Air Force One friction welding blade-to-disc program

Failed Air Force program to friction-weld blades to large discs. The unrealized 20-lb-per-disc / 200-lb-per-engine / 2000-lb-per-airframe weight-cascade is Tom's thesis statement on how single-component savings propagate.

The Air Force had a big program to do friction welding of blades to discs, great big ones, and it never worked out. You can take my welding course and I'll tell you more about it. The idea was you could save twenty pounds off every disc, and that could be two hundred pounds on an engine. If you could save two hundred pounds on the engine — you have multiple engines on many of these aircraft, at least if it's Navy rather than Air Force. The Air Force doesn't mind having only one engine and losing aircraft; the Navy likes to have an extra engine.