EASA AD CF-2021-45
Navigation — Radio Altimeter Coaxial Cable Damaged
Summary
Canadian Airworthiness Directive CF-2021-45 addresses a safety issue affecting Bombardier Inc. model BD-700-2A12 aeroplanes, serial numbers 70006 through 70053. The directive mandates inspection and replacement of damaged radio altimeter coaxial cables to prevent erroneous altitude data during flight. This AD aims to ensure reliable terrain awareness warning system performance by correcting cable routing and condition.
What Changed
CF-2021-45 introduces a new requirement for the replacement and re-routing of radio altimeter coaxial cables in affected Bombardier BD-700-2A12 aircraft. It specifies compliance with Bombardier Service Bulletin 700-91-7502 Revision 1 or earlier approved revisions. This directive is a new regulation addressing previously identified cable damage issues.
Why It Matters
This directive is critical for aviation professionals because damaged coaxial cables can cause loss or degradation of radio altimeter signals, potentially leading to unannounced loss of terrain awareness warnings during approach. Operators and maintenance teams must ensure compliance to maintain flight safety and regulatory conformity. Failure to comply could compromise aircraft safety and regulatory approval for takeoff.
What To Do
Operators of Bombardier BD-700-2A12 aircraft with serial numbers 70006 through 70053 must replace and re-route the affected radio altimeter coaxial cables within 12 months of the effective date, which is 21 December 2021. Compliance can be achieved by following the instructions in Bombardier Service Bulletin 700-91-7502 Revision 1 or the original issue dated 6 February 2020. Contact Transport Canada for any alternative means of compliance if necessary.
AI-generated summary from official EASA source document. Always verify against the original.