Supplying Midway and using its patrol radius

If Japan had captured Midway, how could it have supplied the island and what would the base have provided?

Japan expected to run convoys and would probably have relied heavily on supply submarines; Midway's main value would be an airfield extending reconnaissance and patrol coverage across a large area of ocean.

Convoys were the expected supply method, with supply submarines judged likely to be critical. The island's main operational value was information gathering from patrol aircraft. Before satellites and routine aerial refuelling, an island airfield extended the part of the ocean that aircraft could search. A rough patrol-radius estimate allocates a third of the aircraft's flying range outward, a third to patrol, and a third to the return flight.