ENSTROM TH-28/480 Series User manual

ENSTROM TH-28/480 SERIES MAINTENANCE MANUAL
2001 Edition
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Rev. 25
i Aug 22/16
ENSTROM TH-28/480 SERIES MAINTENANCE MANUAL
The Airworthiness Limitations section is FAA approved and specifies
inspections and other maintenance required under 14 CFR §§ 43.16 and
91.403 of the Federal Aviation Regulations unless an alternative program
has been FAA approved.
Copyright 2001-2016 by
The Enstrom Helicopter Corporation
2209 22nd Street
Menominee, Michigan 49858-3515
Telephone: [phone]
Fax: [phone]
www.enstromhelicopter.com

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ENSTROM TH-28/480 SERIES MAINTENANCE MANUAL
Rev. 25
MM-1-3 Aug 22/16
SECTION 1
INTRODUCTION
1-1. Maintenance Manual Arrangement
The maintenance manual sections divide the aircraft into major systems and related
subsystems to provide maintenance procedures required for proper system function and
optimum component service life. Each section details the following maintenance functions for
the associated subsystems and components, if applicable:
General Description
Troubleshooting
Adjustment/Rigging
Removal
Disassembly
Inspections (other than Periodic Inspections)
Repair
Assembly
Installation
1-2. Aircraft Effectivity
The maintenance data presented in this manual is applicable to all TH-28, 480, and 480B model
Enstrom helicopters with standard equipment. Optional equipment maintenance procedures are
included in the TH-28/480 Series Maintenance Manual for common optional equipment that is
installed before aircraft delivery (This does not include avionics installations).
1-3. Maintenance Manual Supplements
Maintenance procedures for optional equipment may be provided in maintenance manual
supplements. These supplements are part of the TH-28/480 Series Maintenance Manual when
an aircraft is equipped with optional equipment which requires a maintenance manual
supplement. The following optional equipment supplements are applicable to the TH-28/480
Series Maintenance Manual.
Supplement 1: Air Conditioning System, P/N 4220176-( ), Revision 7, Dated: Jun 14/11.
Supplement 2: Emergency Pop-Out Floats, P/N 4220091-1 and 4220091-3, Revision 2,
Dated: Feb 20/08.
Supplement 3: Gyrocam Dual or Triple Sensor Camera System, Dated: Feb 8/08.
Supplement 4: Chelton Flightlogic EFIS System, Revision 1, Dated: Nov 9/10.
Supplement 5: Avionic Systems, Revision 13, Dated: Oct 20/15.
Supplement 6: Partial Wide Instrument Panel, Dated: Nov 15/10.
Supplement 7: Bambi Bucket Interface Kit, Dated: Apr 30/13.
Supplement 8: G1000H Integrated Flight Control System, Dated: May 14/14.

ENSTROM TH-28/480 SERIES MAINTENANCE MANUAL
Rev. 21
MM-1-4 Apr 30/14
1-4. Maintenance Manual Changes and Revisions
Subsequent to the publication of the initial issue of the Enstrom TH-28/480 Series Maintenance
Manual, changes in aircraft equipment, support concepts and procedures, as well as information
developed by experience, may affect the contents of the manual. To ensure that coverage in the
manual continues to reflect such changes, revised information is released by one of the
following methods:
(1) Revision - A revision alters portions of the manual by replacement, addition, and/or
deletion of pages. A revision cover page lists the page(s) to be removed and/or inserted.
(2) Reissue - Where large numbers of changes are involved, a complete reissue of the
manual is warranted. Preceding issues of the manual then become obsolete and should
be discarded.
(3) Service Information Letters - Used to transmit information, recommendations, and general
service instructions to the aircraft owner/operator and maintenance personnel. The
information provided in the Service Information Letters will be incorporated into the
maintenance manual as needed at a later date.
(4) Service Directive Bulletins - Used to direct the owner/operator and/or maintenance
personnel to make mandatory changes, improvements, or inspections to the aircraft. The
information provided in the Service Directive Bulletins will be incorporated in the
maintenance manual as needed at a later date. At the time of incorporation, the Service
Directive Bulletin is superseded by the maintenance manual, and accomplishment or sign-
off of the Service Directive Bulletin in the maintenance records book is no longer required.
A detailed entry should be made in the maintenance records to indicate that the Service
Directive Bulletin is superseded by the maintenance manual.
Service Information Letters and Service Directive Bulletins incorporated into the maintenance
manual are logged in the Service Information Letter Index or the Service Directive Bulletin Index
(as appropriate) located on the Enstrom Helicopter website: www.enstromhelicopter.com (follow
the applicable link under the Tech Publications section of the Technical Support page). Each
index numerically lists all Service Information Letters and Service Directive Bulletins,
respectively, and identifies those which have been incorporated into the maintenance manual.
All Service Information Letters and Service Directive Bulletins are also located under the Tech
Publications section of the website.
Enstrom distributes maintenance manual reissues and revisions in hardcopy form via mail to
owners and operators who are registered with Enstrom. Notice of recently released Service
Information Letters and Service Directive Bulletins is provided via a postcard mailing.
Registration to receive publication mailings can be coordinated through Enstrom Product
Support.

