Commonwealth legislation

AD/F100/5 - Powerplant - Lower Cowl Door Engagement

In ForceCTH

Jurisdiction

Commonwealth

Collection

legislative instrument

Plain English Summary

5/10 complexity

This Airworthiness Directive requires operators of specified Fokker F28/F100 serial numbers to inspect and, where needed, modify the lower engine cowl door hook-and-latch assemblies and the mid-clevis fitting following Fokker service bulletin instructions. Compliance is measured in flight cycles (typically within 2,500) or must occur immediately if a cowl mismatch is found. The measure addresses an aerodynamic gap that can prevent hooks from engaging; operators (aircraft owners) pay for inspections, repairs and parts and must record compliance.

JSON API

Deep dive

Want the full deep dive?

Zoe can write the in-depth analysis on top of the summary above: how it works, who it affects and what each part actually does.

Current sections

Direct links to the current provisions in AD/F100/5 - Powerplant - Lower Cowl Door Engagement.

AD/F100/5 - Powerplant - Lower Cowl Door Engagement

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY

SCHEDULE OF AIRWORTHINESS DIRECTIVES

View image in the official source
Fokker F100 (F28 Mk 100) Series Aeroplanes

AD/F100/5 Powerplant - Lower Cowl Door Engagement 1/99

Applicability: Fokker F28-100 and F28-70 series aircraft, serial numbers 11244 through 11469, 11471, 11474 through 11483, 11489, 11490, 11491, 11494, 11498, 11499, 11501,

11502, 11504, 11506, 11507, 11512 through 11515, 11517, 11520, 11528, and

Requirement: 1. Modify the hook and latch assembly of the lower cowl doors in accordance with the instructions in Part 1 of the Accomplishment Instructions of Fokker Service Bulletin SB F100-71-019 dated 21 March 1996.

Note: The accomplishment of Part 1 of Fokker SB F100-71-003, dated 14 April 1989, or Revision 1 dated 08 August 1989, or Revision 2 dated 21 November 1994 is considered an acceptable means of compliance for this requirement.

2. Inspect both engine’s lower cowling door hook and latch assemblies in accordance with Part 2 of the Accomplishment Instructions of Fokker SB F100-71-019 dated 21 March 1996.

3. Modify the lower cowl door’s mid clevis fitting in accordance with the Accomplishment Instructions of Fokker SB P41230-71-07 dated 15 February 1996.

Note: RLD Airworthiness Directive 1989-049/3 (A) dated 28 June 1996 refers.

Compliance: 1. Unless already accomplished, on a limited number of aircraft as applicable, within 2500 flight cycles of the last inspection performed in accordance with BLA 89- 049/2.

2. Within 2500 flight cycles since new or since last inspection in accordance with BLA 89-049/2 as applicable.

3. Following the discovery of a cowl mismatch during accomplishment of Requirement 2. above.

This Airworthiness Directive becomes effective on 28 January 1999.

Background: Experience has shown that an aerodynamic gap/mismatch may exist between the fixed engine cowl and the lower cowl door. Should this mismatch exceed a certain value, one or more hooks may not engage properly. This degrades the redundancy of the lower cowl door engagement in the closed position and could lead to an unsafe condition. This Directive introduces a one time inspection and corrective action if necessary, to measure the gap/mismatch on applicable aircraft. This Directive also introduces a modification to the hook and latch assembly on a limited number of the applicable aircraft.

Source text

Sourced from the Federal Register of Legislation (legislation.gov.au), CC BY 4.0.

1 AD/F100/5 - Powerplant - Lower Cowl Door Engagement