On a small chartered plane, I flew around the search area where coastguard cutters and US naval vessels are trying to find bodies and chunks of wreckage from Egyptair 990.

This is no longer a rescue mission, it's a recovery operation.

Officials say no one could have survived in the chilly waters here for more than five or six hours, so they have confirmed they're not now looking for survivors.

Admiral Larrabee of the US Coastguard: No expectation of any survivors

In their hearts, the rescue teams must have known this almost as soon as they started looking: The Boeing 767 literally fell from the sky, plummeting down with such awesome velocity that no one could have come out of it alive.

From the air, this part of the Atlantic looks breathtakingly beautiful.

The sun has been shining brightly all day, the skies are clear and the waters calm. In short, conditions for the search teams have been ideal.

Problems for the investigators

The problem is that much - probably most - of Flight 990 is underwater, and deep underwater at that.

The ocean bed is 270 feet in this area: retrieving wreckage from so far down will be a logistical nightmare, so they're bringing in the American salvage ship, USS Grapple, which has sophisticated sonar detection equipment that can locate even the smallest pieces of debris.

A coastguard station in Nantucket

On Nantucket island, the closest landmass to where the plane came down, local residents are preparing a much less sophisticated search operation of their own.

They believe that within the next few days, bits of wreckage - and maybe bodies too - will be washed ashore. They've been told to report anything they come across to the police as soon as possible.

There's no doubt that investigators need every clue they can get their hands on to unlock the mystery of what happened to the Egyptair flight.

The mood among the myriad of officials here - FBI, Coastguard, Navy, National Transportation Safety Board - is understandably subdued and very cautious.

No hasty conclusions

No one is in any hurry to come to any hasty and possibly unfounded conclusions.

With the TWA crash a few years ago, many wrongly blamed the disaster on terrorism.

Hamdi Hanafi, father of 22-year-old Walaa Hamdi, one of the victims, is to fly to the US

While sabotage is not being ruled out in this case, it doesn't look likely and certainly no one has made any claim of responsibility.

If it's some kind of mechanical or structural problem that's to blame, no one in authority here is speculating about that either.