TNO Defence, Security and Safety

TNO report

Extension of Flying Duty Period by In-flight Relief

Status: Final Draft

Date 29 July 2007

Autbor(s) Fties Símons, MD. & Miok Spencer, BA MSe.

Copy no. , ,.

No, of copies a > o < <_~._,.`.-

Number of pagcs 25

Numberofappendices 0

CUbtOmer DG Tran9port en ZUChtuaart,

 Programmx Luchtvaatt Veiligheid

Projeetname Maximmn Premissible Extension of FDP

Projectnumber 032.1.3267

Al7 dghts reserved.

No part of this pubtication may be reproduced and/or published by print, photoprint, microFim

or any other means witbout the prevíous written oonsent oP'fNO.

tn case this report was drafted on. instructions, the righls and obtigations of contractíng parties

are subject to either the Standard Conditions for Researoh Instmotions given to TNO, or the

relevant agreement concluded bctween the contracting pariies. Submitting the zeport for

inspection to parties who have a direct interest ís permitt~ed.

Avíatioo

Kampweg 5

P,O. Box 23

3769 2G Soesterberg

The Nethedands

T +31 34 635 62 11

F +31 34 635 39 77

in4o-DenV@tno.nl

C~ 2007 TNO

Scan nummer 3 van 3 - Scanpagina 1 van 25

Ingekomen stukken - 1284
TNO report

2125

M~ Contents 

Background of the project team 3

Swnmary 4

I Terms of reference 6

2 Background of the project 6

2.1 Aim of the project 7

2.2 Metltod 7

3 Requirements of max. extension of FDP of other European C;AAs 9

4 Background on sleep and alertness l 1

5 Crew rest facilities 14

5.1 Sleep in a bunk 14

5.1.1 Sleep in a crew bunk: implications for FTL 16

5.2 Sleep on the aireraft elsewhere than in a bunk 16

5.2.1 First class seat or top range business class seat 16

5.2.2 Normal business class seat 16

5.2.3 Flight deck seat - other seat that reclines at least 40° 17

5.2.4 Economy class seat 17

5.2.5 Sleep on the aircraft elsewhere than in a bunk - implications fox FTL 18

6 Swxmiary of recommendations 19

6.1 Implications for FTL 20

7 Comparison with requirements from ot3ter European countries 21

8 References 22

Scan nummer 3 van 3 - Scanpagina 2 van 25

Ingekomen stukken - 1284
TNO report

3125

Background of the project team

Siäce 1986 TNO Human Factors (until 2002 the Aeromedical Instihtte) has performed

e~Yudies into the effects of fatigue on alertness and performance of flight crew. Projects

lïäve been commissioned by natiocgal (Ministry of Transport, Ministry of Defense) and

intemational authoritíes and airlines (JAA, CAA Singapore, CAA Hong Kong, KLM,

Aer Lingus). In the context of a Fatigue Countermeasures programme, studies have

been performed of different types of flight operations (short-haul, long-haul, ultra longhaul, cargo, helicopter). Central research issues were the effects of time-zone

transitíons, night flights, in-flight and layover sleep, and efrects on alertness and

performance. Effects of different countermeasures, such as ín-flight sleep, cockpit

napping, crew augmentatíon and layover policy, have been assessed in field studies.

With the results of these studies a database has been developed which enables

determination of the relationships between ths different operational and human factors.

Since 1986, Ries Símons, MD has been the project leader of the TNO team. He is a

foundíng member of ECASS (the European Committee for Aircrew Scheduling and

Safety) and the present project is performed in close consultation with Mick Spencer,

BA MSc, who is also a founding member of ECASS. He has collaborated as an ECASS

member with the TNO team ín many studies conceming FTL issues.

For over 15 years until his retírement in 2006, Mick Spencer led a team at the QinetiQ

Centre for Human Sciences in Farnborough UK carrying out research into sleep,

circadian rhythms and fatígue. He has developed mathematical models related to the

regulation of sleep and wakefulness. Pmetical applications in this area have included the

design and development of the computer program SAFE (System for Aircrew Fatigue

Evaluation) for the assessment of duty sehedules in civil air operatíons. He is an

acknowledged expert in the field of aircrew fatigue, and has been invited to present at a

broad range of conferences and workshops, including thase organized by the Royal

Aeronautical Society, the International Federation of Aixlíne Pilots, and the Fhght

Safety Foundation. IIe sits on the Intemational Aviation Advisory Panel that reviews

the fatigue monitoring programme of Air New Zealand. Other organizations he has

advised include the C;ivil Aviation Department of Hong Kong, the Civíl Aviatíon

Authority of Singapore, Síngapore Airlines and the JAA. He designed and developed

the Fatigue Index that is currently being used by the UK Health and Safety Executive to

assess the Fatigue ímplicatíons of shift systems throughout British industry. Since his

retirement, Mick Spencer has continued to work as a consulfant to QinetiQ and to other

organizations.

Scan nummer 3 van 3 - Scanpagina 3 van 25

Ingekomen stukken - 1284
TNO report

4125

Summary

I3äsed on ËU OPS subpart Q, the Ministry of Transport of the Netherlands made a

~oncept of requirements related to the extension of the maximum flight duty period

(FDP), in case of augmentation of the cockpit crew and the availability of on-board rest

facílíties.

Aim of the pYOjecf

The Ministry of Transport commissioned 1N0 to give science-based advíce conceming

the maximum permissible extension of the FDP, related to the quality of the available

on-board rest facílity and the augmentation of the crew with one or two pilots.

Method

Relevant national and intematíonal literature and databases have been studied and

analysed, addressing the quality of the different in-flight rest facilities in relation to the

yield in terms of sleep, aleriness, and performance. Based on careful evaluation of the

evidence, recommendations have been made concerning extensions of FDP in relation

to the different rest facilitíes and the extent of augmentatíon. Areas where scientific data

were lacking have been identifred and expert judgement was used in these cases.

Outcome

In-ilight sleep periods are an effective measure ín maintaining alertness and

performance at sufficient levels throughout a long-haul flight. Alertness and

performance are better maintaíned after sleep periods of longer duration. However, the

beneflt of longer sleep periods has to be balanced against the risk of sleep inertia. The

principal factors influencing the efficiency of ín-flight sleep are the time of day and the

length of the rest period. Other factors influencing sleep efficiency are the duty start

time, the duration of prior wakefulness, and sleep disturbing factors, such as noise,

light, and lack of comfort.

Based on extensive data of aircrew sleeping in bunks, it is estimated that, in the

majority of situa6ons, a pilot resting in a bunk will sleep on average for at least 25% of

the allotted rest period. It is assumed that -if the environment is sufficiently restful- rest

in a first class or top range business class seat ("Lie-Flat" or "Flat Bed" seats) may be as

good as in a bunk. This type of seat is categorized as a Class I seat (see section 5.2.5 for

epeciflcations of all seats). Either a bunk, or Class I seat offers the best opportunity of

obtainíng recuperative sleep in order to maintain adequate levels of alertness throughout

the ftight. It is estimated that sleep in a `normal' business class seat (a Class II seat) is

degraded to 75% of sleep in a bunk or Class I seat, whereas sleep in a flíght-deck or

other seat which reclines by at least 40° to the vertical, with sufflcíent leg and foot

support (a Class III seat) is degraded to 33% of sleep in a bunk/Class I seat. No data are

available concerning on-board sleep in a normal economy class seat (Class IV seat).

