Sterile Flight Deck - One of Aviation's Mysteries

Sterile

Flight Deck
- One of
Aviation's

Mysteries

Compiled by Captain Andrew
Poulsen & Or Graham Edkins

Likaedopmteadny aai'srltineerilse, fQligahnttasdechkas Why do we have a "Sterile Delta 1141 accident in 1988, where
Flight Deck" Policy? the flight crew became distracted
policy' as standard operating with a flight attendant in the cockpit
practice. A sterile flight deck is a The departure (taxi, takeoff, and failed to extend the flaps for
period of limited or no contact departure) and arrival (approach, takeoff.
between cabin crew and flight landing, taxi) periods are critical
crew. A recent survey of Qantas phases of flight that involve high It must be stressed that safety
cabin crew by the Corporate workload for flight crew. Distracting related communication outside the
Safety Department has revealed the flight crew with non safety- no contact period is always
some misunderstandings about related issues during these periods, acceptable and should be
the sterile fight deck policy, and can lead to the omission of encouraged. This was highlighted
its importance within aircraft on one of our own Qantas aircraft
operations. The survey findings important tasks such as obtaining when cabin crew alerted the flight
coincide with Safety Observation clearances to cross active crew to an unusual noise under the
Reports (SOR's) and Air Safety floor during taxi for departure. The
Incident Reports (ASIR's) that runways, the correct read back of aircraft returned to the gate, where
have been submitted as well as altitude restrictions and the correct it was found that several containers
anecdotal evidence that in the cargo hold had not been
continues to be received from completion of checklist actions. properly secured.

crew during line monitoring and An historical analysis of aircraft The policy explained
normal operations. accidents has revealed that most
occur during the takeoff and The sterile flight deck policy is
This article outlines the rationale landing phases of flight. While detailed in the Aircrew Emergency
these two phases of flight represent
for having a sterile flight deck only 4% of journey time, they
policy, details our current correspond to 70% of all aircraft
procedures, and discusses the accidents (Flight Safety Digest,
results of the cabin crew survey. 1994). To minimize flight crew
It is hoped that this information distraction during these high
will promote discussion and workload and high risk periods,
awareness of the importance of Qantas has developed an additional
sterile cockpit procedures no contact period. Non-adherence
amongst all crew. to the no contact period can be
disastrous as was shown in the

4 Flight Safety

Procedures Manual (03.50.1-2). + Passenger problems. Eg., responses cannot be made.
There are two parts to the policy:
(1) no contact periods and (2) people refusing to sit for take Making contact with the flight crew
contact for safety related issues. off, violent behaviour or during the sterile period to pass on
Outside of the sterile flight deck disruptive passengers (CASA passenger requests, or inquire
periods, normal communications regulations ); about onwards flight details,
are permitted. The following connections or arrival gate
illustration from the Flight Training + Unusual noises or vibrations; information is not acceptable.
Department outlines the policy. + Medical problems; These are not safety-related issues.

Embedded within

these flight sequences
are no contact

periods, which
coincide with the

highest workload/risk
segments of takeoff
and landing. During
departure, the no-

contact period

operates between the
commencement of the

takeoff roll to gear up.
During arrival it
operates between

gear down till the

All runway is vacated or
the aircraft has
Communication
stopped on the

eo« 20.000 FT. AIrc,.., flopS A":;''"' runway. Contact with
PA or tums on ''''''''''"
Clo ••••• acl!ye the flight deck for any
reason during this
c!m~.l_I~r.lfU ""1WIIY

On departure, the sterile flight deck period is not
period commences when all doors
are closed and ceases when the permitted, as
seat belt sign is switched off after
takeoff. On arrival it commences + Information associated with the distractions can
with the cabin preparation PA and
concludes when the aircraft arrives seat belt/turbulence policy; disrupt the flight crew at a critical
at the terminal. During these times time.
the flight deck can only be
contacted for safety related + Problems securing the cabin Even if an attempt was made to
issues. What are some examples contact the flight crew during the no
of safety related issues? for landing. Eg., service not contact period it would most likely
completed, meal trays not be ignored because of the
At any time, on the ground or in the collected, or carts not secured increased workload and
air, with the exception of the no (CASA regulations); and
contact periods, the flight crew will prioritisation of tasks. Repeated
need to be informed regarding: + Anything that might affect the calls could become an operational
hazard. In some circumstances,
+ Smoke or fire anywhere inside safety of the operation.
the flight crew may even be dealing
or around the aircraft fuselage; The above list of safety related with the problem being reported.
issues is not exhaustive. Flight Contacting the flight crew (for
crew will not necessarily be aware safety related issues only) would
of these issues, so it is vital that have to wait until after the
any information be forwarded
promptly. Unless flight crew are "in undercarriage was retracted
the loop", effective and efficient (departure) or the aircraft stopped
or turned off the active runway
(arrival).

