GDMMTA582-1G
Version 0010
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Balancing
Balancing the propeller should not be necessary if the damage allowances are observed;
repairs should only replace exactly what has been removed.
If there is any doubt or if propeller balancing is necessary, the propeller must be returned
to Air Creation or manufacter Arplast-helice.
Leading Edge Tape
The propeller blade types Ecoprop DL3 are supplied with a light grade of Urethane
Protective Tape applied. This will help the propeller resist the abrasive effects of dust,
sand & water etc. It will not stop solid objects from damaging the blade, although it will
help reduce the damage. If the tape is damaged, it has done its job and should be replaced
except if the blade is damaged under the tape. In this case, the tape must stay in place
until the reparation has been done, in order to protect the dent from engine exhaust
fumes.
Damage Allowances
All propellers will eventually suffer damage from a variety of causes and in differing
degrees.
Varieties of damage such as water, stones, gravel & sand makes it very difficult to
specify maximum damage levels before the blade should be replaced rather than repaired.
The propeller’s design and material (unlike wood, metal) is to progressively increase
strength from tip to root. As such a solid tip strike is not likely to destroy the hub or root
of the blade, (leading to a catastrophic failure) Damage is far more likely at the tip (as tip
speed is much higher) but less critical as it has less force acting upon it (compared to the
root/hub). As all force is focused on the root and hub sections – these areas are not likely
to be damaged. If any doubt exists as to the airworthiness of a propeller, have it properly
assessed prior to flight.
Surface Scratches
The inner 250mm of the prop should not be damaged any further than minor nicks and
paint scratches and the sleeve between the root and the aluminium foot. This is because it
is exposed to the most force. This area is harder to damage than further out on the radius
because the speeds are lower but they could be signs of delamination, cracks or surface
deformations. These signs means that a internal structural break exist. The complete
break of the blade is not far. The propeller must not be used anymore before examination
by Air Creation, the manufacter Arplast-helice or an engineer, or equivalent technician,
who has experience with composite materials. Except this extreme case, as a guide, there
should be no more than three scratches of 0.1mm deep, and 25% of the chord in this area
of the blade.
From a radius of 250mm from the hub to the tip of the propeller the depth allowance is
slightly greater at 0.15mm and extending a maximum of 25% of the chord but the fibers
of the material must not be seen. Slightly more damage is allowed toward the tip. There
should not be a concentration of scratches in one area, even if they don’t affect safety,
they must be repaired as soon as possible.
Summary of Contents for Skypper 582 S
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