AD/Cessna 170/78 Flexible Fuel Hose End Fittings (Cth)

AIRWORTHINESS DIRECTIVE

For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.001(1) of CASR 1998.  The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.

Cessna 170, 172, F172, FR172 and 175 Series Aeroplanes

AD/CESSNA 170/78 Flexible Fuel Hose End Fittings 11/2006 DM

Applicability:

Group 1 - Cessna Aircraft not equipped with the Garmin G1000 System:

a.     Model 172R Serial Numbers 17281244 through 17281334; and

b.    Model 172S Serial Numbers 172S9809 through 172S10219 inclusive.

Group 2 - Cessna Aircraft equipped with the Garmin G1000 System:

a.     Model 172R Serial Numbers 17281244 through 17281334; and

b.    Model 172S Serial Numbers 172S9809 through 172S10219 inclusive.

Requirement:

Group 1 - Cessna 172 Aircraft - NOT equipped with the Garmin G1000 System

1.    Inspect the two end fittings on each of the following hoses in the engine compartment for the correct torque values in accordance with Cessna Service Bulletin No SB06-71-02 dated 19 June 2006 or later FAA approved revisions:

i.      Fuel strainer to engine fuel pump.

ii.     Engine fuel pump to fuel injector servo.

iii.    Fuel injector servo to fuel manifold valve (except turbo models).

iv.    Turbo models only: Fuel injector servo to fuel flow transducer.

v.     Turbo models only: Fuel flow transducer to fuel manifold valve.

vi.    Fuel injector servo return to firewall fitting.

2.    If any incorrect torque values are found during the inspection in accordance with Requirement 1 of this AD, clean and dry the threads of all fittings, and tighten the hose end fittings to the correct torque values in accordance with Cessna Service Bulletin No SB06-71-02 dated 19 June 2006 or later FAA approved revisions.

Group 2 - Cessna 172 Aircraft - Equipped with the Garmin G1000 System

3.    Inspect the two end fittings on each of the following hoses in the engine compartment for the correct torque values in accordance with Cessna Service Bulletin No SB06-71-02 dated 19 June 2006 or later FAA approved revisions:

i.      Fuel strainer to engine fuel pump.

ii.     Engine fuel pump to fuel injector servo.

iii.    Fuel injector servo to fuel flow transducer.

iv.    Fuel flow transducer to fuel manifold valve.

v.     Fuel injector servo return to firewall fitting.

4.    If any incorrect torque values are found during the inspection in accordance with Requirement 3 of this AD, clean and dry the threads of all fittings, and tighten the hose end fittings to the correct torque values in accordance with Cessna Service Bulletin No SB06-71-02 dated 19 June 2006 or later FAA approved revisions.

Note:  FAA Airworthiness Directive 2006-17-04 Amendment 39-14725 dated
18 August 2006 refers.

Compliance:

1.    Unless already accomplished, within the next 5 hours time in service after the effective date of this AD.

2.    Before further flight.

3.    Unless already accomplished, within the next 5 hours time in service after the effective date of this AD.

4.    Before further flight.

This Airworthiness Directive becomes effective on 4 September 2006.

Background:

This AD is the result of one report of loose fuel hose connections to the fuel injector servo on a Cessna Model 172S aircraft.  The intent of this AD is to detect and correct any incorrect torque values of the end fittings of flexible fuel hoses in the engine compartment, which could result in the loss of fuel flow and fuel leakage.

Loss of fuel flow could result in partial or complete loss of engine power and fuel leakage could result in an engine compartment fire.

James Coyne
Delegate of the Civil Aviation Safety Authority

24 August 2006