Based on laboratory data and ergonomic considerations, sleep in a Class IV seat is

consïdered to be degraded to 0% of bunklClass I seat rest (i.e. it provides no beneflcial

sleep).

Recommendations

Allow an extension to the FDP based on the duration of the rest period available to the

pilot (which could be the sum of two eeparate rest periods) and on the environtnent

which is available for rest. The allowable extension should depend also on whether the

Scan nummer 3 van 3 - Scanpagina 4 van 25

Ingekomen stukken - 1284
TNO report

5125

crew member is `acclimatized', i.e. departing from the home base, having adjusted to

'~local time, or is unacclimatízed to a time zone transition (see section 4 for defmition).

Pb~ the fully acclimatízed indívidual, and based on the bunk/seat elassiFcation given

ábove, allow the following extensíons to the maxirnum permïtted FDP:

Bunk or class I seat: a period of time equivalent to 75% of the duration of the rest

period;

Class Il seat: a period of tíme equivalent to 56% of the rest period;

Class III seat: a period of time equivalent to 25% of the rest period;

Class IV seat: no extension.

For an unacclimatized individual, allow 80% of the acclimatized extension.

To eonform to the recommendatíons of the ultra-long range (1JLR) workshops

organized by the Flight Safety Foundation, the maximum FDP permitted under these

regulations should be limitmd to 18h. If augmentation is only by one additional pilot, the

maximum FDP should be 16h.

T3ased on the above-mentíoned considerations the maximum FDP allowed under

different conditions has been caleulated for cases where the unaugmented FDP is l lh.

The adjustments necessary when the unaugmented FDP is different from 1lh are also

given, thus enabling the maximum permissible FDP to be calculated in all situations.

The recommendations in the present repod are the product of applied scientific

knowledge that is generally accepted by scientists dealing with sleep and alertness

issues in the context of FTL requirements.

Scan nummer 3 van 3 - Scanpagina 5 van 25

Ingekomen stukken - 1284
TNO report

6t25

1 Terms of reference

This report is a delíverable ítem under confract number XXXXX between TNO

Defence, Security, and Safety - Human Factors and the Civil Aviation Authority the

~ëtherlands.

2 Background of the project

After years of political and legislative debate, the new EU-OPS Regulation 189912006

was published on 27 December 2006 (ref 1). On 16 July 2008, these pan-European

minimum standards for Flight Time Limitations ("Subpart Q") will become mandatory

in all EU Member States. National authorities will use 2007 to prepare for changes in

their legíslation to ensure they can meet the deadline and to allow operators and their

crew to adapt to the new rules. l3ased on ETI OFS subpart Q, the Ministry of Transport

of d~e Netherlands made a concept of requírements related to the extensíon of the

maximum flight duty time (NL: vliegdienstperiode), ín case of augmentation of the

cockpit crew and the availability of on-board rest facilities. This concept of

requirements refers to the following articles in EU-OPS Regulafion 1899l2006:

- OPS 1.1095 -1.6: Flight duty period

A flight duty period (FDP) is any 6me during which a person operates in an aircraft

as a member of its crew. The FDP starts when the crew member is required by an

operator to report for a flight or a series of flights; it fmishes at the end of the last

flight on which he/she is an operating crew member.

- OPS 1.1105

1.3: The maximum basic daily FDP is 13 hours.

1.4: These 13 hours will be reduced by 30 minutes for each sector from the third

sector onwards with a maximum total reduction of two hours.

1.5: When the FDP starts in the WOCL~, the maximum stated in point 1.3 and 1.4

will be reduced by 100% of its eneroachment up to a rnaximum of two hours. When

the FDP ends in or fully encompasses the WOCL, the maximum FDP stated in póint

1.3 and 1.4 will be reduced by 50% of its encroachment.

- OPS l.l 115: Extension of flight duty period due to ïn-flight rest

l. Subject to the provisions of Article 8 and providing each operator demonstrates to

the Authority, using operational experience and taking into account other relevant

factors such as current scientific knowledge, that its request produces an equivalent

levei of safety:

1.1 Flight crew augmentafion - the Authority shall set the requirements ín

connection with augmentation of a basíc flight crew for the purpose of extending the

flight duty period beyond the limits in OPS 1.1105 above.

Proposed Dutch CM FTL reguirements: augmentation of cockpàt personned

1. When a standard crew of two pilots is augmented wíth one exfra -fully qualifiedpílot:

a) the operator shall provide a seat that is at least equal to a passenger seat, separated

from the cockpit and-if possible-physically separated from tkte passengers.

b) in that case the max, basic flight duty time can be inereased with 4 hours.

~ The window of oiroadian low (WOCL) is fhe period between 02:00 hours and 05:59 hows. Withtn a band

of fhree Gme zones the WOCL refers to home baso time. Beyond these tlrree time zones the WOCL refers to

home base time for tlre first 48 houxs after departure from home base time zone, and fo tocal time thexeafrer.

Scan nummer 3 van 3 - Scanpagina 6 van 25

Ingekomen stukken - 1284
TNO report

7/25

2. When a standard crew of two pilots is augmented wíth one extra -fully qualifiedpitot:

á) the operator shall provide an onboard sleep faeil'vty, whích is separated from the

eé~clq~it and passengers.

b) in that case Yhe max, basic flight duty Yime can be increased with 6 hours.

3. When a standard crew of two pilots is augmented with two extra -Fully qualifiedpilots:

a) the operator shall provide onboard sleep facilities, which are separated from the

cockpit and passengers.

b) in Chat ease the max. basic flight duty time can be increased with 8 honrs.

2.1 Aim of the project

T NO is asked to give advice concerning extension of the maximum flight duty tíme in

relation to the quality of the available rest facility. In this context, the Authority asks

TNO to answer the following questions:

- with reference Yo point 1 of the proposed requirements:

Study the possibílitíes for differentiation of the flight duty Yime extension Yaking into

consideration seat comfort and the extent of separation of the passengers. Consider the

following seats:

- economy class seat

- busíness class seat

- business class "plus' seat (the "ideal" business class seat)

- with references to poínts 2 and 3:

Study the amount of extension of the flight duty time for augmentation with one and

two pilots respectively in relation to Yhe availability of a sleep facility, which is

separated from passengers and crew.

2.2 Method

Relevant national and intemational liYerature and data will be srirdied and analysed and

recommendations will be made conceming:

- the quality of the different in-flight rest facilitíes in relation to Yhe yield in terms of

sleep, alertness, and performance

- advice, based on carefizl evaluatíon of fhe evidence, on extensions of flight duty time

in relation to the different rest facilities and augmentacion.

The study ís performed in close consultation with Mick Spencer, BA MSe (see

background of the project team).

In this report we descríbe:

- considerations concerning sleep and in-flight sleep

- the relationship of in-flight sleephest with alertness and performance (flight safety)

-considerations concerning the different onboard rest facilities

-probability ofrecuperative sleep/resY in Yhe diflèrent onboard rest facilitíes

- an arifhmetic method to calculate permissíble extensions of fhe maximum basic FDP

Scan nummer 3 van 3 - Scanpagina 7 van 25

Ingekomen stukken - 1284
TNO report

8125

- recommendations conceming extensíon of a maximum basic FDP of 13 hours (as

mentioned in OPS 1.1105-1.3) and of a maximum basic FDP of 11 hours (OPS 1.1105-

I ~ and 1.5) for each type of onboard rest facílity.

