54-12-02: Vibratory Stresses
FAA order 54-12-02 is an airworthiness directive. The FAA's subject line: Vibratory Stresses. System: propeller.
What it applies to as the FAA lists it
- Kind of product
- Propeller
- Makes
- McCauley Propeller Systems
- Models
- AAF 41D5926, D-1093
Dates and paperwork
- Docket
- Unknown
- Status
- Current
- The FAA's document
- Read the order on the FAA's site
The order itself the regulatory text, as published
Show the full text (2,060 characters)
54-12-02 MCCAULEY: Applies to All McCauley Propellers Having 41D5926 Hub With SS-135-6 Blades and D-1093 Hub With SS-135-6M or SS-138-6 Blades.
Compliance required as indicated.
On the basis of satisfactory vibration stress surveys conducted on the 102-inch diameter configuration, these propellers were approved vibration wise for installation on the Continental W-670-6A and W-670-6N and Lycoming R680 engines. When installed on the Continental engine, the propeller must be indexed in the 0 degree position (blades in line with the crankthrow) and operation is to be restricted between 1,500 and 1,650 r.p.m.
Additional approval were given for the installation of propellers in reduced diameters at a time when the effects on the vibratory stresses resulting from such a reduction were not generally appreciated. Accordingly, some installations were made where the propeller diameter was reduced, as in the Fairchild M-62C. Service experience with this installation and a more thorough knowledge of the vibration problems indicate that diameters below the normal 2 percent reduction that is usually permissible on the basis of a stress survey have resulted in serious failures. Accordingly, to preclude additional propeller failures, the following should be performed. Compliance required prior to July 1, 1954.
(a) To preclude failures due to vibratory conditions, remove from service all of these propellers in diameters outside the 102- to 100-inch limits.
(b) To preclude fatigue failures due to corrosion or galling in the blade shank region and/or hub, disassemble propellers maintained in service (diameters 102 to 100 inches) and magnetically inspect hub and blades at intervals not exceeding 100 hours. The propeller blade and hub surface must be kept free from corrosion at all times.
If 100 hours operating time has not been accumulated since an inspection was conducted on the propeller as provided in AD 47-43-09, it will be satisfactory to operate until 100 hours have been accumulated.
This supersedes AD 47-43-09.
Source: FAA Dynamic Regulatory System, airworthiness directives. The FAA's document is the authority; the register counts are this site's, from the FAA register of November 6, 2026. Connections as data: /graph/directive/54-12-02.json · aircraft systems.