ENSTROM TH-28/480 SERIES MAINTENANCE MANUAL
Rev. 20
FAA Approved: May 9, 2013 MM-3-1 Apr 25/13
SECTION 3
AIRWORTHINESS LIMITATIONS
The Airworthiness Limitations section is FAA approved and specifies
inspections and other maintenance required under 14 CFR §§ 43.16 and
91.403 of the Federal Aviation Regulations unless an alternative program
has been FAA approved.
FAA APPROVED BY DATE
MANAGER
CHICAGO AIRCRAFT CERTIFICATION OFFICE
CENTRAL REGION
FEDERAL AVIATION ADMINISTRATION

ENSTROM TH-28/480 SERIES MAINTENANCE MANUAL
Rev. 25
FAA Approved: August 26, 2016 MM-3-2 Aug 22/16
SECTION 3
LOG OF REVISIONS
Rev.
Num.
Rev.
Date
Pages
Affected
Approval
Date
FAA
Approved
1 Oct 10/03 MM-3-2, MM-3-40, MM-3-41 Oct 28/03 Joe McGarvey
2 Jun 2/04
MM-3-2, MM-3-5, MM-3-13, MM-3-14,
MM-3-40
Sep 8/04 Joe McGarvey
3 Oct 13/04
MM-3-2, MM-3-11 thru MM-3-18, MM-3-
40
Nov 09/04 Gregory Michalik
4 Mar 15/05
MM-3-2, MM-3-8, MM-3-33, and MM-3-
40
Mar 25/05 Gregory Michalik
5 Aug 4/06
MM-3-2, MM-3-7, MM-3-8, MM3-31 thru
MM-3-36
Aug 30/06 Shawn Malekpour
6 Apr 16/07
MM-3-2, MM-3-15 thru MM-3-18, MM-3-
31 thru MM-3-36, MM-3-39 thru MM-3-
42
Apr 24/07 Shawn Malekpour
7 Feb 20/08 MM3-1 through MM-3-8 Oct 2/08 Gregory Michalik
8 N/A None N/A N/A
9 Dec 12/08 MM-3-7 through MM-3-8 Mar 3/09 Gregory Michalik
10 N/A None N/A N/A
11 Dec 21/09 MM-3-1, MM-3-2, MM-3-5 thru MM-3-8 Jan 6/10 Gregory Michalik
12 N/A None N/A N/A
13 N/A None N/A N/A
14 N/A None N/A N/A
15 N/A None N/A N/A
16 N/A None N/A N/A
17 Jun 24/11 MM-3-6 Jul 15/11 Gregory Michalik
18 N/A None N/A N/A
19 Dec 10/12 MM-3-6 Jan 10/13 Gregory Michalik
20 Apr 25/13 MM-3-1, MM-3-2, MM-3-6, MM-3-7 May 9/13 Gregory Michalik
21 Apr 30/14 None N/A N/A
22 Jun 25/14 None N/A N/A
23 Jul 3/15 None N/A N/A
24 Dec 4/15 MM-3-2 through MM-3-10 Dec 15/15 Gregory Michalik
25 Aug 22/16 MM-3-2, MM-3-3