Czech Aircraft CRUISER AIRCRAFT PS-28 Cruiser 2021, Руководство по обслуживанию

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PS-28 Cruiser
PS-28N Cruiser
CR-MM-1-0-00
CHAPTER 15 – AIRPLANE REPAIRS
Revision No.: - Date of issue: 2011-03-08
15 - 6
(c) Damage with disturbance of basic structural elements of the aircraft. (Deformation of
wing and stabilizer spar, deformation of wing ribs, fuselage bulkheads etc.). These
repairs can be made only by Czech Aircraft Group s.r.o. as producer or by authorized
repair shop - for more detailed information contact Czech Aircraft Group s.r.o.
15.4.3 Principles for repair method determination
When repairing the damaged skin or airplane structure keep the following principles:
(a) Drill of the loose or damaged rivets and replace them with new rivets
(see 15.2).
(b) Strength in any section of the repaired place must be as a minimum equal to the
strength of the original part.
(c) Use the same material for repairs as the material of a defective area (for survey of used
materials see Section 17.3).
(d) Carry out repair of skin damaging by means of patches having the same thickness as
the original skin or higher.
(e) Repair the angle defects with inserted angles with the section by 10 to 20% higher than
the section of the damaged angle (see 15.4.4).
(f) Loading from one side of the repaired area must carried through the repair element
directly to the other side.
(g) Length of overlapping in the area of repair must be satisfactorily big so that loading can
be equally distributed to non defective part of the structure.
(h) Exist holes are, if possible, used for riveted joints. If these rivets are not able to transfer
loading, drill other holes. Rivets around of the repaired area are a criterion for rivet size
selection.
(i) Minimum distances of rivets from the edge of sheet metals or inserted bands are shown
in the Table 15-3:
Rivet diameter
Distance of rivet axis from the edge of the sheet metal (angle)
minimum recommended
2.4 mm ( 3/32 in ) 5 mm ( 0.2 in ) 7 mm ( 0.27 in )
3.2 mm ( 1/8 in ) 6 mm ( 0.24 in ) 7 mm ( 0.27 in )
4.0 mm ( 5/32 in ) 7 mm ( 0.27 in ) 8 mm ( 0.31 in )
Tab. 15-2 : Minimum distance of rivets from the edge
15.4.4 Angle repair
Repair method consists in stiffening the damaged angle by means of the new one. When
repairing observes the following instructions:
(a) Determine the section area of the damaged angle S
1
.
(b) Choose S
2
= 1.1 S
1
as section area of the stiffening angle.
(c) Thickness t
2
= (1 to 1. 3) t
1
.
(d) Drill of rivets in the area of repair.
(e) Choose the same rivet diameter as in the damaged place.