{"id":"F2006L03185","name":"AD/RAD/86 - Caledonian Airborne Systems CPT-600/900 Emergency Locator Transmitters","slug":"ad-rad-86-caledonian-airborne-systems-cpt-600-900-emergency-locator-transmitters","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":60486,"registerId":"commonwealth-F2006L03185-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Radio Communication and Navigation Equip","sectionType":"division","heading":"Radio Communication and Navigation Equipment","content":"### Radio Communication and Navigation Equipment\n\n| AD/RAD/86 | Caledonian Airborne Systems CPT-600/900 Emergency Locator Transmitters | 11/2006 |\n| --------- | ---------------------------------------------------------------------- | ------- |\n\n```html\n

Applicability:

Caledonian Airborne Systems CPT-600 and CPT-900 Automatic Deployable Emergency Locator Transmitter (ADELT) and Automatic Deployable/Automatic Fixed Emergency Locator Transmitter (AD/AFELT).

Note 1: CPT-600 and CPT-900, ADELT and AD/AFELT systems are known to be installed on, but not limited to, the following aircraft:

Manufacturer

Aircraft Model

Bell Helicopter Textron
EADS
Eurocopter
Sikorsky

212 and 214 series
ATR-42
AS 332, AS 365 N and BO 105
S-61 and S-76

Note 2: CPT-600 and CPT-900, ADELT and AD/AFELT systems are also known to be installed on the following military aircraft:

Manufacturer

Aircraft Model

Eurocopter
Sikorsky

AS 352, AS 565 and AS 321
S-70A

Requirement:

Modify the affected CPT-600/-900 ADELT and AD/AFELT Systems by replacing the main case part number (P/N) BC85-051 and piston P/N BC85-052 with improved units made of stainless steel 6S80D in accordance with Caledonian Airborne Systems Service Bulletin No.CPT-600/900/SB-01 Issue 1 dated February 2006 or later EASA approved revision.

Note 3: EASA AD 2006-0241 refers.

Compliance:

Within six months after the effective date of this Directive.

This Airworthiness Directive becomes effective on 26 October 2006.

\n```\n\n| Background: | The manufacturer has received a report that during a maintenance activity a beacon failed to deploy, highlighting wear in the main case P/N BC85-051 and profiling of the piston P/N BC85-052 which is prone to cupping seizures. Original main cases P/N BC85-051 up to S/N 311 were manufactured from stainless steel AISI 303. In May 1990 the material specification changed to stainless steel 6S80D that has three times the hardness.The wear highlighted was on an original main case P/N BC85-051 and took the form of “cupping” around the locking sphere holes that prevented the separation of the sleeve retainer from the main case. Original Pistons P/N BC85-052 up to S/N 299 were manufactured prior to 1990 and their sphere contact profile is more prone to cupping seizures.After investigation by Caledonian Airborne Systems they advise that original main cases and pistons, which are now in excess of 15 years age, be removed from service. |\n| ----------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |\n\n![](image.001.png) \nJames Coyne \nDelegate of the Civil Aviation Safety Authority\n\n13 September 2006","sortOrder":0},{"sectionNumber":"AD/RAD/86","sectionType":"part","heading":"AD/RAD/86","content":"## AD/RAD/86","sortOrder":1},{"sectionNumber":"Caledonian Airborne Systems CPT-600/900 ","sectionType":"part","heading":"Caledonian Airborne Systems CPT-600/900 Emergency Locator Transmitters","content":"## Caledonian Airborne Systems CPT-600/900 Emergency Locator Transmitters","sortOrder":2},{"sectionNumber":"11/2006","sectionType":"part","heading":"11/2006","content":"## 11/2006","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The Directive implements the manufacturer's corrective measure to remove original BC85-051/BC85-052 units and replace them with 6S80D parts (Requirement; Background). It does not expand applicability beyond CPT-600/900 ADELT and AD/AFELT installations listed, but it converts the manufacturer recommendation into an enforceable regulatory requirement with a six-month compliance deadline and references the related EASA AD (Compliance; Note 3)."},"complexity_factors":["Identification of affected hardware by part numbers (BC85-051, BC85-052) and serial-number history (original units up to S/N 311 and S/N 299 respectively) (Background).","Dependency on Caledonian Service Bulletin CPT-600/900/SB-01 or a later EASA-approved revision (Requirement; Note 3).","Sourcing and installing replacement stainless-steel 6S80D units (logistics, spare parts availability).","Single corrective action with a fixed six-month compliance window, creating scheduling and maintenance downtime pressure (Compliance).","Applicability across multiple civil and military aircraft types, increasing coordination across operators and maintainers (Applicability/Notes).","Regulatory cross-reference to EASA AD 2006-0241, requiring alignment with overseas certification actions (Note 3)."],"plain_english_summary":"This Airworthiness Directive requires replacing the main case (P/N BC85-051) and piston (P/N BC85-052) in Caledonian CPT-600 and CPT-900 automatic deployable/automatic fixed emergency locator transmitters with stainless-steel 6S80D units, in accordance with Caledonian Service Bulletin CPT-600/900/SB-01 or a later EASA-approved revision. It applies to aircraft fitted with these beacons and must be done within six months of the Directive’s effective date (26 October 2006). The change addresses wear and “cupping” seizures that can prevent beacon deployment."},"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a standard Airworthiness Directive with a narrow, targeted scope addressing a specific safety defect in particular emergency locator transmitter models. The scope remains precisely limited to the identified technical issue and affected aircraft."},"complexity_factors":["Single, specific technical requirement with clear part numbers and replacement specifications","Limited applicability to specific aircraft models and beacon types (CPT-600/900 series)","Straightforward compliance deadline (6 months from effective date)","References external technical document (Service Bulletin) but provides specific part numbers for identification","Contains technical aviation terminology (ADELT, AD/AFELT, part numbers, material specifications) but in a structured table format","No nested exceptions, conditional logic, or extensive cross-referencing to other legislation"],"plain_english_summary":"This AD mandates replacing worn aluminium main cases and pistons in Caledonian CPT‑600 and CPT‑900 emergency locator transmitters with improved stainless‑steel parts because wear can cause “cupping seizures” that prevent beacon deployment in a crash. It affects owners/operators of aircraft fitted with these models (civil and military types listed in the full text) and requires compliance with Caledonian Service Bulletin CPT‑600/900/SB‑01 (or later EASA‑approved version) within six months of 26 Oct 2006; non‑compliance is unlawful."}},"importantCases":[],"_links":{"self":"/api/acts/ad-rad-86-caledonian-airborne-systems-cpt-600-900-emergency-locator-transmitters","history":"/api/acts/ad-rad-86-caledonian-airborne-systems-cpt-600-900-emergency-locator-transmitters/history","analysis":"/api/acts/ad-rad-86-caledonian-airborne-systems-cpt-600-900-emergency-locator-transmitters/analysis","conflicts":"/api/acts/ad-rad-86-caledonian-airborne-systems-cpt-600-900-emergency-locator-transmitters/conflicts","importantCases":"/api/acts/ad-rad-86-caledonian-airborne-systems-cpt-600-900-emergency-locator-transmitters/important-cases","documents":"/api/acts/ad-rad-86-caledonian-airborne-systems-cpt-600-900-emergency-locator-transmitters/documents"}}