-- Tlie report is based on scientific evidence of available data. Areas where scíentific data

were lacking were identífied and expert judgement was used in these cases.

Scan nummer 3 van 3 - Scanpagina 8 van 25

Ingekomen stukken - 1284
TNO report

9/25

3 Requirements of max. FDP extensions of other European CAAs

An Internet search was performed and personal information was requested from several

European CAAs. To date, we have information from the CAAs of the Czech Republic

- aird UK. We are presently not aware of the requirements or proposed requirements

concerning this issue of other European States.

Requirements of the Czech Republic

Auemented Crew (FLT-AC) (art 7.7)

If an augmented crew is used, the maximum permissiblc planned FDP is 16 hours

irrespective of the FDP reporting time, with a rnaximum of 4 landings and provided

the following eonditíons are met:

a) A comfortable reclining seat in the área of cabin arranged for higher than an

economy class (for a multiple class cabín configuration) is available for each resting

crew member

b) A common group of seats (row subsection) may be shared only by another crew

member; under no círcumstances may the common group oI' seats be shared by any

crew member and a passenger

c) Seats intended for crew member(s) rest shall be separated from the flight deck and

screened from the passengers, preferably by a cabin divíder.

Double crew (FLT-DC) (art 7.8)

If a double crew is used, the maximum permissible planned FDP is 18 hours

irrespective of the FDP reporting time, with a maximum of 6 landings and provided

the following conditions are met:

a) For crew members replacing other crew members in flight a sleeping bunk

separated and screened both from the flight deck and from the passenger cabin is

available, and

b) Also comfortable reclining seats which do not necessarily need to be screened

from the passengers are available.

Requirements of the L7nited Kingdom

Extension of Fl~mg AutPeriod by-In-tlieht Relief

l. When any additional crew membex is carned to provide in-flight relief with the intent

of extending an FDP, that individual shall hold qualificatíons whích are equal or

superíor to those held by the crew member who is to be rested. To take advantage of

this facility the division of duty and rest between crew members must be kept in

balanee. It is unnecessary for the relieving crew member to rest in between the Címes

relief is provided for other crew members.

2. When ín-flight relief is utilised there must be, for the crew members resting, a

comfortable reclining seat, or bunk, separated and screened from the flight deck and

passengers.

3. A total in-flight rest of less than three hours does not allow for the extension of an

FDP, but where the total in-ffight rest, which need not be consecutive, is three hours or

more, then the permitted FDP may be extended as follows:

If rest is taken in a bunk: A period equal to one half of the total rest taken, províded that

the maximum FDP permissible shall be 18 hours; 19 hours in the case of cabin crew.

Scan nummer 3 van 3 - Scanpagina 9 van 25

Ingekomen stukken - 1284
TNO report

10125

If rest is taken in a seat: A period equal to one third of the total rest taken, provided that

`the maximum FDP permissible shall be 15 hours; 16 hours in ihe case of cabin crew.

Scan nummer 3 van 3 - Scanpagina 10 van 25

Ingekomen stukken - 1284
. TNO report 19 / 25

4 Background on sleep and alertness

T'"ci maintain round the clock operations, mernbers of an airerew often have to sleep

~4hen eheír circadian clock dictates wakefulness and to fly when theír clock díctates

slëép. Short haul aircrew are often faced with irregular work schedules, early moming

depariures, and late arrivals, resulting in ímpaired sleep and in-flight sleepiness (Simons

& Valk, 1998; Gander & Graeber, 1987). Long haul operations are characterized by

rapidly alternating time-zone transitions and night flyíng (e.g. Graeber et al. 1986;

Petrilli et al. 2006). Layovers are often too long to keep sleep and activity patterns

anchored to home time and too short for complete circadian adaptation to the local

environment. The unique combination of shífted time and shifted work results in

compound cireadian disruptions. Consequenees, such as impaired sleep, lowered

alertness, and Patigue may affect flight safety and health (e.g. Samel et al. 1993; Petrie

et al. 2004; Eriksen & Akerstedt, 2006; Jackson & Earl, 2006). Sleep reduction may

lead to lowered alertness and ímpaíred performance (Carskadon & Dement, 1981;

Horne & Willzínson, 1985; Valk et aL 2003), while flying requires optimal cognition

and alertness (Valk et al. 1997).

Sleep is a vital physiological body funetíon and sufficient sleep is a major

countermeasure against fatigue, lowered alertness, and in-flight sleepiness. It is

therefore important for flight crew to use the scheduled rest periods to obtain the best

possible sleep.

Sleep is composed of two distinct states: non-rapid eye movement, or NREM, and rapid

eye movement, or REM, sleep. During NREM sleep, physíological and mental activities

slow (e.g., heart rate and breathing rate slow and become regular). NREM sleep is

divided into four stages, with the deepest sleep occurring during stages 3 and 4. Deep

sleep, also called slow-wave sleep (SWS), has important recuperative properties and

growth-inducing propertíes involved ín maintaining general health. If awakened during

this deep sleep, an índividual may take some time to wake up and then continue to feel

groggy, sleepy, and perhaps disoriented for 10 to 15 minutes. This phenomenon is

called sleep inertia.

REM sleep is associated with an extremely active brain that is dreaming, and with

bursts of rapid eye movements; during REM sleep, the major motor muscles of the body

are immobile. If awakened during REM sleep, individuals can often provide detailed

reports of their dreams. REM sleep is important for mental recuperation and mental

capacities, sueh as memory, leaming, cognitive performance and mental health.

Over the course of a typical night, NREM and REM sleep occur in cycles. Stage 1 or

drowsy sleep usnally oceurs during the transítion from waking to sleep. Stage 2

sleep normally occupies 50% of the sleep period. The time taken to reach the first

episode of stage 2 is termed "sleep onset latency". Deep sleep (stages 3 and 4), also

called slow wave sleep (SWS), predominates in fhe early part of the sleep period

and is influenced by the daration of prior wakefulness. Episodes of rapid eye

movement slecp (REM) occur at interoals and are associated with dreaming. The

normal sequence of sleep stages during the night is: waking, stage 1, stage 2, stage

3, stage 4, stage 3, stage 2, REM sleep, followed by the next cycle starting with

stage 2, etc. Each sleep cycle lasts around 90-100 minutes. As the night proceeds,

the content of the sleep cycles alters, wíth less slow wave sleep and more RDM

sleep in later cycles. The last part of a normal night's sleep generally consists

mainly of sleep stages 1 and 2.

Scan nummer 3 van 3 - Scanpagina 11 van 25

Ingekomen stukken - 1284
TNO report

12125

l~ecuperative sleep

Lt" can be concluded that for optimal recuperation of physical and psychological

~unctions both NREM and REM sleep are important. To be recuperative, the duration of

yecp should be sufficíently long to allow for NREM and REM. Sleep duration is the

principal deternvnant of the recuperative value of sleep (Dinges et al., 1997; Wilkinson

et al., 1966).

The literature provides sufficient evídence that duration and quality of pre-trip sleep are

important determinants of pilot performance and alertness (e.g. Carskadon & Dement,

1981; Carskadon & Dement, 1982; Rosekind, Graeber, Dinges, Connell, Rountree &

Gillen, 1992; Pascoe et al. 1994; Valk & Simons, 1998). In aircrew, quality and

duration of pre-flight sleep may be impaired by operational demands and círcadian

disruptions. Several studies of the sleep of airerew during layovers after time zone

transitions found impaired sleep. In particular, the second and third night during

layovers showed poorer sleep quality (e.g. Simons et al. 1994). ln circadian terms,

aircrew with circadian dismption and poor sleep quality during layovers are considered

as unacclimatízed (i.e. Co have some degree of `jet lag'). UnaccHmatized aircrew may

experienee more alermess problems on a (return) flight than aircrew that have theír

body clock acclimatized to the local environment.

