Exemption for aircraft operations of an exceptional nature9
The competent authority for a relevant airport may, in individual cases, authorise a marginally compliant aircraft to land at and take off from that airport, as part of an individual operation, where operating restrictions have been introduced by that authority under these Regulations which would otherwise preclude it, if it appears to him that—
a
the individual operation is of such an exceptional nature that it would be unreasonable to withhold a temporary exemption under this regulation; or
b
the aircraft operation is a non-revenue flight for the purpose of alteration, repair or maintenance.