# AD 59-18-04: Wing Spar Web Reinforcement

- Type: Airworthiness directive
- Status: Current
- Products: Lockheed 1049C-55, 1049D-55, 1049E-55, 1049G-82 and 1049H-82
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Registered aircraft: 1 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/2431461C964C70B98625696F0047EF4F.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/59-18-04

## The airworthiness directive

59-18-04 LOCKHEED: Applies to All Models 1049C, 1049D, 1049E, 1049G and 1049H Aircraft.

Compliance required as indicated.

The following inspections have been established as a result of recently found cracking in the inner wing rear spar web at Wing Station 458.

At the next block overhaul or 4,000 flight-hours, whichever occurs first, on all aircraft (regardless of accumulated flight time) inspect the inner wing rear spar web at Station 458 for cracks in the upper and lower notched web area shown in Lockheed Drawing 555353. Inspection is applicable to both left and right wings.

If cracks are discovered incorporate the reinforcements shown in Lockheed Drawing 555353, or equivalent.

If no cracks are discovered, the reinforcements shown in Lockheed Drawing 555353 may be incorporated. Otherwise, reinspection at 4,000 flight-hour periods or block overhaul, whichever is less, is required to insure detection of cracks.

(Lockheed Service Letter FS/231094 covers thissame subject.)

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 6A5](https://openairdocs.org/tcds/6A5): Lockheed Martin Aeronautics Company; names 5 of 8 models: 1049G-82, 1049C-55, 1049E-55, 1049D-55, 1049H-82

## Registered aircraft it may apply to (OpenAirDocs)

Matched by airframe and engine model; the AD's applicability may narrow it by serial number, part number or equipment.

- Aircraft: 1 (1 by airframe model, 0 by engine model)
- Makers: Lockheed 1

Models with the most aircraft:

- [Lockheed 1049H-82](https://openairdocs.org/model/lockheed-1049h-82): 1 aircraft (airframe model)

All 1 models: https://openairdocs.org/ad/59-18-04/models.md
Every aircraft: https://openairdocs.org/ad/59-18-04/aircraft.md

Its text cites no advisory circulars or STCs.

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