Mode 5, all speeds - high altitude. The
drogue bridle remains connected until the seat has
descended to 18,000 feet. This arrangement
prevents prolonged exposure to low temperature
and thin air and enables the occupant to ride down
in the seat, controlled by the drogue and supplied
with emergency oxygen, to a more tolerable
altitude. The seat attitude will be horizontal with
the occupant facing down. When the seat has
descended to 18,000 feet, the drogue bridle is
released, the parachute deployment rocket motor
fires to deploy the personnel parachute, and the
harness release system operates to free the
occupant from the seat. The occupant is momen-
tarily held in the seat bucket by the sticker clips.
All modes. The personnel parachute, when
developed, lifts the occupant and survival kit from
the seat, pulling the sticker lugs from their clips.
This arrangement ensures that there is no
possibility of collision between seat and occupant
Learning Objective: Identify the organiza-
tional-level maintenance philosophy for
the NACES system.
The primary task of maintenance technicians
is to keep the systems they are responsible for in
an operational condition. To achieve this goal,
the technician must be proficient in the
maintenance, removal, installation, testing, and
adjustment of system components. All of this
must be performed in accordance with applicable
technical publications. Most importantly, all these
functions must be done safely.
Ejection seats and associated components are
carefully designated, manufactured, and tested to
ensure dependable operation. This equipment
must function properly the first time. Malfunction
or failure to operate usually results in severe injury
or death to crew members. You must always use
the utmost care in maintaining escape system
equipment. Strict compliance with the
maintenance procedures presented in the MIMs
and the maintenance requirement cards (MRCs)
are mandatory and cannot be overemphasized.
NOTE: The information presented in this
chapter must NOT be used in place of
information provided in the MIMs.
With the increasing use of diverse and exotic
(composite) materials in the manufacture of
aircraft components, it is imperative that the
proper methods and materials be used to prevent
and/or correct corrosion. NAVAIR 13-1-36,
Organizational Maintenance with Illustrated Parts
Breakdown Manual, has been developed to
provide specific instructions and repair actions for
NACES seat components. It is an in-shop manual
written to provide the most complete and
technically correct information available to the
maintenance technician in one publication.
Remember, these manuals are your primary
source of maintenance information.
The Martin-Baker Navy Aircrew Common
Ejection Seat (NACES) represents the very latest
in escape system technology. It has been designed
to provide maximum personnel survivability, a
high level of escape comfort, total reliability, and
ease of maintainability. For the first time in this
field, the power of the microchip has been
harnessed to give the seat the unique ability to
respond to the variable demands of an ejection
situation in a manner far more flexible than was
possible with earlier mechanically controlled seats.