737 MAX Flight Crew Operations Manual
Supplementary Procedures -
Adverse Weather
SP.16.20
MN-FLT-OH-201
Operation in a Sandy or Dusty Environment
The main hazards of a sandy or dusty environment are erosion (especially
of engine fan blades), accumulation of sand or dust on critical surfaces and
blockage. The effects of sand ingestion occur predominantly during
takeoff, landing and taxi operations. The adverse effects, however, can
occur if the airplane’s flight path was through a cloud of visible sand or
dust or the airplane was parked during a sand or dust storm. Premature
engine deterioration can result from sand or dust ingestion, causing
increased fuel burn and reduced EGT margins.
CAUTION: After a sandstorm, if all taxiways and runways are not
carefully inspected and swept for debris before flight
ops are conducted, the risk of engine damage and wear
is increased.
Exterior Inspection
Although removal of sand and dust contaminants is primarily a
maintenance function, during the exterior inspection the captain or first
officer should carefully inspect areas where accumulation of sand or dust
could change or affect normal system operations.
Do the normal Exterior Inspection with the following additional steps:
Windshield .....................................................................................Check
Verify that the windshield has been cleaned.
Note:
Do not use windshield wipers for sand or dust removal.
Wash deposits off with water and wipe residue off with a soft
cloth.
Surfaces ..........................................................................................Check
Verify that the upper surfaces of the wings and other control
surfaces are free of sand.
CAUTION: Particular care should be taken to ensure that the
fuselage and all surfaces are clean after a sand
storm that occurs with a rain storm.
Probes, sensors, ports, ram turbine doors,
vents, and drains (as applicable) ....................................................Check
Verify that the left and right ram air inlets are free of sand and dust.
Verify that the cabin pressure outflow valve and both positive
pressure relief valves are free of sand and dust.
March 1, 2021
