AD 61-21-05

Airworthiness directive · Compass Circuit Breakers · Lockheed Martin 188A and 188C

Effective
November 2, 1961
Models
188A, 188C
Data sheet
TCDS4A22
Registered aircraft
4 matched by model
Product
Aircraft · Large airplane

Unofficial copy of the text in the FAA’s Dynamic Regulatory System. The FAA’s own copy is the authoritative one. DRS record last changed May 30, 2024.

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The airworthiness directive

61-21-05 LOCKHEED: Amdt. 342 Part 507 Federal Register October 3, 1961. Applies to All Model 188 Aircraft.

Compliance required as indicated.

Several instances of inadvertent tripping of compass circuit breakers have occurred due to bumping the ganging bar by the occupant of the observers seat. Due to the effect of the loss of heading information upon operational safety, accomplishment of the following is required:

Within the next 100 hours' time in service after the effective date of this AD, inspect the pilot's and copilot's compass circuit breakers, and if the circuit breakers are ganged together, either remove the ganging bars, or install a protective guard which precludes inadvertent operation of the ganging bar. (These circuit breakers are located in the lowest circuit breaker panel beside the observers seat on the left side of the flight deck.)

This directive effective November 2, 1961.

Affected TCDS · 1

The type certificate data sheets for the models this AD names, matched by model and maker.

Registered aircraft · 4

Registered aircraft whose airframe or engine model this AD names. Matched by model only, so check each against the AD’s applicability.

By aircraft maker
  • Lockheed4 aircraft
By year built
19591960
Registered aircraft by year built: 3 aircraft
19592
19601

1 with no year recorded

By model

Aircraft