It can sometimes be difficult to In the survey, cabin crew were
determine the position of the asked to indicate in what situations
undercarriage unless cabin crew
are sitting directly over it, making they would contact the flight deck
delineation of the no contact during the sterile period. For
period problematic. On departure example, 30% of surveyed crew
the landing gear is retracted soon would not contact the cockpit for a
after becoming airborne, which
makes identification easier. major medical emergency while the
However, on arrival the sound may aircraft was taxying for departure.
be less distinct. As a general rule Additionally 47% felt it unnecessary
of thumb, the illumination of the to contact the flight deck for a
seat belt sign is a good indication disruptive passenger. Yet 98%
that the aircraft is not far from gear have no reservations about
extension and the beginning of the
no contact period for landing. contacting the cockpit during taxi
for departure for smoke in the cabin
Cabin crew sterile flight deck or fire or smoke in an engine. There
policy survey results
appears to exist a level of
During February and March 2001, a reluctance by some crew to relay
cross section of long and short important safety related information
haul cabin crew were surveyed to to the flight crew during the sterile
collect information about the flight deck periods. This might be
following: because of misunderstandings
about the policy itself, fear of
+ their knowledge of sterile flight violating the policy or differing
opinions on what represents a
deck procedures, and safety related issue.

+ the types of situations which procedures with 6% identifying the The vast majority of cabin crew
arrival of the aircraft at the terminal, surveyed confused sterile flight
they considered contact with deck procedures with the no
the flight deck should be as its conclusion. Flight crew have contact period. This may well
made. reported that cabin crew explain the reluctance of some
occasionally enter the flight deck crew to contact the flight deck
Cabin crew were surveyed face to under certain circumstances. Also
face in sign on and crew room (or call via interphone) after the evident were misunderstandings
locations. Those that responded, arrival PA has been made, or even about the no contact period,
varied in their length of service from highlighted by 40% of surveyed
3months to 32 years, with an during taxi to the arrival gate, to crews indicating that they would
average of 12 years. enquire about passenger contact the flight deck during the
connections, gate information or no contact period. In other overseas
The majority of those surveyed, felt landing times. These are not carriers, cabin crew have failed to
that they had never violated the safety related issues and are report smoke, toilet fires, unusual
sterile flight deck policy. However, violations to the sterile flight deck noises and vibration and changes in
very few of the surveyed crew could cabin pressure for fear of violating
accurately identify when sterile procedures. The above survey sterile cockpit procedures or as a
flight deck procedures began and results may help to explain the result of misunderstanding the
ended. For example, 61 % identified reason for the vast majority of procedures.
the "seat belt sign off" as the end of sterile cockpit violations.
sterile procedures after departure, In Summary
yet only 11% identified "doors
closing" as its beginning. Only The survey, together with formal
22% correctly identified the "arrival reports and anecdotal evidence,
PA"as the beginning of the sterile clearly indicates that there is a
misunderstanding by many cabin
crew about sterile flight deck
procedures. Cabin crew are a vital

6 Flight Safety

resource and are the eyes and reliance on clear and concise NB. This lATA report may not reflect
ears of the aircraft cabin. Anything interphone communications. From a Qantas Policy.
unusual that can have the potential human factors perspective, the reliance
to affect safety needs to be on the interphone as a communication About the Authors
reported to the flight deck as soon medium can create a significant barrier
as possible. These circumstances to the effective flow of information, since Captain Andrew Poulsen is the CRM
are allowed for in the sterile flight facial expressions and gestures are Coordinator in Melbourne and a
deck policy. hidden. In an abnormal situation, it is member of the Flight Training Human
recommended that the person with the Factors Working Group. He has a
All crew should refamiliarise information, coordinate the degree in aviation studies and is a
themselves with the policy, communication to the flight deck via the Check and Training Captain on the
especially the communication interphone, to avoid filtering or B737 fleet.
restrictions concerning the "no misinterpretation. The information
contact" and "safety related issues" conveyed should be accurate, Or Graham Edkins manages the
contact periods. This policy is for unambiguous and succinct. development of human factors
your safety and the safety of the initiatives across the Qantas Group and
travelling public. Please refer to the warning below from is the Australian representative on the
the International Air Transport lATA Human Factors Working Group.
EDITORS NOTE: Restricted Cockpit Association (lATA) Human Factors
Access: Recent security changes to Working Group about the potential
cockpit procedures now place a effects of aviation security changes on
aircrew human factors.

FROM THE 2001 lATA SAFETY REPORT

A word of caution from the lATA Human Factors Working Group (HFWG) about proposed aviation security
initiatives

At the recent lATA Operations Committee (OPC) meeting in Montreal on 2-3 October 2001, the subject of security
enhancements dominated the agenda. This discussion came in the wake of the events of September 11, which
have had a profound effect on the aviation industry. One of the agreed outcomes of the meeting was the formation
of the Global Aviation Security Advisory Group (GASAG), which aims to provide a coordinated industry view
towards global harmonisation of security procedures. GASAG have since commented on a number of initiatives in
regard to aircraft security and flight procedures; namely:

+ Reinforced and restricted access to cockpit doors;
+ Transponder alert;

+ In-flight security personnel (Sky Marshals);
+ Installation of cameras to monitor passengers;
+ Weaponry/Combat training for aircrew;
+ Aggressive flight manoeuvres and depressurisation; and
+ Enhanced ground/airport security.