EASA AD No.: 2015-0099

TE.CAP.00110-004 © European Aviation Safety Agency. All rights reserved. 1/2 

Proprietary document. Copies are not controlled. Confirm revision status through the EASA-Internet/Intranet.

EASA AIRWORTHINESS DIRECTIVE 

AD No.: 2015-0099 

Date: 03 June 2015 

Note: This Airworthiness Directive (AD) is issued by EASA, acting in accordance with Regulation 

(EC) No 216/2008 on behalf of the European Community, its Member States and of the 

European third countries that participate in the activities of EASA under Article 66 of that 

Regulation.

This AD is issued in accordance with EU 748/2012, Part 21.A.3B. In accordance with EU 1321/2014 Annex I, Part M.A.301, the 

continuing airworthiness of an aircraft shall be ensured by accomplishing any applicable ADs. Consequently, no person may operate an 

aircraft to which an AD applies, except in accordance with the requirements of that AD, unless otherwise specified by the Agency [EU 

1321/2014 Annex I, Part M.A.303] or agreed with the Authority of the State of Registry [EC 216/2008, Article 14(4) exemption]. 

Design Approval Holder’s Name: 

BAE SYSTEMS (OPERATIONS) Ltd 

Type/Model designation(s): 

Jetstream 4100 aeroplanes

TCDS Number: EASA.A.189 

Foreign AD: Not applicable 

Supersedure: None 

ATA 27 Flight Controls – Elevator Trim Circuit – Inspection / Modification 

Manufacturer(s): British Aerospace plc, British Aerospace (Commercial Aircraft) Ltd, British 

Aerospace Regional Aircraft Ltd, Jetstream Aircraft Ltd and British Aerospace 

(Operations) Ltd. 

Applicability: Jetstream 4100 aeroplanes, all models, all serial numbers. 

Reason: An in-service event was reported of the Pitch Trim jammed in the fully down 

position. During the event, the trim circuit was adjusted fully nose down and the 

swaged stop on the trim cable passed beyond the stop plates. With gear down 

and the autopilot disconnected, the aeroplane pitched nose down and, even 

with the control column pulled fully back, the pilot was unable to prevent 

descent. The trim circuit was freed and control restored by the combined efforts 

of both pilots turning the trim handwheels, which forced the swaged stop on the 

trim cable back past the broken stop plates. The results of the technical 

investigation revealed that the pitch trim servo motor travel stops were 

incorrectly adjusted, allowing the servo motor to force contact of the swaged 

stop on the trim cable with the stop plates, and parts of the stop plates breaking 

off. 

This condition, if not detected and corrected, could lead to loss of control of the 

elevator trim, possibly resulting in reduced control of the aeroplane. 

To address this unsafe condition, BAE Systems (Operations) Ltd issued 

Inspection Service Bulletin (ISB) 27-068 to provide instructions to inspect and 

correct pitch trim servo motor travel stop adjustment and to install new stop 

plates made of improved (more robust) material. 

For the reasons described above, this AD requires a one-time inspection to 
EASA AD No.: 2015-0099

TE.CAP.00110-004 © European Aviation Safety Agency. All rights reserved. 2/2 

Proprietary document. Copies are not controlled. Confirm revision status through the EASA-Internet/Intranet.

correct adjustment of the pitch trim servo motor travel stops to prevent the jam 

condition and, if damage is found, replacement of the stop arms and plates. 

Effective Date: 17 June 2015 

Required Action(s) 

and Compliance 

Time(s): 

Required as indicated, unless accomplished previously: 

(1) Within 30 days after the effective date of this AD accomplish a one-time 

inspection of the pitch trim travel stops in accordance with the instructions 

of BAE Systems (Operations) Ltd SB J41-27-068. 

(2) If, during the inspection as required by paragraph (1) of this AD, any 

damage is found to the stop arms, before next flight, replace the stop arms 

and install new stop plates in accordance with the instructions of the BAE 

Systems (Operations) Ltd SB J41-27-068. 

Ref. Publications: BAE Systems (Operations) Ltd, ISB J41-27-068 original issue dated 21 January 

2014. 

The use of later approved revisions of these documents is acceptable for 

compliance with the requirements of this AD. 

Remarks: 1. If requested and appropriately substantiated, EASA can approve 

Alternative Methods of Compliance for this AD. 

2. This AD was posted on 29 April 2015 as PAD 15-055 for consultation until 

27 May 2015. No comments were received during the consultation period. 

3. Enquiries regarding this AD should be referred to the Safety Information 

Section, Certification Directorate, EASA. E-mail: ADs@easa.europa.eu. 

4. For any question concerning the technical content of the requirements in 

this AD, please contact: 

BAE Systems (Operations) Ltd, Customer Information Department, 

Prestwick International Airport, Ayrshire, KA9 2RW, Scotland, United 

Kingdom; Telephone +44 1292 675207, Facsimile +44 1292 675704; 

E-mail: RApublications@baesystems.com.