Millerscourt
Most of the Tridents were made after HSA had dropped the de Havilland name but that doesn't mean it wasn't a DH type number when originally designed, that number having been used from the (Airco) outset.
Rocket2
The offset was so that the gear could retract sideways thus having a short but wide bay and permitting a bigger avionics bay behind it. A conventional nose gear bay would have left a couple of long thin voids either side which would have been difficult to access so little use for the avionics of the day.
ETA
Oh and although I'm not a structural engineer I'd say the pressure floor required is shorter, so easier to support .
Last edited by Allan Lupton; 3rd Jul 2013 at 10:10.