If the blades makes it past the containment thingy, a sheet of aluminium isn't gonna do much.
In July, uncontained engine failure on Delta Flight 1288 in Pensacola, Florida, killed a mother and her 12-year-old son when the engine disintegrated, hurling metal blades through its casing and into the passenger cabin.
The safety brief should include that those in the row next to the donk should go the whole flight with their legs tucked under their arses just in case...