For regulatory purposes, `acclimatized' ean be defined as follows: "When a crew

member has spent 4 consecutive local nights on the ground within a time zone which is

2 hours wide, centred on the home base, and is able to take uninterrupted nights sleep.

The crew member will remain acclimatised thereafter until a duty períod fmishes at a

place where local tirne differs by more than 2 hours from that at point of departure." As

mentioned, this defmítion is used for regulatory purposes. From a scientific point of

view this definition does not guarantee full physiological acclimatization, as some

individuals may need a longer period of time to acclímatize completely. Moreover,

acclimatization generally takes more time after eastward than after westward tíme zone

transitions.

Impaired pre-flight sleep and circadian disruption may result in lowered alertaess and

perfomiance levels during the flight, ln-flight alertness and performance levels may

further be lowered by long work periods, night flying, and monotony during cruise

flight. Analysis of the data of 156 cockpit crew flying eastward, westward, and

southward intercontinental trips showed that after more than 8 hours continuous flight

duty, alertness and vígilance levels are significantly impaíred compared to tûose found

earlier during the flight (Roelen et al. 2002). Table l, based on an aleriness model

derived from a large database of experimental data, clearly shows that alertness

decreases as FDPs become longer (Speneer et al. 1998). Therefore, augmentation of the

crew and implementation of in-flight sleep periods may be necessary to maintain

sufficient alertness and performance levels during a long-haul flight. Moreover, table I

shows that in-flight alertness levels are also híghly influenced by the time of day that an

FDP starts. This ís particularly important for scheduling of rest periods on ultra-long

range flights.

Scan nummer 3 van 3 - Scanpagina 12 van 25

Ingekomen stukken - 1284
TNO report

13/25

Table 1. Alertness scores (VAS scale) and equivalent blood-alcohol levels (BAC promille ~oo) related to

FDP hours.and start of FDP. Highest alertness scores 100. When the FDP starts at 10:00 alertness is

' `împäîred t© ä BAC level of 0.42yoo after 15.2 hrs. When the FDP starts at 18:00 this level is reached

'after 10.3 hFs (Spencer et ai. 1998 . __

alertness score

80 70 60 50 40 30 20

hours before level reached

during FDP starting at 10:00 6.1 8.4 10.7 12.9 15.2 17.5 19.7

hours before level reached 12 3.5 5.7 8 10.3 12.6 14.9

during FDP starting at 18:00

equivalent level BAC (°ko) 0.00 0.03 0.14 0.27 0.42 0.62 0.85

In Jdàght sleep

In-flight sleep is consídered as recuperative or restorative, when it enables aircrew to

maintain sufficient performance and alertness levels throughout the entire flight. Many

studies bave demonstrated the benefits of short periods of sleep on subsequent

performance and alertness during a prolonged period of work (e.g. Nicholson et al.

1985; Dinges et al. 1987; Sirnons et a. 1994, Rosekind et al. 1994; Robertson & Stone,

2002 etc), and there is evidence to suggest that this is more effective than a nap taken

when ímpaired performance is akeady established and the time available for sleep is

very short (Rogers et al. 1989; Dinges et al. 1988; Naitoh et al. 1982). The longer the

length of prior wakefulness, the greater the amount of sleep needed for the recovery of

performance (Rosa et aL 1983; Wilkinson, 1972).

There is extensive evídence that performance is better maintained after sleep periods of

longer duration (Naitoh et al. 1982, Spencer, 2002; Robertson & Stone, 2002; Sígnal et

al. 2003). In a survey comprising aircrew on 851 intercontínental 747-400 flights, it was

found that alertness, measured on a Visual Analogue Scale, inereased with 5% for each

hour of sleep (Spencer, 2002). Although longer sleep periods are more beneficíal than

very short periods (<lh), longer sleep increases the probability of sleep inerfia after

awakening. Therefore, after a sleep of more than 1 hour a piloC should take at least 15-

20 min to overcome sleep inerCia before he/she refieves a colleague in the cockpit

(Simons et al. 1994; Robertson 8c Stone, 2002). Very shorC sleep periods (45 min in a

cockpit seat) have been shown to enhance performance and alertness briefly in those

pilots who slept for that time (Rosekind et al. 1994; Simons & Vallc, 1997). However,

these short cockpit naps are generally considered as an emergency measure to prevent

pilots from falling asleep and they should not be considered in FTL planning, because

they do not guarantee that a suFficient level of alertness will be maintained tbroughout

the flight until landing.

Several studies demonstrated the benefits of in-flight sleep in terms of improved

alertness, although they also indicated that the a6ílity to obtain adequate sleep is

influenced by the sleep environment, by the timing of the flight in relation to the

eircadian sleep-wake cycle, and by the duration of wakefulness prior to the allocated

Scan nummer 3 van 3 - Scanpagina 13 van 25

Ingekomen stukken - 1284
TNO report

14125

rest period (Pascoe et al. 1994; Simons et al. 1994; Rosekind et al. 1994; Pascoe et al.

')995; Spencer, 2002; Signal et al. 2003). Onboard sleep wíll be most efficient, when the

ííY flight rest ís taken duríng the normal sleep period of Yhe body clock; e.g. during the

pight (e.g. Símons et al., 1994; Valk & Simons, 1998; Pascoe et al. 1994). When the

rés"t period coincides with the circadian activity phase, one needs to take into account

that at least some pilots will not be able to sieep at all, or will have a very low sleep

efficiency.

In summarv ít is concluded that:

- Short in-flight sleep periods are an effectíve measure to maintain aleriness and

perlórmance at sufficient levels throughout a long-haul flight.

- Alertness and perfonnance are better maintained after sleep periods of longer duratíon.

- The benefit of sleep periods of longer duratíon has to be balanced against the risk of

sleep inertia.

- The principal factors influencing the efficiency of in-flight sleep (the proportion of the

rest period occupied by sleep) are the time of' day and the length of the rest period.

Other factors influencing sleep efficiency are the duty start time and the duration of

prior wakefulness.

Causes of sleep disturbance

The quality of sleep can be as critical to well-being as the quantity of sleep. If an

individual obtains 8 hours of sleep but the sleep is disturbed, then upon awakening, the

indivídual may feel as if less sleep was obtained. There are many díverse reasons for

disturbed sleep, from anvironmental factors (e.g. noise, lighY) to physieal sleep

disorders. Noise, light, temperature, and a variety of other factors may decrease the

quantity and quality of sleep, in particular, when sleep ís taken at a time when the body

is not "ready" for sleep (during the circadian activíty phase) or in an environment that is

not conducive for sleep (lack of privacy, seat reclínes less than 40°). Of those factors,

noise and líght are the most cited and established sleep disturbing factors (see e.g.

Miedema & Vos, 2007 for noise and Campbell et al. 1995 for light).

5 Crew rest facilities

Onboard crew rest facilities include sleep bunks, first classltop range business class

seats, normal business class seats, flight deck seats or other seats which recline at least

40°, and a normal economy class seaY. In this section, we review Yhe above-mentioned

rest facilities in relation wíth the probability of obtaining recuperatíve sleep.

