Big Green Double Trouble

I did a standard definition video of these two behemoths double-headed about three years ago, so it was only a matter of time until I redid it in hi-def.  Here they are, the two big green monsters of the rail, the Great Northern Z-6 Challenger (4-6-6-4) and the R-2 Chesapeake (2-8-8-2) articulated steam locomotives in True HD 1080p.  They're running double-headed and hauling a long unit train of woodsided reefers which, since everyone has seen them all in previous videos, I've cut short so you can enjoy the sound and fury of the locomotives.