WATER WASHING
Report your conclusions and recommen-
dations. Carefully read and follow the pro-
Water washing consists of an emulsion of
cedures in your aircraft maintenance manuals
demineralized water and cleaning liquids. Field
for borescoping. Different procedures are
cleaning of this nature is accomplished as a
required for different types of engines to
desalination wash to remove salt deposits when
prevent damage or to inspect properly. For
operating in salt-laden air. Field cleaning maybe
example, on the turboprop engine, the turbine
done as a performance recovery wash to remove
blade inspection is made easier by releasing
dirt and other deposits.
the propeller brake. This makes it possible
Specific steps to follow in cleaning a particular
to rotate the turbine smoothly in both directions.
engine are found in the maintenance instructions
On turbofan engines, you should not bore-
for the particular engine. These steps generally
scope if there is a possibility that wind can
include blocking some lines and ports and
rotate the fan rotor.
removing any equipment in the inlet duct. This
is done to prevent damage by the cleaning
Although water washing is not required
material. The engine is then motored over for
before borescoping, it helps clean the en-
specific periods of time while the cleaning
gine so you get the best possible evaluation.
compound is fed into the inlet duct. After clean-
Dirt and small carbon particles may obscure
ing, the engine must be returned to its original
small cracks or pitting that could be missed
configuration. The engine is dried by running it.
in a dirty engine. Water washing also im-
Engine performance for trend analysis is often
proves engine performance by removing sulfi-
checked after engine washing.
dation.
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