{"id":"F2005L02066","name":"AD/CESSNA 650/7 - Actuator Control Unit","slug":"ad-cessna-650-7-actuator-control-unit","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":36260,"registerId":"commonwealth-F2005L02066-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Cessna 650 (Citation III) Series Aeropla","sectionType":"division","heading":"Cessna 650 (Citation III) Series Aeroplanes","content":"### Cessna 650 (Citation III) Series Aeroplanes\n\n| AD/CESSNA 650/7 | Actuator Control Unit | 9/2005 |\n| --------------- | --------------------- | ------ |\n\n```html\n

Applicability:

All Model 650 aeroplanes.

Requirement:

1. Inspect the actuator control unit (ACU) to determine the part number (P/N) in accordance with the Accomplishment Instructions of Cessna Service Bulletin SB 650-27-53, dated 11 March 2004. If an ACU having P/N 9914197-7 is installed on the aeroplane, then no further action is required by this Directive.

2. If an ACU with either P/N 9914197-3 or P/N 9914197-4 is installed on the aeroplane, replace the existing ACU in accordance with SB 650-27-53 with a new, improved ACU having P/N 9914197-7.

Later revisions of the above SB, approved by the United States Federal Aviation Administration (FAA) as an Alternate Method of Compliance (AMOC) to FAA AD 2005-13-21, are considered acceptable for compliance with the equivalent Requirements of this Directive.

3. Revise the Limitations and Normal Procedures sections of the aircraft flight manual (AFM) by inserting into the AFM a copy of all the applicable Cessna temporary revisions (TRs) listed in the following Table:

AFM Revisions

Applicable Model 650 aeroplanes

Cessna TR(s)

Citation III, S/Ns 0001 through 0199 inclusive and 0203 through 0206 inclusive; equipped with Honeywell SPZ-8000 integrated avionics system.

65C3FM TC-R02-01, dated 12 May 2004, and 65C3FM TC-R02-06, dated 11 August 2004.

Citation III, S/Ns 0001 through 0199 inclusive, and 0203 through 0206 inclusive; not equipped with Honeywell SPZ-8000 integrated avionics system.

65C3FM TC-R02-01, dated 12 May 2004, and 65C3FM TC-R02-07, dated 11 August 2004.

Citation VI, S/Ns 0200 through 0202 inclusive, and 0207 and subsequent

65C6FM TC-R04-01, dated 12 May 2004, and 65C6FM TC-R04-06, dated 11 August 2004.

Citation VII, S/Ns 7001 and subsequent

65C7FM TC-R10-01, dated 12 May 2004.

Citation VII, S/Ns 7001 and subsequent, equipped with Honeywell SPZ-8000 integrated avionics system.

65C7FM TC-R10-07, dated 11 August 2004.

Note 1: When a statement identical to that in the applicable TR(s) listed in the above Table has been included in the general revisions of the AFM, the general revisions may be inserted into the AFM, and the copy of the applicable TR may be removed from the AFM.

Note 2: FAA AD 2005-13-21 Amdt 39-14158 refers.

Compliance:

For Requirements 1 and 2 - Within 12 months after the effective date of this Directive.

For Requirement 3 - Within 1 month after the effective date of this Directive or concurrently with the replacement required by Requirement 2, whichever occurs first.

This Airworthiness Directive becomes effective on 1 September 2005.

Background:

This Directive requires the inspection of the ACU to determine the part number and, if necessary, the replacement of the ACU with a new, improved ACU. The Directive also requires the revision of the AFM Limitations Section. These actions are intended to prevent uncommanded movement of the horizontal stabilizer, which could result in reduced controllability of the aeroplane.

