Stormy, rainy weather over Southeast Asia could hamper the search for the missing Indonesia AirAsia Airbus A320 aircraft.

Flight QZ8501 lost contact with Indonesian air traffic controllers this morning at 07:24 Singapore time while operating the Surabaya-Singapore route.

Before its disappearance, it had requested a change in flight plan owing to inclement weather. Imagery on weather reporting site Accuweather suggests overcast, stormy conditions at the time of the aircraft’s disappearance.

Indonesian officials have said the last known aircraft coordinate was 03 09 15 S and 111 28 21 E. This coordinate places the last known location of the aircraft about 16nm south of West Kalimantan, an Indonesian province on the island of Borneo.

Media reports have cited Indonesian officials as saying that the search and rescue (SAR) mission has commenced, but the precise search area and assets deployed are not yet clear.

Although visibility could hamper the efforts of SAR aircraft, the onset of nightfall is of more imminent concern. During the initial search for MH370 over the Gulf of Thailand, regional search aircraft generally did not operate at night.

Flightglobal’s Ascend Fleets database shows that a number of regional assets should be available for the search.

In the scenario that the missing aircraft has crashed into the sea, the Indonesian navy possesses six Airbus Military C212 maritime patrol aircraft (MPA), three CN235 MPAs, and over two dozen N22/24 Nomad MPAs. It is not clear, however, how many of these assets can be deployed for an aerial search before nightfall on 28 December.

Indonesia also has a range of military and civilian helicopters that could be deployed in a search.

Singapore has already committed to Lockheed Martin C-130s should Jakarta request any assistance. Singapore also has five Fokker F50 MPAs, which could quickly contribute to the search operation.

During the immediate aftermath of the MH370 disappearance, when a major search was underway for the missing 777 in the Gulf of Thailand, an expert in airborne search and rescue told Flightglobal that technology is of limited use in searches for downed aircraft.

In an air crash on the sea, debris would typically be relatively small and floating low to the surface, making it very hard to "paint" with radar. Additionally, floating debris has no Doppler speed relative to the surrounding ocean, so it would typically be filtered out by radar software intended to de-clutter the radar display.

“Turning off that feature would create a massive amount of clutter and sporadic returns, not adding much value,” he said.

Electro-optical/infrared (EO/IR) sensors could be of some utility at spotting debris, but any floating debris will have to be considerably warmer than the surrounding ocean.

“The best sensor for SAR remains the human eye, which is why maritime patrol aircraft are all designed with the ability to fly low and slow to detect survivors or small debris,” he said.

Source: Cirium Dashboard