AIRWORTHINESS DIRECTIVE
On the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/CESSNA 150/31 Amdt 3 and issues the following 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 150, F150, 152 & F152 Series Aeroplanes
AD/CESSNA 150/31 Amdt 4
Vertical Fin Attach Brackets,
Nutplates and Fittings
11/2006
 
Applicability:
All Models 150, A150, F150, FA150 and FRA150 aircraft.
Model 152 aircraft, with serial numbers 15279406 through 15284541.
Model A152 aircraft, with serial numbers A1520735 through A1520943.
Model F152 aircraft with serial numbers F15201429 through F15201808.
Model FA152 aircraft with serial numbers FA1520337 through FA1520372.
Model FRA150L and FRA150M aircraft, with serial numbers FRA1500121 through FRA1500336.

Requirement:
1.    Inspect the attach bracket and nutplates using the method detailed in Cessna SIL No. SE 79-49 Revision 1, or Reims Aviation Service Bulletin No. 24 Revision 1, as applicable.
2.    a.     Remove paint from both base radii on each of the port and starboard rear attach fittings.
b.    Visually check the radius area, inspecting for cracking and/or corrosion.  If there are indications of either condition the brackets are to be replaced.
c.     Re-protect the subject area with an approved protective treatment.
Note1:  FAA AD 80-11-04 and EASA AD 2006-0267 refer.
Note 2:  The inspection requirements of this Directive are no longer required if the part number NAS 1068A4 nutplates are replaced with AN365-428, MS20365-428, MS21042L4, or MS21044N4 nuts.

Compliance:
For FRA150L and FRA150M aircraft, inspect within 100 hours time in service after 26 October 2006, and thereafter at intervals not exceeding 100 hours time in service until the affected nutplates are replaced (See Requirement Note 2).

 
 
 
For all other aircraft, inspect within 100 hours time in service after 31 November 1984, and thereafter at intervals not exceeding 100 hours time in service until the affected nutplates are replaced (See Requirement Note 2).  The compliance time for these aircraft is unchanged.

 
This Amendment becomes effective on 26 October 2006.

Background:
Cracked vertical fin attachment nutplates have been found on in-service aircraft.  Undetected cracking could result in structural failure and consequent separation of the vertical or vertical and horizontal tail assembly from the aircraft.
Amendment 3 corrected aircraft applicability so as to only include aircraft fitted with the fabricated attach bracket.
Amendment 4 is issued to introduce optional terminating action to the inspection requirements of this Directive, as specified in EASA AD 2006-0267 and FAA AD 80-11-04; and to include Models FRA150L and FRA150M aircraft.

David Villiers
Delegate of the Civil Aviation Safety Authority
14 September 2006