What I Learned Today

[BigV]

During the development of the engine for the 777, there were a series of shows about its design, development, testing, etc. There were many shows and one of them, on the engine, had a segment that featured that retaining ring. It showed in extreme slow motion the result of many different insults. They fired a frozen turkey into the spinning turbine blades (sliced frozen turkey, in case you were wondering), they tried to drown it with enough water to simulate storm that dumped 22" of rain (boring. wet.) and they showed what happened when a designated turbine blade came loose. That was interesting. It was painted white, and when it came out, it moved outward from the center of course. But the clearance was so slight that it immediately collided with both the inside of the shroud and the turbine blades following it. Several broke and the whole mess of them continued their outward path. One camera angle was from outside the engine looking at the spot where the blades would have come out (in the absence or failure of your band) and all we could see was a little movement under the fabric, as if something were moving under a sheet. Then nothing.

Until now I hadn't understood what was going on there that produced the effect I saw. Now I know more, but I'm just as amazed.