# Proposed AD 99-NM-252-AD: Lockheed Model L-1011-385 Series Airplanes

- Type: Proposed airworthiness directive (not in force)
- Status: Became AD 99-13-08 R1
- Action: Notice of proposed rulemaking (NPRM).
- Published: November 8, 1999, 64 FR 60750
- Comments due: December 23, 1999
- Became: [AD 99-13-08 R1](https://openairdocs.org/ad/99-13-08-R1)
- Docket: 99-NM-252-AD
- FR document: 99-29180
- Official PDF: https://openairdocs.org/files/sha256/99/63/99635cfc236b8ae98322df8c840ef22cabb63948061b396d7ce81f84d6ad6971 (from https://www.govinfo.gov/content/pkg/FR-1999-11-08/pdf/99-29180.pdf)
- Federal Register: https://www.federalregister.gov/documents/1999/11/08/99-29180/airworthiness-directives-lockheed-model-l-1011-385-series-airplanes
- Page: https://openairdocs.org/proposed/99-NM-252-AD

## Summary

This document proposes to revise an existing airworthiness directive (AD), applicable to all Lockheed Model L-1011-385 series airplanes, that currently requires inspections to detect cracking and other discrepancies of certain web-to-cap fasteners of the rear spar between inner wing station (IWS) 310 and IWS 343, and of the web area around those fasteners; various follow-on actions; and modification of the web-to-cap fastener holes of the rear spar between IWS 299 and IWS 343, which, when accomplished, defers the initiation of the inspections for a certain period of time. The actions specified by that AD are intended to prevent fatigue cracking in the web of the rear spar of the wing, which could result in failure of the rear spar of the wing and consequent fuel spillage. This action would, for certain airplanes, extend the compliance time for the modification of the web-to-cap fastener holes, and would eliminate references to modification of the outboard spar.

## Notices in this docket

- Nov 8, 1999: Notice of proposed rulemaking (NPRM). (first notice), FR document 99-29180, comments due Dec 23, 1999 (https://www.federalregister.gov/documents/1999/11/08/99-29180/airworthiness-directives-lockheed-model-l-1011-385-series-airplanes)

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