68-12-03: High Compressor Rotor Blade Failure

FAA order 68-12-03 is an airworthiness directive in force since June 12, 1968. The FAA's subject line: High Compressor Rotor Blade Failure. It names the Pratt & Whitney JT4A-3&5 series engine: about 1 aircraft on the U.S. register today, though an order usually covers particular versions or serial numbers rather than every one. System: engine.

What it applies to as the FAA lists it

Kind of product: Engine
Makes: Pratt & Whitney Division
Models: JT4A-10, JT4A-11, JT4A-12, JT4A-3, JT4A-5, JT4A-9
Engine series: Pratt & Whitney JT4A-3&5 series 1 aircraft

Dates and paperwork

In force since: June 12, 1968
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 (777 characters)

68-12-03	PRATT & WHITNEY:  Amendment 39-608.  Applies to all Model JT4A Series Turbojet Engines. 
	Compliance required as indicated unless previously accomplished.: 
	To preclude penetration of the diffuser case in the event of a high compressor rotor blade failure, accomplish the following: 
	Within the next 11,000 hours' time in service after the effective date of this AD, rework all P/N's 361176, 397231, 419006, 406242, 429614, 447328, and 450862 diffuser case assemblies in accordance with Pratt & Whitney Aircraft Turbojet Engine Service Bulletin No. 1033 dated September 8, 1965, and FAA-approved revisions or an equivalent modification approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. 
	This amendment becomes effective June 12, 1968.

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 October 7, 2026. Connections as data: /graph/directive/68-12-03.json · aircraft systems.