Service Bulletin No. 11 rev. A
AVIAT HUSKY A-1 · Service Bulletins
Overview
This service bulletin provides mandatory inspection requirements for the elevator horns of the Aviat Husky A-1 series aircraft. It details the potential failure causes and outlines compliance steps for aircraft owners and operators.
- Mandatory inspections for elevator horns on affected Husky A-1 models.
- Elevator horn failures may result from improper rigging of horizontal stabilizers.
- Cracks in elevator horns can lead to failure if not detected in time.
- All elevator assemblies with specific part numbers are affected.
- Inspections should be performed at each annual inspection.
- Only FAA certified mechanics should perform the required work.
- A compliance letter must be submitted to Aviat Aircraft after inspection.
Document
Source
Originally published by aviataircraft.com. Sprinkle hosts a reference copy with an added summary, specifications and searchable full text.
Document details
- Type ·
- Service Bulletins
- Year ·
- 2021
- File size ·
- 1.4 MB
- Publisher ·
- aviataircraft.com
- Language ·
- en
Specifications & performance
Extracted from this document.
Specifications
- Elevator horn part numbers ·
- 35008-501 through 35008-506
What is the Service Bulletin No. 11 rev. A?
The Service Bulletin No. 11 rev. A is a service bulletins for the AVIAT HUSKY A-1, dated 2021.
Where does the Service Bulletin No. 11 rev. A come from?
This copy of the Service Bulletin No. 11 rev. A was originally published by aviataircraft.com and is hosted on Sprinkle as a free, searchable reference copy.
What year was the Service Bulletin No. 11 rev. A published?
The Service Bulletin No. 11 rev. A — the AVIAT HUSKY A-1 service bulletins on file — is dated 2021.
Most owners only have the POH. Here's the essential set for the AVIAT HUSKY A-1.
- Pilot's Operating Handbook / AFM
- Checklist
- Maintenance Manual
- Parts Catalog (IPC)
- Systems & Wiring
- Service Bulletins on file
- Type Certificate (TCDS)
More AVIAT HUSKY A-1manuals & documents
- INSTRUCTIONS FOR CONTINUED AIRWORTHINESS FOR AVIAT AIRCRAFT A-1, A-1A, A-1B, A-1C-180, A-1C-200Maintenance Manual
- Service Bulletin No. 25Service Bulletins
- SERVICE BULLETIN No. 16Service Bulletins
- Husky InstructionsParts Catalog
- SERVICE BULLETIN No. 14 AVIAT AIRCRAFT INC.Service Bulletins
- Husky A-1B Pilot's Operating HandbookPilot's Operating Handbook
In this document
Purpose
To inform aircraft owners and operators of mandatory inspections on elevator horns for specific Husky A-1 models.
Description
Elevator horn failures may be due to improper rigging, causing bending loads that can induce cracks.
Compliance
Inspect elevator horns for cracks and check tail surface rigging for dihedral at each annual inspection.
Accomplishment Instructions
Step-by-step instructions for inspecting and potentially replacing elevator horns.
Compliance Letter
A form to certify compliance with the service bulletin, including inspection results.
Safety notes
- Only FAA certified mechanics should perform the instructions in this service bulletin.
- It is the responsibility of the owner/operator to ensure compliance by certified mechanics.
- Cracks found in elevator horns require immediate replacement.
