# AD 76-07-09: Radio Magnetic Indicator

- Type: Airworthiness directive
- Status: Current
- Products: Collins Radio Magnetic Indicator
- Effective: April 19, 1976
- Superseded by: Nothing supersedes this AD
- Product type: Appliance
- Amendment: 39-2570
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/0CEAE29F5A07B94486256A320060BACA.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/76-07-09

## The airworthiness directive

76-07-09 COLLINS: Amendment 39-2570. Applies to Collins Model 332C-10 Radio Magnetic Indicator (part numbers and serial numbers listed below) installed on various aircraft makes and models equipped with 24 V electrical systems:

Collins Part No. Serial No. 622-0555-001 729 and below 622-0555-002 963 and below 622-0555-003 3593 and below, 3595 thru 3600,

3602 thru 3611, 3613 thru 3628 622-0555-004 3693 and below, 3695 thru 3706 622-0555-005 3252 and below 622-0555-006 4156 and below 622-0555-007 3208 and below, 3210 thru 3231,

3233 thru 3239 622-0555-008 2805 and below

Compliance: Required as indicated, unless already accomplished.

To preclude possible erroneous VOR bearing information presentation, with no flag warning, when 26 VAC input power is lost, accomplish the following:

A) Within 50 hours" time in service in service after the effective date of this AD, determine if the 332C-10 Radio Magnetic Indicator(s) is (are) installed, and if so, whether modified in accordance with Collins 332C-10 Radio Magnetic Indicator (622-0555-XXX) Service Bulletin No. 6, dated February 16, 1976, or later approved revision. On those units not modified in accordance with Service Bulletin No. 6, prior to further flight, install a placard on glass face of the magnetic indicator which reads:

"USE ADF MODE ONLY"

and operate the unit in accordance with this limitation.

NOTE: Indicators which have been modified in accordance with Service Bulletin No. 6 will have the No. 6 removed from the modification plate attached to the unit.

B) On or before January 1, 1977, modify the 332C-10 indicators(s) in accordance with Collins 332C-10 Radio Magnetic Indicator (622-0555-XXX) Service Bulletin No. 6, dated February 16, 1976, or later approved revisions.

C) When Paragraph B has been accomplished, compliance with Paragraph A is no longer required.

D) Any alternate method of compliance with this AD must be approvedby the Chief, Engineering and Manufacturing Branch, FAA, Central Region.

This amendment becomes effective April 19, 1976.

## Registered aircraft it may apply to (OpenAirDocs)

No registered aircraft matched the models it names.

Its text cites no advisory circulars or STCs.

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