On 16 September 2006 at 0038 Western Standard Time, an Airbus
Industrie A330 landed on runway 21 at Perth Airport in weather
conditions that were below the applicable landing minima. The
aircraft, registered VH-QPJ, was being operated in accordance with
the instrument flight rules (IFR) on a scheduled passenger flight
from Singapore to Perth, WA.
Before departure from Singapore, the aerodrome forecast (TAF)
for Perth Airport predicted a 30% probability of fog after 0200.
The aircraft was due at Perth at 0020 so in accordance with the
operator's fuel policy; fuel was not specifically carried for a
diversion from the destination to an alternate aerodrome. While the
aircraft was in cruise, the TAF was revised to forecast fog from
2400, but the trend type forecasts (TTF) which superseded the TAF
trended fog from 0030.
At about 2350, when the flight crew commenced descent, the
aircraft passed the point where it had the fuel to divert to
Learmonth, WA. About 10 minutes later, the TTF was amended to
forecast fog to occur before the aircraft's arrival time. The fog
occurred at about 0015. The crew attempted two Instrument Landing
System (ILS) approaches before they used autoland to land on runway
21 in weather conditions that were below the prescribed landing
minima for the ILS
The ILS at Perth (and other Australian airports) was approved to
the Category I standard that did not allow landings where the
visibility was less than 800 m. The Perth runway 21 ILS glide path
critical area was not fully protected from multipath effects during
low visibility operations.
Perth and Learmonth were the only aerodromes in Western
Australia that could be classified as suitable for the A330, and
Learmonth was 599 NM (1,110 km) from Perth.
As a result of this occurrence, the operator implemented an
interim flight planning fuel policy specifically for Perth.
