Consider the case of two Cessna Ag-Truck pilots.

The Ag-Truck is a crop-dusting aircraft, designed to spray chemicals on crops. It's much like any other plane except for a giant hopper built into the fuselage just in front of the cockpit. But it's really more fun to fly an Ag-Truck plane than most planes. You are alone in the aircraft; with a fuselage just wide enough for a single seat, you sit on the center-line of the aircraft, not off to one side as you would in a plane with car-like seats. The canopy surrounds you with an unobstructed view of the horizon in every direction. And you get a control stick, not a control wheel which looks very much like a steering wheel in a car.

The Ag-Truck takes all the differences between a itself and a "normal" plane and maximizes them. No wonder it's called the "Poor Man's P-51." You can't get closer to that legendary fighter aircraft with anything else that is available to civilians.

But it isn't meant to fly over oceans. The fuel tanks hold only 50 gallons which will get you about 300 miles, leaving you 2000 miles short on a trip to Hawaii. That's where the chemical hopper comes in. With a little plumbing, that 250 gallon tank can be filled with fuel which is then routed to the engine.

There's another problem as well. The plane is slow. It will take at least 18 hours to get from Oakland to Hawaii and probably more. That means some of the flight will take place at night. Night flying over land is aided by lights on the ground which allow you to tell which way is up. They won't exist over the ocean so you are obligated to provide you own local horizon in the plane. This is done with an instrument called an artificial horizon. It is powered by a vacuum pump attached to the engine.

But that's not the last problem. There's no space for luggage. There is a small panel on the side of the fuselage that you can remove with a screwdriver. That gives you access to the cables running to the control surfaces at the rear of the plane. A small gym bag can be placed there, but only if some care is taken to fasten it down. If it moves in flight and gets caught in the controls, you could be in serious trouble.

Two items need to be considered beyond the normal flight-bag charts: a life raft and an HF radio. A two-man life raft, suitable for bobbing around in the ocean long enough for someone to come along and fish you out, folds into a package about the size of two loaves of bread. The HF radio, designed to allow communication beyond the range of the "normal" aircraft radios, is about the same size.

The life raft must go in the cockpit. Putting it in the tail where tools are required to retrieve it wouldn't allow quick access in an emergency. But that's where the HF radio needs to go as well. Real estate is at a definite premium here.

So how does this sound for a solution for a flight of two identical Ag-Trucks? Let one take a radio and the other take a life raft. Only one radio is actually needed, as the position report can be made for the flight of two as long as they are together. And the owner of the raft will have it conveniently available if he needs it and could easily throw it into the water near his swimming partner if the other plane had to ditch.

It sounded good on paper, so the flight of two launched from Oakland enroute to Australia. The leg to Hawaii went OK but the next leg did not. The plane which did not have the raft developed trouble which could not be corrected in flight and was forced to land in the ocean. "Not a problem," you say. That was covered by the plane which had the raft available. All that pilot had to do was open the window and drop the raft near his companion.

The plan would have worked satisfactorily during the day.

At night the ocean is black and the sky is black. They merge so seamlessly it's hard to tell how far from the water you are. Throw your raft anywhere you want; in the dark, you'll never see it again.

Neither will the pilot who is waiting for it.