Airworthiness and Certification
The Certificate of Airworthiness
Airworthiness is governed by Annex 8 and the associated Brunei requirements. A Certificate of Airworthiness (C of A) is issued when the aircraft type holds a Type Certificate and the individual aircraft conforms to that type design and is in a condition for safe operation. The C of A has a validity period and is maintained through continuing airworthiness: inspections, maintenance programmes, airworthiness directives (ADs), service bulletins, and defect reporting. The Certificate of Registration is not evidence of airworthiness; the C of A is.
Continuing Airworthiness
Key concepts: the approved maintenance organisation, the maintenance control manual, the aircraft technical log, and the release to service. Airworthiness Directives are mandatory; service bulletins are generally not unless incorporated by an AD or by the operator's programme. Modifications and repairs require approval. A permit to fly may be issued for specific non-standard flights (ferry, test, exhibition) where a C of A cannot be issued.
Traps and Rule of Thumb
Traps: treating an expired C of A as valid because maintenance is current; assuming a foreign C of A is automatically accepted (validation or acceptance is required); confusing a Type Certificate (design) with a C of A (individual aircraft); and forgetting that defect reporting and AD compliance are continuing obligations, not one-off events.
Worked example: An AD is issued with an effective date next month. The aircraft may continue flying until that date, but not beyond it without compliance - the AD is mandatory from its effective date regardless of the next scheduled inspection.