# AD 85-19-01: Rosemount AOA Sensors

- Type: Airworthiness directive
- Status: Current
- Products: Boeing 727-100 Series, 727-100C Series, 727-200 Series, 727-200F Series, 727 Series, 727C Series, 737-100 Series, 737-200 Series, 737-200C Series, 737-300 Series, 737-400 Series, 737-500 Series and 10 more
- Effective: October 12, 1985
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-5134
- Registered aircraft: 1,520 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/7653BD643C8AAAF7862568AA005D2D07.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/85-19-01

## The airworthiness directive

85-19-01 BOEING: Amendment 39-5134. Applies to Boeing Model 767 and 757 series airplanes, and certain Model 737 and 727 series airplanes, certificated in any category, equipped with Rosemount Angle of Attack (AOA) sensors identified as Model 861CAB or 861CAK and modification number 0001. To prevent the hazards associated with a malfunctioning AOA sensor caused by loose resolver and/or damper gears, accomplish the following as indicated below, unless already accomplished:

A. Inspect Model 757 and 767 series airplanes equipped with Rosemount AOA sensors, Model 861CAB, modification number 0001, within 300 flight hours or 30 days, whichever is later, after the effective date of this AD, and thereafter at intervals not to exceed 300 flight hours or 30 days, whichever is later, until the replacement prescribed in subparagraph A.1. or A.2., below, is accomplished:

1. Replace Rosemount AOA sensors, serial numbers 00475 through 00629, within 180 days after the effective date ofthis AD, with a unit bearing modification number 0001A, in accordance with the instructions in paragraph C., below.

2. Replace Rosemount AOA sensors, serial numbers 00001 through 00474, within 360 days after the effective date of this AD, with a unit bearing modification number 0001A, in accordance with the instructions in paragraph C., below.

Inspect in accordance with the appropriate Boeing Alert Service Bulletin, 757-34A0026 or 767-34A30, both dated November 12, 1984, or later FAA approved revision. Units determined to be faulty during inspections must be replaced with a serviceable unit, prior to further flight.

B. Inspect Model 727 and 737 series airplanes equipped with Rosemount AOA sensors, Model 861CAK, modification number 0001, within 300 flight hours or 30 days, whichever is later, after the effective date of this AD, and thereafter at intervals not to exceed 300 flight hours or 30 days, whichever is later, until the replacement required in subparagraph B.1., below, is accomplished:

1. Replace Rosemount AOA sensors, serial numbers 00001 through 00173, within 180 days after the effective date of this AD, with a unit bearing modification number 0001A in accordance with the instructions in paragraph C., below.

Inspect in accordance with paragraph 3 of "Accomplishment Instructions" of the appropriate Boeing Alert Service Bulletin, 727-34A0223 or 737-27A1126, both dated November 12, 1984, or later FAA approved revision. Units determined faulty during inspections must be replaced with a serviceable unit, before further flight.

C. Remove, inspect, and rework Rosemount AOA sensors as specified in paragraphs A. and B., above, in accordance with the appropriate Rosemount Service Bulletin, 861CAB-34-02 or 861CAK-34-01, both dated November 12, 1984, or later FAA approved revision. Units found with both resolver gears loose must be returned to Rosemount for rework.

D. Alternate means of compliance which provide an acceptable level of safety may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region.

E. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of replacements required by this AD.

All persons affected by this directive who have not already received the above specified service bulletins from the manufacturers may obtain copies upon request to the Boeing Commercial Airplane Company, P.O. Box 3707, Seattle, Washington 98124, or Rosemount, Inc., P.O. Box 35129, Minneapolis, Minnesota 55435. They may also be examined at the FAA, Seattle Aircraft Certification Office, 9010 East Marginal Way South, Seattle, Washington.

This amendment becomes effective October 12, 1985.

## Affected data sheets (4) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A16WE](https://openairdocs.org/tcds/A16WE): The Boeing Company; names 9 of 17 models: 737-500 Series, 737-100 Series, 737-200C Series, 737-800 Series, 737-300 Series, 737-200 Series, 737-700 Series, 737-400 Series…
- [TCDS A3WE](https://openairdocs.org/tcds/A3WE): The Boeing Company; names 6 of 6 models: 727-100 Series, 727 Series, 727-200 Series, 727-100C Series, 727-200F Series, 727C Series
- [TCDS A2NM](https://openairdocs.org/tcds/A2NM): The Boeing Company; names 4 of 4 models: 757-200CB Series, 757-200PF Series, 757-300 Series, 757-200 Series
- [TCDS A1NM](https://openairdocs.org/tcds/A1NM): The Boeing Company; names 3 of 5 models: 767-300 Series, 767-200 Series, 767-300F Series

## 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: 1,520 (1,520 by airframe model, 0 by engine model)
- Makers: Boeing 1,520

Models with the most aircraft:

- [Boeing 737-823](https://openairdocs.org/model/boeing-737-823): 278 aircraft (airframe model)
- [Boeing 767-300F](https://openairdocs.org/model/boeing-767-300f): 169 aircraft (airframe model)
- [Boeing 737-800](https://openairdocs.org/model/boeing-737-800): 139 aircraft (airframe model)
- [Boeing 737-824](https://openairdocs.org/model/boeing-737-824): 135 aircraft (airframe model)
- [Boeing 737-832](https://openairdocs.org/model/boeing-737-832): 73 aircraft (airframe model)
- [Boeing 757-232](https://openairdocs.org/model/boeing-757-232): 63 aircraft (airframe model)
- [Boeing 737-890](https://openairdocs.org/model/boeing-737-890): 60 aircraft (airframe model)
- [Boeing 767-332](https://openairdocs.org/model/boeing-767-332): 46 aircraft (airframe model)
- [Boeing 757-224](https://openairdocs.org/model/boeing-757-224): 40 aircraft (airframe model)
- [Boeing 757-222](https://openairdocs.org/model/boeing-757-222): 38 aircraft (airframe model)
- [Boeing 737-724](https://openairdocs.org/model/boeing-737-724): 36 aircraft (airframe model)
- [Boeing 767-322](https://openairdocs.org/model/boeing-767-322): 36 aircraft (airframe model)
- [Boeing 767-323](https://openairdocs.org/model/boeing-767-323): 27 aircraft (airframe model)
- [Boeing 757-223](https://openairdocs.org/model/boeing-757-223): 23 aircraft (airframe model)
- [Boeing 757-236](https://openairdocs.org/model/boeing-757-236): 20 aircraft (airframe model)
- [Boeing 757-251](https://openairdocs.org/model/boeing-757-251): 18 aircraft (airframe model)
- [Boeing 757-351](https://openairdocs.org/model/boeing-757-351): 16 aircraft (airframe model)
- [Boeing 737-790](https://openairdocs.org/model/boeing-737-790): 14 aircraft (airframe model)
- [Boeing 737-752](https://openairdocs.org/model/boeing-737-752): 13 aircraft (airframe model)
- [Boeing 757-231](https://openairdocs.org/model/boeing-757-231): 13 aircraft (airframe model)

All 105 models: https://openairdocs.org/ad/85-19-01/models.md
Every aircraft: https://openairdocs.org/ad/85-19-01/aircraft.md

Its text cites no advisory circulars or STCs.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.
