# Proposed AD 97-NM-92-AD: Mitsubishi Model YS-11 Series Airplanes

- Type: Proposed airworthiness directive (not in force)
- Status: Became AD 99-10-16
- Action: Notice of proposed rulemaking (NPRM).
- Published: July 9, 1998, 63 FR 37080
- Comments due: August 10, 1998
- Became: [AD 99-10-16](https://openairdocs.org/ad/99-10-16)
- Docket: 97-NM-92-AD
- FR document: 98-18156
- Official PDF: https://openairdocs.org/files/sha256/a8/bc/a8bc72c58f0eb0f60fba083dc623d98a663d2d4114e99e0d93f84dca20346af4 (from https://www.govinfo.gov/content/pkg/FR-1998-07-09/pdf/98-18156.pdf)
- Federal Register: https://www.federalregister.gov/documents/1998/07/09/98-18156/airworthiness-directives-mitsubishi-model-ys-11-series-airplanes
- Page: https://openairdocs.org/proposed/97-NM-92-AD

## Summary

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to all Mitsubishi Model YS-11 series airplanes. This proposal would require repetitive inspections to detect fatigue cracking in the manhole doublers of the lower wing panels; and repair, if necessary. This proposal also would require eventual modification of screw holes in the manhole doublers of the lower wing panels. This proposal is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by the proposed AD are intended to detect and correct fatigue cracking in the manhole doublers of the lower wing panels, which could result in failure of the wing structure.

## Notices in this docket

- Jul 9, 1998: Notice of proposed rulemaking (NPRM). (first notice), FR document 98-18156, comments due Aug 10, 1998 (https://www.federalregister.gov/documents/1998/07/09/98-18156/airworthiness-directives-mitsubishi-model-ys-11-series-airplanes)

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