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FAA orders · airworthiness directive · historical

79-20-08: Induction System

FAA order 79-20-08 is an airworthiness directive in force since October 8, 1979. The FAA's subject line: Induction System. It names Great Lakes 2: about 168 aircraft on the U.S. register today, though an order usually covers particular versions or serial numbers rather than every one. System: other and general.

What it applies to as the FAA lists it

Kind of product
Aircraft
Makes
Great Lakes Aircraft Company, LLC (John Duncan)
Models
2T-1A-1, 2T-1A-2
On this site
Great Lakes 2 168 registered

Dates and paperwork

In force since
October 8, 1979
Docket
Unknown
Replaced by
2004-25-22
Status
Historical
The FAA's document
Read the order on the FAA's site

The order itself the regulatory text, as published

Show the full text (1,699 characters)
79-20-08 GREAT LAKES: Amendment 39-3580. Applies to Models 2T-1A-1 and 2T- 1A-2 airplanes having a Lycoming IO-360-B1F6 or AIO-360-B1G6 engine installed. \n\n\tCOMPLIANCE: Required as indicated unless already accomplished. \n\n\tTo preclude engine induction system blockage by pieces of failed alternate air doors and resulting power loss, accomplish the following: \n\n\tA)\tWithin the next 25 hours time-in-service after the effective date of this AD: \n\n\t\t1.\tVisually inspect the aircraft induction system drain fitting located in the induction elbow below the fuel injector for blockage or restriction. If the hole is restricted in the weld area or not drilled through the elbow, before further flight open up the restricted hole or drill a hole in the elbow at the fitting location using a No. 10 (.193) drill. \n\n\tB)\tWithin 25 hours time-in-service after the effective date of this AD and each 100 hours time-in-service thereafter: \n\n\t\t1.\tVisually inspect the alternate air door for distortion, heat damage and cracks. If any of these conditions are noted, before further flight repair the existing door or fabricate and install a new door in accordance with Figure I of this AD. \n\n\t\t2.\tVisually inspect the induction system including the filter for cleanliness, security and damage from backfire or induction system fires. Before further flight, repair or replace any damaged components necessary to restore the system to an airworthy condition. \n\n\tC)\tAny equivalent method of compliance with this AD must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region. \n\n\tThis amendment becomes effective on October 8, 1979. \n\n\nFIGURE 1

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 5, 2026. Connections as data: /graph/directive/79-20-08.json · aircraft systems.