Aeropro CZ A220, Maintenance Manual

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Maintenance Manual
AEROPRO CZ 16-1
Maintenance Manual
March 21, 2020
Section 16
Structural repair
Table of contents Page
16.1 Structural repair............................................................................ 16-1
16.2
Repair criteria…………………………………………………
16-1
16.3 General consideration for welding frame repair
………….
16-1
16.4 Repair of aircraft skin
…………………………………………
16-1
16.5 Repair of fiberglass parts
………………………………....….
16-1
16.6 Damages of larger extent.
……………………………………
16-1
16.1 Structural repair
16.2 Repair criteria
Although this section outlines repairs permissible on the structure of the aircraft, the decision
of whether to repair or replace a major unit of structure will be influenced by such factors as time and
labor available, and by a comparison of labor costs with the price of replacement assemblies. Past
experience indicates that replacement, in many cases, is less costly than major repair. Certainly,
when the aircraft must be restored to its airworthy condition in a limited length of time, replacement is
preferable. Restoration of a damaged aircraft to its original design strength, shape, and alignment
involves careful evaluation of the damage, followed by exacting workmanship in performing the
repairs. This section suggests the extent of structural repair practicable on the aircraft, and
supplements Federal Aviation Regulation, Part 43. Consult the factory when in doubt about a repair
not specifically mentioned here.
16.3 General consideration for welded frame repair
Minor damages, not affecting the aircraft airworthiness, may be repaired provided the scope
of work does not extend beyond cases described below:
The operator is allowed to carry out only such repairs of the lattice-work in operation that do
not require either use of a welding equipment or application of thermal treatment for straightening.
Straightening of such structural members is permitted if, the deflection does not exceed 3% member
length-member diameter ratio. A
local deflection (depression) not exceeding 5% of tube dimension
in its diameter can be considered admissible provided this tube is not damaged by cracks or some
other non-reversible deformation.
16.4 Repair of aircraft skin
If damage occurs under operation, the skin can be repaired by replacing the whole part of the
damaged fabric, or by a local repair using a patch. Such repairs may be carried out using the same
materials as applied at aircraft fabrication.
16.5 Repair of fiberglass parts
If damage to these parts occurs, only a repair with use of epoxy resins and fiberglass cloth is
applicable. It is necessary to thoroughly clean the surface of the parts under repair up to the base
material and to remove any grease and paint. When making repairs, follow the manufacturers
directions for the use of epoxy materials.
16.6 Damages of larger extent.
When damages of larger extent is found, we recommend to consult the manufacturer. Always
replace parts and components with parts and components of the same material specification.