Derick,
I doubt the VC10 VVIP Operation would work in the age of Haddan Cave or the risk assessed world of Civ air in 2015!
In effect the Captain was making the risk assessment on the VVIP often outside of the VC 10 go/no go list.
IMHO some of the most risky flying the VC10 ever did, unknown to the VIP down the back.