# AD 48-14-03: Wing Center Section Spar

- Type: Airworthiness directive
- Status: Current
- Products: Textron Army AT-11 and C18S
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Registered aircraft: 13 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/125B71713FC77AED86256A1C0072ED88.0001
- DRS record last changed: January 21, 2026
- Page: https://openairdocs.org/ad/48-14-03

## The airworthiness directive

48-14-03 BEECH: Applies to Models AT-11 and C18S.

Compliance required by next periodic inspection but not later than July 1, 1948.

Inspect the lower member of the center section main wing spar in the landing gear nacelle area for evidence of wear caused by chafing of the cabin heater control housing. To prevent chafing either use clamps to support housing or cover control housing with 20-inch length of synthetic rubber hose.

## Affected data sheets (2) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A-2-582](https://openairdocs.org/tcds/A-2-582): Textron Aviation Inc.; names 1 of 2 models: Army AT-11
- [TCDS A-757](https://openairdocs.org/tcds/A-757): Textron Aviation Inc.; names 1 of 1 models: C18S

## 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: 13 (13 by airframe model, 0 by engine model)
- Makers: Beech 13

Models with the most aircraft:

- [Beech C18S](https://openairdocs.org/model/beech-c18s): 13 aircraft (airframe model)

All 1 models: https://openairdocs.org/ad/48-14-03/models.md
Every aircraft: https://openairdocs.org/ad/48-14-03/aircraft.md

Its text cites no advisory circulars or STCs.

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