I'm surprised that making aircraft are is low impact. Things like smelting aluminium are pretty bad. However there is more to a plane than aluminium and more to US industry than aircraft.
The airplanes don't so much have low impact, rather they have a high sales price. Divide it out and it works out well enough. Airplanes have a lot of IP going into them.
Also, there is a good reason Boeing setup originally in Seattle. The smelting of aluminum is much cheaper when an abundance of surplus hydroelectricity is available.
Smelting wouldn't really count as an environmentally friendly activity, but having a relatively low impact source of electricity helps. Interesting regarding their location, thanks.
