Why is that?

These are essentially the most critical components from a specification and demand perspective on the engine. They are rotating components with high performance and metallurgical expectations. You need to get them right the first time from a manufacturing capability standpoint. There are probably very few manufacturers globally with that level of capability.

That doesn't include the labor to run it. That's just the capital expenditure to get it up and running.

Correct. It's a very knowledge-based process, almost like tribal knowledge to a certain extent. Even if you're determined to start a greenfield or a startup in this field, you'll be forced to poach people from your competitors. There's no way around it. When you look at it from a technology or IP perspective, you rarely see patents. It's very much process IP-driven, internal, and companies will defend themselves aggressively from a legal standpoint if they feel someone is taking that knowledge outside.

Like what, exactly?

For instance, the profile or ramp-up in temperatures used to heat treat a product or pour a part properly is very specific. You need to ramp up at a certain speed and temperature profile.