# Proposed AD 99-NM-220-AD: Fokker Model F.28 Mark 1000, 2000, 3000, and 4000 Series Airplanes

- Type: Proposed airworthiness directive (not in force)
- Status: Became AD 2001-20-08
- Products: Fokker Services B.V.
- Product type: Aircraft
- Action: Supplemental notice of proposed rulemaking; reopening of comment period.
- Published: May 4, 2001, 66 FR 22479
- Comments due: May 29, 2001
- Became: [AD 2001-20-08](https://openairdocs.org/ad/2001-20-08)
- Docket: 99-NM-220-AD
- FR document: 01-11227
- Official PDF: https://openairdocs.org/files/sha256/ba/ea/baeacb00a708b1c5e1b0ec98b0e49b8cf3d5f6675b5f26bb749cc426584aa32c (from https://www.govinfo.gov/content/pkg/FR-2001-05-04/pdf/01-11227.pdf)
- Federal Register: https://www.federalregister.gov/documents/2001/05/04/01-11227/airworthiness-directives-fokker-model-f28-mark-1000-2000-3000-and-4000-series-airplanes
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/80E7A3413EE60FB386256A5C005A28A2.0001
- Page: https://openairdocs.org/proposed/99-NM-220-AD

## Summary

This document revises an earlier proposed airworthiness directive (AD), applicable to certain Fokker Model F.28 Mark 1000, 2000, 3000, and 4000 series airplanes. The proposed AD would have required an eddy current inspection to detect cracks in the upper girder of the two main landing gear (MLG) brackets; and repair of a cracked bracket followed by repetitive inspections, or replacement of a cracked MLG bracket with an improved bracket, as applicable. The proposed AD also provided for an optional terminating action for certain proposed requirements. That proposal was prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. This new action revises the proposed rule by adding new repetitive inspections for certain airplanes, and extending the repetitive interval for the repetitive inspections for other airplanes. The actions specified by this new proposed AD are intended to detect and correct cracks in the upper girder ofthe MLG bracket, which could progress into the vertical stiffeners of the MLG bracket and result in reduced structural integrity of the landing gear.

## Notices in this docket

- Nov 15, 1999: Notice of proposed rulemaking (NPRM). (first notice), FR document 99-29743, comments due Dec 15, 1999 (https://www.federalregister.gov/documents/1999/11/15/99-29743/airworthiness-directives-fokker-model-f28-mark-1000-2000-3000-and-4000-series-airplanes)
- May 4, 2001: Supplemental notice of proposed rulemaking; reopening of comment period., FR document 01-11227, comments due May 29, 2001 (https://www.federalregister.gov/documents/2001/05/04/01-11227/airworthiness-directives-fokker-model-f28-mark-1000-2000-3000-and-4000-series-airplanes)

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