And interestingly, the VC10 in your picture (K MK3 / Super VC10) had a tailfin tank which held 5.5 tonnes of fuel. It too was a place to stuff extra fuel rather than a trim tank. Although later in the VC10s life, fuel management was changed to adjust the C of G. But this was to conserve fatigue life rather than to save a bit of trim darg.
Indeed, and if you've ever climbed through the small panel at the bottom of the fin and wriggled all the way up to the top (as I have done many times), you would have appreciated being at the sharp end even more. Quite tight in there.
Regards!
VC10 Rib22
