In season three of Lost, both Kate and Sawyer were chain ganged by the Others into helping construct/clear a runway.
At the time, I had assumed that the Others were planning on creating an alternative transportation method in addition to the water-based routes. In the fifth series however, Frank Lapides was able to crash land the Ajira flight on the runway, thus allowing most of the passengers to emerge unscathed.
Is it possible that in 2004 Jacob ordered the Others to construct the runway in preparation for the Ajira flight that would crash there three years later?