5.1 Sleep in a sleep bunk

A sleep bunk is an onboard rest facílity that is compleYely separated from the cockpit

and the passenger compartment. In most cases, it has two beds (double-decker)

allowing for horizontal rest. The facility can be eompletely darkened. The ideal sleep

bunk also has a comfortable seat, climaYe and humidity control systems, and is

adequately insulated and situated to minimize random and aircraft noise. An example of

the requírements of an adequate sleep bunk is provided by the Australian and

lntemational Pilots Association facility standard AIPA-RS 001-1998 (Flight Safety

Foundation, 2003).

Scan nummer 3 van 3 - Scanpagina 14 van 25

Ingekomen stukken - 1284
TNO report

15/25

There have been many surveys of the quality of the sleep bunks (e.g. De Ree et al.

1993; Pascoe et al. 1994; Rosekind et al. 1994). Results of these surveys showed high

cönformity concerning the factors that can improve or degrade the quality of sleep

öbtained in the bunk. Issues ínclude:

- - sndden noises, e.g. slamming of doors, passenger announcements, toílets flushing,

galley noises (positioning of bunks very ímportant)

- background noise from aircraft;

- turbulence (positioning of bunk important: front/back of aircratï, transversel

Longitudinal);

- temperature (too hot , too low);

- humidity (humidifiers, íf fitted, can be unreliable);

- bedding: thís is often inadequate;

- privacy. other bunk occupant, if applicable

- thoughts on mind (responsibility for the ftight operation, personal problems).

Studies of sleep characterístics have been carried out ín bunks of different types of

aireraft (B747-400, MD 11, B 777 and 777-200ER, Airbus 340-500). Full objective

(EEG: electro-encephalography) and subjective monitoring demonstrated that, in most

cases, the quality of sleep that aircrew achieved was relatively good: at times when they

were particularly tíred, they managed to get lengthy periods of SWS. At other times

sleep was disturbed, but that was often because they were attempting to sleep at an

unusual 6me relative to ttreir body clock. This established that there was no major

problem with sleeping on aircrafr, given the appropriate facilities (e.g. Spençer et al.

1990; Pascoe et al. 1995; Simons et al. 1994; Rosekind et al. 2000; Signal et al. 2003;

Spencer & Robertson, 2004).

These studies have shown that sleep periods of six hours and even longer are possible.

This is important particularly with the new generation of ultra-long-range (ULR)

aireraft capable of contínuous flights in excess of 18 hours (Signal et al. 2003).

Models to predict the amount of sleep achieved have been developed from the large

amount of data (mainly subjective and actigraphic) that have been collected (Spencer,

2002). These models have demonstrated

the influence of various factors on the 5 ...,.,...,~,..shrestper~°d-----------------------

amount of sleep obtained, the most ~", -sr, rest per~od

important of these factors being the a - -----ai, re°t peràa- . - - - .. - - . - . - - - -

duration of the rest period (i.e. the time · -°°-3hrestperbd

G -~----2h rest perrod

available for sleep) and the time of day .°- 3 -

-ih rest perrod "r"

at which sleep is attempted (see the ~ ' ~ ~' »~

adjacent figure). It has also been shown á z - ----- ~~.·'''~- ~° ·~-

that bunk sleep is associated with an _d ~, J·~°p~°"~

inçrease in alertness (Spencer, 2002; " t - .

Spencer & Robertson, 2000). honger

periods of sleep tend to be associated o

~a ~s ~a zo zz o z a s

with higher subsequeni levels of

alertness (Spencer et al 2004). However, time of day (h)

the increase has been shown to be less strong (approximately 80% effective) on a return

flight than on an outward flíght (Spencer 2002), suggesting that the recuperative value

of the sleep obtained may be less pronounced during a period of circadian disruption.

This model has been validated on a further set of data, where it was confirmed that the

average amount sleep obtained was close to the predicted values (Robertson et al 2002).

Scan nummer 3 van 3 - Scanpagina 15 van 25

Ingekomen stukken - 1284
TNO report

16125

5.1.1 Sleep in a crew bunk: implications for FTL

"~iïe figure suggests that, except at the least favourable times (which are normally when

people are not very tired), it is normally possible to sleep for around 33% of the allotted

- röst period. Allowing for less restful sleep than the ideal (as discussed above), and to err

on the conservative síde, a reasonable working figure would be 25%. On the basis of lh

sleep for 2h wake, this would suggest that the sleep obtained could allow an addition to

the FDP of 25x3=75% of the length of the rest period. This builds in a conservative

element, as short sleeps tend to contain more deep (slow-wave) sleep. However, this

would need to be reduced, say to 50%, for the return fiight. Thís would assume bunks of

a reasonable standard (see the discussion above).

The question arises whether this approach is still valid for duty periods whích are

considerably longer than those from which this information has been drawn. The

requirement to regulate for very long FDPs has become a pressing issue with the arrival

into service of a new generation of aireraft able to fly continuously, with a full

complement of passengers, for 16h or more. To address thís question, the Flight Safety

Foundation organized a series of intemational workshops between 2001 and 2005,

bringing together representatives from the aircraft industry as well as regulators and

scíentific and meäical experts. A consensus was reached that, untíl these new operations

have become firmly established, each new schedule would require separate evaluatíon,

based on the concept of the `city-pair' (Flight Safety Foundation, 2003).

To conform with the recommendatíons from these workshops, it would be necessary to

limit the extensions proposed here so that the maacimum FDP does not exceed 18h, even

where a double crew is provided. Beyond thís limit, the city-pair approach should be

adopted. To ensure consistency with the 18h limit for 4-crew operations, it is

recommended that a límit of 16h be imposed for a 3-crew operation (Flight Safety

Foundation, 2003).

5.2 Sleep on the aircraft elsewhere than in a bunk

5.2.1 First Class seat or top range business class seat

A first class or top range business class seat may offer a qualíty of sleep that is

compamble to sleep in a bunk faciHty, beeause the seat offers horizontal rest, which is

similar to a bed. However, sleep can only be as good as in a bunk under the condition

that this seat is completely separable from the passengers (privacy is important) and

offers a completely darkened environment. The seat has to be sereened by curtains or

panels. Ünder these conditions, we consider the probability of obtaining recuperative

sleep to be equal to the sleep bank.

5.2.2 Normat Basiness class seat

A normal business class seat cannot be completely reclined to offer a borizontal

sleeping position for the whole body (including legs). There is often less space around

the sleeping position than around a first class/top range business seat, which makes

adequate separation from the passengers and random noise more difficult. Based on

these ergonomic considerations, it is surmised that it will be more dífiicuh getting to

Scan nummer 3 van 3 - Scanpagina 16 van 25

Ingekomen stukken - 1284
TNO report

17/25

sleep and remaining asleep. Of course, resting crew members can use eyeshades and

qarplugs, which helps to some extent. However, this might interfere with getting to

slëep ín individuals who experience these aids as irritating.

£~a`ta of in-flight sleep characteristics are scarce. QinetiQ has studied sieep and alertness

of flight crew using business class seats as crew rest on the Dubai-Perth route

(Bmirates Airline), where bunk facilities were not provided on the B777 aireraft

(Spencer et al. 2004). On average, sleep in the seat was reduced by approximately 25%

compared with sleep during similar rest periods in a bunk on the B747. Crews reported

greater difficulty in getting to sleep and remaining asleep than in the bunk studies. They

aiso made more frequent use of earplugs and eyeshades. Nevertheless, tle amount of

sleep that they did get was as effecfive in improving alermess as a similar amount of

bunk sleep. This suggests that any relative impairment associated with sleeping in a seat

was due to the duration rather than the quality of the sleep obtained.

