Is it practical to use ground effect to extend range in an emergency? Imagine a piston engine airplane (let's say a DC-3) flying at cruise speed and altitude over a calm sea, trying to reach an unreachable airstrip straight ahead, just above sea level. Fuel is very low and ditching may occur at some point even if highest lift to drag to consumption ratio is achieved.

Would a ground effect low horizontal flight increase the range? That could mean ditching closer to the shore, and getting help sooner (or even landing safely).

If yes, is it also the case for a modern jet airliner usually cruising faster and in a much thinner air, and are there some emergency procedures or regulations about that?
When flying close to the ground, there is an important reduction of induced drag, the larger the closer to the ground one flies, so the airplane needs less engine thrust to keep a given airspeed. Anyone who has made a low pass over a long runway may attest this...

Flying in ground effect is a nice way to save fuel and extend the range. I remember reading that it was often used by carrier planes returning from a mission low in fuel...