# Proposed AD 98-NM-326-AD: McDonnell Douglas Model DC-9-80 Series Airplanes and Model MD-88 Airplanes

- Type: Proposed airworthiness directive (not in force)
- Status: Became AD 2001-06-16
- Action: Supplemental notice of proposed rulemaking; reopening of comment period.
- Published: April 28, 2000, 65 FR 24882
- Comments due: June 12, 2000
- Became: [AD 2001-06-16](https://openairdocs.org/ad/2001-06-16)
- Docket: 98-NM-326-AD
- FR document: 00-10672
- Official PDF: https://openairdocs.org/files/sha256/b1/0e/b10e0ba39b667b2147a551d16d3755dff2d19e406b9d5fd1240d69a43273c718 (from https://www.govinfo.gov/content/pkg/FR-2000-04-28/pdf/00-10672.pdf)
- Federal Register: https://www.federalregister.gov/documents/2000/04/28/00-10672/airworthiness-directives-mcdonnell-douglas-model-dc-9-80-series-airplanes-and-model-md-88-airplanes
- Page: https://openairdocs.org/proposed/98-NM-326-AD

## Summary

This document revises an earlier proposed airworthiness directive (AD), applicable to all McDonnell Douglas Model DC-9-80 series airplanes and Model MD-88 airplanes, that would have superseded an existing AD that currently requires revisions to the Airplane Flight Manual (AFM) and installation of tufts and triangular decals on the wing upper surfaces. The proposed AD would have required installation of an overwing heater blanket system or a primary wing ice detection system and a new AFM revision. For certain airplanes, this action proposes new repetitive tests and a one-time inspection, as applicable, to ensure the integrity of the electrical installation of the overwing heater blanket, and corrective action, if necessary. This new action also proposes installation of a heater protection panel or an equipment protection device on certain overwing heater blanket systems, which would constitute terminating action for the new repetitive tests for affected airplanes. The actions specified by this proposed AD are intended to prevent ice accumulation on the wing upper surfaces, which could result in ingestion of ice into one or both engines and consequent loss of thrust from one or both engines.

## Notices in this docket

- Mar 8, 1999: Notice of proposed rulemaking (NPRM). (first notice), FR document 99-5549, comments due Apr 22, 1999 (https://www.federalregister.gov/documents/1999/03/08/99-5549/airworthiness-directives-mcdonnell-douglas-model-dc-9-80-series-airplanes-and-model-md-88-airplanes)
- Apr 28, 2000: Supplemental notice of proposed rulemaking; reopening of comment period., FR document 00-10672, comments due Jun 12, 2000 (https://www.federalregister.gov/documents/2000/04/28/00-10672/airworthiness-directives-mcdonnell-douglas-model-dc-9-80-series-airplanes-and-model-md-88-airplanes)

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