Question: At the end, how were they supposed to rescue Katniss inside the dome? Because her shooting the wire at the dome just as the lightning struck couldn't have been their plan all along? It just seems like a lot of risk for them getting into the flying machine and waiting outside waiting for her to figure out how to incapacitate the dome and to actually manage it.
Answer: Gamemaker Plutarch, who is on the side of the rebellion, made sure that there was the 'lightening tree' and suitable wire for Wiress and Beetee, who had enough knowledge of electricity and forcefields to find a way to destroy the dome, so that was probably plan A all along. Beetee had a spear with the wire attached to throw at the forcefield, but then got injured, and Katniss just finished his plan.
Answer: Whatever the plan to remove Katniss from the arena was, which was never revealed, it was circumvented by her shooting the dome ceiling with an arrow.
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