Crowded skies in Southeast Asia put pressure on pilots, air traffic
control
(Reuters) - The sheer volume of flights in the skies over
Southeast Asia is putting pressure on outdated air traffic control and on pilots
to take risky unilateral action in crises such as that possibly faced by AirAsia
Flight QZ8501.
Pilots who have flown the Indonesia to Singapore route say
it's not unusual for delays to requests to increase altitude to avoid bad
weather - and for requests to eventually be rejected due to the number of other
planes in the area.
That leaves pilots flying in a region of volatile
weather conditions facing a high-risk challenge: when to take matters into their
own hands and declare an emergency, allowing them to take action without getting
permission from air traffic control.
Most consider that step - which
requires them to broadcast a wideband call to other aircraft in the area and
which will later be closely scrutinized by regulators - a last
resort.
"As a professional pilot, you are obligated to think quickly," a
Qantas Airways pilot with 25 years experience in the region told Reuters. "If
you've signed for the plane, as we put it, you've signed for potentially 300
passengers and millions of dollars worth of aircraft; that's a multibillion
dollar liability. Part of the job is to balance the risk and make a snap
decision."
Weighing those risks has become increasingly difficult in
Southeast Asia, an area that has seen explosive growth in budget air travel in
recent years.
The number of passengers carried annually across
Asia-Pacific has jumped by two-thirds in the past five years to more than 1
billion, according to the Centre for Asia Pacific Aviation. Budget airlines,
which only took to the skies around a dozen years ago, today make up about 60
percent of Southeast Asia's seat capacity. AirAsia and Indonesia's Lion Air have
placed record orders with the main plane makers.
Boeing predicts the
region's airlines will need about 13,000 new planes over the next two decades,
and Airbus expects Asia-Pacific to drive demand over that
period.
LOGISTICAL NIGHTMARE
"There are certain flight corridors
that are over-stressed due to traffic," said a former Singapore Airlines (SIA)
pilot with a decade's flying experience at the carrier. "One certainly would be
the Indonesia/Singapore flights which are flown by many different companies and
aircraft types at a variety of altitudes and speeds."
Pilots say that
causes a logistical nightmare for the region's air traffic control (ATC),
particularly outside high-tech hubs such as Singapore.
"As the airways
become more crowded, it takes ATC longer to coordinate and give clearances such
as higher altitudes and weather deviations," the former SIA pilot
said.
This can be critical in a region where weather conditions can
change very quickly, with strong winds and tropical thunderstorms posing
time-critical challenges for pilots.
The circumstances around the AirAsia
crash are not yet known, but investigators and the airline's chief Tony
Fernandes have pointed to changeable weather being a significant
factor.
The Association of Asia Pacific Airlines said last month that
while airlines were investing heavily in fuel-efficient planes to meet rising
demand, there was growing concern about the need to also invest in related
infrastructure, such as airport terminals, runways and air navigation
services.
OUTDATED EQUIPMENT
To keep aircraft traveling in a
flight corridor at a safe distance from each other, air traffic controllers in
Indonesia employ procedural separation - where they use pilots' radio reports to
calculate their position relative to other traffic.
That takes longer
than the more sophisticated radar separation used in Singapore and elsewhere in
the world, which allows a controller to more quickly take stock of radar returns
from all aircraft in the area.
A lack of up-to-date equipment and
volatile weather conditions were cited by pilots and aviation experts in the
2013 crash of a Lion Air Boeing 737, when the pilot reported the plane being
"dragged down" by wind into the sea just short of the runway.
That was
considered a classic example of wind shear - the sudden change in wind speed and
direction. Airports in the region's popular island resorts, including Bali, Koh
Samui, Langkawi and Cebu, don't have on-ground wind shear detection equipment to
help pilots land and take off. [reut.rs/1D4SLcj]
Pilots said critical
decisions often come down to experience.
"In my opinion, if I don't get
permission (to change course) and there's weather ahead, I'll just deviate and
deal with the authorities later," said another former SIA pilot who is now with
a Gulf carrier.
Flygbolaget Air Asia har drabbats av ytterligare en olycka, bara tre dagar efter att flight QZ8501 störtade.