# AD 49-05-03: Continental Engines Bearing Inserts

- Type: Airworthiness directive
- Status: Current
- Products: Sierra Hotel Aero Navion (Army L-17A) and Navion A (Army L-17B and L-17C)
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Registered aircraft: 633 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/992308DDEE9407DD86256A56006EFB69.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/49-05-03

## The airworthiness directive

49-05-03 NAVION: Applies to Airplanes Equipped With Continental Model E185-3 Engines Having Serial Numbers 4289-D to 5110-D Inclusive, and Engines Which Have Been Equipped at Overhaul With Tri-Metal Front Main Bearing Inserts and Bronze Thrust Washers in Accordance With Continental Bulletin No. M48-7.

To be accomplished as soon as possible but not later than the first major engine overhaul.

Because of unsatisfactory service experience with Continental E185-3 engines equipped with No. 530497 Tri-Metal front main bearing inserts, and with Nos. 530494, 530495, 530544 thrust washers and 530545 dowel pins, these parts must be replaced with the original silver main thrust bearing inserts, Continental No. 40644.

Continental Service Bulletin M48-30 covers this same subject.

(Ryan Navion Field Service Bulletin No. 5 outlines the interim precautions to be taken on airplanes equipped with the unsatisfactory thrust washers until silver main thrust bearings are installed in accordance with this note.)

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A-782](https://openairdocs.org/tcds/A-782): Sierra Hotel Aero Inc.; names 2 of 8 models: Navion (Army L-17A), Navion A (Army L-17B and L-17C)

## 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: 633 (633 by airframe model, 0 by engine model)
- Makers: Ryan 285, North American 249, Navion 99

Models with the most aircraft:

- [North American NAVION](https://openairdocs.org/model/north-american-navion): 203 aircraft (airframe model)
- [Ryan NAVION](https://openairdocs.org/model/ryan-navion): 170 aircraft (airframe model)
- [Ryan NAVION A](https://openairdocs.org/model/ryan-navion-a): 115 aircraft (airframe model)
- [Navion NAVION A](https://openairdocs.org/model/navion-navion-a): 99 aircraft (airframe model)
- [North American NAVION A](https://openairdocs.org/model/north-american-navion-a): 46 aircraft (airframe model)

All 6 models: https://openairdocs.org/ad/49-05-03/models.md
Every aircraft: https://openairdocs.org/ad/49-05-03/aircraft.md

Its text cites no advisory circulars or STCs.

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