SINGAPORE - Twenty-four volunteers from the Republic of Singapore Air Force climbed on board two military aircraft on Monday to help look for the missing AirAsia QZ8501 flight.

One plane left Paya Lebar Air Base at about 6.30am on Monday, while the other left the base a few hours later at about 12.40pm.

The volunteer scanners' task was to look for any sign of the missing AirAsia plane, such as wreckage or oil spills from a crash.

But the work was slow and painstaking, The Straits Times found out when it joined the earlier mission.

The total search area allocated to Singapore is 60 nautical miles by 190 nautical miles - about the size of 546 Singapores - within the Java Sea.

The first flight on Monday covered about 15 per cent of this search area in 5 1/2 hours, in an area 400 nautical miles southeast of Singapore. It flew about 81/2 to 9 hours in total, including travelling to its search area.

All possible leads on Monday however turned out to be debris, possibly rubbish from fishing boats, and not aircraft parts.

Since the flight disappeared en route from Indonesia to Singapore on Sunday, the Republic has set aside the two C-130 transport planes, three ships and other resources to help find it.

The second flight is expected to cover another 15 per cent in about the same time. In total, Singapore was expected fulfil 30 per cent of its commitment on Monday.