# AD 68-11-01: Localizer Receiver Information

- Type: Airworthiness directive
- Status: Current
- Products: Boeing 707-100 Long Body, 707-100B Long Body, 707-100B Short Body, 707-200, 707-300 Series, 707-300B Series, 707-300C Series and 707-400 Series
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-605
- Registered aircraft: 6 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/5B44D06B18401A6A8625682E00628C3D.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/68-11-01

## The airworthiness directive

68-11-01 BOEING: Amendment 39-605. Applies to Model 707 Series airplanes equipped with Collins Model 51RV-1 navigation receivers and Pratt & Whitney P/N 563586 or General Laboratories P/N 42721 solid state engine ignitor systems. Compliance required as indicated. Reports indicate a localizer course indicator error may exist when the Pratt & Whitney P/N 563586 or General Laboratories P/N 42721 solid state engine ignitors are turned "ON". Since this unsafe condition is likely to exist in other Boeing Model 707 Series airplanes, the Director determined that: A. Flight operations shall not be predicated on the use of localizer receiver information when engine ignition systems are "ON". B. The operating limitations specified in subparagraph A of this paragraph must be placed in the aircraft in the form of a placard in clear view of the pilot. For purposes of this AD any documents including a pilot check list including these limitations constitute a placard within the meaningof this paragraph. C. This limitation does not apply when a 1000 microfarad 50 volt capacitor has been installed across the 28 volt DC input lead to the Collins 51RV-1 receiver in the radio junction box in accordance with Boeing telegraphic Alert Bulletin 2752 dated May 10, 1968, or an equivalent suppression system approved by the Western Region Aircraft Engineering Division. This amendment becomes effective on May 31, 1968, for all persons except those to whom it was made effective immediately by telegram dated May 10, 1968.

## Affected data sheets (2) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 4A21](https://openairdocs.org/tcds/4A21): The Boeing Company; names 4 of 4 models: 707-100B Short Body, 707-200, 707-100 Long Body, 707-100B Long Body
- [TCDS 4A26](https://openairdocs.org/tcds/4A26): The Boeing Company; names 4 of 4 models: 707-300B Series, 707-400 Series, 707-300 Series, 707-300C 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: 6 (6 by airframe model, 0 by engine model)
- Makers: Boeing 6

Models with the most aircraft:

- [Boeing 707-338C](https://openairdocs.org/model/boeing-707-338c): 2 aircraft (airframe model)
- [Boeing 707-368C](https://openairdocs.org/model/boeing-707-368c): 1 aircraft (airframe model)
- [Boeing 707-321B](https://openairdocs.org/model/boeing-707-321b): 1 aircraft (airframe model)
- [Boeing 707-323B](https://openairdocs.org/model/boeing-707-323b): 1 aircraft (airframe model)
- [Boeing 707-351B](https://openairdocs.org/model/boeing-707-351b): 1 aircraft (airframe model)

All 5 models: https://openairdocs.org/ad/68-11-01/models.md
Every aircraft: https://openairdocs.org/ad/68-11-01/aircraft.md

Its text cites no advisory circulars or STCs.

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