RE:RE:Moody's rationaleWe can forget the BBB's investment grade Bombardier as a pure player is fully exposed to volatility (for profits) by the Bizjet market, a highly cyclical one. It could not offer the stability asked for an Investment grade rating.
Anyway, too low debt is not a good thing for Bombardier, it is preferable that it has a reasonable amount of debt (enough but not too much) in order to offer a high yield at the top of the cycle.