A question arising from another thread :
UK AIP ENR 1-2-1 extract -
2. Special VFR Flight
2.1 Clearance for Special VFR flight in the UK is an authorization by ATC for a pilot to fly within a Control Zone although he is unable to comply with IFR. In exceptional circumstances, requests for Special VFR flight may be granted for aircraft with an all-up-weight exceeding 5700 kg and capable of flight under IFR.
So what exceptional circumstances apply that allow a fully rated airline crew in their +5700kgs airliner to fly night circuits in a CTR at night with a SVFR clearance ?