PART 10Prohibited behaviour, directives, rules, powers and penalties
CHAPTER 4Powers and penalties
Certificates, authorisations, approvals and permissions269
Wherever in this Order there is provision for the issue or grant of a certificate, authorisation, approval or permission by the CAA, unless otherwise provided, such a certificate, authorisation, approval or permission—
a
must be in writing;
b
may be issued or granted subject to such conditions as the CAA thinks fit; and
c
may be issued or granted, subject to article 253, for such periods as the CAA thinks fit.