\n```\n\n![](image.001.png) \nDavid Villiers \nDelegate of the Civil Aviation Safety Authority\n\n21 July 2005","sortOrder":0},{"sectionNumber":"AD/CESSNA 650/7","sectionType":"part","heading":"AD/CESSNA 650/7","content":"## AD/CESSNA 650/7","sortOrder":1},{"sectionNumber":"Actuator Control Unit","sectionType":"part","heading":"Actuator Control Unit","content":"## Actuator Control Unit","sortOrder":2},{"sectionNumber":"9/2005","sectionType":"part","heading":"9/2005","content":"## 9/2005","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":6,"scope_assessment":{"changed":false,"description":"The directive's scope matches its stated background: it targets all Model 650 aeroplanes and prescribes inspection, conditional replacement of the ACU, and AFM revisions to prevent uncommanded horizontal‑stabiliser movement. The text confines actions to those mechanical and documentation changes and cross-references the FAA AD and Cessna SB without expanding obligations beyond those measures."},"complexity_factors":["Technical specificity of affected parts: three discrete ACU part numbers and a mandatory replacement (Requirements 1–2).","Dependency on an external service document: compliance directed via Cessna Service Bulletin SB 650-27-53 (Requirements 1–2).","AFM amendment complexity: insertion of different temporary revisions (TRs) based on serial number and avionics fit (Requirement 3 and AFM Revisions table).","Regulatory cross-references: acceptance of later SB revisions as FAA AMOC to FAA AD 2005-13-21 (paragraph re: AMOC / Note 2).","Multiple compliance deadlines and sequencing: 12 months for inspection/replacement and 1 month for AFM revision (Compliance).","Recordkeeping and operational burden on operators: AFM changes and part replacement impose administrative and maintenance actions (Requirement 3; Compliance).","Potential supply/logistics risk for obtaining the improved ACU (implied by required replacement within timeframes)."],"plain_english_summary":"This directive applies to all Cessna Model 650 aeroplanes. It requires operators to inspect the actuator control unit (ACU) part number and replace P/N 9914197-3 or -4 with improved P/N 9914197-7 (per Cessna SB 650‑27‑53).\n\nIt also requires inserting specified temporary revisions into the Aircraft Flight Manual. Deadlines: 12 months for inspection/replacement; 1 month for the AFM change. Operators must carry and fund compliance. CASA made it effective 1 September 2005 to prevent uncommanded horizontal‑stabiliser movement."},"kimi_summary":{"content_quality":"ok","complexity_score":4,"scope_assessment":{"changed":false,"description":"This is a standard Airworthiness Directive with a focused, single-purpose scope: addressing a specific defective part in a specific aircraft type. The scope has not expanded beyond its original safety intent."},"complexity_factors":["Multiple conditional requirements based on specific part numbers (9914197-3, 9914197-4 vs 9914197-7)","Cross-referencing to external technical documents: Cessna Service Bulletin SB 650-27-53 and multiple Temporary Revisions (TRs) with specific dates","Model-specific and serial number-specific applicability requiring operators to match their aircraft against five different categories in a table","Nested compliance deadlines with 'whichever occurs first' logic for Requirement 3","Reference to US FAA AD 2005-13-21 and AMOC (Alternate Method of Compliance) provisions for alternative compliance paths","Technical aviation terminology throughout (ACU, AFM, P/N, S/N, TR, AMOC) requiring domain knowledge"],"plain_english_summary":"This CASA Airworthiness Directive mandates inspections and actions for all Cessna 650-series (Citation III/VI/VII) jets to address a defective actuator control unit (ACU) that can cause uncommanded horizontal stabilizer movement and loss of control. Operators must verify ACU part numbers and replace affected units with the improved part, and insert specified temporary revisions into the aircraft flight manual.\n\nCompliance deadlines: AFM update within 1 month of 1 Sep 2005 (or at replacement), and inspection/replacement within 12 months."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-650-7-actuator-control-unit","history":"/api/acts/ad-cessna-650-7-actuator-control-unit/history","analysis":"/api/acts/ad-cessna-650-7-actuator-control-unit/analysis","conflicts":"/api/acts/ad-cessna-650-7-actuator-control-unit/conflicts","importantCases":"/api/acts/ad-cessna-650-7-actuator-control-unit/important-cases","documents":"/api/acts/ad-cessna-650-7-actuator-control-unit/documents"}}