AIRWORTHINESS DIRECTIVE 

No F-2007-027 

Distribution: 

A 

Issue date: 

January 02, 2008 

 

Page : 

1/3 

This Airworthiness Directive is published by the DGAC as the 

Airworthiness Authority of the State of production for the affected aircraft.

 

Translation of « Consigne de Navigabilité » of same

number. 

In case of difficulty, reference should be made to 

the French issue.

Direction 

générale 

de 

l’aviation

civile 

France 

GSAC 

publication

No person may operate an aircraft to which an Airworthiness Directive applies, 

except in accordance with the requirements of that Airworthiness Directive, 

unless otherwise agreed with the Authority of the State of Registry.

Corresponding foreign Airworthiness Directive(s): 

Not applicable 

Airworthiness Directive(s) replaced: 

UF-2007-027 

Person in charge of airworthiness:

EUROCOPTER 

Type certificate(s) No. EASA.R.002

TCDS No EASA.R.002

Type(s): 

AS 332 series and EC 225 LP helicopters 

ATA chapter: 

53 

Subject: 

Fuselage - TGB attachment fittings - Check/Replacement 

1. EFFECTIVITY: 

 EUROCOPTER AS332 C, C1, L, L1, L2 and EC225 LP helicopters, with serial numbers below SN 2680 

and helicopters with serial numbers from SN 9000 (inclusive) to SN 9009 (inclusive), and equipped with

tail gear box (TGB) attachment fittings, all part numbers. 

2. REASONS: 

 This Airworthiness Directive (AD) is issued following the discovery of interference between the end of the 

threaded section of the TGB aft attachment bolt and the structure fitting during a scheduled maintenance 

check (750-hour inspection). 

 This interference is due to a manufacturing anomaly of the fittings: the blind hole which provides clearance 

for the bolt in the structure fitting is missing. 

 Such interference does not enable correct axial tightening of the TGB casing, even if the torque load

applied to the attachment screw, is correct. 

 Insufficient tightening can cause damage to the TGB attachment and give rise to crack initiation under the 

head of the attachment bolt before the end of the TBO of the TGB is reached. A crack can finally lead to 

the loss of the TGB and then involve the risk of losing the helicopter during the take-off and landing

phases. 

 Consequently, the purpose of this AD is to require on the helicopters in service that are concerned: 

 to check the TGB aft and forward attachment fittings, 

 if a non-conformity is discovered: 

- First of all, replace the attachment bolt(s) if they are damaged, install an additional washer and 

torque-tighten to the recommended torque load, 

- then replace any non-compliant fitting(s). 

n/CG 
AIRWORTHINESS DIRECTIVE 

No F-2007-027 

Distribution: 

A 

Issue date: 

January 02, 2008

Page: 

2/3 

3. MANDATORY ACTIONS AND COMPLIANCE TIMES: 

 The following measures are mandatory as from the effective date of this AD: 

3.1. On the TGB aft attachment fitting: 

3.1.1. No later than within 50 flying hours, check whether the blind hole is present in the TGB aft 

attachment fitting, in compliance with the instructions specified in paragraph 2.B.2. of 

EUROCOPTER AS 332 ASB No. 53.01.58 or EC 225 ASB No. 53A012, referenced below. 

3.1.2. Interpretation of the results: 

a) If the measurement is equal to or greater than 81 mm (blind hole present): 

 Leave as is and resume flights, in compliance with the instructions specified in paragraph 

2.B.2.a. of the referenced ASB corresponding to the aircraft version. 

b) If the measurement is less than 81 mm (blind hole missing): 

 Check the condition of the end of the threaded section of the bolt. Scrap and replace the 

bolt if necessary (sign of chafing, contact mark), then fit the bolt with an additional washer, 

in compliance with the instructions specified in paragraph 2.B.2.b. of the referenced ASB 

corresponding to the aircraft version, then: 

c) No later than within 825 flying hours and at the latest by December 31, 2008 (the first limit 

reached is applicable), return the TGB aft attachment fitting to conformity, in compliance 

with the instructions specified in paragraph 2.B.3. of the referenced ASB corresponding to 

the aircraft version. 

3.2. On the TGB forward attachment fitting: 

3.2.1. No later than within 50 flying hours, check whether the blind hole is present in the TGB forward 

attachment fitting, in compliance with the instructions specified in paragraph 2.B.4. of the 

referenced ASB corresponding to the aircraft version. 

3.2.2. Interpretation of the results: 

a) If both measurements are equal to or greater than 81 mm (blind hole present): 

 Leave as is and resume flights, in compliance with the instructions specified in paragraph 

2.B.4.a. of the referenced ASB corresponding to the aircraft version. 

b) If one or both measurements is/are less than 81 mm (blind hole missing): 

 Check the condition of the end of the threaded section of the bolt(s). Scrap and replace the 

bolt(s) if necessary (sign of chafing, contact mark), then fit the bolt(s)- with an additional 

washer, in compliance with the instructions specified in paragraph 2.B.4.b. of the referenced 

ASB corresponding to the aircraft version, then: 

c) No later than within 825 flying hours and at the latest by December 31, 2008 (the first limit 

reached is applicable), return the TGB forward attachment fitting to conformity, in 

compliance with the instructions specified in paragraph 2.B.5. of the referenced ASB 

corresponding to the aircraft version. 

4. REFERENCE PUBLICATIONS: 

 EUROCOPTER EC 225 Alert Service Bulletin No. 53A012 

 EUROCOPTER AS 332 Alert Service Bulletin No. 53.01.58 

 (or any subsequent approved Revision). 
AIRWORTHINESS DIRECTIVE 

No F-2007-027 

Distribution: 

A 

Issue date: 

January 02, 2008

Page: 

3/3 

5. EFFECTIVE DATE: 

 Upon receipt of the emergency AD from December 07, 2007. 

6. REMARKS: 

6.1. This AD has been the subject of an Emergency diffusion on December 07, 2007 

6.2. For questions concerning the technical contents of this AD’s requirements, contact: 

 EUROCOPTER (STXI) - Aéroport de Marseille Provence 13725 Marignane Cedex - France 

Tél.: 33 (0) 4 42 85 97 97 - Fax: 33 (0) 4 42 85 99 66 

 E.mail: Directive.technical-support@eurocopter.com

7. APPROVAL: 

 This AD is approved by the French DGAC. 

 This AD having for origin a defective production operation, it does not comply with the current EASA 

scope of responsibility. It is up to each national Authority to decide to take into account this AD by the 

statutory means, judged appropriate.