cool, a nice find Jeff, im ordering a pair of those myself 
hmm I wonder what type the RN. intended dropping them from 
I purchased four of the things in 1:48th scale two weeks ago. They were delivered last week and are waiting for me to pick up at my brother's place in town. :)
As far as the delivery platform, who knows for sure what they had planned for delivering the weapon. It might have been a situation where the bomb was built without consideration to what platform would carry it. The fact that the USAAf was given the mission and the B-17 was able to carry the things externally does not mean that it was for ever and written in stone that the weapon would be carried internally but perhaps it was with caution that the weapon was carried externally since there were rocket motors in the thing that if ignited inside of a bomb bay might have caused a catostrophic mishap in flight or on the ground. That the B-17 did carry the weapon and managed to drop it in action says a lot about the versatility of the aircraft. I do wonder if the RAF would have considered any kind of external rack for the weapon so that it could be carried on the Lancaster under the wing between the fuselage and inboard engines? Would the racks have been similar to what was mounted on the B-17? Something to think about and imagine what a Lancaster would look like with a pair of these things strapped to it.
