# Proposed AD 98-NM-340-AD: McDonnell Douglas Model MD-90-30 Series Airplanes

- Type: Proposed airworthiness directive (not in force)
- Status: Became AD 99-21-32
- Action: Notice of proposed rulemaking (NPRM).
- Published: February 9, 1999, 64 FR 6259
- Comments due: March 26, 1999
- Became: [AD 99-21-32](https://openairdocs.org/ad/99-21-32)
- Docket: 98-NM-340-AD
- FR document: 99-3034
- Official PDF: https://openairdocs.org/files/sha256/29/8c/298c40b038ec062a3095afd90e7f8a861e3f758cdaeb970f414b4219cb188fcd (from https://www.govinfo.gov/content/pkg/FR-1999-02-09/pdf/99-3034.pdf)
- Federal Register: https://www.federalregister.gov/documents/1999/02/09/99-3034/airworthiness-directives-mcdonnell-douglas-model-md-90-30-series-airplanes
- Page: https://openairdocs.org/proposed/98-NM-340-AD

## Summary

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain McDonnell Douglas Model MD-90-30 series airplanes. This proposal would require a one-time inspection to measure clearance and detect interference between the elevator cable pulley and the shroud frame of the ventral stairway, and modification of the shroud frame of the ventral stairway. This proposal is prompted by reports of pitch oscillation of several Model MD-90-30 series airplanes. The actions specified by the proposed AD are intended to prevent interference between the elevator cable pulley and the shroud frame of the ventral stairway, which could result in pitch oscillation of the airplane, and consequent damage to the elevator cable pulley and reduced controllability of the airplane.

## Notices in this docket

- Feb 9, 1999: Notice of proposed rulemaking (NPRM). (first notice), FR document 99-3034, comments due Mar 26, 1999 (https://www.federalregister.gov/documents/1999/02/09/99-3034/airworthiness-directives-mcdonnell-douglas-model-md-90-30-series-airplanes)

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