Required? Didn't know that.
But the backstairs were not used at all during the max pax cerfication evacuation at Hamburg.
[quote author="Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service"]Accordingly, pursuant to the authority delegated to me by the
Administrator, the following special conditions are issued as part of
the type certification basis for the Airbus A380-800 airplane.
In addition to the requirements of Sec. Sec. 25.803 and 25.811
through 25.813, the following special conditions apply:
a. At least one stairway between decks must meet the following
requirements:
The stairway accommodates the carriage of an incapacitated person
from one deck to the other. The crew member procedures for such
carriage must be established.
b. There must be at least two stairways between decks that meet the
following requirements: The stairways must be designed such that
evacuees can achieve an adequate rate for going down or going up under
probable emergency conditions, including a condition in which a person
falls or is incapacitated while on a stairway. One of the stairways
must be the stairway specified in paragraph a. above.
c. Each stairway between decks must meet the following
requirements:
1. It must have an entrance, exit, and gradient characteristics
that--with the assistance of a crew member--would allow the passengers
of one deck to merge with passengers of the other deck during an
evacuation and exit the airplane. These entrance, exit, and gradient
characteristics must occur with the airplane in level attitude and in
each attitude resulting from the collapse of any one or more legs of
the landing gear. These requirements must be demonstrated by tests and/
or analysis.
2. The stairway must have a handrail on at least one side in order
to allow people to steady themselves during foreseeable conditions,
including but not limited to the condition of gear collapse on the
ground and moderate turbulence in flight. The handrails must be
constructed, so that there will be no obstruction on them which will
cause the user to release his/her grip on the handrail or will hinder
the continuous movement of the hands along the handrail. Handrails must
be terminated in a manner which will not obstruct pedestrian travel or
create a hazard. Adequacy of the design must be demonstrated by using
persons representative of the 5% female and the 95% male.
3. The stairway must be designed and located to minimize damage to
it during an emergency landing or ditching.
4. The stairway must have a wall or the equivalent on each side to
minimize the risk of falling and to facilitate use of the stairway
under conditions of abnormal airplane attitude.
5. Treads and landings must be designed and demonstrated to be free
of hazard. The landing area at each deck level must be demonstrated to
be adequate in terms of flow rate for the maximum number of people that
will be using the stair in an emergency. Treads and risers must be
designed to ensure an easy and safe use of the stairway.
6. General emergency illumination must be provided so that--when
measured along the centerlines of each tread and landing--the
illumination is not less than 0.05 foot-candle.
7. In normal operation, the general illumination level must not be
less than 0.05 foot-candles. The assessment must be done under day
light and dark of night conditions.
8. Both stairway ends must be indicated by an exit sign visible to
passengers when in the stairway. This exit sign must meet the
requirements of Sec. 25.812(b)(1)(ii).
9. A floor proximity path marking system which meets the
requirements of Sec. 25.812(e) must be available to guide passengers
in the stairway to the stairway ends. It must not direct the occupants
of the cabin to the stair entrance.
10. The public address system must be audible in the stairway
during all flight phases.
11. ``No smoking'' and ``return to seat'' signs must be installed
and must be visible in the stairway both going up and down and at the
stairway entrances.
d. Cabin crew procedures and positions must be established to
manage the use of the stairs on the ground and in flight under both
normal and emergency situations. This may require that cabin crew
members have specific dedicated duties for the management of the stairs
during emergency and precautionary evacuations.
e. It should not be hazardous for crew members or passengers who
are returning to their seats to use the stairways during moderate
turbulence.
[/quote]