Full document text
SERVICE BULLETIN NO. 11 Aviat Aircraft Inc. 1 Husky Service Bulletin No. 11 P.O. Box 1240 Afton, WY 83110 USA Tel: 307-885-3151 Fax: 307-885-9674 e-mail: aviat@aviataircraft.com DATE: 24 SEP 2021 SUBJECT: Elevator Horn REVISION: A AIRCRAFT MODEL AFFECTED: Husky A-1, A-1A, A-1B, A-1C-180 & A-1C-200 ALL AIRCRAFT SERIAL NUMBERS AFFECTED (CERTIFIED IN ANY AIRWORTHINESS CATEGORY) PURPOSE To inform aircraft owners and operators of affected aircraft models and serial numbers listed above of a Mandatory Requirement to perform inspections on elevator horns. DESCRIPTION Examination of elevator horn failures and a study of possible causes indicates that the failures may be due to improper rigging of the horizontal stabilizers on the aircraft. This results in a slight amount of dihedral which causes a bending load on the elevator horns when the elevator is operated through its range of travel. After enough bending cycles, a crack can be induced, and if not discovered in time, will progress until failure of the horn occurs. The elevator horn serves as an attachment point for the elevator control system. All elevator assemblies, both right and left, part numbers 35008-501 through 35008-506, are affected by this service bulletin. COMPLIANCE At each annual inspection, inspect the elevator horns on both elevators for signs of cracks in the vicinity of the weld attachment to the elevator spar. In addition, the rigging of the tail surfaces must be checked to ensure that the stabilizers are not rigged with any dihedral. Rigging instructions can be found in the “Instructions for Continued Airworthiness” for the applicable aircraft model. SERVICE BULLETIN NO. 11 Aviat Aircraft Inc. 2 Husky Service Bulletin No. 11 TABLE OF CONTENTS Purpose, Description, & Compliance……………………........…...…….…...1 Table of Contents & Accomplishment Instructions….………………………. 2-5 Compliance Letter…...………….……………………………………………….6 *NOTE: • Only FAA certified mechanics should perform the instructions in this service bulletin. • It is the responsibility of owner/operator to have only FAA certified mechanics perform this work. • Send the completed compliance letter to Aviat Aircraft, Inc. at the provided address. ACCOMPLISHMENT INSTRUCTIONS Step 1. Locate and remove the two inspection covers from the vertical tail section just above and below the elevators, see figure 1. The use of the applicable section of the illustrated parts catalog (IPC) on tail surface installation can be helpful with disassembly and reinstallation. Figure 1, inspection holes SERVICE BULLETIN NO. 11 Aviat Aircraft Inc. 3 Husky Service Bulletin No. 11 Step 2. Remove the three AN 3 bolts from the elevator horns and the elevators will be disconnected from each other and from the elevator control rod, see figure 2. Figure 2, AN 3 bolts (View looking up) Step 3. Next remove the AN4 bolts holding both elevators to the horizontal stabilizers, see figure 3. Figure 3, AN4 bolt SERVICE BULLETIN NO. 11 Aviat Aircraft Inc. 4 Husky Service Bulletin No. 11 Step 4. With the AN 3 and the AN 4 bolts removed the elevators can be removed from the fuselage by sliding the elevator outboard until the elevator slides off the bearing in the fuselage, see figure 4. Then tip the elevator outboard end down and remove the elevator. Care should be used when removing the elevators to avoid tearing the fabric on the fuselage with the elevator horns. Figure 4, Elevator bearing (stabilizer removed for clarity) Step 5. Inspect the elevator horns for cracks in the area of the weld attachment to the elevator spar, see figure 5. If no cracks are found in the elevator horns, the elevators can be reinstalled in the reverse order as removed. The Instructions for Continued Airworthiness can be helpful with reinstalling the elevators. All self-locking nuts must be replaced during reinstallation and all nuts should be installed using the torques values as specified by AC 43.13-1. If during the inspection, cracks are found in an elevator horn, the elevator horn must be replaced. In addition, the rigging of the tail surfaces must be checked to ensure that the horizontal stabilizers are not rigged with any dihedral. Rigging instructions can be found in the Instructions for Continued Airworthiness for the applicable aircraft model. SERVICE BULLETIN NO. 11 Aviat Aircraft Inc. 5 Husky Service Bulletin No. 11 Figure 5 Elevator horn attachment to the elevator spar Step 6. Make a logbook entry recording the results of this inspection. Step 7. Complete the service bulletin compliance letter and return to Aviat Aircraft Inc. SERVICE BULLETIN NO. 11 Aviat Aircraft Inc. 6 Husky Service Bulletin No. 11 COMPLIANCE LETTER This is to certify that I have complied with Service Bulletin 11 on airplane: Model Number: ___________ Serial No: ___________ Registration Number: __________ Aircraft Hours: __________ Date: ___________ Were cracks discovered on the elevator horns during this inspection: Yes: ___ No: ___ Horizontal tail rigging: Dihedral: _______ No Dihedral: _______ FAA Certified Repairman: ____________________________________ License No.: __________________ Signed: _______________________________________ Comments: ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ Return completed compliance letter to: Aviat Aircraft, Inc. Engineering Department P.O. Box 1240 Afton, WY 83110 Fax: 307-885-9674 Email: engineering@aviataircraft.com