5.2.3 Flight deck or other seat that reclines at least 40°

Lying down is the preferred position to sleep for adult human beings. Sleeping ín a seat

with back angles to the vertical of less than 90° has been studied by Nicholson and

Stone (Nícholson & Stone, 1987). Nocturnal sleep was assessed electroencephalographically in men between 29 and 48 years of age, sleeping in a bed and in three seats

with back angles to the vertical of 49.5° ("sleeperette"), 37.0° (reclining seat), and 17.5°

(armchair). It was found tá~at sleep in fhe sleeperette did not differ from that in bed, but

in the reclining seat the duration of sleep was reduced and the amount of awake acGvity

was increased. Sleep in the armchair was markedly worse than in any of the other three

conditions. The investígators concluded that adequate sleep may be obtained in seats as

long as Yhe baek angle with the vertical approaches 40°.

It is anecdotally known that pilots often prefer to try and sleep in the seaf at the back of

the flight deck instead of an economy class seat. Although the loca6on of the seat offers

no separatíon from the cockpit, most types of seats at the back of the flight deck can

(fully) recline and offer separation from the passengers. For a seat at the back of the

flight deck, there is evidence from one of the Haj studies that were performed by

QinetiQ (Spencer & Robertson 1999). The schedules ínvolved flights of between 1 Oh

and 12h at all times of day across three or four tirne zones ín both directions. In this

study, the pilots used the jump seat ín the 13767, whieh rotated into a position where ít

would fully recline. They had to improvise a foot/leg-rest. The sleep they obtained was

between 40% and 50% of that achieved in the B767 bunk (whích was of a lower

specification that the 8747 bunks used in most of the above studies). Sleep was also of

poorer subjectíve quality.

5.2.4 Economy class seat

Although there have been no studies of sleep and alerCnsss of airerew seated in an

economy class seat, it can be assumed that the próbabílity of obtaining recuperative

sleep in such seat will be minimal. This assumption is based on the following arguments

used:

Scan nummer 3 van 3 - Scanpagina 17 van 25

Ingekomen stukken - 1284
TNO report 18 / 25

- the seat does not recline more than 40° back angle to the vertical and has no

ópportunities for adequate foot and leg rest, which diminishes the probability of

rëcuperative sleep (Nicholson & Stone, 1987).

- space around the seat is not sufftcient to create an adequate separatíon from the

passengers (jostle ín economy class), or guarantee any privacy.

- a majority of passengers are unable to sleep at all in an economy seat. With the help of

sleeping aids or alcohol, some passengers succeed in obtaining some sleep, but they

often feel a general malaise after sleeping in a cramped position.

5.2.5 Sleep on the aircraft elsewhere than in a bunk- implications for FTL

i. A fully-reclining first-elass seat or top óf the range business class seat, separated

from other passengers. If the environment is sufficiently restful, then this should be as

good as a bunk (see sectíon 5.1 for requirements of a crew bunk). In the context of the

present report this seat is classified as Class I seat.

Requirements of a Class I seat:

The seat should provide horizontal rest as in a bed. It should be recüning to at least

80° back angle to the vertical. Examples are so-called "Lie-Flat" seats, or "Flat Bed"

seats. The seat should be separated from the cockpit and passengers (by curtains or

panels) and provisions for darkening of the sleep envíronment should be available.

ü. A `normal' business class seat. The above would suggest a degradation to 75% of

bunk rest. This seat is classified as Class ü seat.

Requirements of a Class II seat:

A seat outsíde the cockpit and separated from the passengers by -at least- a dark

curtain. A common group of seats (row subsection) may be shared only by another

crew member; under no circumstanees may the common group of seats be shared by

any crew member and a passenger. Mínímal requirements of the seat are:

(a) reefiníng to at least 45° baek angle to the vertical;

(b) seat pitch2 at least 55 inches (137.5 em);

(c) seat width at least 20 inches (50 cm);

(d) suPficient leg and foot support.

üi. A ftight-deck or other seat which reclines by at least 40° back angle to the vertical

and offers sufficient leg and foot rest. The above would suggest a degradation to 33% of

bunk rest. This seat ís classified as Class 1II seat.

Requirements of a Class III seat:

A seat in the cockpit or in fhe passenger cabin reclining to at least 40° frorn the

vertical and providing sufftcient leg and foot support.

iv A normal economy class seat. Until a study is carried out on this, we recommend no

extension of FDP. This seat is classified as Class IV seat.

' Seat pitc6 ís fhe distance between Yhe rows oP seats and is measured from the back of one seat to the baok

of the seaf behind, tbe measurements being takon from the same posítion on eaoh seat.

Scan nummer 3 van 3 - Scanpagina 18 van 25

Ingekomen stukken - 1284
TNO report

19/25

6 Summary of recommendations

ÄI'low an extension to the FDP based on the duration of the rest period available to the

pilot (which could be the sum of two separate rest periods) and on the environment

í~ïliich is available for rest. The allowable extensíon should depend also on whether the

crew member is `acclimatized', í.e. departing from the home base, having adjusted to

loeal time, or ís unacclimatized. A more precise defmition of acclimatízation ís given in

section 4 and below under `Implications for FTL'. This is provided as a working

definition 'for the purpose of the regulations, and does not guarantee full physiological

acclimatization.

For the fully acclimatized individual, and based on the bunk/seat classification given

above, allow the following extensions to the maximum permitted FT)P:

Bunk or elass I seat: a períod of time equivalent to 75% of the duration of the rest

period,

Class IT seat: a period of time equivalent to 56% of the rest period,

Class III seat: a period of time equivalent to 25% of the rest period.

Class IV seat: no extension.

For an unacclimatized individual, allow 80% of the acclimatized extension.

The maximum FDP permitted under these regula6ons should be limíted to 18h. If

augrnentation is only by one additional pilot, the maximum FDP should be 16h (see

section 5.1.1).

Example

The following assumes that the time available for rest is 3h less than the FDP time. This

allows for pre-TOC and post-TOD and possibly some fime lost in handover. It also

assumes an equal divisíon of rest between the crews.

Consider a retum fiight with three pilots and with bunk facilities, where the maximum

unaugmented flight time is 13h. The permitted extension would be 2h 30min.

The working is as follows:

cruíse phase = 15.5 - 3 = 12.5

rest periods =12.5 / 3 = 4.17

reduce by 0.75 x 0.80 for the retum flight = 0.6

4.17 x 0.6 = 2.5

so the max FDP would be 13 + 2.5 = lS.Sh

If a value greater than 15.5 is used in the above calculation, then the maximum

allowable FDP is relatively smaller. For example, using a starting value of 16.5h:

cruise phase = 16.5 -- 3 = 13.5

rest periods = 13.5 /3 - 4.5

reduce by 0.75 x 0.80 for the retum flight = 0.6

4.5 x 0.6 = 2.7

so the maximum FDP would be 13 + 2.7 = 15.7h.

Therefore a value of 16.5 cannot be achieved.

Scan nummer 3 van 3 - Scanpagina 19 van 25

Ingekomen stukken - 1284
TNO report

6.1 Imptications for FTL

20 / 25

Ttïe maximum FDP allowed under dífferent conditions can be calculated in a similar

t~anner to the above, and these calculations can be made the basis for the FTL rules.

