Flyboy's defences consist of Loaders, primarily, as well as a few engineers. There's some Skag resistance in the area as well, but it's light, so come appropriately equipped.
Otherwise this mission is a fairly straightforward run and gun affair. Simply bounce from checkpoint to checkpoint, dealing with the aforementioned enemies. As long as you've equipped yourself with correct hardware, you shouldn't have any issues, this is just a simple series of conflicts. Make sure you're using cover, and leading foes to you frequently.