BRISTELL S-LSA, Руководство по техническому обслуживанию и инспекции

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15.CHAPTER
– AEROPLANE REPAIRS
Document: SLSA-MIP-5-4-0-US Date of Issue: 05/2016 Revision: -
15-12
Dust removing
Dust is removed by wiping with a clean and dry brush or by a vacuum cleaner.
Stiffener preparation
For this kind of repairs we recommend the stiffener G (glass) with plain weave, 150 g/m 2
(0.037 lb/ft 2 ), with surface protection for epoxy resins. Number of needed stiffener layers
depends on depth of damage. It is possible to say that each layer of the mentioned fabric
represents at proper saturation by matrix resin thickness of 0.5 mm (0.020 in).
Stiffener layers must be prepared (cut out) gradually from the smallest (the lowest) up to the
bigger (upper), each with overrun of 19 mm (0.75 in).
Putting layers
After preparing lamination mixture (for recommendation of material see Tab. 15-3), it is
applied to the place of repair by means of rigid brush. The first stiffener is laid into the deposit
and it is again saturated by brush. Another layer of stiffener is laid and saturated. When
putting the last layer it is necessary to pay attention to a proper saturation and compression
of stiffeners so that they cannot „come up" to the surface and subsequent useless damage
at final grinding. For better saturation of the surface by resin and securing against curtaining
it is possible to put PE or PP transparent foil across the surface. When applied properly, the
layer is without bubbles. Repair thickness should exceed surrounding surface in this phase
by about 0.5 to 1 mm (0,02 in to 0,04 in) for finishing.
Sanding
Carry out sanding and eventually apply mastic on the surface after setting, eventually tearing
of the foil (see small damage). It is suitable to begin sanding by abrasive with grain size of
160 and finish by grain size of at least 400. Dry sanding equipment is used with suction from
the sanding area. Al2O3 or equivalent can be used as sanding material. It is important not to
diminish basic material of the part at sanding.
NOTE
Especially in case of C/K stiffener in the basic part there must not be any sanding through up
to the stiffener (complication - see the note about preparatory sanding).
Finishing
Refer to 15.6.Paint repairs.
15.5.3.3 Major damage
At such damage we recommend to change the part or to do this repair in a professional
facility. Use instructions in chapter about medium damage as recommendation for used
materials.
15.5.4 Structural parts
On these parts we do not recommend to do other as small damages repair. In case of the
other damage we recommend to contact BRM AERO as manufacturer.
CAUTION
When repairing, it is necessary to pay attention to timely repair (see the text about low of
properties at humidity effect at the beginning of paragraph 15.5.1) !
Small damage
Repairs are made according to instructions with appearance parts.
CAUTION
When repairing, it is necessary to carefully pay attention not to damage the stiffeners!