I worked on a helicopter operation in the Middle East that required us to land and shut down on an offshore rig with only one helideck and was a two day round trip by boat otherwise.
The pilots underwent a short course of instruction on changing the igniter plug, should we fail to get a start on the rig, we carried the spare and the tools. The only other job we could do was top up the floats with air, should it be required.
Everything else was/is strictly engineers territory.