Tlié fullowing table, applicable to a duty in which the maximum unaugmented FDP is

11h, is based on this approach. As indicated in the Cable, the limits that are applicable in

the general case can be extended if the crew member is acclimatízed prior to departure.

Table 2: max. perntissible extended FDP in case unangmented FDP = 1 lh

(extended FDPs in hrs:minj

Wtere the unaugmented FDP is greater than 1 lh, the additional allowable duty time can

be calculated from Table 3. This table shows the additional time that is allowed îor each

hour by which the unaugmented FDP exceeds 11 h.

Table 3: additíonal tíme (hrs:min) per hour for unauemented FDPs different from 1 Ih

For example, if the unaugmented FDP is 13h, the maximum for an acclimatized threecrew operation in a class II seat is 12:45 + 2 x I :15 = 15:15. If the unaugmented FDP is

less than I lh, the new value is obtained similarly by subtraction.

As díscussed in section 5.1.1, the maximum for augmented crews should be limited to

18h (double crew) and 16h (3-crew).

Taking above-mentioned limíts into consideration and using tables 2 and 3, calculations

ean be made that provide the science-based answers to the questions of the Dutch

Authority conceming the extent of pemtissible extension of the maxímum basic FDP.

A crew member may be considered, for the purpose of these recommendations, to be

acclimatized when he/she has spent four consecutive local nights on the ground within a

time zone which is two hours wide, centred on the home base.

Scan nummer 3 van 3 - Scanpagina 20 van 25

Ingekomen stukken - 1284
.= TNO report

21/25

Recommended maximal nermissible extensions for a basic maximnm FDP of 13 h

~Víth a basic maximum FDP of 13 hours, the recommended maximal permissible

extensions are:

f. augmentatíon with onepilot and availability of a rest facilíty that is a:

-~leep bunk or Class I seat: 2:30 6rs for unacclimatízed crew and 3:00 hrs (= 3:25 cut

oü at the 7 6 h limit) for acclimatized crew.

- Class II seat: 1:50 hrs for unacclimatized crew and 2;15 hrs for acclimatized crew.

- Class III seat: 0:40 hrs for unacclimatízed crew and 0:55 hrs for acclimatized crew.

-Class IV seat: no extension.

2, augmentation with rivo oilots and availability of a rest'facility that is a:

- Sleep funk or Class I séat: 4:20 6rs for unaeclimatízed crew and 5:00 hrs (= 5:55 cut

off at the 18 h limit) for acclimatized crew.

- Class II seat: 2:45 hrs for unacclimatized crew and 3:50 hrs for acclimatized crew.

- Class III seat: 1:10 hrs for unacclimat'ized crew and 1:35 hrs for acclimatized crew.

- Class N seat: no extension.

Recommendations concerning the maximal permissible extensions of a maximum basic

FDP of I I hours are presented in table 2.

Recommendatáon concerning Class IV seat (F.,conomy class)

Scientific data concerning in-flight sleep in an economy class seat are lacking. Based on

ergonomic principles and lack of adequate separation of such seat from the passengers,

we assume the probability of obtaining recuperative sleep in a normal economy class

seat to be minimal Therefore, we recommend to permit no extension of the basic FDP

for an economy class seat until a study is carried out on sleep and alertness of pilots

resting on a Class IV seat. In case the use of an economy seat for relief crew is further

considered by the Authority, such study is recommended.

7 Comparison with requirements from other European countries

The recommendatíons in the present report are the product of applied scientific

knowledge that is generally accepted by scíentists dealing wíth sleep and alertness

issues in the context of FTL requirements. It is not known whether scientific Irnowledge

has been used to construct the requirements ef the Czechoslovakian and UK

requirements (see section 3), or that these were made using operational experience and

knowledge, which are also ímportant considerations.

When comparing the recommendations of the present report wíth the Czechoslovakian

and IJK requírements, it can be seen that:

- the present recommendations are more dctailed (also consider max.FDPs shorter than

13 hrs) and allow for calculation of the additional allowable duty time for every hour

the FDP may wished to be extended.

- the present recommendations compare well with the IJK requirements, but are

somewhat less restrictive conceming the extent of extension when a seat is used by the

relief crew;

- the present recomtnendatíons compare well with the Czechoslovakian requirements,

but are somewhat more restrictive where unacclimatized crew are considered and where

a seat is used by the relief crew.

Scan nummer 3 van 3 - Scanpagina 21 van 25

Ingekomen stukken - 1284
TNO report

zz / as

8 References

Cámpbell, S.S., Dijk, D.J., Boulos, Z., Eastman, C.L, Lewy, A.J., Terman, M. (1995).

Light treatment for sleep disorders: consensus report. III. Alerting and activating

> -- · a~iects. Journal of Biological Rhythms 1995 10(2):I29-132.

Carskadon, M.A. & Dement, W.C. (1981). Cumulative effects of sleep restrictíon on

daytime sleepiness. Psychophysiology, 18, 107-113.

Carskadon, M.A. & Dement, W.C. (1982). Noctumal determinants of daytime

sleepíness. Sleep, 5, S73-SBI.

De Ree JJD, Simons M, Valk PJL, Veldhuijzen van Zanten OBA. (1993). Onboard

Crew Rest Facifities. In: Proceedings of the Seventh International Symposium on

Aviation Psychology. Jensen RS, Neumeister D. (Eds). The Ohio State University,

Columbus OH, 1993. p. 639-44.

Dinges DF, Whitehouse WG, Ome EC, Orne MT. (1987). Temporal placement of a nap

for alertness: Contributions of circadian phase and prior wakefulness. Sleep. 1987;

10:313-329.

Dinges, D.F., Whitehouse, W.G., Orne, E.C., Orne, M.T. (1988). The benefits of a nap

during prolonged work and wakefulness. Work and Stress, 2, 139-152.

Dinges DF, Pack F, Williams K, Gillen KA, Powell JW, Ott GE, Aptowicz C, Pack AI.

(1997). Cumulative sleepiness, mood disturbance, and psychomotor vigilance

performance decrements during a week of sleep restricted to 4-5 hours per night. Sleep.

1997 Apr;20(4):267-7.

Eriksen CA, Akerstedt T. 2006. Aírcrew fatigue in trans-Atlantic moming and evening

flights. Chronobiology International 23(4): 843-858.

European Union. (2006). Official Journal of the European Union, 27 December, 2006.

Subpart Q: Flight and Duty Time Limitatíons and Rest Requirements pp. L377/161-

167.

Flight Safety Foundation. (2003). Consensus emerges from internatíonal focus on crew

alertness in ultra-long-range operations. Flight Safety Digest, May-June 2003. p.l-21.

Gander, P.H., Graeber, R.C. (1987). Sleep in pilots flying short-haul commercial

schedules. Ergonomics, 30(9), 1365-1377.

Graeber, R.C. (1986). Sleep and wakefulness in ínternational aírerews. Aviation Space

and Environmental Medicine, 57, B 1-B64.

Jackson CA, Earl L. 2006. Prevalence of fatigue among commercíal pilots.

Occupational Medicine (Lond) 56(4): 263-268.

Miedema, H.M., Vos, H. (2007). Associations between self reported sleep dísturbance

and environmental noise based on reanalyses of pooled data from 24 studies. Behavioral

Sleep Medicine 2007, 5(1):1-20.

