### AIRWORTHINESS DIRECTIVE

No F-2007-027 Distribution:



### A Issue date:

January 02, 2008 Page :

1/3

This Airworthiness Directive is published by the DG AC 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 Airwo rthiness Directive applies, except in accordance with the requirements of that Airworthiness Directive, unless otherwise agreed with the Authority of the St ate 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/Replacem ent

1. EFFECTIVITY :

EUROCOPTER AS332 C, C1, L, L1, L2 and EC225 LP hel icopters, with serial numbers below SN 2680 and helicopters with serial numbers from SN 9000 (i nclusive) to SN 9009 (inclusive), and equipped with tail gear box (TGB) attachment fittings, all part n umbers.

2. REASONS :

This Airworthiness Directive (AD) is issued follow ing the discovery of interference between the end o f the

threaded section of the TGB aft attachment bolt and the structure fitting during a scheduled maintenan ce check (750-hour inspection).

This interference is due to a manufacturing anomal y of the fittings: the blind hole which provides cl earance for the bolt in the structure fitting is missing.

Such interference does not enable correct axial ti ghtening of the TGB casing, even if the torque load applied to the attachment screw, is correct.

Insufficient tightening can cause damage to the TG B attachment and give rise to crack initiation unde r the

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

the loss of the TGB and then involve the risk of lo sing 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 fittin gs,

 if a non-conformity is discovered:

- First of all, replace the attachment bolt(s) if t hey 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 e ffective date of this AD:

3.1. On the TGB aft attachment fitting:

3.1.1. No later than within 50 flying hours, check whethe r the blind hole is present in the TGB aft attachment fitting, in compliance with the instruct ions 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 sec tion 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 pa ragraph 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 l atest by December 31, 2008 (the first limit reached is applicable), return the TGB aft attachme nt 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 whethe r the blind hole is present in the TGB forward attachment fitting, in compliance with the instruct ions specified in paragraph 2.B.4. of the referenced ASB corresponding to the aircraft versio n.

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 sec tion 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 specifi ed 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 la test by December 31, 2008 (the first limit reached is applicable), return the TGB forward atta chment fitting to conformity, in compliance with the instructions specified in parag raph 2.B.5. of the referenced ASB corresponding to the aircraft version.

4. REFERENCE PUBLICATIONS :

EUROCOPTER EC 225 Alert Service Bulletin No. 53A01 2

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:

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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 diffu sion 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 o peration, 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.