Federal Department of the Environment, Transport, Energy and 

Communications DETEC

Federal Office of Civil Aviation FOCA

Safety Division - Aircraft

Lufttüchtigkeitsanweisung (LTA)

Consigne de Navigabilité (CN)

Direttive sulla Navigabilità (DN)

Airworthiness Directive (AD)

FOCA AD

HB-2014-008

Inkraftsetzung

Mise en vigueur

Entrata in vigore

Effective Date

23 December 2014 Pilatus – PC-7

FOCA TC/TCDS No: F 56-20

1/2

Rechtsgrundlage: Art. 26, 51 und 51A (Verordnung über die Lufttüchtigkeit von Luftfahrzeugen: SR 748.215.1)

Base juridique: Art. 26, 51 et 51A (Ordonnance sur la navigabilité des aéronefs: SR 748.215.1)

Base giuridica: Art. 26, 51 e 51A (Ordinanza concernente la navigabilità degli aeromobili: SR 748.215.1)

Legal base: Art. 26, 51 and 51A (Ordinance on the airworthiness of aircraft: SR 748.215.1)

Issue Date: 09 December 2014

ATA Chapter: ATA 21 – Air Conditioning

Subject: Air Conditioning – Compressor Cover Assembly – Installation

Supersedure / Revised

AD(s):

Not applicable

Type Certificate Holder’s Name:

Pilatus Aircraft Ltd.

Manufacturer(s): Pilatus Aircraft Ltd.

Applicability: Model PC-7 aircraft, Manufacturer Serial Numbers (MSN) 101 through 

MSN 607, Pre Service Bulletin 21-006.

Reason: This Airworthiness Directive (AD) is prompted due to an unprotected routing of the oil cooler inlet-hose close to the air conditioning compressor 

clutch plate.

If a spring on the compressor clutch plate shears it could lead to a damage of the oil hose and the engine oil can spill into the engine bay.

In order to correct and control the situation, this AD requires the installation of a cover assembly which will be mounted on the attachment points 

of the compressor.

Required Action(s) 

and Compliance 

Time(s):

Required as indicated below, unless already accomplished:

(1) Within the next 120 days after the effective date of this AD, install a 

cover assembly on the attachment points of the compressor as 

required by paragraph (§) 3.B. of PILATUS PC-7 Service Bulletin 

No. 21-012.

Ref. Publication(s): PILATUS PC-7 Service Bulletin No. 21-012, initial issue.

The use of later approved revisions of this document is acceptable for 

compliance with the requirements of this AD.

For further information 

contact:

The applicable manufacturer’s documentation may be obtained directly 

from:
Lufttüchtigkeitsanweisung (LTA)

Consigne de Navigabilité (CN)

Direttive sulla Navigabilità (DN)

Airworthiness Directive (AD)

FOCA AD

HB-2014-008

2/2

Rechtsgrundlage: Art. 26, 51 und 51A (Verordnung über die Lufttüchtigkeit von Luftfahrzeugen: SR 748.215.1)

Base juridique: Art. 26, 51 et 51A (Ordonnance sur la navigabilité des aéronefs: SR 748.215.1)

Base giuridica: Art. 26, 51 e 51A (Ordinanza concernente la navigabilità degli aeromobili: SR 748.215.1)

Legal base: Art. 26, 51 and 51A (Ordinance on the airworthiness of aircraft: SR 748.215.1)

PILATUS AIRCRAFT LTD.

Customer Technical Support (MCC)

P.O. Box 992

CH-6371 Stans, Switzerland

Tel.: +41 (0)41 619 67 74 Fax: +41 (0)41 619 67 73

E-mail: Techsupport@pilatus-aircraft.com

For further information contact:

FEDERAL OFFICE OF CIVIL AVIATION (FOCA)

Design and Production (STEH)

CH-3003 Bern, Switzerland

E-mail: airdir@bazl.admin.ch