Westland WG.33
(A what if, or possibly an April Fool's scenario)
"Suicide Bubble" might be an apt name for this, or maybe the "Fort Zinderneuf Helo" after the Beau Geste fort where everyone got killed when they got ordered up the observation tower. This little thing was an observation prototype that never got off the ground but you are well within your rights to assume that Westland Helicopters made one or two without any official requirements and shipped them off to Europe before someone at the MoD realised what was going on and made them stop.
The WG.33 had a circular body giving excellent vision.
Rotor diameter: 5.0m, fuselage length: 2.0m, max take-off weight: 500kg, max speed: 157km/h, cruising speed: 130km/h.
It has as much armour as a sturdy shower curtain.
