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How does an Aircraft make journey from a Type certificate (TC) to Certificate of Airworthiness (C of A) ? What is the need of STC ?
✔Certification is a regulatory obligation for all aircrafts, their engines & propellers.
✔Introduced by one of the UK’s first Secretary of State for Air-Winston Churchill ,Type Certificate (TC) is issued to signify the airworthiness of an aircraft manufacturing design prior production.
✔Certificate of Airworthiness (C of A) is issued by the National Aviation Authority (NAA) to certify that an aircraft is fit for flying post production.
✔A stringent certification process goes through the complete development process of a new aircraft.
Broad phases are:
👉 Application(TC) & Detailed design review,amendments.
👉Test review, participation in laboratory & production.
👉Post production test review & participation in flight (for mods in lieu of the results).
👉Aircraft operators (service introduction).
✔Major aircraft certification systems globally are:
👉For the United States, FAR 25 regulations.
👉For the European Union, JAR 25 regulations.
✔Supplemental type certificate (STC) is needed in case of major modification or repair to an existing type certified aircraft, engine or propeller.
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Author – Tanmay Palei
Sr. Aircraft Structure Engineer