Scan nummer 3 van 3 - Scanpagina 22 van 25

Ingekomen stukken - 1284
TNO report

23 I 25

~aitoh P, Englund C, Ryman D. (1982). Restorative power of naps in designing

cöntínuous work schedules. Report no:82-25. San Diego (CA): Naval Health Research

~enter; 1982.

Nicholson AN, Pascoe PA, Roehrs T, Roth T, Spencer MB, Stone BM, Zorick F.

(1985). Sustained performance with sustaíned evening and morning sleeps. Aviation

Spaee Environmental Medicine. 1985; 56:105-114.

Nicholson AN, Stons BM. (1987). Influence of back angle on the quality of sleep in

seats. Ergonomics 30(7): 1033-1041, 1987.

Pascoe PA, Jolmson MK, Montgomery JM, Robertson KA, Spencer MB. (1994). Sleep

in rest facilitíes onboard aircraft: Questíonnaire studíes. IAM Report no ?78, August

1994.

Pascoe PA, Johnson MK, Robertson KA, Spencer MB. (1995). Sleep ín rest facílities on

board aireraft: Field studies. DRA Report No DRA/CHS/A&N/CR/95/002, March

1995.

Robereson KA, Stone BM, Gillibrand SB. (2000). Implications of disturbed daytime

sleep &>r aircrew. CAA Paper 2000/7, Oct 2000.

Robertson KA, Stone BM. (2002). The effectiveness of short naps in maintainíng

alertness on the flightdeck: a laboratory study. QINET`IQ/CHS/P&D/ CR020023/1.0,

Feb 2002.

Robertson KA et al. (2002). Predicting alertness in fizture ultra long-range operations: a

validation study by ECASS, QinetiQ Report No QINETIQ/KI/CHS/CR021119/2.0,

September 2002.

Roelen ALC, Wever R, Hale AR, Goossens LHJ, Cooke RM, Lopuhaä, Simons M,

Valk PJL. (2002). Causal modeling of air safety - Demonstration model. Report NLRCR-2002-662. National Aerospace Laboratory NLR, Amsterdam, The Netherlands,

2002.

Rogers AS, Spencer MB, Stone BM, Nicholson AN. (1989). The influence of a 1 h nap

on performance ovemight. Ergonomics. 1989; 32:1193-1205.

Rosekind, M.R., Graeber, R.C., Dinges, D.F., Conell, L.J., Rountree, M.S., Spinweber,

C.L. & Gíllen, K.A. (1992). Crew Factors in Flight Operatíons: IX. Effects of

preplanned cockpit rest on crew performance and alertness in long-haul operations.

NASA Technical Memorandum 103884. NASA-Ames Research Center, Moffett Fíeld,

CA.

Rosekind, M.R., Gander, P.H., Conncll, L.J., Co, E.L. (1994). Crew factors in ílight

operations X: alertness management in flight operatíons. NASA Technical

Memorandum, DOT/FAA/RD-93118. NASA Ames Research Center, Moffett Field,

CA.

Scan nummer 3 van 3 - Scanpagina 23 van 25

Ingekomen stukken - 1284
TNO report

24 / 25

Rosekind MR, Gregory KB, Co EL, Miller DL, Dinges DF. (2000). Crew factors in

'~Iight operations XTI: a survey of sleep quantity and quality in on-board erew rest

fäcílities. NASA Report no. NASA/TM-2000-209611. NASA Ames Research Center,

lGloffett Field, CA. September 2000.

Samel, A., Wegmann, H.M. (1993). Extended range operations - a review of recent

developments. AGARD CP-547. Recent Advances in Long Range and Long Endurance

Operation of Aircraft. Neuilly-sur-Seine, NATO-AGARD. p. 16/1-16/10.

Signal L, Gander P, van den Berg M. (2003). Sleep during ultra-long range flights: a

study of sleep on board the 777-200ER duàng rest opportunities of 7 hours. Technical

report. Sleep/Wake Research Centre, Ivlassey University, Wellington, New Zealand,

2003.

Simons, M., Valk, P.J.L., de Ree, J.J.D., Veldhuijzen van Zanten, O.B.A. &

D'Huyvetter, K. (1994). Quantity and quality of onboard and layover sleep: effects on

crew performance and alertness. Report RD-31-94. Netherlands Aerospace Medical

Centre, Soesterberg.

Simons, M., Valle, P.J.L..(1997). Effects of a Controlled Rest on the Flight Deck on

Crew Performance and Alertness. Report: NLRGC 1997-B3. Netherlands Aerospace

Medical Centre, Soesterberg.

Simons, M., Valk, P.J.L. (1998). Early starts: effects on sleep, alertness and vigilance.

AGARD-CP-599; NATO-AGARD, Neuilly-sur-Seine, France. p. 6/1-6/5.

Spencer MB, Stone BM, Rogers AS, Nicholson AN. (1990). Circadian rhythmicity and

sleep of airerew during polar schedules. IAM Report no 679, January 1990.

Spencer MB, Wilson AL, Bunting AJ. The CHS Aleriness Model and the prediction of

perfbrmance. DERA ReportNo DERA/CHS/PPD/CR980191 August 1998.

Spencer MB, Robertson KA. (1999). The Haj operation: alerlness of aircrew on return

flights between Indonesia and Saudi Arabia. DERA Report No DERA/CHS/PPD/

C:R980207 June 1999.

Spencer MB, Robertson KA. (2000). The Haj operation: comparison of the benefits of

in-flight rest in a crew seat and a bunk. DERA Report No DERA/CHS/PPD/CR00008

January 2000.

Spencer Mß. (2002). Modelling of aircrew alertness in future ultra long-range

schedules, based on a city pair. QinetiQ Report No. QINBTIQ/CHS/P&D/CR020047/

l.l, 2002.

Spencer MB, Stone BM, Robertson KA, Hosegood I, I3owell R. (2004). Airerew

alertness on outward and return flights across four time zones. QinetiQ Report No

QINETIQ/Iü/CHS/CR03236/Versíon 2.0, January 2004.

Spencer M, Robertson K. (2004). Aircrew alertness on the Singapore-Los Angeles

route: flnal report. Qinetiq Report no QINETIQ/KI/CHS/CR050022/1.0. Deeember

2004

Scan nummer 3 van 3 - Scanpagina 24 van 25

Ingekomen stukken - 1284
TNO report

25125

Valk, P.J.L., Simons, M., Struyvenberg, P.A.A., Kruit, J. & Van Berge Henegouwen,

ivi: (1997). Effects of a single dose of loratadíne on flying abílity under condieions of

&ÿmulated cabin pressure. American Journal of Rhinology, 1I(1), 27-33.

Vallc, P.J.L., & Simons, M. (1998). Pros and cons of strategic napping on long haul

flights. AGARD-CP-599; NATO-AGARD, Neuilly-sur-Seine, France (pp. 5/I-5/5).

Valk PJL, Simons M, Goei JH, van Hijum SM. (2003). Evaluation of the Fit-to-Fly

Checklist on Long Haul and Short Haul Ftights. Proceedings IS`° EASS --FSF & ERA

Conference "Change: A safety Challenge", March 2003, Geneva, Switzerland. Flight

Safety Foundation, Alexandria, Virginia USA. pp.9-16.

Wilkinson RT, Edwards RS, Haines E. (1966). Performance fbllowing a night of

reduced sleep. Psychonomic Sei; 5(12):471-472.

Scan nummer 3 van 3 - Scanpagina 25 van 25

Ingekomen stukken - 1284