in mind that the minimum time needed to overcome sleep inertia is 20 minutes; therefore, it is imperative that the landing pilots allow enough time to overcome these effects prior to taking control of the aircraft.

Onboard Rest

Assumptions

The goal of effective use of onboard rest is to have the most alert pilots in the seat for the critical phases of flight (takeoff, descent, approach and landing).

Regulations and Guidance

How do we best match the available rest time and breaks to optimize alertness and mitigate fatigue? Think of this as a checklist to aid in developing rest break assignments.

• The Pilot in Command (Captain) is charged with the coordination of flight deck duties and rest breaks. All pilots on the crew must account for the operational and individual circumstances present for that flight on that day.
• The decision on which pilots will be in the seats for the takeoff and landing and which pilot(s) will perform the takeoff and landing will normally be designated in the preflight briefing.
• Assign the landing pilots to the optimum break in accordance with FAR 117. Pilot Flying must have a minimum of 2 consecutive hours rest in the last half of the Flight Duty Period (PDF). Pilot Monitoring needs 90 minutes anywhere in the FDP.
• Assign the remaining breaks as appropriate.
• The relief pilots' function is to help maximize alertness for the landing pilots. Seniority should not play a role in determining rest breaks. The main goal is to maximize alertness for the landing pilots.
• Rest breaks are not tied to takeoffs or landings. Rest breaks are used as tools for the landing pilots to get the job done.
• It is acceptable for pilots to perform the takeoff and then proceed immediately into the first break period if that provides the best opportunity for sleep and complies with all regulations.

Determining the Optimum Break Period

Determining the optimum rest period is a blend of science and operational experience. To illustrate this concept, several challenging flights are used as examples. The guidance provided in this document was applied to help develop different rest plans.Determining the optimum rest period is a blend of science and operational experience. To illustrate this concept, several challenging flights are used as examples. The guidance provided in this document was applied to help develop different rest plans.

As discussed earlier, scientific data supports that there are two periods during a 24-hour day when we experience a greater urge to sleep, the WOCL (0200-0600 body time) and the afternoon nap window (1400-1800 body time). Identifying when these times are likely to occur in flight is a good starting place to determine the optimum rest periods for your flight.

If your flight overlaps one or both of these periods, the goal should be to get the landing pilots into the rest facility for as much of that time as possible. Also, this may help you determine the appropriate number of rest periods you will use.

1. Multiple rest periods for each pilot are generally only used for flights over 12 hours.
2. In some cases, however, crews operating a flight approximately 12 hours in length may find the multiple rest period scheme beneficial as well.

We will assume all pilots report well rested with no extraordinary stress or pressure. Keep in mind, our main goal is to have the most alert crew possible in the control seats for the critical phases of flight.

Each route on subsequent pages includes a written explanation along with a diagram.

1. Routes requiring four pilots have three different rest break possibilities presented. Distinct advantages and disadvantages, based on the guidance provided in this guide, are highlighted.
2. Routes requiring three pilots have only one rest break option presented. realizing Three pilot crews tend to split breaks evenly unless prohibited by FAR 117, i.e total break time less then 6 hours. Most of the discussion for three pilot crews revolves around when the landing pilot should and can be on break.

Examples

EWR to BOM 4 Pilots

This is an evening departure that flies through the WOCL, so the best opportunity for restorative sleep (the optimum break for this flight) will be 0200-0600 body time. The landing pilots should have a significant break somewhere in this period. Next we need to look at the total time available for rest to see how to most effectively use that time for maximum fatigue mitigation.

ORD to NRT 4 Pilots

This is a late morning departure that flies through the afternoon nap window but lands before the WOCL. The 1400-1800 window will be the best opportunity for restorative sleep. The landing pilots should have a significant break somewhere in this period. Next we need to look at the total time available for rest to see how to most effectively use that time for fatigue mitigation.

EWR to LHR 3 Pilots

This is an early evening flight where the landing will be conducted just as the flying pilot's WOCL begins. The main concern will be limiting the time of continuous wakefulness prior to the landing. In this case, the second or third break will be optimum.

ORD to GRU 3 Pilots

This is an evening departure that flies through the entire night. The early morning WOCL falls in the latter part of the flight, ending shortly after the “1-hour prior to landing” point. The optimum rest period will be the second or third break because either fall partially within the WOCL so it provides the best opportunity for restorative sleep, as well as limits the landing pilot’s time of continuous wakefulness prior to landing.

Delays / IROPs

Since there are a myriad of scenarios that arise with delays/IROPs, no specific examples are given. Please review the guidance on scientific principles and operational experience as well as delays and IROPs earlier in this document.

Diversions

There are an infinite number of diversion scenarios possible on long international augmented flights. A challenging case is presented here to demonstrate how to apply current scientific principles and operational experience to a diversion. Please keep in mind diversions are rare. This example is designed around safety concerns. Recency, seniority or fairness issues were not and should not be considered in the instance of a diversion. The city pair is Atlanta (ATL) Mumbai (BOM) and the diversion airport is Manchester, U.K. (MAN), which is approximately half way through the flight. This example serves as a challenging scenario that has been operationally and scientifically validated.

During the preflight briefing, the Pilot in Command decided to use an equal break pattern and designated the landing pilots to take the second and fourth breaks. Taking the second break allowed the landing pilots to have a significant sleep opportunity at a time they would normally be sleeping. Taking the fourth break limits their time of continuous wakefulness prior to landing.

While the landing pilots are on their first break, a medical emergency occurs. Contact with dispatch is made and the recommendation is to divert for immediate medical attention. The crew (The relief Captain currently is in the left seat and not one of the landing pilots) decides in conjunction with the dispatcher to divert to MAN. The PIC (Captain) also decides that since the relief Captain is rested and has the best understanding of the current situation, he will perform the landing in MAN.

After a one-hour turn in MAN, three key items must be considered:

1. All pilots must maintain an adequate level of alertness throughout the remainder of the flight.
2. The landing crew must be properly rested.
3. In addition, the time of continuous wakefulness between the landing crew’s completion of the last break and the landing in BOM must be minimized.