Whilst a number of responses have said that the revalidation (by experience) endorsement must be made prior to expiry, I can't find anything on the CAA website that states that. Neither can I find any reference to it in an old version of LASORS. Can anybody point me to a relevant clause in anything official?
Although I cannot find the specific wording you seek, the following quote from Part.FCL makes it clear that, once expired, Class and Type Ratings cannot be 'Revalidated' but must be 'Renewed'.
FCL.740 Validity and renewal of class and type ratings
(a) The period of validity of class and type ratings shall be 1 year, except for singlepilot single-engine class ratings, for which the period of validity shall be 2 years, unless otherwise determined by the operational suitability data, established in accordance with Part-21
(b) Renewal. If a class or type rating has expired, the applicant shall:
(1) take refresher training at an ATO, when necessary to reach the level of
proficiency necessary to safely operate the relevant class or type of
aeroplane; and
(2) pass a proficiency check in accordance with Appendix 9 to Part-FCL.
MJ
