Sir Niall Dementia,
even considering you meant Night VFR, your statement that sight of the ground is mandatory is still wrong.
SERA.5005(c)(3) only mandates sight of the ground when the aircraft is below 3000 ft AMSL or 1000 ft above terrain, whichever is higher.
Originally Posted by SERA.5005
c) When so prescribed by the competent authority, VFR flights at night may be permitted under the following conditions:
...(iii)in airspace classes B, C, D, E, F and G, at and below 900 m (3 000 ft) AMSL or 300 m (1 000 ft) above terrain, whichever is the higher, the pilot shall maintain continuous sight of the surface; and’;
So you can be VMC at night and have to control your airplane by sole reference to the instruments.
A consequence of that is that you must be above 3000 ft AMSL for flying at night in conditions where the sight of the surface is impossible.