Why Were the "Center Seats" Too Cold? — The Evolution of AGT Air Conditioning Breaking Through Ceiling Constraints

Stepping into a cooled train car in the

middle of summer is truly a blissful

moment. However, in early two-door

Automated Guideway Transit (AGT)

vehicles, passengers often complained

that one specific spot was "too cold":

the center seats. This was caused by

a mismatch in the air conditioning

system—a remnant left behind as

vehicles evolved from one-door to

two-door layouts.

Before the arrival of two-door cars on

lines like the Yurikamome, the

standard for AGT was to blow cold air

from both ends of the vehicle toward

the center. This was actually a rational

design for one-door cars, as the cold

air would converge and drop down

over the central door area, which was

the most crowded part of the train.

However, once the layout changed to

two doors, that central area became

a seating section, meaning cold air

began hitting seated passengers

directly.

While a duct-based system was the

ideal solution to distribute air, it was

long considered "physically

impossible" due to the low ceiling

height characteristic of AGT vehicles.

This barrier was finally broken by the

"side-discharge" duct system adopted

in the second-generation Yurikamome

vehicles. By venting cold air sideways

through ducts along the edges rather

than blowing it straight down, the

system cools the interior uniformly

without hitting passengers directly.

This small adjustment in airflow

fundamentally redefined AGT comfort.

Interestingly, this "fix for two-door

cars" took an unexpected turn.

The uniform temperature distribution

was so comfortable that demand for

the same system grew even for

one-door cars, which previously had

no reported issues. Its adoption in the

latest models, such as the Astram

Line 7000 series and the Leo Liner

00 series, is more than just a

horizontal expansion of technology. It

marks the moment when the entire

AGT infrastructure began to pursue

the "ideal interior environment,

" regardless of vehicle type.

Technology is being used to eliminate

the inequality where comfort depends

on where you sit. Might this evolution

of the duct system be seen as one of

the "sincere answers" for urban

transportation? The gentle air that

avoids direct skin contact is an

expression of a design philosophy 

that strives to stay close to every

single passenger. The next time you

find the entire car perfectly and

uniformly cool, remember it may be

thanks to the "invisible hospitality"

hidden behind the ceiling.

I hope you look forward to the next

AGT Blog!