TA PIS
“ WE CAN THINK OF COMFORT AS AN
ENGINEERING PROBLEM, FOR WHICH
A SOLUTION CAN BE DEVISED”
aircraftinteriorsinternational.com
ANNUAL SHOWCASE 2020 125
1. ULTRALEATHER FEATURES
A FOUR-LAYER CONSTRUCTION
2. THE ULTRALEATHER PRODUCT
RANGE IS DESIGNED, ENGINEERED
AND HANDCRAFTED WITH SOFTNESS,
BEAUTY, AND DURABILITY IN MIND
Lowering the body temperature triggers
the autonomic nervous system to wake
you up as the ‘fight, flight or fright’
response takes over.
This field of study is known as thermal
comfort. Thermal comfort is optimal
when we reach a state called ‘thermal
neutrality’. Thermal neutrality is
maintained when the heat generated
by the human metabolism is allowed
to dissipate, thus maintaining thermal
equilibrium with the surroundings.
The optimum temperature for thermal
neutrality is between 68°F- 72°F
(20°C and 22°C, respectively).
Now that some of the key variables
have been established, we can start
to think of comfort as an engineering
problem, for which a solution can
be devised.
Tapis’ solution centres around the
concept of two key factors. The first is
to make sure that the human body is
properly supported by the skeleton. To
do this, it is important to ensure that
the spine and head are aligned vertically
over the vertebrae of the neck. The
pelvis should be in a neutral position,
not slouched, and the knees should
be at right angles to the thighs.
Achieving the correct height of the seat
bottom and a proper angle ensures that
passengers’ knees are in equilibrium
and at right angles to the thigh and shin.
The seat bottom cushion is critical in
achieving this position. Cushions are
principally made of foam, which has a
measure known as the Indentation Load
Deflection (ILD). This measure shows how
much compression a foam will take under
a given load.
If we estimate the load for a 50-yearold
male, we can soon see how much
height loss there will be from their given
load. Our aim is to suspend the passenger
just high enough to ensure they do not sit
on any of the hard points, such as the spar
tubes or a composite seat pan. If the
cushion height is 3.5in high for example,
the passenger should remain suspended
a minimum of 0.75in above the seat floor
to avoid ‘bottoming out’ and hitting the
hard surface below.
Advanced seat covers, such as Tapis’
Ultraleather, have an inbuilt microfoam
layer that provides a little more height
and decelerates load. The more foam
on a seat, the more the load is dampened
downwards, keeping the passenger
suspended higher and preventing them
from bottoming out.
Related to this, ergonomicists
frequently talk about maximum body
contact when seated. The reason for this
is that the higher the body contact, the
higher the surface area for the same given
load. Since pressure equals force divided
by area, any increase in area will result in
a corresponding decrease in pressure.
The Takumi four-layer construction
technology used in Tapis’ Ultraleather
consists of a substrate, a microfoam layer,
and a top skin layer at the surface, which
conform to a passenger’s unique body
profile. The top skin and microfoam layers
are soft but durable, enabling them to
conform to the body’s shape and create
more surface area contact.
The second key factor is the seat cover
material, as it is a major influencing factor
in controlling the thermal comfort of the
passenger.
Two of the key factors that can affect
thermal comfort are heat and moisture
dissipation. Breathable fabrics are key to
achieving comfort because they contribute
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