"I will be neither surprised nor shocked if the lawsuits also name American Airlines, which has no protection obviously under the FTCA. It didn't do anything wrong ..."
Well presumably any lawsuit naming American Airlines will have to allege they did something to incur liability. The only such theory I can come up with is that the jet pilot should have refused the rerouting to runway 33 because he should have known that would increase the jet's exposure to reckless helicopters. Which is sort of blaming the pilots squared. Is that what you want to go with or do you have an alternative way of dragging American Airlines into this? Of course American Airlines is already involved in that they have a FTCA claim against the government for at least the value of their plane.