Type Approval Holders Name: BAE SYSTEMS (OPERATIONS) LTD

Type/Model Designation(s): JETSTREAM 4100

Type Certificate Data Sheet No: BA27

Superseded/ Revised ADs: None

Manufacturer(s): Jetstream Aircraft Ltd, British Aerospace Regional Aircraft Ltd, British Aerospace (Commercial Aircraft) Ltd, British Aerospace (Operations) Ltd.

Applicability: All Model Jetstream Series 4100 aeroplanes.

Reason: An operator of a Jetstream 4100 aeroplane suffered a total electrical failure just as the aircraft landed.

Investigations were unable to determine all of the mechanisms for the total failure, however, it was established that a chafe of the exciter wire to the positive terminal of the starter-generator was a significant contributory factor to the incident.

 The current routing of the small wiring at the starter-generator terminal block has the potential for incorrect routing and possible chafing damage. As the starter-generator is removed for overhaul at 600-hour intervals the potential exists for damage and/or mis-routing of wires during removal and re-installation. This AD requires the modification of the aircraft wiring to reduce the likelihood of total electrical failure.

Effective Date: 8 February 2005

Compliance/Action: Required at the next scheduled starter generator change or within six months, whichever occurs later, after the effective date of this AD, carry out the modification of the starter-generator terminal block wiring in accordance with BAE Systems Service Bulletin J41-24-041 Original Issue or later EASA approved revision.

Reference Publications: BAE Systems (Operations) Service Bulletin J41-24-041 at Original Issue, may be obtained from Project Management Group, Customer Information Department, BAE Systems (Operations) Limited, Prestwick International Airport, Ayrshire, KA9 2RW, Scotland. Phone: +44 (0) 1292 675207 Fax: +44 (0)1292 675704 E-mail: Rapublications@baesystems.com

Remarks: Enquiries regarding this Airworthiness Directive should be referred to Civil Aviation Authority, Safety Regulation Group, Certification and Approvals Department, Aviation House, Gatwick Airport South, West Sussex, RH6 0YR, United Kingdom. Phone: +44 (0) 1293 573315 Fax: +44 (0) 1293 573976 email: department.certification@srg.caa.co.uk

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