FINDING a sea disaster survivor is extremely difficult with air and sea rescue teams having to spot a ''pinprick'' in the ocean, according to the Marine Department search and rescue co-ordinator, Trevor Berry. ''A person's head, which is usually all that is above water, is difficult to spot, even if you are flying at 500 feet [152 metres],'' he said. ''It's like a pinprick, particularly if the sea is anything other than blue and calm, and at sea level, on a ship, your range of vision is very low.'' Mr Berry said the search for 61 crewmen missing from ships which sank during Severe Tropical Storm Becky would continue this morning. The area being searched is about 500 square miles. ''That has to be covered in 20-mile legs, spaced less than half a mile apart, zig-zagging across the sea. That adds up to 1,200 miles, flown as slowly as possible, at about 120 miles per hour. ''The weather can disturb the sea surface and your line of vision. And there is the current, which was disturbed by Becky, but is now reasserting itself, so we have to guess where they have drifted to. ''Preparation for saving your own life is important. In photographs of some survivors arriving at Queen Elizabeth Hospital, there was no sign of a life jacket. ''In the RAF crash, the crewman got out of his aircraft with his one-man dinghy strapped to his back. ''They were in radio contact before the crash so we knew where they were. ''Then there is the fatigue factor for the searchers. They only have to blink and they could miss it [the body or survivor].'' Mr Berry said: ''Bodies submerge for a few days before they bloat and reappear''.